Effects of bulk viscosity and hadronic rescattering in heavy ion collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ryu, Sangwook; Paquet, Jean-Francois; Shen, Chun

Here, we describe ultrarelativistic heavy ion collisions at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider with a hybrid model using the IP-Glasma model for the earliest stage and viscous hydrodynamics and microscopic transport for the later stages of the collision. We demonstrate that within this framework the bulk viscosity of the plasma plays an important role in describing the experimentally observed radial flow and azimuthal anisotropy simultaneously. Finally, we further investigate the dependence of observables on the temperature below which we employ the microscopic transport description.

Effects of bulk viscosity and hadronic rescattering in heavy ion collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

DOE PAGES

Ryu, Sangwook; Paquet, Jean-Francois; Shen, Chun; ...

2018-03-15

Here, we describe ultrarelativistic heavy ion collisions at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider with a hybrid model using the IP-Glasma model for the earliest stage and viscous hydrodynamics and microscopic transport for the later stages of the collision. We demonstrate that within this framework the bulk viscosity of the plasma plays an important role in describing the experimentally observed radial flow and azimuthal anisotropy simultaneously. Finally, we further investigate the dependence of observables on the temperature below which we employ the microscopic transport description.

Accelerating hydrodynamic description of pseudorapidity density and the initial energy density in p +p , Cu + Cu, Au + Au, and Pb + Pb collisions at energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Ze-Fang, Jiang; Chun-Bin, Yang; Csanád, Máté; Csörgő, Tamás

2018-06-01

A known class of analytic, exact, accelerating solutions of prefect relativistic hydrodynamics with longitudinal acceleration is utilized to describe results on the pseudorapidity distributions for different collision systems. These results include d N /d η measured in p +p , Cu+Cu, Au+Au, and Pb+Pb collisions at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider, in a broad centrality range. Going beyond the traditional Bjorken model, from the accelerating hydrodynamic description we determine the initial energy density and other thermodynamic quantities in those collisions.

Hadron-collider limits on new electroweak interactions from the heterotic string

DOE Office of Scientific and Technical Information (OSTI.GOV)

del Aguila, F.; Moreno, J.M.; Quiros, M.

1990-01-01

We evaluate the {ital Z}{prime}{r arrow}{ital l}{sup +}l{sup {minus}} cross section at present and future hadron colliders, for the minimal (E{sub 6}) extended electroweak models inspired by superstrings (including renormalization effects on new gauge couplings and new mixing angles). Popular models are discussed for comparison. Analytical expressions for the bounds on the mass of a new gauge boson, {ital M}{sub {ital Z}{prime}}, as a function of the bound on the ratio {ital R}{equivalent to}{sigma}({ital Z}{prime}){ital B}(Z{prime}{r arrow}l{sup +}{ital l}{sup {minus}})/{sigma}({ital Z}){ital B} ({ital Z}{r arrow}{ital l}{sup +}{ital l}{sup {minus}}), are given for the CERN S{ital p {bar p}}S, Fermilab Teva-more » tron, Serpukhov UNK, CERN Large Hadron Collider, and Superconducting Super Collider for the different models. In particular, the {ital M}{sub {ital Z}{prime}} bounds from the present {ital R} limit at CERN, as well as from the eventually available {ital R} limits at Fermilab and at the future hadron colliders (after three months of running at the expected luminosity), are given explicitly.« less

Determining the structure of Higgs couplings at the CERN LargeHadron Collider.

PubMed

Plehn, Tilman; Rainwater, David; Zeppenfeld, Dieter

2002-02-04

Higgs boson production via weak boson fusion at the CERN Large Hadron Collider has the capability to determine the dominant CP nature of a Higgs boson, via the tensor structure of its coupling to weak bosons. This information is contained in the azimuthal angle distribution of the two outgoing forward tagging jets. The technique is independent of both the Higgs boson mass and the observed decay channel.

Proceedings of the 2005 International Linear Collider Workshop (LCWS05)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hewett, JoAnne,; /SLAC

2006-12-18

Exploration of physics at the TeV scale holds the promise of addressing some of our most basic questions about the nature of matter, space, time, and energy. Discoveries of the Electroweak Symmetry Breaking mechanism, Supersymmetry, Extra Dimensions of space, Dark Matter particles, and new forces of nature are all possible. We have been waiting and planning for this exploration for over 20 years. In 2007 the Large Hadron Collider at CERN will begin its operation and will break into this new energy frontier. A new era of understanding will emerge as the LHC data maps out the Terascale. With themore » LHC discoveries, new compelling questions will arise. Responding to these questions will call for a new tool with greater sensitivity--the International Linear Collider. Historically, the most striking progress in the exploration of new energy frontiers has been made from combining results from hadron and electron-positron colliders. The precision measurements possible at the ILC will reveal the underlying theory which gave rise to the particles discovered at the LHC and will open the window to even higher energies. The world High Energy Physics community has reached an accord that an e+e- linear collider operating at 0.5-1.0 TeV would provide both unique and essential scientific opportunities; the community has endorsed with highest priority the construction of such a machine. A major milestone toward this goal was reached in August 2004 when the International Committee on Future Accelerators approved a recommendation for the technology of the future International Linear Collider. A global research and design effort is now underway to construct a global design report for the ILC. This endeavor is directed by Barry Barrish of the California Institute of Technology. The offer, made by Jonathan Dorfan on the behalf of ICFA, and acceptance of this directorship took place during the opening plenary session of this workshop. The 2005 International Linear Collider Workshop was held at Stanford University from 18 March through 22 March, 2005. This workshop was hosted by the Stanford Linear Accelerator Center and sponsored by the World Wide Study for future e+e- linear colliders. It was the eighth in a series of International Workshops (the first was held in Saariselka, Finland in 1991) devoted to the physics and detectors associated with high energy e+e- linear colliders. 397 physicists from 24 countries participated in the workshop. These proceedings represent the presentations and discussions which took place during the workshop. The contributions are comprised of physics studies, detector specifications, and accelerator design for the ILC. These proceedings are organized in two Volumes and include contributions from both the plenary and parallel sessions.« less

Measurement of the inclusive jet cross section at the CERN pp collider

NASA Astrophysics Data System (ADS)

Arnison, G.; Albrow, M. G.; Allkofer, O. C.; Astbury, A.; Aubert, B.; Bacci, C.; Batley, J. R.; Bauer, G.; Bettini, A.; Bézaguet, A.; Bock, R. K.; Bos, K.; Buckley, E.; Bunn, J.; Busetto, G.; Catz, P.; Cennini, P.; Centro, S.; Ceradini, F.; Ciapetti, G.; Cittolin, S.; Clarke, D.; Cline, D.; Cochet, C.; Colas, J.; Colas, P.; Corden, M.; Cox, G.; Dallman, D.; Dau, D.; Debeer, M.; Debrion, J. P.; Degiorgi, M.; della Negra, M.; Demoulin, M.; Denby, B.; Denegri, D.; Diciaccio, A.; Dobrzynski, L.; Dorenbosch, J.; Dowell, J. D.; Duchovni, E.; Edgecock, R.; Eggert, K.; Eisenhandler, E.; Ellis, N.; Erhard, P.; Faissner, H.; Fince Keeler, M.; Flynn, P.; Fontaine, G.; Frey, R.; Frühwirth, R.; Garvey, J.; Gee, D.; Geer, S.; Ghesquière, C.; Ghez, P.; Ghio, F.; Giacomelli, P.; Gibson, W. R.; Giraud-Héraud, Y.; Givernaud, A.; Gonidec, A.; Goodman, M.; Grassmann, H.; Grayer, G.; Guryn, W.; Hansl-Kozanecka, T.; Haynes, W.; Haywood, S. J.; Hoffmann, H.; Holthuizen, D. J.; Homer, R. J.; Homer, R. J.; Honma, A.; Jank, W.; Jimack, M.; Jorat, G.; Kalmus, P. I. P.; Karimäri, V.; Keeler, R.; Kenyon, I.; Kernan, A.; Kienzle, W.; Kinnunen, R.; Kozanecki, W.; Kroll, J.; Kryn, D.; Kyberd, P.; Lacava, F.; Laugier, J. P.; Lees, J. P.; Leuchs, R.; Levegrun, S.; Lévêque, A.; Levi, M.; Linglin, D.; Locci, E.; Long, K.; Markiewicz, T.; Markytan, M.; Martin, T.; Maurin, F.; McMahon, T.; Mendiburu, J.-P.; Meneguzzo, A.; Meyer, O.; Meyer, T.; Minard, M.-N.; Mohammadi, M.; Morgan, K.; Moricca, M.; Moser, H.; Mours, B.; Muller, Th.; Nandi, A.; Naumann, L.; Norton, A.; Paoluzi, L.; Pascoli, D.; Pauss, F.; Perault, C.; Piano Mortari, G.; Pietarinen, E.; Pigot, C.; Pimiä, M.; Pitman, D.; Placci, A.; Porte, J.-P.; Radermacher, E.; Ransdell, J.; Redelberger, T.; Reithler, H.; Revol, J. P.; Richman, J.; Rijssenbeek, M.; Rohlf, J.; Rossi, P.; Roberts, C.; Ruhm, W.; Rubbia, C.; Sajot, G.; Salvini, G.; Sass, J.; Sadoulet, B.; Samyn, D.; Savoy-Navarro, A.; Schinzel, D.; Schwartz, A.; Scott, W.; Scott, W.; Shah, T. P.; Sheer, I.; Siotis, I.; Smith, D.; Sobie, R.; Sphicas, P.; Strauss, J.; Streets, J.; Stubenrauch, C.; Summers, D.; Sumorok, K.; Szonczo, F.; Tao, C.; Ten Have, I.; Thompson, G.; Tscheslog, E.; Tuominiemi, J.; van Eijk, B.; Verecchia, P.; Vialle, J. P.; Virdee, T. S.; von der Schmitt, H.; von Schlippe, W.; Vrana, J.; Vuillemin, V.; Wahl, H. D.; Watkins, P.; Wilke, R.; Wilson, J.; Wingerter, I.; Wimpenny, S. J.; Wulz, C.-E.; Wyatt, T.; Yvert, M.; Zacharov, I.; Zaganidis, N.; Zanello, L.; Zotto, P.

1986-05-01

The inclusive jet cross section has been measured in the UA1 experiment at the CERN pp Collider at centre-of-mass energies √s = 546 GeV and √s = 630 eV. The cross sections are found to be consistent with QCD predictions, The observed change in the cross section with the centre-of-mass energy √s is accounted for in terms of xT scaling.

The LHC timeline: a personal recollection (1980-2012)

NASA Astrophysics Data System (ADS)

Maiani, Luciano; Bonolis, Luisa

2017-12-01

The objective of this interview is to study the history of the Large Hadron Collider in the LEP tunnel at CERN, from first ideas to the discovery of the Brout-Englert-Higgs boson, seen from the point of view of a member of CERN scientific committees, of the CERN Council and a former Director General of CERN in the years of machine construction.

Learning with the ATLAS Experiment at CERN

ERIC Educational Resources Information Center

Barnett, R. M.; Johansson, K. E.; Kourkoumelis, C.; Long, L.; Pequenao, J.; Reimers, C.; Watkins, P.

2012-01-01

With the start of the LHC, the new particle collider at CERN, the ATLAS experiment is also providing high-energy particle collisions for educational purposes. Several education projects--education scenarios--have been developed and tested on students and teachers in several European countries within the Learning with ATLAS@CERN project. These…

Diffractive Higgs boson production at the Fermilab Tevatron and the CERN Large Hadron Collider.

PubMed

Enberg, R; Ingelman, G; Kissavos, A; Tîmneanu, N

2002-08-19

Improved possibilities to find the Higgs boson in diffractive events, having less hadronic activity, depend on whether the cross section is large enough. Based on the soft color interaction models that successfully describe diffractive hard scattering at DESY HERA and the Fermilab Tevatron, we find that only a few diffractive Higgs events may be produced at the Tevatron, but we predict a substantial rate at the CERN Large Hadron Collider.

Anisotropic flow of thermal photons at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Chatterjee, Rupa; Dasgupta, Pingal; Srivastava, Dinesh K.

2017-07-01

We calculate elliptic and triangular flow parameters of thermal photons using an event-by-event hydrodynamic model with fluctuating initial conditions at 200 A GeV Au+Au collisions at the BNL Relativistic Heavy Ion Collider (RHIC) and at 2.76 A TeV Pb+Pb collisions at the Cern Large Hadron Collider (LHC) for three different centrality bins. The photon elliptic flow shows strong centrality dependence where v2(pT) increases towards peripheral collisions both at RHIC and at the LHC energies. However, the triangular flow parameter does not show significant dependence on the collision centrality. The elliptic as well as the triangular flow parameters found to underestimate the PHENIX data at RHIC by a large margin for all three centrality bins. We calculate pT spectrum and anisotropic flow of thermal photons from 200 A GeV Cu+Cu collisions at RHIC for a 0-20% centrality bin and compare with the results with those from Au+Au collisions. The production of thermal photons is found to decrease significantly for Cu+Cu collisions compared to Au+Au collisions. However, the effect of initial state fluctuation is found to be more pronounced for anisotropic flow, resulting in larger v2 and v3 for Cu+Cu collisions. We study the correlation between the anisotropic flow parameters and the corresponding initial spatial anisotropies from their event-by-event distributions at RHIC and at the LHC energies. The linear correlation between v2 and ɛ2 is found be stronger compared to the correlation between v3 and ɛ3. In addition, the correlation coefficient is found to be larger at LHC than at RHIC.

Hadron Collider Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Incandela, J.R.

2000-03-07

Experiments are being prepared at the Fermilab Tevatron and the CERN Large Hadron Collider that promise to deliver extraordinary insights into the nature of spontaneous symmetry breaking, and the role of supersymmetry in the universe. This article reviews the goals, challenges, and designs of these experiments. The first hadron collider, the ISR at CERN, has to overcome two initial obstacles. The first was low luminosity, which steadily improved over time. The second was the broad angular spread of interesting events. In this regard Maurice Jacob noted (1): The answer is ... sophisticated detectors covering at least the whole central regionmore » (45{degree} {le} {theta} {le} 135{degree}) and full azimuth. This statement, while obvious today, reflects the major revelation of the ISR period that hadrons have partonic substructure. The result was an unexpectedly strong hadronic yield at large transverse momentum (p{sub T}). Partly because of this, the ISR missed the discovery of the J/{psi} and later missed the {Upsilon}. The ISR era was therefore somewhat less auspicious than it might have been. It did however make important contributions in areas such as jet production and charm excitation and it paved the way for the SPS collider, also at CERN.« less

How hadron collider experiments contributed to the development of QCD: from hard-scattering to the perfect liquid

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tannenbaum, M. J.

A revolution in elementary particle physics occurred during the period from the ICHEP1968 to the ICHEP1982 with the advent of the parton model from discoveries in Deeply Inelastic electron-proton Scattering at SLAC, neutrino experiments, hard-scattering observed in p+p collisions at the CERN ISR, the development of QCD, the discovery of the J/Ψ at BNL and SLAC and the clear observation of high transverse momentum jets at the CERN SPSmore » $$\\bar{p}$$ + p collider. These and other discoveries in this period led to the acceptance of QCD as the theory of the strong interactions. The desire to understand nuclear physics at high density such as in neutron stars led to the application of QCD to this problem and to the prediction of a Quark-Gluon Plasma (QGP) in nuclei at high energy density and temperatures. This eventually led to the construction of the Relativistic Heavy Ion Collider (RHIC) at BNL to observe superdense nuclear matter in the laboratory. This article discusses how experimental methods and results which confirmed QCD at the first hadron collider, the CERN ISR, played an important role in experiments at the first heavy ion collider, RHIC, leading to the discovery of the QGP as a perfect liquid as well as discoveries at RHIC and the LHC which continue to the present day.« less

How hadron collider experiments contributed to the development of QCD: from hard-scattering to the perfect liquid

DOE PAGES

Tannenbaum, M. J.

2018-01-30

A revolution in elementary particle physics occurred during the period from the ICHEP1968 to the ICHEP1982 with the advent of the parton model from discoveries in Deeply Inelastic electron-proton Scattering at SLAC, neutrino experiments, hard-scattering observed in p+p collisions at the CERN ISR, the development of QCD, the discovery of the J/Ψ at BNL and SLAC and the clear observation of high transverse momentum jets at the CERN SPSmore » $$\\bar{p}$$ + p collider. These and other discoveries in this period led to the acceptance of QCD as the theory of the strong interactions. The desire to understand nuclear physics at high density such as in neutron stars led to the application of QCD to this problem and to the prediction of a Quark-Gluon Plasma (QGP) in nuclei at high energy density and temperatures. This eventually led to the construction of the Relativistic Heavy Ion Collider (RHIC) at BNL to observe superdense nuclear matter in the laboratory. This article discusses how experimental methods and results which confirmed QCD at the first hadron collider, the CERN ISR, played an important role in experiments at the first heavy ion collider, RHIC, leading to the discovery of the QGP as a perfect liquid as well as discoveries at RHIC and the LHC which continue to the present day.« less

How hadron collider experiments contributed to the development of QCD: from hard-scattering to the perfect liquid

NASA Astrophysics Data System (ADS)

Tannenbaum, M. J.

2018-05-01

A revolution in elementary particle physics occurred during the period from the ICHEP1968 to the ICHEP1982 with the advent of the parton model from discoveries in Deeply Inelastic electron-proton Scattering at SLAC, neutrino experiments, hard-scattering observed in p+p collisions at the CERN ISR, the development of QCD, the discovery of the J/ Ψ at BNL and SLAC and the clear observation of high transverse momentum jets at the CERN SPS p¯ + p collider. These and other discoveries in this period led to the acceptance of QCD as the theory of the strong interactions. The desire to understand nuclear physics at high density such as in neutron stars led to the application of QCD to this problem and to the prediction of a Quark-Gluon Plasma (QGP) in nuclei at high energy density and temperatures. This eventually led to the construction of the Relativistic Heavy Ion Collider (RHIC) at BNL to observe superdense nuclear matter in the laboratory. This article discusses how experimental methods and results which confirmed QCD at the first hadron collider, the CERN ISR, played an important role in experiments at the first heavy ion collider, RHIC, leading to the discovery of the QGP as a perfect liquid as well as discoveries at RHIC and the LHC which continue to the present day.

Beyond the Large Hadron Collider: A First Look at Cryogenics for CERN Future Circular Colliders

NASA Astrophysics Data System (ADS)

Lebrun, Philippe; Tavian, Laurent

Following the first experimental discoveries at the Large Hadron Collider (LHC) and the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. The study, conducted with the collaborative participation of interested institutes world-wide, considers several options for very high energy hadron-hadron, electron-positron and hadron-electron colliders to be installed in a quasi-circular underground tunnel in the Geneva basin, with a circumference of 80 km to 100 km. All these machines would make intensive use of advanced superconducting devices, i.e. high-field bending and focusing magnets and/or accelerating RF cavities, thus requiring large helium cryogenic systems operating at 4.5 K or below. Based on preliminary sets of parameters and layouts for the particle colliders under study, we discuss the main challenges of their cryogenic systems and present first estimates of the cryogenic refrigeration capacities required, with emphasis on the qualitative and quantitative steps to be accomplished with respect to the present state-of-the-art.

Preliminary design of CERN Future Circular Collider tunnel: first evaluation of the radiation environment in critical areas for electronics

NASA Astrophysics Data System (ADS)

Infantino, Angelo; Alía, Rubén García; Besana, Maria Ilaria; Brugger, Markus; Cerutti, Francesco

2017-09-01

As part of its post-LHC high energy physics program, CERN is conducting a study for a new proton-proton collider, called Future Circular Collider (FCC-hh), running at center-of-mass energies of up to 100 TeV in a new 100 km tunnel. The study includes a 90-350 GeV lepton collider (FCC-ee) as well as a lepton-hadron option (FCC-he). In this work, FLUKA Monte Carlo simulation was extensively used to perform a first evaluation of the radiation environment in critical areas for electronics in the FCC-hh tunnel. The model of the tunnel was created based on the original civil engineering studies already performed and further integrated in the existing FLUKA models of the beam line. The radiation levels in critical areas, such as the racks for electronics and cables, power converters, service areas, local tunnel extensions was evaluated.

Pursuing the Secrets of Matter, Space and Time at the Energy Frontier

NASA Astrophysics Data System (ADS)

Grannis, Paul

2003-04-01

Particle physicists have made good progress in characterizing the fundamental forces of Nature and the elementary constituents of matter, and these phenomena shaped the universe in its earliest moments. However, what we know now is likely quite incomplete, and new ingredients are expected to surface in accelerator experiments over the coming twenty years. The new results are expected to give us insights into the nature of physics at much higher energies, and thus at earlier epochs in the universe, than are probed directly and may reveal new complexity in the nature of space and time. We will discuss the nature of the new results to be expected at the expanding energy frontier from experimental programs at the Fermilab Tevatron, the CERN Large Hadron Collider, and a TeV scale electron-positron linear collider.

Linear Collider Physics Resource Book Snowmass 2001

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ronan

The American particle physics community can look forward to a well-conceived and vital program of experimentation for the next ten years, using both colliders and fixed target beams to study a wide variety of pressing questions. Beyond 2010, these programs will be reaching the end of their expected lives. The CERN LHC will provide an experimental program of the first importance. But beyond the LHC, the American community needs a coherent plan. The Snowmass 2001 Workshop and the deliberations of the HEPAP subpanel offer a rare opportunity to engage the full community in planning our future for the next decademore » or more. A major accelerator project requires a decade from the beginning of an engineering design to the receipt of the first data. So it is now time to decide whether to begin a new accelerator project that will operate in the years soon after 2010. We believe that the world high-energy physics community needs such a project. With the great promise of discovery in physics at the next energy scale, and with the opportunity for the uncovering of profound insights, we cannot allow our field to contract to a single experimental program at a single laboratory in the world. We believe that an e{sup +}e{sup -} linear collider is an excellent choice for the next major project in high-energy physics. Applying experimental techniques very different from those used at hadron colliders, an e{sup +}e{sup -} linear collider will allow us to build on the discoveries made at the Tevatron and the LHC, and to add a level of precision and clarity that will be necessary to understand the physics of the next energy scale. It is not necessary to anticipate specific results from the hadron collider programs to argue for constructing an e{sup +}e{sup -} linear collider; in any scenario that is now discussed, physics will benefit from the new information that e{sup +}e{sup -} experiments can provide. This last point merits further emphasis. If a new accelerator could be designed and built in a few years, it would make sense to wait for the results of each accelerator before planning the next one. Thus, we would wait for the results from the Tevatron before planning the LHC experiments, and wait for the LHC before planning any later stage. In reality accelerators require a long time to construct, and they require such specialized resources and human talent that delay can cripple what would be promising opportunities. In any event, we believe that the case for the linear collider is so compelling and robust that we can justify this facility on the basis of our current knowledge, even before the Tevatron and LHC experiments are done. The physics prospects for the linear collider have been studied intensively for more than a decade, and arguments for the importance of its experimental program have been developed from many different points of view. This book provides an introduction and a guide to this literature. We hope that it will allow physicists new to the consideration of linear collider physics to start from their own personal perspectives and develop their own assessments of the opportunities afforded by a linear collider.« less

Charm and the rise of the pp-bar total cross section

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jones, S.T.; Dash, J.W.

We give a detailed description of the pp-bar forward amplitude through CERN SPS collider energies, using the flavored Pomeron model as an effective parametrization of nonperturbative QCD. We show that the rise in the total cross section between CERN ISR and SPS collider energies is consistent with the onset of charmed-particle production up to the level of a few millibarns, along with other processes, and in agreement with available data. In contrast with our estimates of charm production, perturbative QCD charm-production calculations are well below the data. We give estimates of the p-bar and K/sup +- / multiplicities at SPSmore » collider energies. We also present a simplified version of the flavoring model in order to facilitate comparisons between it and other parametrizations.« less

Neutrino Factory Plans at CERN

NASA Astrophysics Data System (ADS)

Riche, J. A.

2002-10-01

The considerable interest raised by the discovery of neutrino oscillations and recent progress in studies of muon colliders has triggered interest in considering a neutrino factory at CERN. This paper explains the reference scenario, indicates the other possible choices and mentions the R&D that are foreseen.

Relativistic Hydrodynamics for Heavy-Ion Collisions

ERIC Educational Resources Information Center

Ollitrault, Jean-Yves

2008-01-01

Relativistic hydrodynamics is essential to our current understanding of nucleus-nucleus collisions at ultrarelativistic energies (current experiments at the Relativistic Heavy Ion Collider, forthcoming experiments at the CERN Large Hadron Collider). This is an introduction to relativistic hydrodynamics for graduate students. It includes a detailed…

W production at large transverse momentum at the CERN Large Hadron Collider.

PubMed

Gonsalves, Richard J; Kidonakis, Nikolaos; Sabio Vera, Agustín

2005-11-25

We study the production of W bosons at large transverse momentum in pp collisions at the CERN Large Hadron Collider. We calculate the complete next-to-leading order (NLO) corrections to the differential cross section. We find that the NLO corrections provide a large increase to the cross section but, surprisingly, do not reduce the scale dependence relative to leading order (LO). We also calculate next-to-next-to-leading-order (NNLO) soft-gluon corrections and find that, although they are small, they significantly reduce the scale dependence thus providing a more stable result.

Lower limit on dark matter production at the CERN Large Hadron Collider.

PubMed

Feng, Jonathan L; Su, Shufang; Takayama, Fumihiro

2006-04-21

We evaluate the prospects for finding evidence of dark matter production at the CERN Large Hadron Collider. We consider weakly interacting massive particles (WIMPs) and superWIMPs and characterize their properties through model-independent parametrizations. The observed relic density then implies lower bounds on dark matter production rates as functions of a few parameters. For WIMPs, the resulting signal is indistinguishable from background. For superWIMPs, however, this analysis implies significant production of metastable charged particles. For natural parameters, these rates may far exceed Drell-Yan cross sections and yield spectacular signals.

Development work for a superconducting linear collider

NASA Technical Reports Server (NTRS)

Matheisen, Axel

1995-01-01

For future linear e(+)e(-) colliders in the TeV range several alternatives are under discussion. The TESLA approach is based on the advantages of superconductivity. High Q values of the accelerator structures give high efficiency for converting RF power into beam power. A low resonance frequency for the RF structures can be chosen to obtain a large number of electrons (positrons) per bunch. For a given luminosity the beam dimensions can be chosen conservatively which leads to relaxed beam emittance and tolerances at the final focus. Each individual superconducting accelerator component (resonator cavity) of this linear collider has to deliver an energy gain of 25 MeV/m to the beam. Today s.c. resonators are in use at CEBAF/USA, at DESY/Germany, Darmstadt/Germany KEK/Japan and CERN/Geneva. They show acceleration gradients between 5 MV/m and 10 MV/m. Encouraging experiments at CEA Saclay and Cornell University showed acceleration gradients of 20 MV/m and 25 MV/m in single and multicell structures. In an activity centered at DESY in Hamburg/Germany the TESLA collaboration is constructing a 500 MeV superconducting accelerator test facility (TTF) to demonstrate that a linear collider based on this technique can be built in a cost effective manner and that the necessary acceleration gradients of more than 15 MeV/m can be reached reproducibly. The test facility built at DESY covers an area of 3.000 m2 and is divided into 3 major activity areas: (1) The testlinac, where the performance ofthe modular components with an electron beam passing the 40 m long acceleration section can be demonstrated. (2) The test area, where all individual resonators are tested before installation into a module. (3) The preparation and assembly area, where assembly of cavities and modules take place. We report here on the design work to reach a reduction of costs compared to actual existing superconducting accelerator structures and on the facility set up to reach high acceleration gradients in a reproducible way.

Lead ions and Coulomb’s Law at the LHC (CERN)

NASA Astrophysics Data System (ADS)

Cid-Vidal, Xabier; Cid, Ramon

2018-03-01

Although for most of the time the Large Hadron Collider (LHC) at CERN collides protons, for around one month every year lead ions are collided, to expand the diversity of the LHC research programme. Furthermore, in an effort not originally foreseen, proton-lead collisions are also taking place, with results of high interest to the physics community. All the large experiments of the LHC have now joined the heavy-ion programme, including the LHCb experiment, which was not at first expected to be part of it. The aim of this article is to introduce a few simple physical calculations relating to some electrical phenomena that occur when lead-ion bunches are running in the LHC, using Coulomb’s Law, to be taken to the secondary school classroom to help students understand some important physical concepts.

Probing small parton densities in ultraperipheral A A and pA collisions at the CERN large Hadron Collider.

PubMed

Strikman, Mark; Vogt, Ramona; White, Sebastian

2006-03-03

We calculate photoproduction rates for several hard processes in ultraperipheral proton-lead and lead-lead collisions at the CERN Large Hadron Collider (LHC) with square root of sNN = 8.8 and 5.5 TeV, respectively, which could be triggered in the large LHC detectors. We use ATLAS as an example. The lead ion is treated as a source of (coherently produced) photons with energies and intensities greater than those of equivalent ep collisions at the DESY collider HERA. We find very large rates for both inclusive and diffractive production that will extend the HERA x range by nearly an order of magnitude for similar virtualities. We demonstrate that it is possible to reach the kinematic regime where nonlinear effects are larger than at HERA.

Matter, Energy, Space and Time: The International Linear Collider Physics Prospects and International Aspects

NASA Astrophysics Data System (ADS)

Wagner, Albrecht

2006-04-01

Over the past century, physicists have sought to explain the character of the matter and energy in our universe, to show how the basic forces of nature and the building blocks of matter come about, and to explore the fabric of space and time. In the past three decades, experiments at laboratories around the world have given us a precise confirmation of the underlying theory called the standard model. These particle physics advances have a direct impact for our understanding of the structure of the universe, both at its inception in the Big Bang, and in its evolution to the present and future. The final synthesis is not yet fully clear, but we know with confidence that major discoveries expanding the standard model framework will occur at the next generation of accelerators. The Large Hadron Collider (LHC) being built at CERN will take us into the discovery realm. The proposed International Linear Collider (ILC) will extend the discoveries and provide a wealth of precision measurements that are essential for giving deeper understanding of their meaning, and pointing the way to further evolution of particle physics in the future. A world-wide consensus has formed for a baseline ILC project at energies of 500 GeV and beyond. The choice of the superconducting technology as basis for the ILC has paved the way for a global design effort which has now taken full speed.

Build your own

NASA Astrophysics Data System (ADS)

Moniz, Ernest; McAndrew, Elizabeth; Chan, Albert; Eggleton, David

2015-01-01

In reply to the physicsworld.com blog post "Build your own LEGO particle collider" (2 December 2014, http://ow.ly/Fe3Vy, see also p3) which described a campaign to get the popular plastic-bricks firm to make a building set based on a particle accelerator, such as the Large Hadron Collider at CERN.

Radiative return capabilities of a high-energy, high-luminosity e + e - collider

DOE PAGES

Karliner, Marek; Low, Matthew; Rosner, Jonathan L.; ...

2015-08-14

An electron-positron collider operating at a center-of-mass energy E CM can collect events at all lower energies through initial-state radiation (ISR or radiative return). We explore the capabilities for radiative return studies by a proposed high-luminosity collider at E CM = 250 or 90 GeV, to fill in gaps left by lower-energy colliders such as PEP, PETRA, TRISTAN, and LEP. These capabilities are compared with those of the lower-energy e +e - colliders as well as hadron colliders such as the Tevatron and the CERN Large Hadron Collider (LHC). Some examples of accessible questions in dark photon searches and heavymore » flavor spectroscopy are given.« less

Black Holes and the Large Hadron Collider

ERIC Educational Resources Information Center

Roy, Arunava

2011-01-01

The European Center for Nuclear Research or CERN's Large Hadron Collider (LHC) has caught our attention partly due to the film "Angels and Demons." In the movie, an antimatter bomb attack on the Vatican is foiled by the protagonist. Perhaps just as controversial is the formation of mini black holes (BHs). Recently, the American Physical Society…

Higgs-boson production in nucleus-nucleus collisions

NASA Technical Reports Server (NTRS)

Norbury, J. W.; Townsend, L. W. (Principal Investigator)

1990-01-01

Cross-section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two-photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two-photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

Higgs-Boson Production in Nucleus-Nucleus Collisions

NASA Technical Reports Server (NTRS)

Norbury, John W.

1992-01-01

Cross section calculations are presented for the production of intermediate-mass Higgs bosons produced in ultrarelativistic nucleus-nucleus collisions via two photon fusion. The calculations are performed in position space using Baur's method for folding together the Weizsacker-Williams virtual-photon spectra of the two colliding nuclei. It is found that two photon fusion in nucleus-nucleus collisions is a plausible way of finding intermediate-mass Higgs bosons at the Superconducting Super Collider or the CERN Large Hadron Collider.

Development of Resistive Micromegas for Sampling Calorimetry

NASA Astrophysics Data System (ADS)

Geralis, T.; Fanourakis, G.; Kalamaris, A.; Nikas, D.; Psallidas, A.; Chefdeville, M.; Karyotakis, I.; Koletsou, I.; Titov, M.

2018-02-01

Resistive micromegas is proposed as an active element for sampling calorimetry. Future linear collider experiments or the HL-LHC experiments can profit from those developments for Particle Flow Calorimetry. Micromegas possesses remarkable properties concerning gain stability, reduced ion feedback, response linearity, adaptable sensitive element granularity, fast response and high rate capability. Recent developments on Micromegas with a protective resistive layer present excellent results, resolving the problem of discharges caused by local high charge deposition, thanks to its RC-slowed charge evacuation. Higher resistivity though, may cause loss of the response linearity at high rates. We have scanned a wide range of resistivities and performed laboratory tests with X-rays that demonstrate excellent response linearity up to rates of (a few) times 10MHz/cm2, with simultaneous mitigation of discharges. Beam test studies at SPS/CERN with hadrons have also shown a remarkable stability of the resistive Micromegas and low currents for rates up to 15MHz/cm2. We present results from the aforementioned studies confronted with MC simulation

One-side forward-backward asymmetry in top quark pair production at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang Youkai; Xiao Bo; Zhu Shouhua

2010-11-01

Both D0 and CDF at Tevatron reported the measurements of forward-backward asymmetry in top pair production, which showed possible deviation from the standard model QCD prediction. In this paper, we explore how to examine the same higher-order QCD effects at the more powerful Large Hadron Collider.

The Higgs Boson: Is the End in Sight?

ERIC Educational Resources Information Center

Lincoln, Don

2012-01-01

This summer, perhaps while you were lounging around the pool in the blistering heat, the blogosphere was buzzing about data taken at the Large Hadron Collider at CERN. The buzz reached a crescendo in the first week of July when both Fermilab and CERN announced the results of their searches for the Higgs boson. Hard data confronted a theory nearly…

First a tragedy, then farce

NASA Astrophysics Data System (ADS)

Foster, Brian

2008-09-01

It is impossible to think about the problems in the UK over the last 10 months arising from the £80m shortfall in the budget of the Science and Technology Facilities Council (STFC) without recalling Marx's famous aphorism: "History repeats itself, first as tragedy, then as farce." Certainly the repetition of a funding crisis in UK particle physics and astronomy is hardly unexpected; they seem to occur every decade or so with unwelcome regularity. The consequent loss of morale, jobs and opportunities in the UK for the brightest young people to pursue their dreams in what is widely acknowledged to be world-class science is a tragedy. What perhaps marks the uniqueness of the funding crisis this time round is the level of farce. The sums that did not add up; the consultations without interlocutors; and the truculent and damaging statements about withdrawal from the Gemini telescopes based in Hawaii and Chile, and the International Linear Collider (ILC) - the next big particle-physics project after the Large Hadron Collider (LHC) at CERN.

Accelerators for America's Future

NASA Astrophysics Data System (ADS)

Bai, Mei

2016-03-01

Particle accelerator, a powerful tool to energize beams of charged particles to a desired speed and energy, has been the working horse for investigating the fundamental structure of matter and fundermental laws of nature. Most known examples are the 2-mile long Stanford Linear Accelerator at SLAC, the high energy proton and anti-proton collider Tevatron at FermiLab, and Large Hadron Collider that is currently under operation at CERN. During the less than a century development of accelerator science and technology that led to a dazzling list of discoveries, particle accelerators have also found various applications beyond particle and nuclear physics research, and become an indispensible part of the economy. Today, one can find a particle accelerator at almost every corner of our lives, ranging from the x-ray machine at the airport security to radiation diagnostic and therapy in hospitals. This presentation will give a brief introduction of the applications of this powerful tool in fundermental research as well as in industry. Challenges in accelerator science and technology will also be briefly presented

First experimental evidence of hydrodynamic tunneling of ultra-relativistic protons in extended solid copper target at the CERN HiRadMat facility

NASA Astrophysics Data System (ADS)

Schmidt, R.; Blanco Sancho, J.; Burkart, F.; Grenier, D.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.

2014-08-01

A novel experiment has been performed at the CERN HiRadMat test facility to study the impact of the 440 GeV proton beam generated by the Super Proton Synchrotron on extended solid copper cylindrical targets. Substantial hydrodynamic tunneling of the protons in the target material has been observed that leads to significant lengthening of the projectile range, which confirms our previous theoretical predictions [N. A. Tahir et al., Phys. Rev. Spec. Top.-Accel. Beams 15, 051003 (2012)]. Simulation results show very good agreement with the experimental measurements. These results have very important implications on the machine protection design for powerful machines like the Large Hadron Collider (LHC), the future High Luminosity LHC, and the proposed huge 80 km circumference Future Circular Collider, which is currently being discussed at CERN. Another very interesting outcome of this work is that one may also study the field of High Energy Density Physics at this test facility.

Angular distributions for high-mass jet pairs and a limit on the energy scale of compositeness for quarks from the CERN pp¯ collider

NASA Astrophysics Data System (ADS)

Arnison, G.; Albajar, C.; Albrow, M. G.; Allkofer, O. C.; Astbury, A.; Aubert, B.; Axon, T.; Bacci, C.; Bacon, T.; Batley, J. R.; Bauer, G.; Bellinger, J.; Bettini, A.; Bézaguet, A.; Bock, R. K.; Bos, K.; Buckley, E.; Busetto, G.; Catz, P.; Cennini, P.; Centro, S.; Ceradini, F.; Ciapetti, G.; Cittolin, S.; Clarke, D.; Cline, D.; Cochet, C.; Colas, J.; Colas, P.; Corden, M.; Coughlan, J. A.; Cox, G.; Dau, D.; Debeer, M.; Debrion, J. P.; Degiorgi, M.; Della Negra, M.; Demoulin, M.; Denby, B.; Denegri, D.; Diciaccio, A.; Dobrzynski, L.; Dorenbosch, J.; Dowell, J. D.; Duchovni, E.; Edgecock, R.; Eggert, K.; Eisenhandler, E.; Ellis, N.; Erhard, P.; Faissner, H.; Keeler, M. Fincke; Flynn, P.; Fontaine, G.; Frey, R.; Frühwirth, R.; Garvey, J.; Gee, D.; Geer, S.; Ghesquière, C.; Ghez, P.; Ghio, F.; Giacomelli, P.; Gibson, W. R.; Giraud-Héraud, Y.; Givernaud, A.; Gonidec, A.; Goodman, M.; Grassmann, H.; Grayer, G.; Guryn, W.; Hansl-Kozanecka, T.; Haynes, W.; Haywood, S. J.; Hoffmann, H.; Holthuizen, D. J.; Homer, R. J.; Honma, A.; Ikeda, M.; Jank, W.; Jimack, M.; Jorat, G.; Kalmus, P. I. P.; Karimäki, V.; Keeler, R.; Kenyon, I.; Kernan, A.; Kienzle, W.; Kinnunen, R.; Kozanecki, W.; Krammer, M.; Kroll, J.; Kryn, D.; Kyberd, P.; Lacava, F.; Laugier, J. P.; Lees, J. P.; Leuchs, R.; Levegrun, S.; Lévêque, A.; Levi, M.; Linglin, D.; Locci, E.; Long, K.; Markiewicz, T.; Markytan, M.; Martin, T.; Maurin, G.; McMahon, T.; Mendiburu, J.-P.; Meneguzzo, A.; Meyer, O.; Meyer, T.; Minard, M.-N.; Mohammad, M.; Morgan, K.; Moricca, M.; Moser, H.; Mours, B.; Muller, Th.; Nandi, A.; Naumann, L.; Norton, A.; Pascoli, D.; Pauss, F.; Perault, C.; Petrolo, E.; Mortari, G. Piano; Pietarinen, E.; Pigot, C.; Pimiä, M.; Pitman, D.; Placci, A.; Porte, J.-P.; Radermacher, E.; Ransdell, J.; Redelberger, T.; Reithler, H.; Revol, J. P.; Richman, J.; Rijssenbeek, M.; Robinson, D.; Rohlf, J.; Rossi, P.; Ruhm, W.; Rubbia, C.; Sajot, G.; Salvini, G.; Sass, J.; Sadoulet, B.; Samyn, D.; Savoy-Navarro, A.; Schinzel, D.; Schwartz, A.; Scott, W.; Shah, T. P.; Sheer, I.; Siotis, I.; Smith, D.; Sobie, R.; Sphicas, P.; Strauss, J.; Streets, J.; Stubenrauch, C.; Summers, D.; Sumorok, K.; Szoncso, F.; Tao, C.; Taurok, A.; Have, I. Ten; Tether, S.; Thompson, G.; Tscheslog, E.; Tuominiemi, J.; Van Eijk, B.; Verecchia, P.; Vialle, J. P.; Villasenor, L.; Virdee, T. S.; Von der Schmitt, H.; Von Schlippe, W.; Vrana, J.; Vuillemin, V.; Wahl, H. D.; Watkins, P.; Wildish, A.; Wilke, R.; Wilson, J.; Wingerter, I.; Wimpenny, S. J.; Wulz, C. E.; Wyatt, T.; Yvert, M.; Zaccardelli, C.; Zacharov, I.; Zaganidis, N.; Zanello, L.; Zotto, P.; UA1 Collaboration

1986-09-01

Angular distributions of high-mass jet pairs (180< m2 J<350 GeV) have been measured in the UA1 experiment at the CERN pp¯ Collider ( s=630 GeV) . We show that angular distributions are independent of the subprocess centre-of-mass (CM) energy over this range, and use the data to put constraints on the definition of the Q2 scale. The distribution for the very high mass jet pairs (240< m2 J<300 GeV) has also been used to obtain a lower limit on the energy scale Λ c of compositeness of quarks. We find Λ c>415 GeV at 95% confidence level.

Photoproduction of vector mesons in proton-proton ultraperipheral collisions at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Xie, Ya-Ping; Chen, Xurong

2018-05-01

Photoproduction of vector mesons is computed with dipole model in proton-proton ultraperipheral collisions (UPCs) at the CERN Large Hadron Collider (LHC). The dipole model framework is employed in the calculations of vector mesons production in diffractive processes. Parameters of the bCGC model are refitted with the latest inclusive deep inelastic scattering experimental data. Employing the bCGC model and boosted Gaussian light-cone wave function for vector mesons, we obtain the prediction of rapidity distributions of J/ψ and ψ(2s) mesons in proton-proton ultraperipheral collisions at the LHC. The predictions give a good description of the experimental data of LHCb. Predictions of ϕ and ω mesons are also evaluated in this paper.

Black holes in many dimensions at the CERN Large Hadron Collider: testing critical string theory.

PubMed

Hewett, JoAnne L; Lillie, Ben; Rizzo, Thomas G

2005-12-31

We consider black hole production at the CERN Large Hadron Collider (LHC) in a generic scenario with many extra dimensions where the standard model fields are confined to a brane. With approximately 20 dimensions the hierarchy problem is shown to be naturally solved without the need for large compactification radii. We find that in such a scenario the properties of black holes can be used to determine the number of extra dimensions, . In particular, we demonstrate that measurements of the decay distributions of such black holes at the LHC can determine if is significantly larger than 6 or 7 with high confidence and thus can probe one of the critical properties of string theory compactifications.

Landscape of supersymmetric particle mass hierarchies and their signature space at the CERN Large Hadron Collider.

PubMed

Feldman, Daniel; Liu, Zuowei; Nath, Pran

2007-12-21

The minimal supersymmetric standard model with soft breaking has a large landscape of supersymmetric particle mass hierarchies. This number is reduced significantly in well-motivated scenarios such as minimal supergravity and alternatives. We carry out an analysis of the landscape for the first four lightest particles and identify at least 16 mass patterns, and provide benchmarks for each. We study the signature space for the patterns at the CERN Large Hadron Collider by analyzing the lepton+ (jet> or =2) + missing P{T} signals with 0, 1, 2, and 3 leptons. Correlations in missing P{T} are also analyzed. It is found that even with 10 fb{-1} of data a significant discrimination among patterns emerges.

Suppression of high-pT hadrons in Pb+Pb collisions at energies available at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Chen, Xiao-Fang; Hirano, Tetsufumi; Wang, Enke; Wang, Xin-Nian; Zhang, Hanzhong

2011-09-01

The nuclear modification factor RAA(pT) for large transverse momentum pion spectra in Pb+Pb collisions at s=2.76 TeV is predicted within the next-to-leading order perturbative QCD parton model. The effect of jet quenching is incorporated through medium-modified fragmentation functions within the higher-twist approach. The jet transport parameter that controls medium modification is proportional to the initial parton density, and the coefficient is fixed by data on the suppression of large-pT hadron spectra obtained at the BNL Relativistic Heavy Ion Collider. Data on charged hadron multiplicity dNch/dη=1584±80 in central Pb+Pb collisions from the ALICE experiment at the CERN Large Hadron Collider are used to constrain the initial parton density both for determining the jet transport parameter and the 3 + 1 dimensional (3 + 1D) ideal hydrodynamic evolution of the bulk matter that is employed for the calculation of RPbPb(pT) for neutral pions.

Role of net baryon density on rapidity width of identified particles from the lowest energies available at the CERN Super Proton Synchrotron to those at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Hussain, Nur; Bhattacharjee, Buddhadeb

2017-08-01

Widths of the rapidity distributions of various identified hadrons generated with the UrQMD-3.4 event generator at all the Super Proton Synchrotron (SPS) energies have been presented and compared with the existing experimental results. An increase in the width of the rapidity distribution of Λ could be seen with both Monte Carlo (MC) and experimental data for the studied energies. Using MC data, the study has been extended to Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies. A similar jump, as observed in the plot of rapidity width versus rest mass at Alternating Gradient Synchrotron (AGS) and all SPS energies, persists even at RHIC and LHC energies, confirming its universal nature from AGS to the highest LHC energies. Such observation indicates that pair production may not be the only mechanism of particle production at the highest LHC energies. However, with MC data, the separate mass scaling for mesons and baryons is found to exist even at the top LHC energy.

Diagnostics of the Fermilab Tevatron using an AC dipole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Miyamoto, Ryoichi

2008-08-01

The Fermilab Tevatron is currently the world's highest energy colliding beam facility. Its counter-rotating proton and antiproton beams collide at 2 TeV center-of-mass. Delivery of such intense beam fluxes to experiments has required improved knowledge of the Tevatron's beam optical lattice. An oscillating dipole magnet, referred to as an AC dipole, is one of such a tool to non-destructively assess the optical properties of the synchrotron. We discusses development of an AC dipole system for the Tevatron, a fast-oscillating (f ~ 20 kHz) dipole magnet which can be adiabatically turned on and off to establish sustained coherent oscillations of themore » beam particles without affecting the transverse emittance. By utilizing an existing magnet and a higher power audio amplifier, the cost of the Tevatron AC dipole system became relatively inexpensive. We discuss corrections which must be applied to the driven oscillation measurements to obtain the proper interpretation of beam optical parameters from AC dipole studies. After successful operations of the Tevatron AC dipole system, AC dipole systems, similar to that in the Tevatron, will be build for the CERN LHC. We present several measurements of linear optical parameters (beta function and phase advance) for the Tevatron, as well as studies of non-linear perturbations from sextupole and octupole elements.« less

[The CERN and the megascience].

PubMed

Aguilar Peris, José

2006-01-01

In this work we analyse the biggest particle accelerator in the world: the LHC (Large Hadron Collider). The ring shaped tunnel is 27 km long and it is buried over 110 meters underground, straddling the border betwen France and Switzerland at the CERN laboratory near Geneva. Its mission is to recreate the conditions that existed shortly after the Big-Bang and to look for the hypothesised Higgs particle. The LHC will accelerate protons near the speed of the light and collide them head on at an energy of to 14 TeV (1 TeV = 10(12) eV). Keeping such high energy in the proton beams requires enormous magnetic fields which are generated by superconducting electromagnets chilled to less than two degrees above absolute zero. It is expected that LHC will be inaugurated in summer 2007.

Next Linear Collider Home Page

Science.gov Websites

Welcome to the Next Linear Collider NLC Home Page If you would like to learn about linear colliders in general and about this next-generation linear collider project's mission, design ideas, and Linear Collider. line | NLC Home | NLC Technical | SLAC | mcdunn Tuesday, February 14, 2006 01:32:11 PM

HIGH ENERGY PHYSICS: CERN Link Breathes Life Into Russian Physics.

PubMed

Stone, R

2000-10-13

Without fanfare, 600 Russian scientists here at CERN, the European particle physics laboratory, are playing key roles in building the Large Hadron Collider (LHC), a machine that will explore fundamental questions such as why particles have mass, as well as search for exotic new particles whose existence would confirm supersymmetry, a popular theory that aims to unify the four forces of nature. In fact, even though Russia is not one of CERN's 20 member states, most top high-energy physicists in Russia are working on the LHC. Some say their work could prove the salvation of high-energy physics back home.

First experimental evidence of hydrodynamic tunneling of ultra–relativistic protons in extended solid copper target at the CERN HiRadMat facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmidt, R.; Grenier, D.; Wollmann, D.

2014-08-15

A novel experiment has been performed at the CERN HiRadMat test facility to study the impact of the 440 GeV proton beam generated by the Super Proton Synchrotron on extended solid copper cylindrical targets. Substantial hydrodynamic tunneling of the protons in the target material has been observed that leads to significant lengthening of the projectile range, which confirms our previous theoretical predictions [N. A. Tahir et al., Phys. Rev. Spec. Top.-Accel. Beams 15, 051003 (2012)]. Simulation results show very good agreement with the experimental measurements. These results have very important implications on the machine protection design for powerful machines like themore » Large Hadron Collider (LHC), the future High Luminosity LHC, and the proposed huge 80 km circumference Future Circular Collider, which is currently being discussed at CERN. Another very interesting outcome of this work is that one may also study the field of High Energy Density Physics at this test facility.« less

The Next Linear Collider Program-News

Science.gov Websites

The Next Linear Collider at SLAC Navbar The Next Linear Collider In The Press The Secretary of Linear Collider is a high-priority goal of this plan. http://www.sc.doe.gov/Sub/Facilities_for_future/20 -term projects in conceputal stages (the Linear Collider is the highest priority project in this

OBITUARY: Maurice Jacob (1933 2007)

NASA Astrophysics Data System (ADS)

Quercigh, Emanuele; Šándor, Ladislav

2008-04-01

Maurice Jacob passed away on 2 May 2007. With his death, we have lost one of the founding fathers of the ultra-relativistic heavy ion programme. His interest in high-energy nuclear physics started in 1981 when alpha alpha collisions could first be studied in the CERN ISR. An enthusiastic supporter of ion beam experiments at CERN, Maurice was at the origin of the 1982 Quark Matter meeting in Bielefeld [1] which brought together more than 100 participants from both sides of the Atlantic, showing a good enthusiastic constituency for such research. There were twice as many the following year at Brookhaven. Finally in the mid-eighties, a heavy ion programme was approved both at CERN and at Brookhaven involving as many nuclear as particle physicists. It was the start of a fruitful interdisciplinary collaboration which is nowadays continuing both at RHIC and at LHC. Maurice followed actively the development of this field, reporting at a number of conferences and meetings (Les Arcs, Bielefeld, Beijing, Brookhaven, Lenox, Singapore, Taormina,...). This activity culminated in 2000, when Maurice, together with Ulrich Heinz, summarized the main results of the CERN SPS heavy-ion experiments and the evidence was obtained for a new state of matter [2]. Maurice was a brilliant theoretical physicist. His many contributions have been summarized in a recent article in the CERN Courier by two leading CERN theorists, John Ellis and Andre Martin [3]. The following is an excerpt from their article: `He began his research career at Saclay and, while still a PhD student, he continued brilliantly during a stay at Brookhaven. It was there in 1959 that Maurice, together with Giancarlo Wick, developed the helicity amplitude formalism that is the basis of many modern theoretical calculations. Maurice obtained his PhD in 1961 and, after a stay at Caltech, returned to Saclay. A second American foray was to SLAC, where he and Sam Berman made the crucial observation that the point-like structures (partons) seen in deep-inelastic scattering implied the existence of high-transverse-momentum processes in proton proton collisions, as the ISR at CERN subsequently discovered. In 1967 Maurice joined CERN, where he remained, apart from influential visits to Yale, Fermilab and elsewhere, until his retirement in 1998. He became one of the most respected international experts on the phenomenology of strong interactions, including diffraction, scaling, high-transverse-momentum processes and the formation of quark gluon plasma. In particular, he pioneered the studies of inclusive hadron-production processes, including scaling and its violations. Also, working with Ron Horgan, he made detailed predictions for the production of jets at CERN's proton antiproton collider. The UA2 and UA1 experiments subsequently discovered these. He was also interested in electron positron colliders, making pioneering calculations, together with Tai Wu, of radiation in high-energy collisions. Maurice was one of the scientific pillars of CERN, working closely with experimental colleagues in predicting and interpreting results from successive CERN colliders. He was indefatigable in organizing regular meetings on ISR physics, bringing together theorists and experimentalists to debate the meaning of new results and propose new measurements. He was one of the strongest advocates of Carlo Rubbia's proposal for a proton antiproton collider at CERN, and was influential in preparing and advertising its physics. In 1978 he organized the Les Houches workshop that brought the LEP project to the attention of the wider European particle physics community. He also organized the ECFA workshop at Lausanne in 1984 that made the first exploration of the possible physics of the LHC. It is a tragedy that Maurice has not lived to enjoy data from the LHC.' References [1] Maurice Jacob and Helmut Satz (eds) 1982 Proc. Workshop on Quark Matter Formation and Heavy Ion Collisions, Bielefeld, 10 14 May 1982 (Singapore: World Scientific Publishing) [2] Heinz Ulrich W and Jacob Maurice 2000 Evidence for a new state of matter: An assessment of the results from the CERN lead beam program. Preprint nucl-th/0002042 [3] Ellis J and Martin A 2007 CERN Courier 47 issue 6

Big data analytics for the Future Circular Collider reliability and availability studies

NASA Astrophysics Data System (ADS)

Begy, Volodimir; Apollonio, Andrea; Gutleber, Johannes; Martin-Marquez, Manuel; Niemi, Arto; Penttinen, Jussi-Pekka; Rogova, Elena; Romero-Marin, Antonio; Sollander, Peter

2017-10-01

Responding to the European Strategy for Particle Physics update 2013, the Future Circular Collider study explores scenarios of circular frontier colliders for the post-LHC era. One branch of the study assesses industrial approaches to model and simulate the reliability and availability of the entire particle collider complex based on the continuous monitoring of CERN’s accelerator complex operation. The modelling is based on an in-depth study of the CERN injector chain and LHC, and is carried out as a cooperative effort with the HL-LHC project. The work so far has revealed that a major challenge is obtaining accelerator monitoring and operational data with sufficient quality, to automate the data quality annotation and calculation of reliability distribution functions for systems, subsystems and components where needed. A flexible data management and analytics environment that permits integrating the heterogeneous data sources, the domain-specific data quality management algorithms and the reliability modelling and simulation suite is a key enabler to complete this accelerator operation study. This paper describes the Big Data infrastructure and analytics ecosystem that has been put in operation at CERN, serving as the foundation on which reliability and availability analysis and simulations can be built. This contribution focuses on data infrastructure and data management aspects and presents case studies chosen for its validation.

PARTICLE PHYSICS: CERN Collider Glimpses Supersymmetry--Maybe.

PubMed

Seife, C

2000-07-14

Last week, particle physicists at the CERN laboratory in Switzerland announced that by smashing together matter and antimatter in four experiments, they detected an unexpected effect in the sprays of particles that ensued. The anomaly is subtle, and physicists caution that it might still be a statistical fluke. If confirmed, however, it could mark the long-sought discovery of a whole zoo of new particles--and the end of a long-standing model of particle physics.

Heavy-ion physics with the ALICE experiment at the CERN Large Hadron Collider.

PubMed

Schukraft, J

2012-02-28

After close to 20 years of preparation, the dedicated heavy-ion experiment A Large Ion Collider Experiment (ALICE) took first data at the CERN Large Hadron Collider (LHC) accelerator with proton collisions at the end of 2009 and with lead nuclei at the end of 2010. After a short introduction into the physics of ultra-relativistic heavy-ion collisions, this article recalls the main design choices made for the detector and summarizes the initial operation and performance of ALICE. Physics results from this first year of operation concentrate on characterizing the global properties of typical, average collisions, both in proton-proton (pp) and nucleus-nucleus reactions, in the new energy regime of the LHC. The pp results differ, to a varying degree, from most quantum chromodynamics-inspired phenomenological models and provide the input needed to fine tune their parameters. First results from Pb-Pb are broadly consistent with expectations based on lower energy data, indicating that high-density matter created at the LHC, while much hotter and larger, still behaves like a very strongly interacting, almost perfect liquid.

Higher moments of multiplicity fluctuations in a hadron-resonance gas with exact conservation laws

NASA Astrophysics Data System (ADS)

Fu, Jing-Hua

2017-09-01

Higher moments of multiplicity fluctuations of hadrons produced in central nucleus-nucleus collisions are studied within the hadron-resonance gas model in the canonical ensemble. Exact conservation of three charges, baryon number, electric charge, and strangeness is enforced in the large volume limit. Moments up to the fourth order of various particles are calculated at CERN Super Proton Synchrotron, BNL Relativistic Heavy Ion Collider (RHIC), and CERN Large Hadron Collider energies. The asymptotic fluctuations within a simplified model with only one conserved charge in the canonical ensemble are discussed where simple analytical expressions for moments of multiplicity distributions can be obtained. Moments products of net-proton, net-kaon, and net-charge distributions in Au + Au collisions at RHIC energies are calculated. The pseudorapidity coverage dependence of net-charge fluctuation is discussed.

The Coming Revolutions in Particle Physics

ScienceCinema

Quigg, Chris

2017-12-09

Wonderful opportunities await particle physics over the next decade, with new instruments and experiments poised to explore the frontiers of high energy, infinitesimal distances, and exquisite rarity. We look forward to the Large Hadron Collider at CERN to explore the 1-TeV scale (extending efforts at LEP and the Tevatron to unravel the nature of electroweak symmetry breaking) and many initiatives to develop our understanding of the problem of identity: what makes a neutrino a neutrino and a top quark a top quark. We suspect that the detection of proton decay is only a few orders of magnitude away in sensitivity. Astronomical observations should help to tell us what kinds of matter and energy make up the universe. We might even learn to read experiment for clues about the dimensionality of spacetime. If we are inventive enough, we may be able to follow this rich menu with the physics opportunities offered by a linear electron-positron collider and a (muon storage ring) neutrino factory. I expect a remarkable flowering of experimental particle physics, and of theoretical physics that engages with experiment.

Fabrication Technologies of the High Gradient Accelerator Structures at 100MV/M Range

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Juwen; /SLAC; Lewandowski, James

A CERN-SLAC-KEK collaboration on high gradient X-band structure research has been established in order to demonstrate the feasibility of the CLIC baseline design for the main linac stably operating at more than 100 MV/m loaded accelerating gradient. Several prototype CLIC structures were successfully fabricated and high power tested. They operated at 105 MV/m with a breakdown rate that meets the CLIC linear collider specifications of < 5 x 10{sup -7}/pulse/m. This paper summarizes the fabrication technologies including the mechanical design, precision machining, chemical cleaning, diffusion bonding as well as vacuum baking and all related assembly technologies. Also, the tolerances control,more » tuning and RF characterization will be discussed.« less

Femto-second synchronisation with a waveguide interferometer

NASA Astrophysics Data System (ADS)

Dexter, A. C.; Smith, S. J.; Woolley, B. J.; Grudiev, A.

2018-03-01

CERN's compact linear collider CLIC requires crab cavities on opposing linacs to rotate bunches of particles into alignment at the interaction point (IP). These cavities are located approximately 25 metres either side of the IP. The luminosity target requires synchronisation of their RF phases to better than 5 fs r.m.s. This is to be achieved by powering both cavities from one high power RF source, splitting the power and delivering it along two waveguide paths that are controlled to be identical in length to within a micrometre. The waveguide will be operated as an interferometer. A high power phase shifter for adjusting path lengths has been successfully developed and operated in an interferometer. The synchronisation target has been achieved in a low power prototype system.

A Multi-TeV Linear Collider Based on CLIC Technology : CLIC Conceptual Design Report

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aicheler, M; Burrows, P.; Draper, M.

This report describes the accelerator studies for a future multi-TeV e +e - collider based on the Compact Linear Collider (CLIC) technology. The CLIC concept as described in the report is based on high gradient normal-conducting accelerating structures where the RF power for the acceleration of the colliding beams is extracted from a high-current Drive Beam that runs parallel with the main linac. The focus of CLIC R&D over the last years has been on addressing a set of key feasibility issues that are essential for proving the fundamental validity of the CLIC concept. The status of these feasibility studiesmore » are described and summarized. The report also includes a technical description of the accelerator components and R&D to develop the most important parts and methods, as well as a description of the civil engineering and technical services associated with the installation. Several larger system tests have been performed to validate the two-beam scheme, and of particular importance are the results from the CLIC test facility at CERN (CTF3). Both the machine and detector/physics studies for CLIC have primarily focused on the 3 TeV implementation of CLIC as a benchmark for the CLIC feasibility. This report also includes specific studies for an initial 500 GeV machine, and some discussion of possible intermediate energy stages. The performance and operation issues related to operation at reduced energy compared to the nominal, and considerations of a staged construction program are included in the final part of the report. The CLIC accelerator study is organized as an international collaboration with 43 partners in 22 countries. An associated report describes the physics potential and experiments at CLIC and a shorter report in preparation will focus on the CLIC implementation strategy, together with a plan for the CLIC R&D studies 2012–2016. Critical and important implementation issues such as cost, power and schedule will be addressed there.« less

Signals of doubly-charged Higgsinos at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demir, Durmus A.; Deutsches Elektronen--Synchrotron, DESY, D-22603 Hamburg; Frank, Mariana

2008-08-01

Several supersymmetric models with extended gauge structures, motivated by either grand unification or by neutrino mass generation, predict light doubly-charged Higgsinos. In this work we study productions and decays of doubly-charged Higgsinos present in left-right supersymmetric models, and show that they invariably lead to novel collider signals not found in the minimal supersymmetric model or in any of its extensions motivated by the {mu} problem or even in extra dimensional theories. We investigate their distinctive signatures at the Large Hadron Collider in both pair- and single-production modes, and show that they are powerful tools in determining the underlying model viamore » the measurements at the Large Hadron Collider experiments.« less

CERN at 60: giant magnet journeys through Geneva

NASA Astrophysics Data System (ADS)

Banks, Michael

2014-07-01

More than 30,000 people descended onto Geneva's harbour last month to celebrate the bicentenary of the city's integration into Switzerland with a parade through the city. Joining the 1200 participants at the Genève200 celebrations were staff from the CERN particle-physics lab, which is located on the outskirts of Geneva, who paraded a superconducting dipole magnet - similar to the thousands used in the Large Hadron Collider - through the city's narrow streets on a 20 m lorry.

The Next Linear Collider Program

Science.gov Websites

text only International Study Group (ISG) Meetings NLC Home Page NLC Technical SLAC Eleventh Linear Collider International Study Group at KEK, December 16 - 19, 2003 Tenth (X) Linear Collider International Study Group at SLAC, June, 2003 Nineth Linear Collider ,International Study Group at KEK, December 10-13

Particle Physics after the Higgs-Boson Discovery: Opportunities for the Large Hadron Collider

DOE PAGES

Quigg, Chris

2015-08-24

The first run of the Large Hadron Collider at CERN brought the discovery of the Higgs boson, an apparently elementary scalar particle with a mass of 125 GeV, the avatar of the mechanism that hides the electroweak symmetry. Then, a new round of experimentation is beginning, with the energy of the proton–proton colliding beams raised to 6.5 TeV per beam, from 4 TeV at the end of the first run. I summarize what we have learned about the Higgs boson, and calls attention to some issues that will be among our central concerns in the near future.

Viewpoint: the End of the World at the Large Hadron Collider?

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peskin, Michael E.; /SLAC

New arguments based on astrophysical phenomena constrain the possibility that dangerous black holes will be produced at the CERN Large Hadron Collider. On 8 August, the Large Hadron Collider (LHC) at CERN injected its first beams, beginning an experimental program that will produce proton-proton collisions at an energy of 14 TeV. Particle physicists are waiting expectantly. The reason is that the Standard Model of strong, weak, and electromagnetic interactions, despite its many successes, is clearly incomplete. Theory says that the holes in the model should be filled by new physics in the energy region that will be studied by themore » LHC. Some candidate theories are simple quick fixes, but the most interesting ones involve new concepts of spacetime waiting to be discovered. Look up the LHC on Wikipedia, however, and you will find considerable space devoted to safety concerns. At the LHC, we will probe energies beyond those explored at any previous accelerator, and we hope to create particles that have never been observed. Couldn't we, then, create particles that would actually be dangerous, for example, ones that would eat normal matter and eventually turn the earth into a blob of unpleasantness? It is morbid fun to speculate about such things, and candidates for such dangerous particles have been suggested. These suggestions have been analyzed in an article in Reviews of Modern Physics by Jaffe, Busza, Wilczek, and Sandweiss and excluded on the basis of constraints from observation and from the known laws of physics. These conclusions have been upheld by subsequent studies conducted at CERN.« less

Progress towards next generation hadron colliders: FCC-hh, HE-LHC, and SPPC

NASA Astrophysics Data System (ADS)

Zimmermann, Frank; EuCARD-2 Extreme Beams Collaboration; Future Circular Collider (FCC) Study Collaboration

2017-01-01

A higher-energy circular proton collider is generally considered to be the only path available in this century for exploring energy scales well beyond the reach of the Large Hadron Collider (LHC) presently in operation at CERN. In response to the 2013 Update of the European Strategy for Particle Physics and aligned with the 2014 US ``P5'' recommendations, the international Future Circular Collider (FCC) study, hosted by CERN, is designing such future frontier hadron collider. This so-called FCC-hh will provide proton-proton collisions at a centre-of-mass energy of 100 TeV, with unprecedented luminosity. The FCC-hh energy goal is reached by combining higher-field, 16 T magnets, based on Nb3Sn superconductor, and a new 100 km tunnel connected to the LHC complex. In addition to the FCC-hh proper, the FCC study is also exploring the possibility of a High-Energy LHC (HE-LHC), with a centre-of-mass energy of 25-27 TeV, as could be achieved in the existing 27 km LHC tunnel using the FCC-hh magnet technology. A separate design effort centred at IHEP Beijing aims at developing and constructing a similar collider in China, with a smaller circumference of about 54 km, called SPPC. Assuming even higher-field 20 T magnets, by relying on high-temperature superconductor, the SPPC could reach a c.m. energy of about 70 TeV. This presentation will report the motivation and the present status of the R&D for future hadron colliders, a comparison of the three designs under consideration, the major challenges, R&D topics, the international technology programs, and the emerging global collaboration. Work supported by the European Commission under Capacities 7th Framework Programme project EuCARD-2, Grant Agreement 312453, and the HORIZON 2020 project EuroCirCol, Grant Agreement 654305.

The Education and Outreach Project of ATLAS--A New Participant in Physics Education

ERIC Educational Resources Information Center

Barnett, R. Michael; Johansson, K. Erik

2006-01-01

The ATLAS experiment at the Large Hadron Collider at CERN has a substantial collaborative Education and Outreach project. This article describes its activities and how it promotes physics to students around the world.

Development of an abort gap monitor for the large hadroncollider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Beche, J.-F.; Byrd, J.; De Santis, S.

2004-07-01

The Large Hadron Collider (LHC), presently under construction at CERN, requires monitoring the parasitic charge in the 3.3ms long gap in the machine fill structure. This gap, referred to as the abort gap, corresponds to the raise time of the abort kickers magnets. Any circulating particle present in the abort gap at the time of the kickers firing is lost inside the ring, rather than in the beam dump, and can potentially damage a number of the LHC components. CERN specifications indicate a linear density of 6 x 106 protons over a 100 ns interval as the maximum charge safelymore » allowed to accumulate in the abort gap at 7 TeV. We present a study of an abort gap monitor, based on a photomultiplier tube with a gated microchannel plate, which would allow for detecting such low charge densities by monitoring the synchrotron radiation emitted in the dedicated diagnostics port. We show results of beam test experiments at the Advanced Light Source (ALS) using a Hamamatsu 5961U MCP-PMT, which indicate that such an instrument has the required sensitivity to meet LHC specifications.« less

Construction of a technological semi-digital hadronic calorimeter using GRPC

NASA Astrophysics Data System (ADS)

Laktineh, I.

2011-04-01

A high-granularity semi-digital Hadronic calorimeter using GRPC as sensitive medium is one of the two HCAL options considered by the ILD collaboration to be proposed for the detector of the future International Linear Collider project. A prototype of 1m3 has been conceived within the CALICE collaboration in order to validate this option. The prototype intends to be as close as possible to the one proposed in the ILD Letter Of Intent. Few units made of 1m2 GRPC fully equipped with semi-digital readout electronics and new gas distribution design were produced and successfully tested. In 2010 we intend to produce 40 similar units to be inserted in a self-supporting mechanical structure. The prototype will then be exposed to TestBeams at CERN for final validation.

Black Holes and the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Roy, Arunava

2011-12-01

The European Center for Nuclear Research or CERN's Large Hadron Collider (LHC) has caught our attention partly due to the film ``Angels and Demons.'' In the movie, an antimatter bomb attack on the Vatican is foiled by the protagonist. Perhaps just as controversial is the formation of mini black holes (BHs). Recently, the American Physical Society1 website featured an article on BH formation at the LHC.2 This article examines some aspects of mini BHs and explores the possibility of their detection at the LHC.

Direct photon elliptic flow at energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Kim, Young-Min; Lee, Chang-Hwan; Teaney, Derek; Zahed, Ismail

2017-07-01

We use an event-by-event hydrodynamical description of the heavy-ion collision process with Glauber initial conditions to calculate the thermal emission of photons. The photon rates in the hadronic phase follow from a spectral function approach and a density expansion, while in the partonic phase they follow from the Arnold-Moore-Yaffe (AMY) perturbative rates. The calculated photon elliptic flows are lower than those reported recently by both the ALICE and PHENIX collaborations.

Collider and Detector Protection at Beam Accidents

NASA Astrophysics Data System (ADS)

Rakhno, I. L.; Mokhov, N. V.; Drozhdin, A. I.

2003-12-01

Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occured at Tevatron (Fermilab) during Run I and Run II are analyzed and a protection system implemented is described. The effect of accidental beam loss in the Large Hadron Collider (LHC) at CERN on machine and detector components is studied via realistic Monte Carlo calculations. The simulations show that beam loss at an unsynchronized beam abort would result in severe heating of conventional and superconducting magnets and possible damage to the collider detector elements. A proposed set of collimators would reduce energy deposition effects to acceptable levels. Special attention is paid to reducing peak temperature rise within the septum magnet and minimizing quench region length downstream of the LHC beam abort straight section.

High duty factor plasma generator for CERN's Superconducting Proton Linac.

PubMed

Lettry, J; Kronberger, M; Scrivens, R; Chaudet, E; Faircloth, D; Favre, G; Geisser, J-M; Küchler, D; Mathot, S; Midttun, O; Paoluzzi, M; Schmitzer, C; Steyaert, D

2010-02-01

CERN's Linac4 is a 160 MeV linear accelerator currently under construction. It will inject negatively charged hydrogen ions into CERN's PS-Booster. Its ion source is a noncesiated rf driven H(-) volume source directly inspired from the one of DESY and is aimed to deliver pulses of 80 mA of H(-) during 0.4 ms at a 2 Hz repetition rate. The Superconducting Proton Linac (SPL) project is part of the luminosity upgrade of the Large Hadron Collider. It consists of an extension of Linac4 up to 5 GeV and is foreseen to deliver protons to a future 50 GeV synchrotron (PS2). For the SPL high power option (HP-SPL), the ion source would deliver pulses of 80 mA of H(-) during 1.2 ms and operate at a 50 Hz repetition rate. This significant upgrade motivates the design of the new water cooled plasma generator presented in this paper. Its engineering is based on the results of a finite element thermal study of the Linac4 H(-) plasma generator that identified critical components and thermal barriers. A cooling system is proposed which achieves the required heat dissipation and maintains the original functionality. Materials with higher thermal conductivity are selected and, wherever possible, thermal barriers resulting from low pressure contacts are removed by brazing metals on insulators. The AlN plasma chamber cooling circuit is inspired from the approach chosen for the cesiated high duty factor rf H(-) source operating at SNS.

Big Bang Day: Engineering Solutions

ScienceCinema

None

2017-12-09

CERN's Large Hadron Collider is the most complicated scientific apparatus ever built. Many of the technologies it uses hadn't even been invented when scientists started building it. Adam Hart-Davis discovers what it takes to build the world's most intricate discovery machine.

Intense beams at the micron level for the Next Linear Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seeman, J.T.

1991-08-01

High brightness beams with sub-micron dimensions are needed to produce a high luminosity for electron-positron collisions in the Next Linear Collider (NLC). To generate these small beam sizes, a large number of issues dealing with intense beams have to be resolved. Over the past few years many have been successfully addressed but most need experimental verification. Some of these issues are beam dynamics, emittance control, instrumentation, collimation, and beam-beam interactions. Recently, the Stanford Linear Collider (SLC) has proven the viability of linear collider technology and is an excellent test facility for future linear collider studies.

The Next Linear Collider Program

Science.gov Websites

The Next Linear Collider at SLAC Navbar NLC Playpen Warning: This page is provided as a place for Comments & Suggestions | Desktop Trouble Call | Linear Collider Group at FNAL || This page was updated

LHC@Home: a BOINC-based volunteer computing infrastructure for physics studies at CERN

NASA Astrophysics Data System (ADS)

Barranco, Javier; Cai, Yunhai; Cameron, David; Crouch, Matthew; Maria, Riccardo De; Field, Laurence; Giovannozzi, Massimo; Hermes, Pascal; Høimyr, Nils; Kaltchev, Dobrin; Karastathis, Nikos; Luzzi, Cinzia; Maclean, Ewen; McIntosh, Eric; Mereghetti, Alessio; Molson, James; Nosochkov, Yuri; Pieloni, Tatiana; Reid, Ivan D.; Rivkin, Lenny; Segal, Ben; Sjobak, Kyrre; Skands, Peter; Tambasco, Claudia; Veken, Frederik Van der; Zacharov, Igor

2017-12-01

The LHC@Home BOINC project has provided computing capacity for numerical simulations to researchers at CERN since 2004, and has since 2011 been expanded with a wider range of applications. The traditional CERN accelerator physics simulation code SixTrack enjoys continuing volunteers support, and thanks to virtualisation a number of applications from the LHC experiment collaborations and particle theory groups have joined the consolidated LHC@Home BOINC project. This paper addresses the challenges related to traditional and virtualized applications in the BOINC environment, and how volunteer computing has been integrated into the overall computing strategy of the laboratory through the consolidated LHC@Home service. Thanks to the computing power provided by volunteers joining LHC@Home, numerous accelerator beam physics studies have been carried out, yielding an improved understanding of charged particle dynamics in the CERN Large Hadron Collider (LHC) and its future upgrades. The main results are highlighted in this paper.

Exploring the BWCA (Bino-Wino co-annihilation) scenario for neutralino dark matter

NASA Astrophysics Data System (ADS)

Baer, Howard; Krupovnickas, Tadas; Mustafayev, Azar; Park, Eun-Kyung; Profumo, Stefano; Tata, Xerxes

2005-12-01

In supersymmetric models with non-universal gaugino masses, it is possible to have opposite-sign SU(2) and U(1) gaugino mass terms. In these models, the gaugino eigenstates experience little mixing so that the lightest SUSY particle remains either pure bino or pure wino. The neutralino relic density can only be brought into accord with the WMAP measured value when bino-wino co-annihilation (BWCA) acts to enhance the dark matter annihilation rate. We map out parameter space regions and mass spectra which are characteristic of the BWCA scenario. Direct and indirect dark matter detection rates are shown to be typically very low. At collider experiments, the BWCA scenario is typified by a small mass gap mtilde Z2-mtilde Z1 ~ 20-80 GeV, so that tree level two body decays of tilde Z2 are not allowed. However, in this case the second lightest neutralino has an enhanced loop decay branching fraction to photons. While the photonic neutralino decay signature looks difficult to extract at the Fermilab Tevatron, it should lead to distinctive events at the CERN LHC and at a linear e+e- collider.

High baryon densities in heavy ion collisions at energies attainable at the BNL Relativistic Heavy-Ion Collider and the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Li, Ming; Kapusta, Joseph I.

2017-01-01

In very high-energy collisions nuclei are practically transparent to each other but produce very hot nearly baryon-free matter in the so-called central rapidity region. The energy in the central rapidity region comes from the kinetic energy of the colliding nuclei. We calculate the energy and rapidity loss of the nuclei using the color glass condensate model. This model also predicts the excitation energy of the nuclear fragments. Using a space-time picture of the collision we calculate the baryon and energy densities of the receding baryonic fireballs. For central collisions of gold nuclei at the highest energy attainable at the Relativistic Heavy-Ion Collider, for example, we find baryon densities more than ten times that of atomic nuclei over a large volume.

Phenomenology of the SU(3)_c⊗ SU(3)_L⊗ U(1)_X model with right-handed neutrinos

NASA Astrophysics Data System (ADS)

Gutiérrez, D. A.; Ponce, W. A.; Sánchez, L. A.

2006-05-01

A phenomenological analysis of the three-family model based on the local gauge group SU(3)_c⊗ SU(3)_L⊗ U(1)_X with right-handed neutrinos is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produces a quark mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions for achieving a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model.

Phenomenology of the SU(3)c⊗SU(3)L⊗U(1)X model with exotic charged leptons

NASA Astrophysics Data System (ADS)

Salazar, Juan C.; Ponce, William A.; Gutiérrez, Diego A.

2007-04-01

A phenomenological analysis of the three-family model based on the local gauge group SU(3)c⊗SU(3)L⊗U(1)X with exotic charged leptons, is carried out. Instead of using the minimal scalar sector able to break the symmetry in a proper way, we introduce an alternative set of four Higgs scalar triplets, which combined with an anomaly-free discrete symmetry, produce quark and charged lepton mass spectrum without hierarchies in the Yukawa coupling constants. We also embed the structure into a simple gauge group and show some conditions to achieve a low energy gauge coupling unification, avoiding possible conflict with proton decay bounds. By using experimental results from the CERN-LEP, SLAC linear collider, and atomic parity violation data, we update constraints on several parameters of the model.

WW Physics at Future e{sup +}e{sup -} Linear Colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barklow, Timothy L

Measurements of triple gauge boson couplings and strong electroweak symmetry breaking effects at future e{sup +}e{sup -} linear colliders are reviewed. The results expected from a future e{sup +}e{sup -} linear collider are compared with LHC expectations.

Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cullinan, F. J.; Boogert, S. T.; Farabolini, W.

2015-11-19

The Compact Linear Collider (CLIC) requires beam position monitors (BPMs) with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3) at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the referencemore » cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2/3 ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Lastly, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.« less

Long bunch trains measured using a prototype cavity beam position monitor for the Compact Linear Collider

NASA Astrophysics Data System (ADS)

Cullinan, F. J.; Boogert, S. T.; Farabolini, W.; Lefevre, T.; Lunin, A.; Lyapin, A.; Søby, L.; Towler, J.; Wendt, M.

2015-11-01

The Compact Linear Collider (CLIC) requires beam position monitors (BPMs) with 50 nm spatial resolution for alignment of the beam line elements in the main linac and beam delivery system. Furthermore, the BPMs must be able to make multiple independent measurements within a single 156 ns long bunch train. A prototype cavity BPM for CLIC has been manufactured and tested on the probe beam line at the 3rd CLIC Test Facility (CTF3) at CERN. The transverse beam position is determined from the electromagnetic resonant modes excited by the beam in the two cavities of the pickup, the position cavity and the reference cavity. The mode that is measured in each cavity resonates at 15 GHz and has a loaded quality factor that is below 200. Analytical expressions for the amplitude, phase and total energy of signals from long trains of bunches have been derived and the main conclusions are discussed. The results of the beam tests are presented. The variable gain of the receiver electronics has been characterized using beam excited signals and the form of the signals for different beam pulse lengths with the 2 /3 ns bunch spacing has been observed. The sensitivity of the reference cavity signal to charge and the horizontal position signal to beam offset have been measured and are compared with theoretical predictions based on laboratory measurements of the BPM pickup and the form of the resonant cavity modes as determined by numerical simulation. Finally, the BPM was calibrated so that the beam position jitter at the BPM location could be measured. It is expected that the beam jitter scales linearly with the beam size and so the results are compared to predicted values for the latter.

The LHCb Detector at the LHC

NASA Astrophysics Data System (ADS)

LHCb Collaboration; Alves, A. Augusto, Jr.; Filho, L. M. Andrade; Barbosa, A. F.; Bediaga, I.; Cernicchiaro, G.; Guerrer, G.; Lima, H. P., Jr.; Machado, A. A.; Magnin, J.; Marujo, F.; de Miranda, J. M.; Reis, A.; Santos, A.; Toledo, A.; Akiba, K.; Amato, S.; de Paula, B.; de Paula, L.; da Silva, T.; Gandelman, M.; Lopes, J. H.; Maréchal, B.; Moraes, D.; Polycarpo, E.; Rodrigues, F.; Ballansat, J.; Bastian, Y.; Boget, D.; DeBonis, I.; Coco, V.; David, P. Y.; Decamp, D.; Delebecque, P.; Drancourt, C.; Dumont-Dayot, N.; Girard, C.; Lieunard, B.; Minard, M. N.; Pietrzyk, B.; Rambure, T.; Rospabe, G.; T'Jampens, S.; Ajaltouni, Z.; Bohner, G.; Bonnefoy, R.; Borras, D.; Carloganu, C.; Chanal, H.; Conte, E.; Cornat, R.; Crouau, M.; Delage, E.; Deschamps, O.; Henrard, P.; Jacquet, P.; Lacan, C.; Laubser, J.; Lecoq, J.; Lefèvre, R.; Magne, M.; Martemiyanov, M.; Mercier, M.-L.; Monteil, S.; Niess, V.; Perret, P.; Reinmuth, G.; Robert, A.; Suchorski, S.; Arnaud, K.; Aslanides, E.; Babel, J.; Benchouk, C.; Cachemiche, J.-P.; Cogan, J.; Derue, F.; Dinkespiler, B.; Duval, P.-Y.; Garonne, V.; Favard, S.; LeGac, R.; Leon, F.; Leroy, O.; Liotard, P.-L.; Marin, F.; Menouni, M.; Ollive, P.; Poss, S.; Roche, A.; Sapunov, M.; Tocco, L.; Viaud, B.; Tsaregorodtsev, A.; Amhis, Y.; Barrand, G.; Barsuk, S.; Beigbeder, C.; Beneyton, R.; Breton, D.; Callot, O.; Charlet, D.; D'Almagne, B.; Duarte, O.; Fulda-Quenzer, F.; Jacholkowska, A.; Jean-Marie, B.; Lefrancois, J.; Machefert, F.; Robbe, P.; Schune, M.-H.; Tocut, V.; Videau, I.; Benayoun, M.; David, P.; DelBuono, L.; Gilles, G.; Domke, M.; Futterschneider, H.; Ilgner, Ch; Kapusta, P.; Kolander, M.; Krause, R.; Lieng, M.; Nedos, M.; Rudloff, K.; Schleich, S.; Schwierz, R.; Spaan, B.; Wacker, K.; Warda, K.; Agari, M.; Bauer, C.; Baumeister, D.; Bulian, N.; Fuchs, H. P.; Fallot-Burghardt, W.; Glebe, T.; Hofmann, W.; Knöpfle, K. T.; Löchner, S.; Ludwig, A.; Maciuc, F.; Sanchez Nieto, F.; Schmelling, M.; Schwingenheuer, B.; Sexauer, E.; Smale, N. J.; Trunk, U.; Voss, H.; Albrecht, J.; Bachmann, S.; Blouw, J.; Deissenroth, M.; Deppe, H.; Dreis, H. B.; Eisele, F.; Haas, T.; Hansmann-Menzemer, S.; Hennenberger, S.; Knopf, J.; Moch, M.; Perieanu, A.; Rabenecker, S.; Rausch, A.; Rummel, C.; Rusnyak, R.; Schiller, M.; Stange, U.; Uwer, U.; Walter, M.; Ziegler, R.; Avoni, G.; Balbi, G.; Bonifazi, F.; Bortolotti, D.; Carbone, A.; D'Antone, I.; Galli, D.; Gregori, D.; Lax, I.; Marconi, U.; Peco, G.; Vagnoni, V.; Valenti, G.; Vecchi, S.; Bonivento, W.; Cardini, A.; Cadeddu, S.; DeLeo, V.; Deplano, C.; Furcas, S.; Lai, A.; Oldeman, R.; Raspino, D.; Saitta, B.; Serra, N.; Baldini, W.; Brusa, S.; Chiozzi, S.; Cotta Ramusino, A.; Evangelisti, F.; Franconieri, A.; Germani, S.; Gianoli, A.; Guoming, L.; Landi, L.; Malaguti, R.; Padoan, C.; Pennini, C.; Savriè, M.; Squerzanti, S.; Zhao, T.; Zhu, M.; Bizzeti, A.; Graziani, G.; Lenti, M.; Lenzi, M.; Maletta, F.; Pennazzi, S.; Passaleva, G.; Veltri, M.; Alfonsi, M.; Anelli, M.; Balla, A.; Battisti, A.; Bencivenni, G.; Campana, P.; Carletti, M.; Ciambrone, P.; Corradi, G.; Dané, E.; Di Virgilio, A.; DeSimone, P.; Felici, G.; Forti, C.; Gatta, M.; Lanfranchi, G.; Murtas, F.; Pistilli, M.; Poli Lener, M.; Rosellini, R.; Santoni, M.; Saputi, A.; Sarti, A.; Sciubba, A.; Zossi, A.; Ameri, M.; Cuneo, S.; Fontanelli, F.; Gracco, V.; Miní, G.; Parodi, M.; Petrolini, A.; Sannino, M.; Vinci, A.; Alemi, M.; Arnaboldi, C.; Bellunato, T.; Calvi, M.; Chignoli, F.; DeLucia, A.; Galotta, G.; Mazza, R.; Matteuzzi, C.; Musy, M.; Negri, P.; Perego, D.; Pessina, G.; Auriemma, G.; Bocci, V.; Buccheri, A.; Chiodi, G.; Di Marco, S.; Iacoangeli, F.; Martellotti, G.; Nobrega, R.; Pelosi, A.; Penso, G.; Pinci, D.; Rinaldi, W.; Rossi, A.; Santacesaria, R.; Satriano, C.; Carboni, G.; Iannilli, M.; Massafferri Rodrigues, A.; Messi, R.; Paoluzzi, G.; Sabatino, G.; Santovetti, E.; Satta, A.; Amoraal, J.; van Apeldoorn, G.; Arink, R.; van Bakel, N.; Band, H.; Bauer, Th; Berkien, A.; van Beuzekom, M.; Bos, E.; Bron, Ch; Ceelie, L.; Doets, M.; van der Eijk, R.; Fransen, J.-P.; de Groen, P.; Gromov, V.; Hierck, R.; Homma, J.; Hommels, B.; Hoogland, W.; Jans, E.; Jansen, F.; Jansen, L.; Jaspers, M.; Kaan, B.; Koene, B.; Koopstra, J.; Kroes, F.; Kraan, M.; Langedijk, J.; Merk, M.; Mos, S.; Munneke, B.; Palacios, J.; Papadelis, A.; Pellegrino, A.; van Petten, O.; du Pree, T.; Roeland, E.; Ruckstuhl, W.; Schimmel, A.; Schuijlenburg, H.; Sluijk, T.; Spelt, J.; Stolte, J.; Terrier, H.; Tuning, N.; Van Lysebetten, A.; Vankov, P.; Verkooijen, J.; Verlaat, B.; Vink, W.; de Vries, H.; Wiggers, L.; Ybeles Smit, G.; Zaitsev, N.; Zupan, M.; Zwart, A.; van den Brand, J.; Bulten, H. J.; de Jong, M.; Ketel, T.; Klous, S.; Kos, J.; M'charek, B.; Mul, F.; Raven, G.; Simioni, E.; Cheng, J.; Dai, G.; Deng, Z.; Gao, Y.; Gong, G.; Gong, H.; He, J.; Hou, L.; Li, J.; Qian, W.; Shao, B.; Xue, T.; Yang, Z.; Zeng, M.; Muryn, B.; Ciba, K.; Oblakowska-Mucha, A.; Blocki, J.; Galuszka, K.; Hajduk, L.; Michalowski, J.; Natkaniec, Z.; Polok, G.; Stodulski, M.; Witek, M.; Brzozowski, K.; Chlopik, A.; Gawor, P.; Guzik, Z.; Nawrot, A.; Srednicki, A.; Syryczynski, K.; Szczekowski, M.; Anghel, D. V.; Cimpean, A.; Coca, C.; Constantin, F.; Cristian, P.; Dumitru, D. D.; Dumitru, D. T.; Giolu, G.; Kusko, C.; Magureanu, C.; Mihon, Gh; Orlandea, M.; Pavel, C.; Petrescu, R.; Popescu, S.; Preda, T.; Rosca, A.; Rusu, V. L.; Stoica, R.; Stoica, S.; Tarta, P. D.; Filippov, S.; Gavrilov, Yu; Golyshkin, L.; Gushchin, E.; Karavichev, O.; Klubakov, V.; Kravchuk, L.; Kutuzov, V.; Laptev, S.; Popov, S.; Aref'ev, A.; Bobchenko, B.; Dolgoshein, V.; Egorychev, V.; Golutvin, A.; Gushchin, O.; Konoplyannikov, A.; Korolko, I.; Kvaratskheliya, T.; Machikhiliyan, I.; Malyshev, S.; Mayatskaya, E.; Prokudin, M.; Rusinov, D.; Rusinov, V.; Shatalov, P.; Shchutska, L.; Tarkovskiy, E.; Tayduganov, A.; Voronchev, K.; Zhiryakova, O.; Bobrov, A.; Bondar, A.; Eidelman, S.; Kozlinsky, A.; Shekhtman, L.; Beloous, K. S.; Dzhelyadin, R. I.; Gelitsky, Yu V.; Gouz, Yu P.; Kachnov, K. G.; Kobelev, A. S.; Matveev, V. D.; Novikov, V. P.; Obraztsov, V. F.; Ostankov, A. P.; Romanovsky, V. I.; Rykalin, V. I.; Soldatov, A. P.; Soldatov, M. M.; Tchernov, E. N.; Yushchenko, O. P.; Bochin, B.; Bondar, N.; Fedorov, O.; Golovtsov, V.; Guets, S.; Kashchuk, A.; Lazarev, V.; Maev, O.; Neustroev, P.; Sagidova, N.; Spiridenkov, E.; Volkov, S.; Vorobyev, An; Vorobyov, A.; Aguilo, E.; Bota, S.; Calvo, M.; Comerma, A.; Cano, X.; Dieguez, A.; Herms, A.; Lopez, E.; Luengo, S.; Garra, J.; Garrido, Ll; Gascon, D.; Gaspar de Valenzuela, A.; Gonzalez, C.; Graciani, R.; Grauges, E.; Perez Calero, A.; Picatoste, E.; Riera, J.; Rosello, M.; Ruiz, H.; Vilasis, X.; Xirgu, X.; Adeva, B.; Cid Vidal, X.; MartÉnez Santos, D.; Esperante Pereira, D.; Fungueiriño Pazos, J. L.; Gallas Torreira, A.; Gómez, C. Lois; Pazos Alvarez, A.; Pérez Trigo, E.; Pló Casasús, M.; Rodriguez Cobo, C.; Rodríguez Pérez, P.; Saborido, J. J.; Seco, M.; Vazquez Regueiro, P.; Bartalini, P.; Bay, A.; Bettler, M.-O.; Blanc, F.; Borel, J.; Carron, B.; Currat, C.; Conti, G.; Dormond, O.; Ermoline, Y.; Fauland, P.; Fernandez, L.; Frei, R.; Gagliardi, G.; Gueissaz, N.; Haefeli, G.; Hicheur, A.; Jacoby, C.; Jalocha, P.; Jimenez-Otero, S.; Hertig, J.-P.; Knecht, M.; Legger, F.; Locatelli, L.; Moser, J.-R.; Needham, M.; Nicolas, L.; Perrin-Giacomin, A.; Perroud, J.-P.; Potterat, C.; Ronga, F.; Schneider, O.; Schietinger, T.; Steele, D.; Studer, L.; Tareb, M.; Tran, M. T.; van Hunen, J.; Vervink, K.; Villa, S.; Zwahlen, N.; Bernet, R.; Büchler, A.; Gassner, J.; Lehner, F.; Sakhelashvili, T.; Salzmann, C.; Sievers, P.; Steiner, S.; Steinkamp, O.; Straumann, U.; van Tilburg, J.; Vollhardt, A.; Volyanskyy, D.; Ziegler, M.; Dovbnya, A.; Ranyuk, Yu; Shapoval, I.; Borisova, M.; Iakovenko, V.; Kyva, V.; Kovalchuk, O.; Okhrimenko, O.; Pugatch, V.; Pylypchenko, Yu; Adinolfi, M.; Brook, N. H.; Head, R. D.; Imong, J. P.; Lessnoff, K. A.; Metlica, F. C. D.; Muir, A. J.; Rademacker, J. H.; Solomin, A.; Szczypka, P. M.; Barham, C.; Buszello, C.; Dickens, J.; Gibson, V.; Haines, S.; Harrison, K.; Jones, C. R.; Katvars, S.; Kerzel, U.; Lazzeroni, C.; Li, Y. Y.; Rogers, G.; Storey, J.; Skottowe, H.; Wotton, S. A.; Adye, T. J.; Densham, C. J.; Easo, S.; Franek, B.; Loveridge, P.; Morrow, D.; Morris, J. V.; Nandakumar, R.; Nardulli, J.; Papanestis, A.; Patrick, G. N.; Ricciardi, S.; Woodward, M. L.; Zhang, Z.; Chamonal, R. J. U.; Clark, P. J.; Clarke, P.; Eisenhardt, S.; Gilardi, N.; Khan, A.; Kim, Y. M.; Lambert, R.; Lawrence, J.; Main, A.; McCarron, J.; Mclean, C.; Muheim, F.; Osorio-Oliveros, A. F.; Playfer, S.; Styles, N.; Xie, Y.; Bates, A.; Carson, L.; da Cunha Marinho, F.; Doherty, F.; Eklund, L.; Gersabeck, M.; Haddad, L.; Macgregor, A. A.; Melone, J.; McEwan, F.; Petrie, D. M.; Paterson, S. K.; Parkes, C.; Pickford, A.; Rakotomiaramanana, B.; Rodrigues, E.; Saavedra, A. F.; Soler, F. J. P.; Szumlak, T.; Viret, S.; Allebone, L.; Awunor, O.; Back, J.; Barber, G.; Barnes, C.; Cameron, B.; Clark, D.; Clark, I.; Dornan, P.; Duane, A.; Eames, C.; Egede, U.; Girone, M.; Greenwood, S.; Hallam, R.; Hare, R.; Howard, A.; Jolly, S.; Kasey, V.; Khaleeq, M.; Koppenburg, P.; Miller, D.; Plackett, R.; Price, D.; Reece, W.; Savage, P.; Savidge, T.; Simmons, B.; Vidal-Sitjes, G.; Websdale, D.; Affolder, A.; Anderson, J. S.; Biagi, S. F.; Bowcock, T. J. V.; Carroll, J. L.; Casse, G.; Cooke, P.; Donleavy, S.; Dwyer, L.; Hennessy, K.; Huse, T.; Hutchcroft, D.; Jones, D.; Lockwood, M.; McCubbin, M.; McNulty, R.; Muskett, D.; Noor, A.; Patel, G. D.; Rinnert, K.; Shears, T.; Smith, N. A.; Southern, G.; Stavitski, I.; Sutcliffe, P.; Tobin, M.; Traynor, S. M.; Turner, P.; Whitley, M.; Wormald, M.; Wright, V.; Bibby, J. H.; Brisbane, S.; Brock, M.; Charles, M.; Cioffi, C.; Gligorov, V. V.; Handford, T.; Harnew, N.; Harris, F.; John, M. J. J.; Jones, M.; Libby, J.; Martin, L.; McArthur, I. A.; Muresan, R.; Newby, C.; Ottewell, B.; Powell, A.; Rotolo, N.; Senanayake, R. S.; Somerville, L.; Soroko, A.; Spradlin, P.; Sullivan, P.; Stokes-Rees, I.; Topp-Jorgensen, S.; Xing, F.; Wilkinson, G.; Artuso, M.; Belyaev, I.; Blusk, S.; Lefeuvre, G.; Menaa, N.; Menaa-Sia, R.; Mountain, R.; Skwarnicki, T.; Stone, S.; Wang, J. C.; Abadie, L.; Aglieri-Rinella, G.; Albrecht, E.; André, J.; Anelli, G.; Arnaud, N.; Augustinus, A.; Bal, F.; Barandela Pazos, M. C.; Barczyk, A.; Bargiotti, M.; Batista Lopes, J.; Behrendt, O.; Berni, S.; Binko, P.; Bobillier, V.; Braem, A.; Brarda, L.; Buytaert, J.; Camilleri, L.; Cambpell, M.; Castellani, G.; Cataneo, F.; Cattaneo, M.; Chadaj, B.; Charpentier, P.; Cherukuwada, S.; Chesi, E.; Christiansen, J.; Chytracek, R.; Clemencic, M.; Closier, J.; Collins, P.; Colrain, P.; Cooke, O.; Corajod, B.; Corti, G.; D'Ambrosio, C.; Damodaran, B.; David, C.; de Capua, S.; Decreuse, G.; Degaudenzi, H.; Dijkstra, H.; Droulez, J.-P.; Duarte Ramos, D.; Dufey, J. P.; Dumps, R.; Eckstein, D.; Ferro-Luzzi, M.; Fiedler, F.; Filthaut, F.; Flegel, W.; Forty, R.; Fournier, C.; Frank, M.; Frei, C.; Gaidioz, B.; Gaspar, C.; Gayde, J.-C.; Gavillet, P.; Go, A.; Gracia Abril, G.; Graulich, J.-S.; Giudici, P.-A.; Guirao Elias, A.; Guglielmini, P.; Gys, T.; Hahn, F.; Haider, S.; Harvey, J.; Hay, B.; Hernando Morata, J.-A.; Herranz Alvarez, J.; van Herwijnen, E.; Hilke, H. J.; von Holtey, G.; Hulsbergen, W.; Jacobsson, R.; Jamet, O.; Joram, C.; Jost, B.; Kanaya, N.; Knaster Refolio, J.; Koestner, S.; Koratzinos, M.; Kristic, R.; Lacarrère, D.; Lasseur, C.; Lastovicka, T.; Laub, M.; Liko, D.; Lippmann, C.; Lindner, R.; Losasso, M.; Maier, A.; Mair, K.; Maley, P.; Mato Vila, P.; Moine, G.; Morant, J.; Moritz, M.; Moscicki, J.; Muecke, M.; Mueller, H.; Nakada, T.; Neufeld, N.; Ocariz, J.; Padilla Aranda, C.; Parzefall, U.; Patel, M.; Pepe-Altarelli, M.; Piedigrossi, D.; Pivk, M.; Pokorski, W.; Ponce, S.; Ranjard, F.; Riegler, W.; Renaud, J.; Roiser, S.; Rossi, A.; Roy, L.; Ruf, T.; Ruffinoni, D.; Saladino, S.; Sambade Varela, A.; Santinelli, R.; Schmelling, S.; Schmidt, B.; Schneider, T.; Schöning, A.; Schopper, A.; Seguinot, J.; Snoeys, W.; Smith, A.; Smith, A. C.; Somogyi, P.; Stoica, R.; Tejessy, W.; Teubert, F.; Thomas, E.; Toledo Alarcon, J.; Ullaland, O.; Valassi, A.; Vannerem, P.; Veness, R.; Wicht, P.; Wiedner, D.; Witzeling, W.; Wright, A.; Wyllie, K.; Ypsilantis, T.

2008-08-01

The LHCb experiment is dedicated to precision measurements of CP violation and rare decays of B hadrons at the Large Hadron Collider (LHC) at CERN (Geneva). The initial configuration and expected performance of the detector and associated systems, as established by test beam measurements and simulation studies, is described.

Simultaneous production of lepton pairs in ultraperipheral relativistic heavy ion collisions

NASA Astrophysics Data System (ADS)

Kurban, E.; Güçlü, M. C.

2017-10-01

We calculate the total cross sections and probabilities of electromagnetic productions of electron, muon, and tauon pairs simultaneously. At the CERN Large Hadron Collider (LHC), the available electromagnetic energy is sufficient to produce all kinds of leptons coherently. The masses of muons and tauons are large, so their Compton wavelengths are small enough to interact with the colliding nuclei. Therefore, the realistic nuclear form factors are included in the calculations of electromagnetic pair productions. The cross section calculations show that, at LHC energies, the probabilities of simultaneous productions of all kinds of leptons are increased significantly compared to energies available at the BNL Relativistic Heavy Ion Collider (RHIC) . Experimentally, observing this simultaneous production can give us important information about strong QED.

Observations of beam losses due to bound-free pair production in a heavy-ion collider.

PubMed

Bruce, R; Jowett, J M; Gilardoni, S; Drees, A; Fischer, W; Tepikian, S; Klein, S R

2007-10-05

We report the first observations of beam losses due to bound-free pair production at the interaction point of a heavy-ion collider. This process is expected to be a major luminosity limit for the CERN Large Hadron Collider when it operates with (208)Pb(82+) ions because the localized energy deposition by the lost ions may quench superconducting magnet coils. Measurements were performed at the BNL Relativistic Heavy Ion Collider (RHIC) during operation with 100 GeV/nucleon (63)Cu(29+) ions. At RHIC, the rate, energy and magnetic field are low enough so that magnet quenching is not an issue. The hadronic showers produced when the single-electron ions struck the RHIC beam pipe were observed using an array of photodiodes. The measurement confirms the order of magnitude of the theoretical cross section previously calculated by others.

Anomalous single production of the fourth generation quarks at the CERN LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ciftci, R.

Possible anomalous single productions of the fourth standard model generation up and down type quarks at CERN Large Hadron Collider are studied. Namely, pp{yields}u{sub 4}(d{sub 4})X with subsequent u{sub 4}{yields}bW{sup +} process followed by the leptonic decay of the W boson and d{sub 4}{yields}b{gamma} (and its H.c.) decay channel are considered. Signatures of these processes and corresponding standard model backgrounds are discussed in detail. Discovery limits for the quark mass and achievable values of the anomalous coupling strength are determined.

Data acquisition using the 168/E. [CERN ISR

DOE Office of Scientific and Technical Information (OSTI.GOV)

Carroll, J.T.; Cittolin, S.; Demoulin, M.

1983-03-01

Event sizes and data rates at the CERN anti p p collider compose a formidable environment for a high level trigger. A system using three 168/E processors for experiment UA1 real-time event selection is described. With 168/E data memory expanded to 512K bytes, each processor holds a complete event allowing a FORTRAN trigger algorithm access to data from the entire detector. A smart CAMAC interface reads five Remus branches in parallel transferring one word to the target processor every 0.5 ..mu..s. The NORD host computer can simultaneously read an accepted event from another processor.

U.S. Involvement in the LHC

DOE PAGES

Green, Dan

2016-12-14

The demise of the SSC in the U.S. created an upheaval in the U.S. high energy physics (HEP) community. Here, the subsequent redirection of HEP efforts to the CERN Large Hadron Collider (LHC) can perhaps be seen as informing on possible future paths for worldwide collaboration on future HEP megaprojects.

Bounds on the nonminimal coupling of the Higgs boson to gravity.

PubMed

Atkins, Michael; Calmet, Xavier

2013-02-01

We derive the first bound on the value of the Higgs boson nonminimal coupling to the Ricci scalar. We show that the recent discovery of the Higgs boson at the Large Hadron Collider at CERN implies that the nonminimal coupling is smaller than 2.6×10(15).

Observation of genetic relation among new phenomena Geminion, Chiron and mini-Centauro

NASA Technical Reports Server (NTRS)

1985-01-01

The threshold energy problem of exotic type interactions is discussed on the basis of available information from the Chacaltaya emulsion chamber experiment. The genetic hypothesis is proposed as a working hypothesis to explain the discrepancy seen in cosmic ray study and CERN p bar -p collider experiments.

Thermostructural characterization and structural elastic property optimization of novel high luminosity LHC collimation materials at CERN

NASA Astrophysics Data System (ADS)

Borg, M.; Bertarelli, A.; Carra, F.; Gradassi, P.; Guardia-Valenzuela, J.; Guinchard, M.; Izquierdo, G. Arnau; Mollicone, P.; Sacristan-de-Frutos, O.; Sammut, N.

2018-03-01

The CERN Large Hadron Collider is currently being upgraded to operate at a stored beam energy of 680 MJ through the High Luminosity upgrade. The LHC performance is dependent on the functionality of beam collimation systems, essential for safe beam cleaning and machine protection. A dedicated beam experiment at the CERN High Radiation to Materials facility is created under the HRMT-23 experimental campaign. This experiment investigates the behavior of three collimation jaws having novel composite absorbers made of copper diamond, molybdenum carbide graphite, and carbon fiber carbon, experiencing accidental scenarios involving the direct beam impact on the material. Material characterization is imperative for the design, execution, and analysis of such experiments. This paper presents new data and analysis of the thermostructural characteristics of some of the absorber materials commissioned within CERN facilities. In turn, characterized elastic properties are optimized through the development and implementation of a mixed numerical-experimental optimization technique.

Luminosity Limitations of Linear Colliders Based on Plasma Acceleration

DOE PAGES

Lebedev, Valeri; Burov, Alexey; Nagaitsev, Sergei

2016-01-01

Particle acceleration in plasma creates a possibility of exceptionally high accelerating gradients and appears as a very attractive option for future linear electron-positron and/or photon-photon colliders. These high accelerating gradients were already demonstrated in a number of experiments. Furthermore, a linear collider requires exceptionally high beam brightness which still needs to be demonstrated. In this article we discuss major phenomena which limit the beam brightness of accelerated beam and, consequently, the collider luminosity.

The Higgs mechanism and the origin of mass

NASA Astrophysics Data System (ADS)

Djouadi, Abdelhak

2012-06-01

The Higgs mechanism plays a key role in the physics of elementary particles: in the context of the Standard Model, the theory which describes in a unified framework the electromagnetic, weak and strong nuclear interactions, it allows for the generation of particle masses while preserving the fundamental symmetries of the theory. This mechanism predicts the existence of a new type of particle, the scalar Higgs boson, with unique characteristics. The detection of this particle and the study of its fundamental properties is a major goal of high-energy particle colliders, such as the CERN Large Hadron Collider or LHC.

The Higgs Mechanism and the Orogin of Mass

NASA Astrophysics Data System (ADS)

Djouadi, Abdelhak

The Higgs mechanism plays a key role in the physics of elementary particles: in the context of the Standard Model, the theory which, describes in a unified framework the electromagnetic, weak, and strong nuclear interactions, it allows for the generation of particle masses while preserving the fundamental symmetries of the theory. This mechanism predicts the existence of a new type of particle, the scalar Higgs boson, with unique characteristics. The detection of this particle and the study of its fundamental properties is a major goal of high-energy particle colliders, such as the CERN Large Hadron Collider or LHC.

Race for the Higgs hots up as Tevatron seeks extension

NASA Astrophysics Data System (ADS)

Banks, Michael

2009-12-01

With researchers at CERN's Large Hadron Collider (LHC) having circulated protons for the first time since last year's accident, the US Department of Energy (DOE) is requesting 25m so that the Tevatron collider at the Fermi National Accelerator Laboratory in Illinois can run for an extra year until 2011. If the additional funding is granted, it would give physicists in the US an extra 12 months to close in on discovering the elusive Higgs boson. The DOE's request will now be reviewed before being part of President Barack Obama's 2011 budget request, which will be sent to Congress in February.

A discovery! The Higgs? Why is this important? How it was done.

ScienceCinema

Dawson, Sally; Gordan, Howard

2017-12-09

Data collected during 2011 and 2012 at the Large Hadron Collider (LHC) at CERN in Switzerland, the world's highest-energy proton collider, has culminated in the discovery of a new particle that is about 135 times heavier than a proton. But is it really the Higgs particle predicted by the theory that explains the origin of the mass of most elementary particles in the universe? The discovery and its possible identity is discussed by two Brookhaven Lab physicists, Sally Dawson and Howard Gordon, with deep roots in the hunt for the Higgs.

Protection of the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Schmidt, R.; Assmann, R.; Carlier, E.; Dehning, B.; Denz, R.; Goddard, B.; Holzer, E. B.; Kain, V.; Puccio, B.; Todd, B.; Uythoven, J.; Wenninger, J.; Zerlauth, M.

2006-11-01

The Large Hadron Collider (LHC) at CERN will collide two counter-rotating proton beams, each with an energy of 7 TeV. The energy stored in the superconducting magnet system will exceed 10 GJ, and each beam has a stored energy of 362 MJ which could cause major damage to accelerator equipment in the case of uncontrolled beam loss. Safe operation of the LHC will therefore rely on a complex system for equipment protection. The systems for protection of the superconducting magnets in case of quench must be fully operational before powering the magnets. For safe injection of the 450 GeV beam into the LHC, beam absorbers must be in their correct positions and specific procedures must be applied. Requirements for safe operation throughout the cycle necessitate early detection of failures within the equipment, and active monitoring of the beam with fast and reliable beam instrumentation, mainly beam loss monitors (BLM). When operating with circulating beams, the time constant for beam loss after a failure extends from apms to a few minutes—failures must be detected sufficiently early and transmitted to the beam interlock system that triggers a beam dump. It is essential that the beams are properly extracted on to the dump blocks at the end of a fill and in case of emergency, since the beam dump blocks are the only elements of the LHC that can withstand the impact of the full beam.

Air liquide 1.8 K refrigeration units for CERN LHC project

NASA Astrophysics Data System (ADS)

Hilbert, Benoît; Gistau-Baguer, Guy M.; Caillaud, Aurélie

2002-05-01

The Large Hadron Collider (LHC) will be CERN's next research instrument for high energy physics. This 27 km long circular accelerator will make intensive use of superconducting magnets, operated below 2.0 K. It will thus require high capacity refrigeration below 2.0 K [1, 2]. Coupled to a refrigerator providing 18 kW equivalent at 4.5 K [3], these systems will be able to absorb a cryogenic power of 2.4 kW at 1.8 K in nominal conditions. Air Liquide has designed one Cold Compressor System (CCS) pre-series for CERN-preceding 3 more of them (among 8 in total located around the machine). These systems, making use of cryogenic centrifugal compressors in a series arrangement coupled to room temperature screw compressors, are presented. Key components characteristics will be given.

On a Possibility of the Gravitational Wave Detection at the High Energy Colliders

NASA Astrophysics Data System (ADS)

Verma, Murli Manohar

A strong follow up of a previous proposal (ICHEP, Valencia 2014) is made leading to the first experiment to observe the gravitational waves at the collision sites at the colliders such as the Large Hadron Collider at CERN. The amplitudes have been calculated with regard to the sensitivity of the detector. Compared with the standard model physics, it is shown to have a measurable impact on the particle motions and corresponds to ‘missing’ energy in form of the gravitational wave loss. This is unlike the cosmological detectors like BICEP2 etc. where the indirect B mode polarization on CMBR were masked by dust. In contrast, this experiment would be the first experiment where the energy-momentum tensor of the source can be controlled.

Lattice QCD at finite temperature and density from Taylor expansion

NASA Astrophysics Data System (ADS)

Steinbrecher, Patrick

2017-01-01

In the first part, I present an overview of recent Lattice QCD simulations at finite temperature and density. In particular, we discuss fluctuations of conserved charges: baryon number, electric charge and strangeness. These can be obtained from Taylor expanding the QCD pressure as a function of corresponding chemical potentials. Our simulations were performed using quark masses corresponding to physical pion mass of about 140 MeV and allow a direct comparison to experimental data from ultra-relativistic heavy ion beams at hadron colliders such as the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN. In the second part, we discuss computational challenges for current and future exascale Lattice simulations with a focus on new silicon developments from Intel and NVIDIA.

Development and testing of a double length pets for the CLIC experimental area

NASA Astrophysics Data System (ADS)

Sánchez, L.; Carrillo, D.; Gavela, D.; Lara, A.; Rodríguez, E.; Gutiérrez, J. L.; Calero, J.; Toral, F.; Samoshkin, A.; Gudkov, D.; Riddone, G.

2014-05-01

CLIC (compact linear collider) is a future e+e- collider based on normal-conducting technology, currently under study at CERN. Its design is based on a novel two-beam acceleration scheme. The main beam gets RF power extracted from a drive beam through power extraction and transfer structures (PETS). The technical feasibility of CLIC is currently being proved by its Third Test Facility (CTF3) which includes the CLIC experimental area (CLEX). Two Double Length CLIC PETS will be installed in CLEX to validate their performance with beam. This paper is focused on the engineering design, fabrication and validation of this PETS first prototype. The design consists of eight identical bars, separated by radial slots in which damping material is located to absorb transverse wakefields, and two compact couplers placed at both ends of the bars to extract the generated power. The PETS bars are housed inside a vacuum tank designed to make the PETS as compact as possible. Several joint techniques such as vacuum brazing, electron beam and arc welding were used to complete the assembly. Finally, several tests such as dimensional control and leak testing were carried out to validate design and fabrication methods. In addition, RF measurements at low power were made to study frequency tuning.

An EUDET/AIDA Pixel Beam Telescope for Detector Development

NASA Astrophysics Data System (ADS)

Rubinskiy, I.; EUDET Consortium; AIDA Consortium

Ahigh resolution(σ< 2 μm) beam telescope based on monolithic active pixel sensors (MAPS) was developed within the EUDET collaboration. EUDET was a coordinated detector R&D programme for the future International Linear Collider providing test beam infrastructure to detector R&D groups. The telescope consists of six sensor planes with a pixel pitch of either 18.4 μm or 10 μmand canbe operated insidea solenoidal magnetic fieldofupto1.2T.Ageneral purpose cooling, positioning, data acquisition (DAQ) and offine data analysis tools are available for the users. The excellent resolution, readout rate andDAQintegration capabilities made the telescopea primary beam tests tool also for several CERN based experiments. In this report the performance of the final telescope is presented. The plans for an even more flexible telescope with three differentpixel technologies(ATLASPixel, Mimosa,Timepix) withinthenew European detector infrastructure project AIDA are presented.

LCFIPlus: A framework for jet analysis in linear collider studies

NASA Astrophysics Data System (ADS)

Suehara, Taikan; Tanabe, Tomohiko

2016-02-01

We report on the progress in flavor identification tools developed for a future e+e- linear collider such as the International Linear Collider (ILC) and Compact Linear Collider (CLIC). Building on the work carried out by the LCFIVertex collaboration, we employ new strategies in vertex finding and jet finding, and introduce new discriminating variables for jet flavor identification. We present the performance of the new algorithms in the conditions simulated using a detector concept designed for the ILC. The algorithms have been successfully used in ILC physics simulation studies, such as those presented in the ILC Technical Design Report.

Linear Collider Physics Resource Book for Snowmass 2001 - Part 3: Studies of Exotic and Standard Model Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Abe, T.; et al.

This Resource Book reviews the physics opportunities of a next-generation e+e- linear collider and discusses options for the experimental program. Part 3 reviews the possible experiments on that can be done at a linear collider on strongly coupled electroweak symmetry breaking, exotic particles, and extra dimensions, and on the top quark, QCD, and two-photon physics. It also discusses the improved precision electroweak measurements that this collider will make available.

Lessons learned from the SLC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Phinney, N.

The SLAC Linear Collider (SLC) is the first example of an entirely new type of lepton collider. Many years of effort were required to develop the understanding and techniques needed to approach design luminosity. This paper discusses some of the key issues and problems encountered in producing a working linear collider. These include the polarized source, techniques for emittance preservation, extensive feedback systems, and refinements in beam optimization in the final focus. The SLC experience has been invaluable for testing concepts and developing designs for a future linear collider.

CERN and LHC - Their Place in Global Science

ScienceCinema

None

2018-01-09

The Large Hadron Collider (LHC) is the largest scientific instrument in the world. It brings into collision intense beams of protons and ions to explore the structure of matter and investigate the forces of nature at an unprecedented energy scale, thus serving a community of some 7,000 particle physicists from all over the world.

The CERN Large Hadron Collider as a tool to study high-energy density matter.

PubMed

Tahir, N A; Kain, V; Schmidt, R; Shutov, A; Lomonosov, I V; Gryaznov, V; Piriz, A R; Temporal, M; Hoffmann, D H H; Fortov, V E

2005-04-08

The Large Hadron Collider (LHC) at CERN will generate two extremely powerful 7 TeV proton beams. Each beam will consist of 2808 bunches with an intensity per bunch of 1.15x10(11) protons so that the total number of protons in one beam will be about 3x10(14) and the total energy will be 362 MJ. Each bunch will have a duration of 0.5 ns and two successive bunches will be separated by 25 ns, while the power distribution in the radial direction will be Gaussian with a standard deviation, sigma=0.2 mm. The total duration of the beam will be about 89 mus. Using a 2D hydrodynamic code, we have carried out numerical simulations of the thermodynamic and hydrodynamic response of a solid copper target that is irradiated with one of the LHC beams. These calculations show that only the first few hundred proton bunches will deposit a high specific energy of 400 kJ/g that will induce exotic states of high energy density in matter.

HST at CERN an Amazing Adventure

NASA Astrophysics Data System (ADS)

Restivo, Evelyn

2009-04-01

The High School Teacher Program (HST) at the European Organization for Nuclear Research, CERN, in Geneva, Switzerland was initiated in 1998 by a group of scientists, as a multicultural international program designed to introduce high school physics teachers to high-energy physics. The goal of the program is to provide experiences and materials that will help teachers lead their students to a better understanding of the physical world. Interacting with physics teachers from around the world leads to new approaches for dealing with educational issues that all teachers encounter. The program includes a variety of tours, a series of lectures and classroom activities about the physics expected from the Large Hadron Collider.

Vanilla technicolor at linear colliders

NASA Astrophysics Data System (ADS)

Frandsen, Mads T.; Järvinen, Matti; Sannino, Francesco

2011-08-01

We analyze the reach of linear colliders for models of dynamical electroweak symmetry breaking. We show that linear colliders can efficiently test the compositeness scale, identified with the mass of the new spin-one resonances, until the maximum energy in the center of mass of the colliding leptons. In particular we analyze the Drell-Yan processes involving spin-one intermediate heavy bosons decaying either leptonically or into two standard model gauge bosons. We also analyze the light Higgs production in association with a standard model gauge boson stemming also from an intermediate spin-one heavy vector.

The management of large cabling campaigns during the Long Shutdown 1 of LHC

NASA Astrophysics Data System (ADS)

Meroli, S.; Machado, S.; Formenti, F.; Frans, M.; Guillaume, J. C.; Ricci, D.

2014-03-01

The Large Hadron Collider at CERN entered into its first 18 month-long shutdown period in February 2013. During this period the entire CERN accelerator complex will undergo major consolidation and upgrade works, preparing the machines for LHC operation at nominal energy (7 TeV/beam). One of the most challenging activities concerns the cabling infrastructure (copper and optical fibre cables) serving the CERN data acquisition, networking and control systems. About 1000 kilometres of cables, distributed in different machine areas, will be installed, representing an investment of about 15 MCHF. This implies an extraordinary challenge in terms of project management, including resource and activity planning, work execution and quality control. The preparation phase of this project started well before its implementation, by defining technical solutions and setting financial plans for staff recruitment and material supply. Enhanced task coordination was further implemented by deploying selected competences to form a central support team.

Numerical simulations of energy deposition caused by 50 MeV—50 TeV proton beams in copper and graphite targets

NASA Astrophysics Data System (ADS)

Nie, Y.; Schmidt, R.; Chetvertkova, V.; Rosell-Tarragó, G.; Burkart, F.; Wollmann, D.

2017-08-01

The conceptual design of the Future Circular Collider (FCC) is being carried out actively in an international collaboration hosted by CERN, for the post-Large Hadron Collider (LHC) era. The target center-of-mass energy of proton-proton collisions for the FCC is 100 TeV, nearly an order of magnitude higher than for LHC. The existing CERN accelerators will be used to prepare the beams for FCC. Concerning beam-related machine protection of the whole accelerator chain, it is critical to assess the consequences of beam impact on various accelerator components in the cases of controlled and uncontrolled beam losses. In this paper, we study the energy deposition of protons in solid copper and graphite targets, since the two materials are widely used in magnets, beam screens, collimators, and beam absorbers. Nominal injection and extraction energies in the hadron accelerator complex at CERN were selected in the range of 50 MeV-50 TeV. Three beam sizes were studied for each energy, corresponding to typical values of the betatron function. Specifically for thin targets, comparisons between fluka simulations and analytical Bethe equation calculations were carried out, which showed that the damage potential of a few-millimeter-thick graphite target and submillimeter-thick copper foil can be well estimated directly by the Bethe equation. The paper provides a valuable reference for the quick evaluation of potential damage to accelerator elements over a large range of beam parameters when beam loss occurs.

Physics Goals and Experimental Challenges of the Proton-Proton High-Luminosity Operation of the LHC

NASA Astrophysics Data System (ADS)

Campana, P.; Klute, M.; Wells, P. S.

2016-10-01

The completion of Run 1 of the Large Hadron Collider (LHC) at CERN has seen the discovery of the Higgs boson and an unprecedented number of precise measurements of the Standard Model, and Run 2 has begun to provide the first data at higher energy. The high-luminosity upgrade of the LHC (HL-LHC) and the four experiments (ATLAS, CMS, ALICE, and LHCb) will exploit the full potential of the collider to discover and explore new physics beyond the Standard Model. We review the experimental challenges and the physics opportunities in proton-proton collisions at the HL-LHC.

The perilous world of the wardrobe

NASA Astrophysics Data System (ADS)

Gillies, James

2010-01-01

Last spring a man called Walter Wagner claimed that if you can conceive of two possible outcomes to an event, then the probability of each one happening is 50:50. His pronouncement came in an episode of The Daily Show, a US satirical news TV programme, but he was not trying to be funny. Wagner, a plaintiff in a 2008 court case in Hawaii that tried to prevent CERN from switching on the Large Hadron Collider (LHC), has long believed that experiments at the collider could cause the world to go up in a puff of smoke. And the probability of this happening, as conceived by Wagner, is one in two. Scary.

Hadron collider searches for diboson resonances

NASA Astrophysics Data System (ADS)

Dorigo, Tommaso

2018-05-01

This review covers results of searches for new elementary particles that decay into boson pairs (dibosons), performed at the CERN Large Hadron Collider in proton-proton collision data collected by the ATLAS and CMS experiments at 7-, 8-, and 13-TeV center-of-mass energy until the year 2017. The available experimental results of the analysis of final states including most of the possible two-object combinations of W and Z bosons, photons, Higgs bosons, and gluons place stringent constraints on a variety of theoretical ideas that extend the standard model, pushing into the multi-TeV region the scale of allowed new physics phenomena.

Unveiling the top secrets with the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Chierici, R.

2013-12-01

Top quark physics is one of the pillars of fundamental research in the field of high energy physics. It not only gives access to precision measurements for constraining the Standard Model of particles and interactions but also it represents a privileged domain for new physics searches. This contribution summarizes the main results in top quark physics obtained with the two general-purpose detectors ATLAS and CMS during the first two years of operations of the Large Hadron Collider (LHC) at CERN. It covers the 2010 and 2011 data taking periods, where the LHC ran at a centre-of-mass energy of 7 TeV.

High Energy Colliding Beams; What Is Their Future?

NASA Astrophysics Data System (ADS)

Richter, Burton

The success of the first few years of LHC operations at CERN, and the expectation of more to come as the LHC's performance improves, are already leading to discussions of what should be next for both proton-proton and electron-positron colliders. In this discussion I see too much theoretical desperation caused by the so-far-unsuccessful hunt for what is beyond the Standard Model, and too little of the necessary interaction of the accelerator, experimenter, and theory communities necessary for a scientific and engineering success. Here, I give my impressions of the problem, its possible solution, and what is needed to have both a scientifically productive and financially viable future.

High Energy Colliding Beams; What Is Their Future?

NASA Astrophysics Data System (ADS)

Richter, Burton

2014-04-01

The success of the first few years of LHC operations at CERN, and the expectation of more to come as the LHC's performance improves, are already leading to discussions of what should be next for both proton-proton and electron-positron colliders. In this discussion I see too much theoretical desperation caused by the so-far-unsuccessful hunt for what is beyond the Standard Model, and too little of the necessary interaction of the accelerator, experimenter, and theory communities necessary for a scientific and engineering success. Here, I give my impressions of the problem, its possible solution, and what is needed to have both a scientifically productive and financially viable future.

High Energy Colliding Beams; What Is Their Future?

NASA Astrophysics Data System (ADS)

Richter, Burton

2015-02-01

The success of the first few years of LHC operations at CERN, and the expectation of more to come as the LHC's performance improves, are already leading to discussions of what should be next for both proton-proton and electron-positron colliders. In this discussion I see too much theoretical desperation caused by the so-far-unsuccessful hunt for what is beyond the Standard Model, and too little of the necessary interaction of the accelerator, experimenter, and theory communities necessary for a scientific and engineering success. Here, I give my impressions of the problem, its possible solution, and what is needed to have both a scientifically productive and financially viable future.

Introducing the LHC in the Classroom: An Overview of Education Resources Available

ERIC Educational Resources Information Center

Wiener, Gerfried J.; Woithe, Julia; Brown, Alexander; Jende, Konrad

2016-01-01

In the context of the recent re-start of CERN's Large Hadron Collider (LHC) and the challenge presented by unidentified falling objects (UFOs), we seek to facilitate the introduction of high energy physics in the classroom. Therefore, this paper provides an overview of the LHC and its operation, highlighting existing education resources, and…

Exploring the Standard Model of Particles

ERIC Educational Resources Information Center

Johansson, K. E.; Watkins, P. M.

2013-01-01

With the recent discovery of a new particle at the CERN Large Hadron Collider (LHC) the Higgs boson could be about to be discovered. This paper provides a brief summary of the standard model of particle physics and the importance of the Higgs boson and field in that model for non-specialists. The role of Feynman diagrams in making predictions for…

Fermilab | Science at Fermilab | Experiments & Projects | Energy Frontier |

Science.gov Websites

Collider The LHC at CERN, the European Organization for Nuclear Research, is the largest, most complex and . Physicists take interest in collisions that stand out due to the force of their impact or for the types of identify the types of particles created by the collisions and to determine if they have discovered

HYPATIA--An Online Tool for ATLAS Event Visualization

ERIC Educational Resources Information Center

Kourkoumelis, C.; Vourakis, S.

2014-01-01

This paper describes an interactive tool for analysis of data from the ATLAS experiment taking place at the world's highest energy particle collider at CERN. The tool, called HYPATIA/applet, enables students of various levels to become acquainted with particle physics and look for discoveries in a similar way to that of real research.

Hangout with CERN: a direct conversation with the public

NASA Astrophysics Data System (ADS)

Rao, Achintya; Goldfarb, Steven; Kahle, Kate

2016-04-01

Hangout with CERN refers to a weekly, half-hour-long, topical webcast hosted at CERN. The aim of the programme is threefold: (i) to provide a virtual tour of various locations and facilities at CERN, (ii) to discuss the latest scientific results from the laboratory, and, most importantly, (iii) to engage in conversation with the public and answer their questions. For each ;episode;, scientists gather around webcam-enabled computers at CERN and partner institutes/universities, connecting to one another using the Google+ social network's ;Hangouts; tool. The show is structured as a conversation mediated by a host, usually a scientist, and viewers can ask questions to the experts in real time through a Twitter hashtag or YouTube comments. The history of Hangout with CERN can be traced back to ICHEP 2012, where several physicists crowded in front of a laptop connected to Google+, using a ;Hangout On Air; webcast to explain to the world the importance of the discovery of the Higgs-like boson, announced just two days before at the same conference. Hangout with CERN has also drawn inspiration from two existing outreach endeavours: (i) ATLAS Virtual Visits, which connected remote visitors with scientists in the ATLAS Control Room via video conference, and (ii) the Large Hangout Collider, in which CMS scientists gave underground tours via Hangouts to groups of schools and members of the public around the world. In this paper, we discuss the role of Hangout with CERN as a bi-directional outreach medium and an opportunity to train scientists in effective communication.

Cryogenic studies for the proposed CERN large hadron electron collider (LHEC)

NASA Astrophysics Data System (ADS)

Haug, F.; LHeC Study Team, The

2012-06-01

The LHeC (Large Hadron electron Collider) is a proposed future colliding beam facility for lepton-nucleon scattering particle physics at CERN. A new 60 GeV electron accelerator will be added to the existing 27 km circumference 7 TeV LHC for collisions of electrons with protons and heavy ions. Two basic design options are being pursued. The first is a circular accelerator housed in the existing LHC tunnel which is referred to as the "Ring-Ring" version. Low field normal conducting magnets guide the particle beam while superconducting (SC) RF cavities cooled to 2 K are installed at two opposite locations at the LHC tunnel to accelerate the beams. For this version in addition a 10 GeV re-circulating SC injector will be installed. In total four refrigerators with cooling capacities between 1.2 kW and 3 kW @ 4.5 K are needed. The second option, referred to as the "Linac-Ring" version consists of a race-track re-circulating energyrecovery type machine with two 1 km long straight acceleration sections. The 944 high field 2 K SC cavities dissipate 30 kW at CW operation. Eight 10 kW @ 4.5 K refrigerators are proposed. The particle detector contains a combined SC solenoid and dipole forming the cold mass and an independent liquid argon calorimeter. Cooling is done with two individual small sized cryoplants; a 4.5 K helium, and a 87 K liquid nitrogen plant.

Physics at the SPS.

PubMed

Gatignon, L

2018-05-01

The CERN Super Proton Synchrotron (SPS) has delivered a variety of beams to a vigorous fixed target physics program since 1978. In this paper, we restrict ourselves to the description of a few illustrative examples in the ongoing physics program at the SPS. We will outline the physics aims of the COmmon Muon Proton Apparatus for Structure and Spectroscopy (COMPASS), north area 64 (NA64), north area 62 (NA62), north area 61 (NA61), and advanced proton driven plasma wakefield acceleration experiment (AWAKE). COMPASS studies the structure of the proton and more specifically of its spin. NA64 searches for the dark photon A', which is the messenger for interactions between normal and dark matter. The NA62 experiment aims at a 10% precision measurement of the very rare decay K + → π + νν. As this decay mode can be calculated very precisely in the Standard Model, it offers a very good opportunity to look for new physics beyond the Standard Model. The NA61/SHINE experiment studies the phase transition to Quark Gluon Plasma, a state in which the quarks and gluons that form the proton and the neutron are de-confined. Finally, AWAKE investigates proton-driven wake field acceleration: a promising technique to accelerate electrons with very high accelerating gradients. The Physics Beyond Colliders study at CERN is paving the way for a significant and diversified continuation of this already rich and compelling physics program that is complementary to the one at the big colliders like the Large Hadron Collider.

Physics at the SPS

NASA Astrophysics Data System (ADS)

Gatignon, L.

2018-05-01

The CERN Super Proton Synchrotron (SPS) has delivered a variety of beams to a vigorous fixed target physics program since 1978. In this paper, we restrict ourselves to the description of a few illustrative examples in the ongoing physics program at the SPS. We will outline the physics aims of the COmmon Muon Proton Apparatus for Structure and Spectroscopy (COMPASS), north area 64 (NA64), north area 62 (NA62), north area 61 (NA61), and advanced proton driven plasma wakefield acceleration experiment (AWAKE). COMPASS studies the structure of the proton and more specifically of its spin. NA64 searches for the dark photon A', which is the messenger for interactions between normal and dark matter. The NA62 experiment aims at a 10% precision measurement of the very rare decay K+ → π+νν. As this decay mode can be calculated very precisely in the Standard Model, it offers a very good opportunity to look for new physics beyond the Standard Model. The NA61/SHINE experiment studies the phase transition to Quark Gluon Plasma, a state in which the quarks and gluons that form the proton and the neutron are de-confined. Finally, AWAKE investigates proton-driven wake field acceleration: a promising technique to accelerate electrons with very high accelerating gradients. The Physics Beyond Colliders study at CERN is paving the way for a significant and diversified continuation of this already rich and compelling physics program that is complementary to the one at the big colliders like the Large Hadron Collider.

PanDA for COMPASS at JINR

NASA Astrophysics Data System (ADS)

Petrosyan, A. Sh.

2016-09-01

PanDA (Production and Distributed Analysis System) is a workload management system, widely used for data processing at experiments on Large Hadron Collider and others. COMPASS is a high-energy physics experiment at the Super Proton Synchrotron. Data processing for COMPASS runs locally at CERN, on lxbatch, the data itself stored in CASTOR. In 2014 an idea to start running COMPASS production through PanDA arose. Such transformation in experiment's data processing will allow COMPASS community to use not only CERN resources, but also Grid resources worldwide. During the spring and summer of 2015 installation, validation and migration work is being performed at JINR. Details and results of this process are presented in this paper.

Ian Hinchliffe Answers Your Higgs Boson Questions

ScienceCinema

Hinchliffe, Ian

2017-12-09

contingent with the ATLAS experiment at CERN, answers many of your questions about the Higgs boson. Ian invited viewers to send in questions about the Higgs via email, Twitter, Facebook, or YouTube in an "Ask a Scientist" video posted July 3: http://youtu.be/xhuA3wCg06s CERN's July 4 announcement that the ATLAS and CMS experiments at the Large Hadron Collider have discovered a particle "consistent with the Higgs boson" has raised questions about what scientists have found and what still remains to be found -- and what it all means. If you have suggestions for future "Ask a Scientist" videos, post them below or send ideas to askascientist@lbl.gov

Development of radiation tolerant components for the Quench Protection System at CERN

NASA Astrophysics Data System (ADS)

Bitterling, O.; Denz, R.; Steckert, J.; Uznanski, S.

2016-01-01

This paper describes the results of irradiation campaigns with the high resolution Analog to Digital Converter (ADC) ADS1281. This ADC will be used as part of a revised quench detection circuit for the 600 A corrector magnets at the CERN Large Hadron Collider (LHC) . To verify the radiation tolerance of the ADC an irradiation campaign using a proton beam, applying doses up to 3,4 kGy was conducted. The resulting data and an analysis of the found failure modes is discussed in this paper. Several mitigation measures are described that allow to reduce the error rate to levels acceptable for operation as part of the LHC QPS.

The accuracy of the ATLAS muon X-ray tomograph

NASA Astrophysics Data System (ADS)

Avramidou, R.; Berbiers, J.; Boudineau, C.; Dechelette, C.; Drakoulakos, D.; Fabjan, C.; Grau, S.; Gschwendtner, E.; Maugain, J.-M.; Rieder, H.; Rangod, S.; Rohrbach, F.; Sbrissa, E.; Sedykh, E.; Sedykh, I.; Smirnov, Y.; Vertogradov, L.; Vichou, I.

2003-01-01

A gigantic detector, the ATLAS project, is under construction at CERN for particle physics research at the Large Hadron Collider which is to be ready by 2006. An X-ray tomograph has been developed, designed and constructed at CERN in order to control the mechanical quality of the ATLAS muon chambers. We reached a measurement accuracy of 2 μm systematic and 2 μm statistical uncertainties in the horizontal and vertical directions in the working area 220 cm (horizontal)×60 cm (vertical). Here we describe in detail the fundamental approach of the basic principle chosen to achieve such good accuracy. In order to crosscheck our precision, key results of measurements are presented.

Possible limits of plasma linear colliders

NASA Astrophysics Data System (ADS)

Zimmermann, F.

2017-07-01

Plasma linear colliders have been proposed as next or next-next generation energy-frontier machines for high-energy physics. I investigate possible fundamental limits on energy and luminosity of such type of colliders, considering acceleration, multiple scattering off plasma ions, intrabeam scattering, bremsstrahlung, and betatron radiation. The question of energy efficiency is also addressed.

Status of the Future Circular Collider Study

NASA Astrophysics Data System (ADS)

Benedikt, Michael

2016-03-01

Following the 2013 update of the European Strategy for Particle Physics, the international Future Circular Collider (FCC) Study has been launched by CERN as host institute, to design an energy frontier hadron collider (FCC-hh) in a new 80-100 km tunnel with a centre-of-mass energy of about 100 TeV, an order of magnitude beyond the LHC's, as a long-term goal. The FCC study also includes the design of a 90-350 GeV high-luminosity lepton collider (FCC-ee) installed in the same tunnel, serving as Higgs, top and Z factory, as a potential intermediate step, as well as an electron-proton collider option (FCC-he). The physics cases for such machines will be assessed and concepts for experiments will be developed in time for the next update of the European Strategy for Particle Physics by the end of 2018. The presentation will summarize the status of machine designs and parameters and discuss the essential technical components to be developed in the frame of the FCC study. Key elements are superconducting accelerator-dipole magnets with a field of 16 T for the hadron collider and high-power, high-efficiency RF systems for the lepton collider. In addition the unprecedented beam power presents special challenges for the hadron collider for all aspects of beam handling and machine protection. First conclusions of geological investigations and implementation studies will be presented. The status of the FCC collaboration and the further planning for the study will be outlined.

Preliminary design of the beam screen cooling for the Future Circular Collider of hadron beams

NASA Astrophysics Data System (ADS)

Kotnig, C.; Tavian, L.

2015-12-01

Following recommendations of the recent update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. This study considers an option for a very high energy (100 TeV) hadron-hadron collider located in a quasi-circular underground tunnel having a circumference of 80 to 100 km. The synchrotron radiation emitted by the high-energy hadron beam increases by more than two orders of magnitude compared to the LHC. To reduce the entropic load on the superconducting magnets’ refrigeration system, beam screens are indispensable to extract the heat load at a higher temperature level. After illustrating the decisive constraints of the beam screen's refrigeration design, this paper presents a preliminary design of the length of a continuous cooling loop comparing helium and neon, for different cooling channel geometries with emphasis on the cooling length limitations and the exergetic efficiency.

Effects of initial-state nucleon shadowing on the elliptic flow of thermal photons

NASA Astrophysics Data System (ADS)

Dasgupta, Pingal; Chatterjee, Rupa; Singh, Sushant K.; Alam, Jan-e.

2018-03-01

Recently the effect of nucleon shadowing on the Monte Carlo-Glauber initial condition was studied and its role on the centrality dependence of elliptic flow (v2) and fluctuations in initial eccentricity for different colliding nuclei were explored. It was found that the results with shadowing effects are closer to the QCD-based dynamical model as well as to the experimental data. Inspired by this outcome, in this work we study the transverse momentum (pT) spectra and elliptic flow of thermal photons for Au +Au collisions at the BNL Relativisitic Heavy Ion Collider and Pb +Pb collisions at the CERN Large Hadron Collider by incorporating the shadowing effects in deducing the initial energy density profile required to solve the relativistic hydrodynamical equations. We find that the thermal photon spectra remain almost unaltered; however, the elliptic flow of photons is found to be enhanced significantly due to shadowing effects.

Gauge coupling unification and light exotica in string theory.

PubMed

Raby, Stuart; Wingerter, Akin

2007-08-03

In this Letter we consider the consequences for the CERN Large Hadron Collider of light vectorlike exotica with fractional electric charge. It is shown that such states are found in orbifold constructions of the heterotic string. Moreover, these exotica are consistent with gauge coupling unification at one loop, even though they do not come in complete multiplets of SU(5).

Intercontinental Multi-Domain Monitoring for LHC with perfSONAR

NASA Astrophysics Data System (ADS)

Vicinanza, D.

2012-12-01

The Large Hadron Collider (LHC) is currently running at CERN in Geneva, Switzerland. Physicists are using LHC to recreate the conditions just after the Big Bang, by colliding two beams of particles and heavy ions head-on at very high energy. The project is generating more than 15 TB of raw data per year, plus 10 TB of “event summary data”. This data is sent out from CERN to eleven Tier 1 research centres in Europe, Asia, and North America using a multi-gigabits Optical Private Network (OPN), the LHCOPN. Tier 1 sites are then connected to 100+ academic and research institutions in the world (the Tier 2s) through a Multipoint to Multipoint network, the LHC Open Network Environment (LHCONE). Network monitoring on such complex network architecture to ensure robust and reliable operation is of crucial importance. The chosen approach for monitoring the OPN and ONE is based on the perfSONAR framework, which is designed for multi-domain monitoring environments. perfSONAR (www.perfsonar.net) is an infrastructure for performance monitoring data exchange between networks, making it easier to solve performance problems occurring between network measurement points interconnected through several network domains.

Top-quark pairs at high invariant mass: a model-independent discriminator of new physics at the Large Hadron Collider.

PubMed

Barger, Vernon; Han, Tao; Walker, Devin G E

2008-01-25

We study top-quark pair production to probe new physics at the CERN Large Hadron Collider. We propose reconstruction methods for tt[over] semileptonic events and use them to reconstruct the tt[over] invariant mass. The angular distribution of top quarks in their c.m. frame can determine the spin and production subprocess for each new physics resonance. Forward-backward asymmetry and CP-odd variables can be constructed to further delineate the nature of new physics. We parametrize the new resonances with a few generic parameters and show high invariant mass top pair production may provide an early indicator for new physics beyond the standard model.

Experimental results on chiral magnetic and vortical effects

DOE PAGES

Wang, Gang; Wen, Liwen

2017-01-12

Various novel transport phenomena in chiral systems result from the interplay of quantum anomalies with magnetic field and vorticity in high-energy heavy-ion collisions and could survive the expansion of the fireball and be detected in experiments. Among them are the chiral magnetic effect, the chiral vortical effect, and the chiral magnetic wave, the experimental searches for which have aroused extensive interest. As a result, the goal of this review is to describe the current status of experimental studies at Relativistic Heavy-Ion Collider at BNL and the Large Hadron Collider at CERN and to outline the future work in experiment neededmore » to eliminate the existing uncertainties in the interpretation of the data.« less

Big Science and the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Giudice, Gian Francesco

2012-03-01

The Large Hadron Collider (LHC), the particle accelerator operating at CERN, is probably the most complex and ambitious scientific project ever accomplished by humanity. The sheer size of the enterprise, in terms of financial and human resources, naturally raises the question whether society should support such costly basic-research programs. I address this question by first reviewing the process that led to the emergence of Big Science and the role of large projects in the development of science and technology. I then compare the methodologies of Small and Big Science, emphasizing their mutual linkage. Finally, after examining the cost of Big Science projects, I highlight several general aspects of their beneficial implications for society.

Particle multiplicities in lead-lead collisions at the CERN large hadron collider from nonlinear evolution with running coupling corrections.

PubMed

Albacete, Javier L

2007-12-31

We present predictions for the pseudorapidity density of charged particles produced in central Pb-Pb collisions at the LHC. Particle production in such collisions is calculated in the framework of k(t) factorization. The nuclear unintegrated gluon distributions at LHC energies are determined from numerical solutions of the Balitsky-Kovchegov equation including recently calculated running coupling corrections. The initial conditions for the evolution are fixed by fitting Relativistic Heavy Ion Collider data at collision energies square root[sNN]=130 and 200 GeV per nucleon. We obtain dNch(Pb-Pb)/deta(square root[sNN]=5.5 TeV)/eta=0 approximately 1290-1480.

Towards future circular colliders

NASA Astrophysics Data System (ADS)

Benedikt, Michael; Zimmermann, Frank

2016-09-01

The Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN) presently provides proton-proton collisions at a center-of-mass (c.m.) energy of 13 TeV. The LHC design was started more than 30 years ago, and its physics program will extend through the second half of the 2030's. The global Future Circular Collider (FCC) study is now preparing for a post-LHC project. The FCC study focuses on the design of a 100-TeV hadron collider (FCC-hh) in a new ˜100 km tunnel. It also includes the design of a high-luminosity electron-positron collider (FCCee) as a potential intermediate step, and a lepton-hadron collider option (FCC-he). The scope of the FCC study comprises accelerators, technology, infrastructure, detectors, physics, concepts for worldwide data services, international governance models, and implementation scenarios. Among the FCC core technologies figure 16-T dipole magnets, based on Nb3 S n superconductor, for the FCC-hh hadron collider, and a highly-efficient superconducting radiofrequency system for the FCC-ee lepton collider. Following the FCC concept, the Institute of High Energy Physics (IHEP) in Beijing has initiated a parallel design study for an e + e - Higgs factory in China (CEPC), which is to be succeeded by a high-energy hadron collider (SPPC). At present a tunnel circumference of 54 km and a hadron collider c.m. energy of about 70 TeV are being considered. After a brief look at the LHC, this article reports the motivation and the present status of the FCC study, some of the primary design challenges and R&D subjects, as well as the emerging global collaboration.

Of Linear Colliders, the GDE Workshop at Bangalore, Mughals, Camels, Elephants and Sundials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loew, Greg

In this colloquium, the speaker will give a summary of the recent International Linear Collider (ILC) Global Design Effort (GDE) Workshop at Bangalore and how the High Energy Physics community converged to this meeting after many years of electron-positron linear collider design and experimental work. Given that this workshop for the first time took place in India, the speaker will also show a few pictures and talk briefly about what he learned in that fascinating country.

Capacitively coupled hybrid pixel assemblies for the CLIC vertex detector

NASA Astrophysics Data System (ADS)

Tehrani, N. Alipour; Arfaoui, S.; Benoit, M.; Dannheim, D.; Dette, K.; Hynds, D.; Kulis, S.; Perić, I.; Petrič, M.; Redford, S.; Sicking, E.; Valerio, P.

2016-07-01

The vertex detector at the proposed CLIC multi-TeV linear e+e- collider must have minimal material content and high spatial resolution, combined with accurate time-stamping to cope with the expected high rate of beam-induced backgrounds. One of the options being considered is the use of active sensors implemented in a commercial high-voltage CMOS process, capacitively coupled to hybrid pixel ASICs. A prototype of such an assembly, using two custom designed chips (CCPDv3 as active sensor glued to a CLICpix readout chip), has been characterised both in the lab and in beam tests at the CERN SPS using 120 GeV/c positively charged hadrons. Results of these characterisation studies are presented both for single and dual amplification stages in the active sensor, where efficiencies of greater than 99% have been achieved at -60 V substrate bias, with a single hit resolution of 6.1 μm . Pixel cross-coupling results are also presented, showing the sensitivity to placement precision and planarity of the glue layer.

Laser-plasma-based linear collider using hollow plasma channels

DOE PAGES

Schroeder, C. B.; Benedetti, C.; Esarey, E.; ...

2016-03-03

A linear electron–positron collider based on laser-plasma accelerators using hollow plasma channels is considered. Laser propagation and energy depletion in the hollow channel is discussed, as well as the overall efficiency of the laser-plasma accelerator. Example parameters are presented for a 1-TeV and 3-TeV center-of-mass collider based on laser-plasma accelerators.

Ian Hinchliffe Answers Your Higgs Boson Questions

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinchliffe, Ian

contingent with the ATLAS experiment at CERN, answers many of your questions about the Higgs boson. Ian invited viewers to send in questions about the Higgs via email, Twitter, Facebook, or YouTube in an "Ask a Scientist" video posted July 3: http://youtu.be/xhuA3wCg06s CERN's July 4 announcement that the ATLAS and CMS experiments at the Large Hadron Collider have discovered a particle "consistent with the Higgs boson" has raised questions about what scientists have found and what still remains to be found -- and what it all means. If you have suggestions for future "Ask a Scientist" videos, post them belowmore » or send ideas to askascientist@lbl.gov« less

How can we turn a science exhibition on a really success outreach activity?

NASA Astrophysics Data System (ADS)

Farrona, A. M. M.; Vilar, R.

2016-04-01

In April 2013, a CERN exhibition was shown in Santander: ;The largest scientific instrument ever built;. Around the exhibition, were proposed several activities: guide tours for children, younger and adults, workshops, film projections… In this way, the exhibition was visited by more than two thousand persons. We must keep in mind that Santander is a small city and it population does not usually take part in outreach activity. With this contribution, we want to teach the way in which it is possible to take advantage of science exhibitions. It made possible to show the Large Hadron Collider at CERN experiment to the great majority of Santander population, and to awaken their interest in or enthusiasm for science.

Proton enhancement at large pT at the CERN large hadron collider without structure in associated-particle distribution.

PubMed

Hwa, Rudolph C; Yang, C B

2006-07-28

The production of pions and protons in the pT range between 10 and 20 GeV/c for Pb+Pb collisions at CERN LHC is studied in the recombination model. It is shown that the dominant mechanism for hadronization is the recombination of shower partons from neighboring jets when the jet density is high. Protons are more copiously produced than pions in that pT range because the coalescing partons can have lower momentum fractions, but no thermal partons are involved. The proton-to-pion ratio can be as high as 20. When such high pT hadrons are used as trigger particles, there will not be any associated particles that are not in the background.

New results on diamond pixel sensors using ATLAS frontend electronics

NASA Astrophysics Data System (ADS)

Keil, M.; Adam, W.; Berdermann, E.; Bergonzo, P.; de Boer, W.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Dulinski, W.; Doroshenko, J.; Doucet, M.; van Eijk, B.; Fallou, A.; Fischer, P.; Fizzotti, F.; Kania, D.; Gan, K. K.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Kass, R.; Knöpfle, K. T.; Koeth, T.; Krammer, M.; Logiudice, A.; mac Lynne, L.; Manfredotti, C.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pan, L. S.; Pernicka, M.; Perera, L.; Riester, J. L.; Roe, S.; Rudge, A.; Russ, J.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Suter, B.; Trischuk, W.; Tromson, D.; Vittone, E.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

2003-03-01

Diamond is a promising sensor material for future collider experiments due to its radiation hardness. Diamond pixel sensors have been bump bonded to an ATLAS pixel readout chip using PbSn solder bumps. Single chip devices have been characterised by lab measurements and in a high-energy pion beam at CERN. Results on charge collection, spatial resolution, efficiency and the charge carrier lifetime are presented.

High Energy Colliders

NASA Astrophysics Data System (ADS)

Palmer, R. B.; Gallardo, J. C.

INTRODUCTION PHYSICS CONSIDERATIONS GENERAL REQUIRED LUMINOSITY FOR LEPTON COLLIDERS THE EFFECTIVE PHYSICS ENERGIES OF HADRON COLLIDERS HADRON-HADRON MACHINES LUMINOSITY SIZE AND COST CIRCULAR e^{+}e^- MACHINES LUMINOSITY SIZE AND COST e^{+}e^- LINEAR COLLIDERS LUMINOSITY CONVENTIONAL RF SUPERCONDUCTING RF AT HIGHER ENERGIES γ - γ COLLIDERS μ ^{+} μ^- COLLIDERS ADVANTAGES AND DISADVANTAGES DESIGN STUDIES STATUS AND REQUIRED R AND D COMPARISION OF MACHINES CONCLUSIONS DISCUSSION

Reinventing the Accelerator for the High Energy Frontier

ScienceCinema

Rosenzweig, James [UCLA, Los Angeles, California, United States

2017-12-09

The history of discovery in high-energy physics has been intimately connected with progress in methods of accelerating particles for the past 75 years. This remains true today, as the post-LHC era in particle physics will require significant innovation and investment in a superconducting linear collider. The choice of the linear collider as the next-generation discovery machine, and the selection of superconducting technology has rather suddenly thrown promising competing techniques -- such as very large hadron colliders, muon colliders, and high-field, high frequency linear colliders -- into the background. We discuss the state of such conventional options, and the likelihood of their eventual success. We then follow with a much longer view: a survey of a new, burgeoning frontier in high energy accelerators, where intense lasers, charged particle beams, and plasmas are all combined in a cross-disciplinary effort to reinvent the accelerator from its fundamental principles on up.

Alternate approaches to future electron-positron linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loew, G.A.

1998-07-01

The purpose of this article is two-fold: to review the current international status of various design approaches to the next generation of e{sup +}e{sup {minus}} linear colliders, and on the occasion of his 80th birthday, to celebrate Richard B. Neal`s many contributions to the field of linear accelerators. As it turns out, combining these two tasks is a rather natural enterprise because of Neal`s long professional involvement and insight into many of the problems and options which the international e{sup +}e{sup {minus}} linear collider community is currently studying to achieve a practical design for a future machine.

2009 Linear Collider Workshop of the Americas

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seidel, Sally

The 2009 Linear Collider Workshop of the Americas was held on the campus of the University of New Mexico from 29 September to 3 October, 2009. This was a joint meeting of the American Linear Collider Physics Group and the ILC Global Design Effort. Two hundred fifty people attended. The number of scientific contributions was 333. The complete agenda, with links to all of the presentations, is available at physics.unm.edu/LCWA09/. The meeting brought together international experts as well as junior scientists, to discuss the physics potential of the linear collider and advances in detector technology. The validation of detector designsmore » was announced, and the detector design groups planned the next phase of the effort. Detector R&D teams reported on progress on many topics including calorimetry and tracking. Recent accelerator design considerations were discussed in a special session for experimentalists and theorists.« less

Fermilab Today

Science.gov Websites

Fundamental Physics in the Non-Linear Regime 3:30 p.m. Director's Coffee Break - 2nd Flr X-Over 4:00 p.m. All Week archive Fermilab Safety Tip of the Week archive Linear Collider News archive Fermilab Today Committee ECFA Study of Physics and Detectors for a Linear Collider" and GDE member, explained the

Exergy Analysis of the Cryogenic Helium Distribution System for the Large Hadron Collider (lhc)

NASA Astrophysics Data System (ADS)

Claudet, S.; Lebrun, Ph.; Tavian, L.; Wagner, U.

2010-04-01

The Large Hadron Collider (LHC) at CERN features the world's largest helium cryogenic system, spreading over the 26.7 km circumference of the superconducting accelerator. With a total equivalent capacity of 145 kW at 4.5 K including 18 kW at 1.8 K, the LHC refrigerators produce an unprecedented exergetic load, which must be distributed efficiently to the magnets in the tunnel over the 3.3 km length of each of the eight independent sectors of the machine. We recall the main features of the LHC cryogenic helium distribution system at different temperature levels and present its exergy analysis, thus enabling to qualify second-principle efficiency and identify main remaining sources of irreversibility.

Using Supercomputers to Probe the Early Universe

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giorgi, Elena Edi

For decades physicists have been trying to decipher the first moments after the Big Bang. Using very large telescopes, for example, scientists scan the skies and look at how fast galaxies move. Satellites study the relic radiation left from the Big Bang, called the cosmic microwave background radiation. And finally, particle colliders, like the Large Hadron Collider at CERN, allow researchers to smash protons together and analyze the debris left behind by such collisions. Physicists at Los Alamos National Laboratory, however, are taking a different approach: they are using computers. In collaboration with colleagues at University of California San Diego,more » the Los Alamos researchers developed a computer code, called BURST, that can simulate conditions during the first few minutes of cosmological evolution.« less

Working Group Report: Higgs Boson

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dawson, Sally; Gritsan, Andrei; Logan, Heather

2013-10-30

This report summarizes the work of the Energy Frontier Higgs Boson working group of the 2013 Community Summer Study (Snowmass). We identify the key elements of a precision Higgs physics program and document the physics potential of future experimental facilities as elucidated during the Snowmass study. We study Higgs couplings to gauge boson and fermion pairs, double Higgs production for the Higgs self-coupling, its quantum numbers and $CP$-mixing in Higgs couplings, the Higgs mass and total width, and prospects for direct searches for additional Higgs bosons in extensions of the Standard Model. Our report includes projections of measurement capabilities frommore » detailed studies of the Compact Linear Collider (CLIC), a Gamma-Gamma Collider, the International Linear Collider (ILC), the Large Hadron Collider High-Luminosity Upgrade (HL-LHC), Very Large Hadron Colliders up to 100 TeV (VLHC), a Muon Collider, and a Triple-Large Electron Positron Collider (TLEP).« less

Sticking with SUSY

NASA Astrophysics Data System (ADS)

Gates, S. James, Jr.

2014-10-01

When CERN's Large Hadron Collider failed to uncover evidence of new "superpartner" particles during its first run, some claimed that the theory that predicts them - known as supersymmetry, or SUSY - should be abandoned. S James Gates, Jr, however, argues that giving up on SUSY now would be like concluding that giant sequoia trees do not exist after surveying only the east coast of North America, and that there is more at stake than meets the eye.

Smashing Protons to Smithereens

ScienceCinema

Pleier, Marc-André

2018-01-05

Pleier discusses the extraordinary research taking place at the Large Hadron Collider (LHC) — the world’s newest, biggest, and highest energy particle accelerator located at CERN. Pleier is one of hundreds of researchers from around the world working on ATLAS, a seven-story particle detector positioned at a point where the LHC’s oppositely circulating beams of protons slam into one another head-on.

A test of the Feynman scaling in the fragmentation region

NASA Technical Reports Server (NTRS)

Doke, T.; Innocente, V.; Kasahara, K.; Kikuchi, J.; Kashiwagi, T.; Lanzano, S.; Masuda, K.; Murakami, H.; Muraki, Y.; Nakada, T.

1985-01-01

The result of the direct measurement of the fragmentation region will be presented. The result will be obtained at the CERN proton-antiproton collider, being exposured the Silicon calorimeters inside beam pipe. This experiment clarifies a long riddle of cosmic ray physics, whether the Feynman scaling does villate at the fragmentation region or the Iron component is increasing at 10 to the 15th power eV.

Particle production at energies available at the CERN Large Hadron Collider within an evolutionary model

NASA Astrophysics Data System (ADS)

Sinyukov, Yu. M.; Shapoval, V. M.

2018-06-01

The particle yields and particle number ratios in Pb+Pb collisions at the CERN Large Hadron Collider (LHC) energy √{sN N}=2.76 TeV are described within the integrated hydrokinetic model (iHKM) at two different equations of state (EoS) for quark-gluon matter and the two corresponding hadronization temperatures T =165 MeV and T =156 MeV. The role of particle interactions at the final afterburner stage of the collision in the particle production is investigated by means of comparison of the results of full iHKM simulations with those where the annihilation and other inelastic processes (except for resonance decays) are switched off after hadronization/particlization, similarly as in the thermal models. An analysis supports the picture of continuous chemical freeze-out in the sense that the corrections to the sudden chemical freeze-out results, which arise because of the inelastic reactions at the subsequent evolution times, are noticeable and improve the description of particle number ratios. An important observation is that, although the particle number ratios with switched-off inelastic reactions are quite different at different particlization temperatures which are adopted for different equations of state to reproduce experimental data, the complete iHKM calculations bring very close results in both cases.

DOE Office of Scientific and Technical Information (OSTI.GOV)

campbell, myron

To create a research and study abroad program that would allow U.S. undergraduate students access to the world-leading research facilities at the European Organization for Nuclear Research (CERN), the World Health Organization, various operations of the United Nations and other international organizations based in Geneva.The proposal is based on the unique opportunities currently existing in Geneva. The Large Hadron Collider (LHC) is now operational at CERN, data are being collected, and research results are already beginning to emerge. At the same time, a related reduction of activity at U.S. facilities devoted to particle physics is expected. In addition, the U.S.more » higher-education community has an ever-increasing focus on international organizations dealing with world health pandemics, arms control and human rights, a nexus also centered in Geneva.« less

Calculations of safe collimator settings and β* at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Bruce, R.; Assmann, R. W.; Redaelli, S.

2015-06-01

The first run of the Large Hadron Collider (LHC) at CERN was very successful and resulted in important physics discoveries. One way of increasing the luminosity in a collider, which gave a very significant contribution to the LHC performance in the first run and can be used even if the beam intensity cannot be increased, is to decrease the transverse beam size at the interaction points by reducing the optical function β*. However, when doing so, the beam becomes larger in the final focusing system, which could expose its aperture to beam losses. For the LHC, which is designed to store beams with a total energy of 362 MJ, this is critical, since the loss of even a small fraction of the beam could cause a magnet quench or even damage. Therefore, the machine aperture has to be protected by the collimation system. The settings of the collimators constrain the maximum beam size that can be tolerated and therefore impose a lower limit on β*. In this paper, we present calculations to determine safe collimator settings and the resulting limit on β*, based on available aperture and operational stability of the machine. Our model was used to determine the LHC configurations in 2011 and 2012 and it was found that β* could be decreased significantly compared to the conservative model used in 2010. The gain in luminosity resulting from the decreased margins between collimators was more than a factor 2, and a further contribution from the use of realistic aperture estimates based on measurements was almost as large. This has played an essential role in the rapid and successful accumulation of experimental data in the LHC.

Reaching record-low β* at the CERN Large Hadron Collider using a novel scheme of collimator settings and optics

NASA Astrophysics Data System (ADS)

Bruce, R.; Bracco, C.; De Maria, R.; Giovannozzi, M.; Mereghetti, A.; Mirarchi, D.; Redaelli, S.; Quaranta, E.; Salvachua, B.

2017-03-01

The Large Hadron Collider (LHC) at CERN is built to collide intense proton beams with an unprecedented energy of 7 TeV. The design stored energy per beam of 362 MJ makes the LHC beams highly destructive, so that any beam losses risk to cause quenches of superconducting magnets or damage to accelerator components. Collimators are installed to protect the machine and they define a minimum normalized aperture, below which no other element is allowed. This imposes a limit on the achievable luminosity, since when squeezing β* (the β-function at the collision point) to smaller values for increased luminosity, the β-function in the final focusing system increases. This leads to a smaller normalized aperture that risks to go below the allowed collimation aperture. In the first run of the LHC, this was the main limitation on β*, which was constrained to values above the design specification. In this article, we show through theoretical and experimental studies how tighter collimator openings and a new optics with specific phase-advance constraints allows a β* as small as 40 cm, a factor 2 smaller than β*=80 cm used in 2015 and significantly below the design value β*=55 cm, in spite of a lower beam energy. The proposed configuration with β*=40 cm has been successfully put into operation and has been used throughout 2016 as the LHC baseline. The decrease in β* compared to 2015 has been an essential contribution to reaching and surpassing, in 2016, the LHC design luminosity for the first time, and to accumulating a record-high integrated luminosity of around 40 fb-1 in one year, in spite of using less bunches than in the design.

Simulations and measurements of beam loss patterns at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Bruce, R.; Assmann, R. W.; Boccone, V.; Bracco, C.; Brugger, M.; Cauchi, M.; Cerutti, F.; Deboy, D.; Ferrari, A.; Lari, L.; Marsili, A.; Mereghetti, A.; Mirarchi, D.; Quaranta, E.; Redaelli, S.; Robert-Demolaize, G.; Rossi, A.; Salvachua, B.; Skordis, E.; Tambasco, C.; Valentino, G.; Weiler, T.; Vlachoudis, V.; Wollmann, D.

2014-08-01

The CERN Large Hadron Collider (LHC) is designed to collide proton beams of unprecedented energy, in order to extend the frontiers of high-energy particle physics. During the first very successful running period in 2010-2013, the LHC was routinely storing protons at 3.5-4 TeV with a total beam energy of up to 146 MJ, and even higher stored energies are foreseen in the future. This puts extraordinary demands on the control of beam losses. An uncontrolled loss of even a tiny fraction of the beam could cause a superconducting magnet to undergo a transition into a normal-conducting state, or in the worst case cause material damage. Hence a multistage collimation system has been installed in order to safely intercept high-amplitude beam protons before they are lost elsewhere. To guarantee adequate protection from the collimators, a detailed theoretical understanding is needed. This article presents results of numerical simulations of the distribution of beam losses around the LHC that have leaked out of the collimation system. The studies include tracking of protons through the fields of more than 5000 magnets in the 27 km LHC ring over hundreds of revolutions, and Monte Carlo simulations of particle-matter interactions both in collimators and machine elements being hit by escaping particles. The simulation results agree typically within a factor 2 with measurements of beam loss distributions from the previous LHC run. Considering the complex simulation, which must account for a very large number of unknown imperfections, and in view of the total losses around the ring spanning over 7 orders of magnitude, we consider this an excellent agreement. Our results give confidence in the simulation tools, which are used also for the design of future accelerators.

1995 second modulator-klystron workshop: A modulator-klystron workshop for future linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

NONE

1996-03-01

This second workshop examined the present state of modulator design and attempted an extrapolation for future electron-positron linear colliders. These colliders are currently viewed as multikilometer-long accelerators consisting of a thousand or more RF sources with 500 to 1,000, or more, pulsed power systems. The workshop opened with two introductory talks that presented the current approaches to designing these linear colliders, the anticipated RF sources, and the design constraints for pulse power. The cost of main AC power is a major economic consideration for a future collider, consequently the workshop investigated efficient modulator designs. Techniques that effectively apply the artmore » of power conversion, from the AC mains to the RF output, and specifically, designs that generate output pulses with very fast rise times as compared to the flattop. There were six sessions that involved one or more presentations based on problems specific to the design and production of thousands of modulator-klystron stations, followed by discussion and debate on the material.« less

Al-Qaeda arrest casts shadow over the LHC

NASA Astrophysics Data System (ADS)

Dacey, James

2009-11-01

CERN remains on course for the imminent switch-on of the Large Hadron Collider (LHC) despite the media frenzy following the recent arrest of a physicist who had been working at the facility. The researcher in question is a 32-year-old man of Algerian descent who is expected to face trial in France - the country in which he was arrested. His name is yet to be formally identified under French judicial rules.

The ATLAS Experiment: Mapping the Secrets of the Universe (LBNL Summer Lecture Series)

ScienceCinema

Barnett, Michael [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Physics Division

2018-01-12

Summer Lecture Series 2007: Michael Barnett of Berkeley Lab's Physics Division discusses the ATLAS Experiment at the European Laboratory for Particle Physics' (CERN) Large Hadron Collider. The collider will explore the aftermath of collisions at the highest energy ever produced in the lab, and will recreate the conditions of the universe a billionth of a second after the Big Bang. The ATLAS detector is half the size of the Notre Dame Cathedral and required 2000 physicists and engineers from 35 countries for its construction. Its goals are to examine mini-black holes, identify dark matter, understand antimatter, search for extra dimensions of space, and learn about the fundamental forces that have shaped the universe since the beginning of time and will determine its fate.

Preface

NASA Astrophysics Data System (ADS)

Buthelezi, Zinhle; Cleymans, Jean; Dietel, Tom; Förtsch, Siegfried; Horowitz, W. A.; Steinberg, Peter; Weigert, Heribert

2014-12-01

From November 4th-8th 2013, South Africa hosted the "6th International Conference on Hard and Electromagnetic Probes of High-Energy Nuclear Collisions (Hard Probes 2013)" in the beautiful Cape Winelands at the Stellenbosch Institute for Advanced Studies. This is the preëminent conference series for scientists from around the world to disseminate, discuss, and collaborate on their research on the Hard Probes of heavy ion collisions. The goal is a quantitative understanding of the nontrivial, emergent, many-body dynamics of hot and dense non-Abelian Quantum Chromodynamics (QCD), the quark-gluon plasma (QGP). This matter permeated the universe a microsecond after the Big Bang and is produced at facilities such as the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) in New York and at the Large Hadron Collider (LHC) at CERN in Geneva.

Higgs, SUSY and the standard model at /γγ colliders

NASA Astrophysics Data System (ADS)

Hagiwara, Kaoru

2001-10-01

In this report, I surveyed physics potential of the γγ option of a linear e +e - collider with the following questions in mind: What new discovery can be expected at a γγ collider in addition to what will be learned at its ' parent' e +e -linear collider? By taking account of the hard energy spectrum and polarization of colliding photons, produced by Compton back-scattering of laser light off incoming e - beams, we find that a γγ collider is most powerful when new physics appears in the neutral spin-zero channel at an invariant mass below about 80% of the c.m. energy of the colliding e -e - system. If a light Higgs boson exists, its properties can be studied in detail, and if its heavier partners or a heavy Higgs boson exists in the above mass range, they may be discovered at a γγ collider. CP property of the scalar sector can be explored in detail by making use of linear polarization of the colliding photons, decay angular correlations of final state particles, and the pattern of interference with the Standard Model amplitudes. A few comments are given for SUSY particle studies at a γγ collider, where a pair of charged spinless particles is produced in the s-wave near the threshold. Squark-onium may be discovered. An e ±γ collision mode may measure the Higgs- Z-γ coupling accurately and probe flavor oscillations in the slepton sector. As a general remark, all the Standard Model background simulation tools should be prepared in the helicity amplitude level, so that simulation can be performed for an arbitrary set of Stokes parameters of the incoming photon beams.

The International Linear Collider

NASA Astrophysics Data System (ADS)

List, Benno

2014-04-01

The International Linear Collider (ILC) is a proposed e+e- linear collider with a centre-of-mass energy of 200-500 GeV, based on superconducting RF cavities. The ILC would be an ideal machine for precision studies of a light Higgs boson and the top quark, and would have a discovery potential for new particles that is complementary to that of LHC. The clean experimental conditions would allow the operation of detectors with extremely good performance; two such detectors, ILD and SiD, are currently being designed. Both make use of novel concepts for tracking and calorimetry. The Japanese High Energy Physics community has recently recommended to build the ILC in Japan.

Optical fibres in the radiation environment of CERN

NASA Astrophysics Data System (ADS)

Guillermain, E.

2017-11-01

CERN, the European Organization for Nuclear Research (in Geneva, Switzerland), is home to a complex scientific instrument: the 27-kilometre Large Hadron Collider (LHC) collides beams of high-energy particles at close to the speed of light. Optical fibres are widely used at CERN, both in surface areas (e.g. for inter-building IT networks) and in the accelerator complex underground (e.g. for cryogenics, vacuum, safety systems). Optical fibres in the accelerator are exposed to mixed radiation fields (mainly composed of protons, pions, neutrons and other hadrons, gamma rays and electrons), with dose rates depending on the particular installation zone, and with radiation levels often significantly higher than those encountered in space. In the LHC and its injector chain radiation levels range from relatively low annual doses of a few Gy up to hundreds of kGy. Optical fibres suffer from Radiation Induced Attenuation (RIA, expressed in dB per unit length) that affect light transmission and which depends on the irradiation conditions (e.g. dose rate, total dose, temperature). In the CERN accelerator complex, the failure of an optical link can affect the proper functionality of control or monitoring systems and induce the interruption of the accelerator operation. The qualification of optical fibres for installation in critical radiation areas is therefore crucial. Thus, all optical fibre types installed in radiation areas at CERN are subject to laboratory irradiation tests, in order to evaluate their RIA at different total dose and dose rates. This allows the selection of the appropriate optical fibre type (conventional or radiation resistant) compliant with the requirements of each installation. Irradiation tests are performed in collaboration with Fraunhofer INT (irradiation facilities and expert team in Euskirchen, Germany). Conventional off-the-shelf optical fibres can be installed for optical links exposed to low radiation levels (i.e. annual dose typically below few kGy). Nevertheless, the conventional optical fibres must be carefully qualified as a spread in RIA of factor 10 is observed among optical fibres of different types and dopants. In higher radiation areas, special radiation resistant optical fibres are installed. For total dose above 1 kGy, the RIA of these special optical fibres is at least 10 times lower than the conventional optical fibres RIA at same irradiation conditions. 2400 km of these special radiation resistant optical fibres were recently procured at CERN. As part of this procurement process, a quality assurance plan including the irradiation testing of all 65 produced batches was set up. This presentation will review the selection process of the appropriate optical fibre types to be installed in the radiation environment of CERN. The methodology for choosing the irradiation parameters for the laboratory tests will be discussed together with an overview of the RIA of different optical fibre types under several irradiation conditions.

A plasma lens for a linear collider final focus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Norem, J.; Cline, D.B.; Cole, B.

High density relativistic beams propagating in a plasma are affected by fields induced by plasma motion. We consider the possible use of a plasma cell very close to the interaction point of a linear collider where the self-pinch induced in the relativistic beams can be used to increase the luminosity of colliding beams. We describe the benefits of this self-pinch, as well as some engineering details on the production of the required plasma. 18 refs., 5 figs., 1 tab.

PREFACE: Hot Quarks 2012: Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions

NASA Astrophysics Data System (ADS)

Bleicher, Markus; Caines, Helen; Calderón de la Barca Sanchez, Manuel; Fries, Rainer; Granier de Cassagnac, Raphaël; Hippolyte, Boris; Mischke, André; Mócsy, Ágnes; Petersen, Hannah; Ruan, Lijuan; Salgado, Carlos A.

2013-09-01

The 5th edition of the Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions (Hot Quarks 2012) was held in Copamarina, Puerto Rico from 14-20 October 2012. As in previous years, this meeting gathered more than 70 participants in the early years of their scientific careers. This issue contains the proceedings of the workshop. As in the past, the Hot Quarks workshop offered a unique atmosphere for a lively discussion and interpretation of the current measurements from high energy nuclear collisions. Recent results and upgrades at CERN's Large Hadron Collider (LHC) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) were presented. Measurements from the proton-led run at the CERN-LHC were shown for the first time at this meeting. Recent theoretical developments were also extensively discussed, as well as the proposals for future facilities such as the Facility for Antiproton and Ion Research (FAIR) at Darmstadt, the Electron-Ion Collider at Brookhaven, and the LHeC. The conference's goal to provide a platform for young researchers to learn and foster their interactions was successfully met. We wish to thank the sponsors of the Hot Quarks 2012 Conference, who supported the authors of this volume: Brookhaven National Laboratory (USA), European Laboratory for Particle Physics CERN (Switzerland), European Research Council (EU), ExtreMe Matter Institute EMMI (Germany), Helmholtz International Center for FAIR (Germany), IN2P3/CNRS (France) and the European Research Council via grant #259612, Lawrence Berkeley National Laboratory (USA), Lawrence Livermore National Laboratory (USA), Los Alamos National Laboratory (USA), National Science Foundation (USA), and Netherlands Organization for Scientific Research (Netherlands). Marcus BleicherAndré Mischke Goethe-University Frankfurt and HIC4FAIRUtrecht University and Nikhef Amsterdam GermanyThe Netherlands Helen CainesÁgnes Mócsy Yale UniversityPratt Institute and Brookhaven National Laboratory USAUSA Manuel Calderón de la Barca SánchezHannah Petersen UC DavisFIAS USAGermany Rainer J FriesLijuan Ruan Texas A&M UniversityBrookhaven National Laboratory USAUSA Raphaël Granier de CassagnacCarlos A Salgado CNRS-IN2P3 and Ëcole polytechniqueUniversidade de Santiago de Compostela FranceSpain Boris Hippolyte CNRS-IN2P3 and Université de Strasbourg France The PDF also contains the conference poster.

Performance of the Prototype Readout System for the CMS Endcap Hadron Calorimeter Upgrade

NASA Astrophysics Data System (ADS)

Chaverin, Nate; Dittmann, Jay; Hatakeyama, Kenichi; Pastika, Nathaniel; CMS Collaboration

2016-03-01

The Compact Muon Solenoid (CMS) experiment at the CERN Large Hadron Collider (LHC) will upgrade the photodetectors and readout systems of the endcap hadron calorimeter during the technical stop scheduled for late 2016 and early 2017. A major milestone for this project was a highly successful testbeam run at CERN in August 2015. The testbeam run served as a full integration test of the electronics, allowing a study of the response of the preproduction electronics to the true detector light profile, as well as a test of the light yield of various new plastic scintillator materials. We present implications for the performance of the hadron calorimeter front-end electronics based on testbeam data, and we report on the production status of various components of the system in preparation for the upgrade.

First results from the CERN axion solar telescope.

PubMed

Zioutas, K; Andriamonje, S; Arsov, V; Aune, S; Autiero, D; Avignone, F T; Barth, K; Belov, A; Beltrán, B; Bräuninger, H; Carmona, J M; Cebrián, S; Chesi, E; Collar, J I; Creswick, R; Dafni, T; Davenport, M; Di Lella, L; Eleftheriadis, C; Englhauser, J; Fanourakis, G; Farach, H; Ferrer, E; Fischer, H; Franz, J; Friedrich, P; Geralis, T; Giomataris, I; Gninenko, S; Goloubev, N; Hasinoff, M D; Heinsius, F H; Hoffmann, D H H; Irastorza, I G; Jacoby, J; Kang, D; Königsmann, K; Kotthaus, R; Krcmar, M; Kousouris, K; Kuster, M; Lakić, B; Lasseur, C; Liolios, A; Ljubicić, A; Lutz, G; Luzón, G; Miller, D W; Morales, A; Morales, J; Mutterer, M; Nikolaidis, A; Ortiz, A; Papaevangelou, T; Placci, A; Raffelt, G; Ruz, J; Riege, H; Sarsa, M L; Savvidis, I; Serber, W; Serpico, P; Semertzidis, Y; Stewart, L; Vieira, J D; Villar, J; Walckiers, L; Zachariadou, K

2005-04-01

Hypothetical axionlike particles with a two-photon interaction would be produced in the sun by the Primakoff process. In a laboratory magnetic field ("axion helioscope"), they would be transformed into x-rays with energies of a few keV. Using a decommissioned Large Hadron Collider test magnet, the CERN Axion Solar Telescope ran for about 6 months during 2003. The first results from the analysis of these data are presented here. No signal above background was observed, implying an upper limit to the axion-photon coupling g(agamma)<1.16x10(-10) GeV-1 at 95% C.L. for m(a) less, similar 0.02 eV. This limit, assumption-free, is comparable to the limit from stellar energy-loss arguments and considerably more restrictive than any previous experiment over a broad range of axion masses.

How to deal with petabytes of data: the LHC Grid project

NASA Astrophysics Data System (ADS)

Britton, D.; Lloyd, S. L.

2014-06-01

We review the Grid computing system developed by the international community to deal with the petabytes of data coming from the Large Hadron Collider at CERN in Geneva with particular emphasis on the ATLAS experiment and the UK Grid project, GridPP. Although these developments were started over a decade ago, this article explains their continued relevance as part of the ‘Big Data’ problem and how the Grid has been forerunner of today's cloud computing.

Quantifying properties of hot and dense QCD matter through systematic model-to-data comparison

DOE PAGES

Bernhard, Jonah E.; Marcy, Peter W.; Coleman-Smith, Christopher E.; ...

2015-05-22

We systematically compare an event-by-event heavy-ion collision model to data from the CERN Large Hadron Collider. Using a general Bayesian method, we probe multiple model parameters including fundamental quark-gluon plasma properties such as the specific shear viscosity η/s, calibrate the model to optimally reproduce experimental data, and extract quantitative constraints for all parameters simultaneously. Furthermore, the method is universal and easily extensible to other data and collision models.

Strangeness Production in the ALICE Experiment at the LHC

NASA Astrophysics Data System (ADS)

Johnson, Harold; Fenner, Kiara; Harton, Austin; Garcia-Solis, Edmundo; Soltz, Ron

2015-04-01

The study of strange particle production is an important tool in understanding the properties of a hot and dense medium, the quark-gluon plasma, created in heavy-ion collisions at ultra-relativistic energies. This quark-gluon plasma (QGP) is believed to have been present just after the big bang. The standard model of physics contains six types of quarks. Strange quarks are not among the valence quarks found in protons and neutrons. Strange quark production is sensitive to the extremely high temperatures of the QGP. CERN's Large Hadron Collider accelerates particles to nearly the speed of light before colliding them to create this QGP state. In the results of high-energy particle collisions, hadrons are formed out of quarks and gluons when cooling from extremely high temperatures. Jets are a highly collimated cone of particles coming from the hadronization of a single quark or gluon. Understanding jet interactions may give us clues about the QGP. Using FastJet (a popular jet finder algorithm), we extracted strangeness, or strange particle characteristics of jets contained within proton-proton collisions during our research at CERN. We have identified jets with and without strange particles in proton-proton collisions and we will present a comparison of pT spectra in both cases. This material is based upon work supported by the National Science Foundation under grants PHY-1305280 and PHY-1407051.

High energy density physics effects predicted in simulations of the CERN HiRadMat beam-target interaction experiments

NASA Astrophysics Data System (ADS)

Tahir, N. A.; Burkart, F.; Schmidt, R.; Shutov, A.; Wollmann, D.; Piriz, A. R.

2016-12-01

Experiments have been done at the CERN HiRadMat (High Radiation to Materials) facility in which large cylindrical copper targets were irradiated with 440 GeV proton beam generated by the Super Proton Synchrotron (SPS). The primary purpose of these experiments was to confirm the existence of hydrodynamic tunneling of ultra-relativistic protons and their hadronic shower in solid materials, that was predicted by previous numerical simulations. The experimental measurements have shown very good agreement with the simulation results. This provides confidence in our simulations of the interaction of the 7 TeV LHC (Large Hadron Collider) protons and the 50 TeV Future Circular Collider (FCC) protons with solid materials, respectively. This work is important from the machine protection point of view. The numerical simulations have also shown that in the HiRadMat experiments, a significant part of thetarget material is be converted into different phases of High Energy Density (HED) matter, including two-phase solid-liquid mixture, expanded as well as compressed hot liquid phases, two-phase liquid-gas mixture and gaseous state. The HiRadMat facility is therefore a unique ion beam facility worldwide that is currently available for studying the thermophysical properties of HED matter. In the present paper we discuss the numerical simulation results and present a comparison with the experimental measurements.

Revised LHC deal quiets congress

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lawler, A.

The roughest part of the ride may be over for U.S. physicists who want to participate in the Large Hadron Collider (LHC), the $5 billion accelerator planned for CERN in Geneva. They have found themselves on a political roller coaster for the past few months. This week, U.S. and European negotiators were putting the final touches on a revamped agreement that should pave the way for the United States to help pay for construction of the accelerator and its two main detectors, and guarantee U.S. scientists a role in research on the machine. The trouble began in March, when Representativemore » Joe Barton (R-TX) declared war on a proposed $530 million U.S. contribution to the new facility, slated for completion in 2005. Barton and many other members of Congress were still smarting from what they said was a lack of European support for the canceled Superconducting Super Collider that was being built in Barton`s backyard. Representative James Sensenbrenner (R-WI), who chairs the House Science Committee, led the charge to alter a draft agreement initialed this winter by Department of Energy (DOE) and CERN officials that spelled out the details of U.S. participation. After hurried negotiations, both sides have sharpened the agreement to address the lawmakers` concerns. The new deal, says Energy Secretary Federico Pena, {open_quotes}has made that project even better.{close_quotes}« less

Submicron multi-bunch BPM for CLIC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schmickler, H.; Soby, L.; /CERN

2010-08-01

A common-mode free cavity BPM is currently under development at Fermilab within the ILC-CLIC collaboration. This monitor will be operated in a CLIC Main Linac multi-bunch regime, and needs to provide both, high spatial and time resolution. We present the design concept, numerical analysis, investigation on tolerances and error effects, as well as simulations on the signal response applying a multi-bunch stimulus. The proposed CERN linear collider (CLIC) requires a very precise measurement of beam trajectory to preserve the low emittance when transporting the beam through the Main Linac. An energy chirp within the bunch train will be applied tomore » measure and minimize the dispersion effects, which require high resolution (in both, time and space) beam position monitors (BPM) along the beam-line. We propose a low-Q waveguide loaded TM{sub 110} dipole mode cavity as BPM, which is complemented by a TM{sub 010} monopole mode resonator of same resonant frequency for reference signal purposes. The design is based on a well known TM{sub 110} selective mode coupling idea.« less

Theoretical and Computational Investigation of High-Brightness Beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Chiping

Theoretical and computational investigations of adiabatic thermal beams have been carried out in parameter regimes relevant to the development of advanced high-brightness, high-power accelerators for high-energy physics research and for various applications such as light sources. Most accelerator applications require high-brightness beams. This is true for high-energy accelerators such as linear colliders. It is also true for energy recovery linacs (ERLs) and free electron lasers (FELs) such as x-ray free electron lasers (XFELs). The breakthroughs and highlights in our research in the period from February 1, 2013 to November 30, 2013 were: a) Completion of a preliminary theoretical and computationalmore » study of adiabatic thermal Child-Langmuir flow (Mok, 2013); and b) Presentation of an invited paper entitled ?Adiabatic Thermal Beams in a Periodic Focusing Field? at Space Charge 2013 Workshop, CERN, April 16-19, 2013 (Chen, 2013). In this report, an introductory background for the research project is provided. Basic theory of adiabatic thermal Child-Langmuir flow is reviewed. Results of simulation studies of adiabatic thermal Child-Langmuir flows are discussed.« less

Development of semiconductor tracking: The future linear collider case

NASA Astrophysics Data System (ADS)

Savoy-Navarro, Aurore

2011-04-01

An active R&D on silicon tracking for the linear collider, SiLC, is pursued since several years to develop the new generation of large area silicon trackers for the future linear collider(s). The R&D objectives on new sensors, new front end processing of the signal, and the related mechanical and integration challenges for building such large detectors within the proposed detector concepts are described. Synergies and differences with the LHC construction and upgrades are explained. The differences between the linear collider projects, namely the international linear collider, ILC, and the compact linear collider, CLIC, are discussed as well. Two final objectives are presented for the construction of this important sub-detector for the future linear collider experiments: a relatively short term design based on micro-strips combined or not with a gaseous central tracker and a longer term design based on an all-pixel tracker.The R&D objectives on sensors include single sided micro-strips as baseline for the shorter term with the strips from large wafers (at least 6 in), 200 μm thick, 50 μm pitch and the edgeless and alignment friendly options. This work is conducted by SiLC in collaboration with three technical research centers in Italy, Finland, and Spain and HPK. SiLC is studied as well, using advanced Si sensor technologies for higher granularity trackers especially short strips and pixels all based on 3D technology. New Deep Sub-Micron CMOS mix mode (analog and digital) FE and readout electronics are developed to fully process the detector signals currently adapted to the ILC cycle. It is a high-level processing and a fully programmable ASIC; highly fault tolerant. In its latest version, handling 128 channels will equip these next coming years larger size silicon tracking prototypes at test beams. Connection of the FEE chip on the silicon detector especially in the strip case is a major issue. Very preliminary results with inline pitch adapter based on wiring were just achieved. Bump-bonding or 3D vertical interconnect is the other SiLC R&D objective. The goal is to simplify the overall architecture and decrease the material budget of these devices. Three tracking concepts are briefly discussed, two of which are part of the ILC Letter of Intent of the ILD and SiD detector concepts. These last years, SiLC successfully performed beam tests to experience and test these R&D lines.

The discovery of the Higgs boson at the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Nisati, A.; Tonelli, G.

2015-11-01

This paper summarises the work done by the ATLAS and CMS collaborations, and by the teams of the Large Hadron Collider at CERN, that led to the discovery of a new particle, with mass near 125GeV and properties consistent with the ones predicted for the Standard Model Higgs boson. An overview of the Standard Model, with a description of the role of the Higgs boson in the theory, and a summary of the searches for this particle prior to the LHC operations is also given. The paper presents the results obtained by ATLAS and CMS from the analysis of the full data set produced in the first physics run of LHC. After a short discussion on the implications of the discovery, the future prospects for the precision study of the new particle are lastly discussed.

Net-charge fluctuations in Pb-Pb collisions at sqrt[sNN]=2.76  TeV.

PubMed

Abelev, B; Adam, J; Adamová, D; Adare, A M; Aggarwal, M M; Aglieri Rinella, G; Agocs, A G; Agostinelli, A; Aguilar Salazar, S; Ahammed, Z; Ahmad Masoodi, A; Ahmad, N; Ahn, S A; Ahn, S U; Akindinov, A; Aleksandrov, D; Alessandro, B; Alfaro Molina, R; Alici, A; Alkin, A; Almaráz Aviña, E; Alme, J; Alt, T; Altini, V; Altinpinar, S; Altsybeev, I; Andrei, C; Andronic, A; Anguelov, V; Anielski, J; Anson, C; Antičić, T; Antinori, F; Antonioli, P; Aphecetche, L; Appelshäuser, H; Arbor, N; Arcelli, S; Arend, A; Armesto, N; Arnaldi, R; Aronsson, T; Arsene, I C; Arslandok, M; Asryan, A; Augustinus, A; Averbeck, R; Awes, T C; Äystö, J; Azmi, M D; Bach, M; Badalà, A; Baek, Y W; Bailhache, R; Bala, R; Baldini Ferroli, R; Baldisseri, A; Baldit, A; Baltasar Dos Santos Pedrosa, F; Bán, J; Baral, R C; Barbera, R; Barile, F; Barnaföldi, G G; Barnby, L S; Barret, V; Bartke, J; Basile, M; Bastid, N; Basu, S; Bathen, B; Batigne, G; Batyunya, B; Baumann, C; Bearden, I G; Beck, H; Behera, N K; Belikov, I; Bellini, F; Bellwied, R; Belmont-Moreno, E; Bencedi, G; Beole, S; Berceanu, I; Bercuci, A; Berdnikov, Y; Berenyi, D; Bergognon, A A E; Berzano, D; Betev, L; Bhasin, A; Bhati, A K; Bhom, J; Bianchi, L; Bianchi, N; Bianchin, C; Bielčík, J; Bielčíková, J; Bilandzic, A; Bjelogrlic, S; Blanco, F; Blanco, F; Blau, D; Blume, C; Boccioli, M; Bock, N; Böttger, S; Bogdanov, A; Bøggild, H; Bogolyubsky, M; Boldizsár, L; Bombara, M; Book, J; Borel, H; Borissov, A; Bose, S; Bossú, F; Botje, M; Boyer, B; Braidot, E; Braun-Munzinger, P; Bregant, M; Breitner, T; Browning, T A; Broz, M; Brun, R; Bruna, E; Bruno, G E; Budnikov, D; Buesching, H; Bufalino, S; Bugaiev, K; Busch, O; Buthelezi, Z; Caballero Orduna, D; Caffarri, D; Cai, X; Caines, H; Calvo Villar, E; Camerini, P; Canoa Roman, V; Cara Romeo, G; Carena, F; Carena, W; Carlin Filho, N; Carminati, F; Carrillo Montoya, C A; Casanova Díaz, A; Castillo Castellanos, J; Castillo Hernandez, J F; Casula, E A R; Catanescu, V; Cavicchioli, C; Ceballos Sanchez, C; Cepila, J; Cerello, P; Chang, B; Chapeland, S; Charvet, J L; Chattopadhyay, S; Chattopadhyay, S; Chawla, I; Cherney, M; Cheshkov, C; Cheynis, B; Chibante Barroso, V; Chinellato, D D; Chochula, P; Chojnacki, M; Choudhury, S; Christakoglou, P; Christensen, C H; Christiansen, P; Chujo, T; Chung, S U; Cicalo, C; Cifarelli, L; Cindolo, F; Cleymans, J; Coccetti, F; Colamaria, F; Colella, D; Conesa Balbastre, G; Conesa del Valle, Z; Constantin, P; Contin, G; Contreras, J G; Cormier, T M; Corrales Morales, Y; Cortese, P; Cortés Maldonado, I; Cosentino, M R; Costa, F; Cotallo, M E; Crescio, E; Crochet, P; Cruz Alaniz, E; Cuautle, E; Cunqueiro, L; Dainese, A; Dalsgaard, H H; Danu, A; Das, D; Das, I; Das, K; Dash, S; Dash, A; De, S; de Barros, G O V; De Caro, A; de Cataldo, G; de Cuveland, J; De Falco, A; De Gruttola, D; Delagrange, H; Deloff, A; Demanov, V; De Marco, N; Dénes, E; De Pasquale, S; Deppman, A; Erasmo, G D; de Rooij, R; Diaz Corchero, M A; Di Bari, D; Dietel, T; Di Liberto, S; Di Mauro, A; Di Nezza, P; Divià, R; Djuvsland, Ø; Dobrin, A; Dobrowolski, T; Domínguez, I; Dönigus, B; Dordic, O; Driga, O; Dubey, A K; Ducroux, L; Dupieux, P; Dutta Majumdar, M R; Dutta Majumdar, A K; Elia, D; Emschermann, D; Engel, H; Erdal, H A; Espagnon, B; Estienne, M; Esumi, S; Evans, D; Eyyubova, G; Fabris, D; Faivre, J; Falchieri, D; Fantoni, A; Fasel, M; Fearick, R; Fedunov, A; Fehlker, D; Feldkamp, L; Felea, D; Fenton-Olsen, B; Feofilov, G; Fernández Téllez, A; Ferretti, A; Ferretti, R; Figiel, J; Figueredo, M A S; Filchagin, S; Finogeev, D; Fionda, F M; Fiore, E M; Floris, M; Foertsch, S; Foka, P; Fokin, S; Fragiacomo, E; Frankenfeld, U; Fuchs, U; Furget, C; Fusco Girard, M; Gaardhøje, J J; Gagliardi, M; Gago, A; Gallio, M; Gangadharan, D R; Ganoti, P; Garabatos, C; Garcia-Solis, E; Garishvili, I; Gerhard, J; Germain, M; Geuna, C; Gheata, A; Gheata, M; Ghidini, B; Ghosh, P; Di Giglio, C; Gianotti, P; Girard, M R; Giubellino, P; Gladysz-Dziadus, E; Glässel, P; Gomez, R; Gonschior, A; Ferreiro, E G; González-Trueba, L H; González-Zamora, P; Gorbunov, S; Goswami, A; Gotovac, S; Grabski, V; Graczykowski, L K; Grajcarek, R; Grelli, A; Grigoras, C; Grigoras, A; Grigoriev, V; Grigoryan, A; Grigoryan, S; Grinyov, B; Grion, N; Gros, P; Grosse-Oetringhaus, J F; Grossiord, J-Y; Grosso, R; Guber, F; Guernane, R; Guerra Gutierrez, C; Guerzoni, B; Guilbaud, M; Gulbrandsen, K; Gunji, T; Gupta, A; Gupta, R; Gutbrod, H; Haaland, Ø; Hadjidakis, C; Haiduc, M; Hamagaki, H; Hamar, G; Han, B H; Hanratty, L D; Hansen, A; Harmanova, Z; Harris, J W; Hartig, M; Hasegan, D; Hatzifotiadou, D; Hayrapetyan, A; Heckel, S T; Heide, M; Helstrup, H; Herghelegiu, A; Herrera Corral, G; Herrmann, N; Hess, B A; Hetland, K F; Hicks, B; Hille, P T; Hippolyte, B; Horaguchi, T; Hori, Y; Hristov, P; Hřivnáčová, I; Huang, M; Humanic, T J; Hwang, D S; Ichou, R; Ilkaev, R; Ilkiv, I; Inaba, M; Incani, E; Innocenti, G M; Innocenti, P G; Ippolitov, M; Irfan, M; Ivan, C; Ivanov, V; Ivanov, M; Ivanov, A; Ivanytskyi, O; Jachołkowski, A; Jacobs, P M; Jang, H J; Jangal, S; Janik, M A; Janik, R; Jayarathna, P H S Y; Jena, S; Jha, D M; Jimenez Bustamante, R T; Jirden, L; Jones, P G; Jung, H; Jusko, A; Kaidalov, A B; Kakoyan, V; Kalcher, S; Kaliňák, P; Kalliokoski, T; Kalweit, A; Kanaki, K; Kang, J H; Kaplin, V; Karasu Uysal, A; Karavichev, O; Karavicheva, T; Karpechev, E; Kazantsev, A; Kebschull, U; Keidel, R; Khan, P; Khan, M M; Khan, S A; Khanzadeev, A; Kharlov, Y; Kileng, B; Kim, D W; Kim, M; Kim, M; Kim, S H; Kim, D J; Kim, S; Kim, J H; Kim, J S; Kim, B; Kim, T; Kirsch, S; Kisel, I; Kiselev, S; Kisiel, A; Klay, J L; Klein, J; Klein-Bösing, C; Kliemant, M; Kluge, A; Knichel, M L; Knospe, A G; Koch, K; Köhler, M K; Kolojvari, A; Kondratiev, V; Kondratyeva, N; Konevskikh, A; Korneev, A; Kour, R; Kowalski, M; Kox, S; Koyithatta Meethaleveedu, G; Kral, J; Králik, I; Kramer, F; Kraus, I; Krawutschke, T; Krelina, M; Kretz, M; Krivda, M; Krizek, F; Krus, M; Kryshen, E; Krzewicki, M; Kucheriaev, Y; Kuhn, C; Kuijer, P G; Kulakov, I; Kumar, J; Kurashvili, P; Kurepin, A B; Kurepin, A; Kuryakin, A; Kushpil, V; Kushpil, S; Kvaerno, H; Kweon, M J; Kwon, Y; Ladrón de Guevara, P; Lakomov, I; Langoy, R; La Pointe, S L; Lara, C; Lardeux, A; La Rocca, P; Lazzeroni, C; Lea, R; Le Bornec, Y; Lechman, M; Lee, S C; Lee, K S; Lee, G R; Lefèvre, F; Lehnert, J; Leistam, L; Lenhardt, M; Lenti, V; León, H; Leoncino, M; León Monzón, I; León Vargas, H; Lévai, P; Lien, J; Lietava, R; Lindal, S; Lindenstruth, V; Lippmann, C; Lisa, M A; Liu, L; Loenne, P I; Loggins, V R; Loginov, V; Lohn, S; Lohner, D; Loizides, C; Loo, K K; Lopez, X; López Torres, E; Løvhøiden, G; Lu, X-G; Luettig, P; Lunardon, M; Luo, J; Luparello, G; Luquin, L; Luzzi, C; Ma, R; Ma, K; Madagodahettige-Don, D M; Maevskaya, A; Mager, M; Mahapatra, D P; Maire, A; Malaev, M; Maldonado Cervantes, I; Malinina, L; Mal'Kevich, D; Malzacher, P; Mamonov, A; Manceau, L; Mangotra, L; Manko, V; Manso, F; Manzari, V; Mao, Y; Marchisone, M; Mareš, J; Margagliotti, G V; Margotti, A; Marín, A; Marin Tobon, C A; Markert, C; Martashvili, I; Martinengo, P; Martínez, M I; Martínez Davalos, A; Martínez García, G; Martynov, Y; Mas, A; Masciocchi, S; Masera, M; Masoni, A; Massacrier, L; Mastromarco, M; Mastroserio, A; Matthews, Z L; Matyja, A; Mayani, D; Mayer, C; Mazer, J; Mazzoni, M A; Meddi, F; Menchaca-Rocha, A; Mercado Pérez, J; Meres, M; Miake, Y; Milano, L; Milosevic, J; Mischke, A; Mishra, A N; Miśkowiec, D; Mitu, C; Mlynarz, J; Mohanty, B; Mohanty, A K; Molnar, L; Montaño Zetina, L; Monteno, M; Montes, E; Moon, T; Morando, M; Moreira De Godoy, D A; Moretto, S; Morsch, A; Muccifora, V; Mudnic, E; Muhuri, S; Mukherjee, M; Müller, H; Munhoz, M G; Musa, L; Musso, A; Nandi, B K; Nania, R; Nappi, E; Nattrass, C; Naumov, N P; Navin, S; Nayak, T K; Nazarenko, S; Nazarov, G; Nedosekin, A; Nicassio, M; Niculescu, M; Nielsen, B S; Niida, T; Nikolaev, S; Nikolic, V; Nikulin, S; Nikulin, V; Nilsen, B S; Nilsson, M S; Noferini, F; Nomokonov, P; Nooren, G; Novitzky, N; Nyanin, A; Nyatha, A; Nygaard, C; Nystrand, J; Ochirov, A; Oeschler, H; Oh, S; Oh, S K; Oleniacz, J; Oppedisano, C; Ortiz Velasquez, A; Ortona, G; Oskarsson, A; Ostrowski, P; Otwinowski, J; Oyama, K; Ozawa, K; Pachmayer, Y; Pachr, M; Padilla, F; Pagano, P; Paić, G; Painke, F; Pajares, C; Pal, S; Pal, S K; Palaha, A; Palmeri, A; Papikyan, V; Pappalardo, G S; Park, W J; Passfeld, A; Pastirčák, B; Patalakha, D I; Paticchio, V; Pavlinov, A; Pawlak, T; Peitzmann, T; Pereira Da Costa, H; Pereira De Oliveira Filho, E; Peresunko, D; Pérez Lara, C E; Perez Lezama, E; Perini, D; Perrino, D; Peryt, W; Pesci, A; Peskov, V; Pestov, Y; Petráček, V; Petran, M; Petris, M; Petrov, P; Petrovici, M; Petta, C; Piano, S; Piccotti, A; Pikna, M; Pillot, P; Pinazza, O; Pinsky, L; Pitz, N; Piyarathna, D B; Płoskoń, M; Pluta, J; Pocheptsov, T; Pochybova, S; Podesta-Lerma, P L M; Poghosyan, M G; Polák, K; Polichtchouk, B; Pop, A; Porteboeuf-Houssais, S; Pospíšil, V; Potukuchi, B; Prasad, S K; Preghenella, R; Prino, F; Pruneau, C A; Pshenichnov, I; Puchagin, S; Puddu, G; Pujol Teixido, J; Pulvirenti, A; Punin, V; Putiš, M; Putschke, J; Quercigh, E; Qvigstad, H; Rachevski, A; Rademakers, A; Radomski, S; Räihä, T S; Rak, J; Rakotozafindrabe, A; Ramello, L; Ramírez Reyes, A; Raniwala, S; Raniwala, R; Räsänen, S S; Rascanu, B T; Rathee, D; Read, K F; Real, J S; Redlich, K; Reichelt, P; Reicher, M; Renfordt, R; Reolon, A R; Reshetin, A; Rettig, F; Revol, J-P; Reygers, K; Riccati, L; Ricci, R A; Richert, T; Richter, M; Riedler, P; Riegler, W; Riggi, F; Rodrigues Fernandes Rabacal, B; Rodríguez Cahuantzi, M; Rodriguez Manso, A; Røed, K; Rohr, D; Röhrich, D; Romita, R; Ronchetti, F; Rosnet, P; Rossegger, S; Rossi, A; Roy, C; Roy, P; Rubio Montero, A J; Rui, R; Ryabinkin, E; Rybicki, A; Sadovsky, S; Šafařík, K; Sahoo, R; Sahu, P K; Saini, J; Sakaguchi, H; Sakai, S; Sakata, D; Salgado, C A; Salzwedel, J; Sambyal, S; Samsonov, V; Sanchez Castro, X; Šándor, L; Sandoval, A; Sano, S; Sano, M; Santo, R; Santoro, R; Sarkamo, J; Scapparone, E; Scarlassara, F; Scharenberg, R P; Schiaua, C; Schicker, R; Schmidt, C; Schmidt, H R; Schreiner, S; Schuchmann, S; Schukraft, J; Schutz, Y; Schwarz, K; Schweda, K; Scioli, G; Scomparin, E; Scott, R; Scott, P A; Segato, G; Selyuzhenkov, I; Senyukov, S; Seo, J; Serci, S; Serradilla, E; Sevcenco, A; Shabetai, A; Shabratova, G; Shahoyan, R; Sharma, N; Sharma, S; Rohni, S; Shigaki, K; Shimomura, M; Shtejer, K; Sibiriak, Y; Siciliano, M; Sicking, E; Siddhanta, S; Siemiarczuk, T; Silvermyr, D; Silvestre, C; Simatovic, G; Simonetti, G; Singaraju, R; Singh, R; Singha, S; Singhal, V; Sinha, T; Sinha, B C; Sitar, B; Sitta, M; Skaali, T B; Skjerdal, K; Smakal, R; Smirnov, N; Snellings, R J M; Søgaard, C; Soltz, R; Son, H; Song, M; Song, J; Soos, C; Soramel, F; Sputowska, I; Spyropoulou-Stassinaki, M; Srivastava, B K; Stachel, J; Stan, I; Stan, I; Stefanek, G; Steinbeck, T; Steinpreis, M; Stenlund, E; Steyn, G; Stiller, J H; Stocco, D; Stolpovskiy, M; Strabykin, K; Strmen, P; Suaide, A A P; Subieta Vásquez, M A; Sugitate, T; Suire, C; Sukhorukov, M; Sultanov, R; Šumbera, M; Susa, T; Szanto de Toledo, A; Szarka, I; Szczepankiewicz, A; Szostak, A; Szymanski, M; Takahashi, J; Tapia Takaki, J D; Tauro, A; Tejeda Muñoz, G; Telesca, A; Terrevoli, C; Thäder, J; Thomas, D; Tieulent, R; Timmins, A R; Tlusty, D; Toia, A; Torii, H; Toscano, L; Truesdale, D; Trzaska, W H; Tsuji, T; Tumkin, A; Turrisi, R; Tveter, T S; Ulery, J; Ullaland, K; Ulrich, J; Uras, A; Urbán, J; Urciuoli, G M; Usai, G L; Vajzer, M; Vala, M; Valencia Palomo, L; Vallero, S; van der Kolk, N; Vande Vyvre, P; van Leeuwen, M; Vannucci, L; Vargas, A; Varma, R; Vasileiou, M; Vasiliev, A; Vechernin, V; Veldhoen, M; Venaruzzo, M; Vercellin, E; Vergara, S; Vernet, R; Verweij, M; Vickovic, L; Viesti, G; Vikhlyantsev, O; Vilakazi, Z; Villalobos Baillie, O; Vinogradov, A; Vinogradov, L; Vinogradov, Y; Virgili, T; Viyogi, Y P; Vodopyanov, A; Voloshin, K; Voloshin, S; Volpe, G; von Haller, B; Vranic, D; Øvrebekk, G; Vrláková, J; Vulpescu, B; Vyushin, A; Wagner, V; Wagner, B; Wan, R; Wang, M; Wang, D; Wang, Y; Wang, Y; Watanabe, K; Weber, M; Wessels, J P; Westerhoff, U; Wiechula, J; Wikne, J; Wilde, M; Wilk, G; Wilk, A; Williams, M C S; Windelband, B; Xaplanteris Karampatsos, L; Yaldo, C G; Yamaguchi, Y; Yang, H; Yang, S; Yasnopolskiy, S; Yi, J; Yin, Z; Yoo, I-K; Yoon, J; Yu, W; Yuan, X; Yushmanov, I; Zach, C; Zampolli, C; Zaporozhets, S; Zarochentsev, A; Závada, P; Zaviyalov, N; Zbroszczyk, H; Zelnicek, P; Zgura, I S; Zhalov, M; Zhang, X; Zhang, H; Zhou, F; Zhou, D; Zhou, Y; Zhu, J; Zhu, J; Zhu, X; Zichichi, A; Zimmermann, A; Zinovjev, G; Zoccarato, Y; Zynovyev, M; Zyzak, M

2013-04-12

We report the first measurement of the net-charge fluctuations in Pb-Pb collisions at sqrt[sNN]=2.76  TeV, measured with the ALICE detector at the CERN Large Hadron Collider. The dynamical fluctuations per unit entropy are observed to decrease when going from peripheral to central collisions. An additional reduction in the amount of fluctuations is seen in comparison to the results from lower energies. We examine the dependence of fluctuations on the pseudorapidity interval, which may account for the dilution of fluctuations during the evolution of the system. We find that the fluctuations at the LHC are smaller compared to the measurements at the BNL Relativistic Heavy Ion Collider, and as such, closer to what has been theoretically predicted for the formation of a quark-gluon plasma.

The LHC magnet system and its status of development

NASA Technical Reports Server (NTRS)

Bona, Maurizio; Perin, Romeo; Vlogaert, Jos

1995-01-01

CERN is preparing for the construction of a new high energy accelerator/collider, the Large Hadron Collider (LHC). This new facility will mainly consist of two superconducting magnetic beam channels, 27 km long, to be installed in the existing LEP tunnel. The magnetic system comprises about 1200 twin-aperture dipoles, 13.145 m long, with an operational field of 8.65 T, about 600 quadrupoles, 3 m long, and a very large number of other superconducting magnetic components. A general description of the system is given together with the main features of the design of the regular lattice magnets. The paper also describes the present state of the magnet R & D program. Results from short model work, as well as from full scale prototypes will be presented, including the recently tested 10 m long full-scale prototype dipole manufactured in industry.

Polarized γ source based on Compton backscattering in a laser cavity

NASA Astrophysics Data System (ADS)

Yakimenko, V.; Pogorelsky, I. V.

2006-09-01

We propose a novel gamma source suitable for generating a polarized positron beam for the next generation of electron-positron colliders, such as the International Linear Collider (ILC), and the Compact Linear Collider (CLIC). This 30-MeV polarized gamma source is based on Compton scattering inside a picosecond CO2 laser cavity generated from electron bunches produced by a 4-GeV linac. We identified and experimentally verified the optimum conditions for obtaining at least one gamma photon per electron. After multiplication at several consecutive interaction points, the circularly polarized gamma rays are stopped on a target, thereby creating copious numbers of polarized positrons. We address the practicality of having an intracavity Compton-polarized positron source as the injector for these new colliders.

Physics with CMS and Electronic Upgrades

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rohlf, James W.

2016-08-01

The current funding is for continued work on the Compact Muon Solenoid (CMS) at the CERN Large Hadron Collider (LHC) as part of the Energy Frontier experimental program. The current budget year covers the first year of physics running at 13 TeV (Run 2). During this period we have concentrated on commisioning of the μTCA electronics, a new standard for distribution of CMS trigger and timing control signals and high bandwidth data aquistiion as well as participating in Run 2 physics.

UNIVERSITY OF ARIZONA HIGH ENERGY PHYSICS PROGRAM

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rutherfoord, John P.; Johns, Kenneth A.; Shupe, Michael A.

2013-07-29

The High Energy Physics Group at the University of Arizona has conducted forefront research in elementary particle physics. Our theorists have developed new ideas in lattice QCD, SUSY phenomenology, string theory phenomenology, extra spatial dimensions, dark matter, and neutrino astrophysics. The experimentalists produced significant physics results on the ATLAS experiment at CERN's Large Hadron Collider and on the D0 experiment at the Fermilab Tevatron. In addition, the experimentalists were leaders in detector development and construction, and on service roles in these experiments.

Deflected mirage mediation: a phenomenological framework for generalized supersymmetry breaking.

PubMed

Everett, Lisa L; Kim, Ian-Woo; Ouyang, Peter; Zurek, Kathryn M

2008-09-05

We present a general phenomenological framework for dialing between gravity mediation, gauge mediation, and anomaly mediation. The approach is motivated from recent developments in moduli stabilization, which suggest that gravity mediated terms can be effectively loop suppressed and thus comparable to gauge and anomaly mediated terms. The gauginos exhibit a mirage unification behavior at a "deflected" scale, and gluinos are often the lightest colored sparticles. The approach provides a rich setting in which to explore generalized supersymmetry breaking at the CERN Large Hadron Collider.

Full steam ahead

NASA Astrophysics Data System (ADS)

Heuer, Rolf-Dieter

2008-03-01

When the Economist recently reported the news of Rolf-Dieter Heuer's appointment as the next directorgeneral of CERN, it depicted him sitting cross-legged in the middle of a circular track steering a model train around him - smiling. It was an apt cartoon for someone who is about to take charge of the world's most powerful particle accelerator: the 27 km-circumference Large Hadron Collider (LHC), which is nearing completion at the European laboratory just outside Geneva. What the cartoonist did not known is that model railways are one of Heuer's passions.

Cosmic ray composition between 10 to the 15th power - 10 to the 17th power eV obtained by air shower experiments

NASA Technical Reports Server (NTRS)

Muraki, Y.

1985-01-01

Based on the air shower data, the chemical composition of the primary cosmic rays in the energy range 10 to the 15th power - 10 to the 17th power eV was obtained. The method is based on a well known N sub e-N sub mu and N sub e-N sub gamma. The simulation is calibrated by the CERN SPS pp collider results.

Hydrodynamic predictions for 5.44 TeV Xe+Xe collisions

NASA Astrophysics Data System (ADS)

Giacalone, Giuliano; Noronha-Hostler, Jacquelyn; Luzum, Matthew; Ollitrault, Jean-Yves

2018-03-01

We argue that relativistic hydrodynamics is able to make robust predictions for soft particle production in Xe+Xe collisions at the CERN Large Hadron Collider (LHC). The change of system size from Pb+Pb to Xe+Xe provides a unique opportunity to test the scaling laws inherent to fluid dynamics. Using event-by-event hydrodynamic simulations, we make quantitative predictions for several observables: mean transverse momentum, anisotropic flow coefficients, and their fluctuations. Results are shown as a function of collision centrality.

RICH upgrade in LHCb experiment

NASA Astrophysics Data System (ADS)

Pistone, A.; LHCb RICH Collaboration

2017-01-01

The LHCb experiment is dedicated to precision measurements of CP violation and rare decays of B hadrons at the Large Hadron Collider (LHC) at CERN (Geneva). The second long shutdown of the LHC is currently scheduled to begin in 2019. During this period the LHCb experiment with all its sub-detectors will be upgraded in order to run at an instantaneous luminosity of 2 × 10^{33} cm ^{-2} s ^{-1} , about a factor 5 higher than the current luminosity, and to read out data at a rate of 40MHz into a flexible software-based trigger. The Ring Imaging CHerenkov (RICH) system will require new photon detectors and modifications to the optics of the upstream detector. Tests of the prototype of the smallest constituent of the new RICH system have been performed during testbeam sessions at the North Area test beam facility at CERN in the last years.

Web Based Monitoring in the CMS Experiment at CERN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Badgett, William; Borrello, Laura; Chakaberia, Irakli

2014-09-03

The Compact Muon Solenoid (CMS) is a large and complex general purpose experiment at the CERN Large Hadron Collider (LHC), built and maintained by many collaborators from around the world. Efficient operation of the detector requires widespread and timely access to a broad range of monitoring and status information. To this end the Web Based Monitoring (WBM) system was developed to present data to users located anywhere from many underlying heterogeneous sources, from real time messaging systems to relational databases. This system provides the power to combine and correlate data in both graphical and tabular formats of interest to themore » experimenters, including data such as beam conditions, luminosity, trigger rates, detector conditions, and many others, allowing for flexibility on the user side. This paper describes the WBM system architecture and describes how the system was used during the first major data taking run of the LHC.« less

High energy beam impact tests on a LHC tertiary collimator at the CERN high-radiation to materials facility

NASA Astrophysics Data System (ADS)

Cauchi, Marija; Aberle, O.; Assmann, R. W.; Bertarelli, A.; Carra, F.; Cornelis, K.; Dallocchio, A.; Deboy, D.; Lari, L.; Redaelli, S.; Rossi, A.; Salvachua, B.; Mollicone, P.; Sammut, N.

2014-02-01

The correct functioning of a collimation system is crucial to safely operate highly energetic particle accelerators, such as the Large Hadron Collider (LHC). The requirements to handle high intensity beams can be demanding. In this respect, investigating the consequences of LHC particle beams hitting tertiary collimators (TCTs) in the experimental regions is a fundamental issue for machine protection. An experimental test was designed to investigate the robustness and effects of beam accidents on a fully assembled collimator, based on accident scenarios in the LHC. This experiment, carried out at the CERN High-Radiation to Materials (HiRadMat) facility, involved 440 GeV proton beam impacts of different intensities on the jaws of a horizontal TCT. This paper presents the experimental setup and the preliminary results obtained, together with some first outcomes from visual inspection and a comparison of such results with numerical simulations.

Design of a High Luminosity 100 TeV Proton-Antiproton Collider

NASA Astrophysics Data System (ADS)

Oliveros Tautiva, Sandra Jimena

Currently new physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. A 10 34 cm-2 s-1 luminosity 100 TeV proton-antiproton collider is explored with 7x the energy of the LHC. The dipoles are 4.5 T to reduce cost. A proton-antiproton collider is selected as a future machine for several reasons. The cross section for many high mass states is 10 times higher in pp than pp collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the number of events per bunch crossing, because lower beam currents can produce the same rare event rates. Events are also more centrally produced, allowing a more compact detector with less space between quadrupole triplets and a smaller beta* for higher luminosity. To adjust to antiproton beam losses (burn rate), a Fermilab-like antiproton source would be adapted to disperse the beam into 12 different momentum channels, using electrostatic septa, to increase antiproton momentum capture 12 times. At Fermilab, antiprotons were stochastically cooled in one Debuncher and one Accumulator ring. Because the stochastic cooling time scales as the number of particles, two options of 12 independent cooling systems are presented. One electron cooling ring might follow the stochastic cooling rings for antiproton stacking. Finally antiprotons in the collider ring would be recycled during runs without leaving the collider ring, by joining them to new bunches with snap bunch coalescence and synchrotron damping. These basic ideas are explored in this work on a future 100 TeV proton-antiproton collider and the main parameters are presented.

Design of a High Luminosity 100 TeV Proton Antiproton Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oliveros Tuativa, Sandra Jimena

2017-04-01

Currently new physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. A 10more » $$^{\\,34}$$ cm$$^{-2}$$ s$$^{-1}$$ luminosity 100 TeV proton-antiproton collider is explored with 7$$\\times$$ the energy of the LHC. The dipoles are 4.5\\,T to reduce cost. A proton-antiproton collider is selected as a future machine for several reasons. The cross section for many high mass states is 10 times higher in $$p\\bar{p}$$ than $pp$ collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the number of events per bunch crossing, because lower beam currents can produce the same rare event rates. Events are also more centrally produced, allowing a more compact detector with less space between quadrupole triplets and a smaller $$\\beta^{*}$$ for higher luminosity. To adjust to antiproton beam losses (burn rate), a Fermilab-like antiproton source would be adapted to disperse the beam into 12 different momentum channels, using electrostatic septa, to increase antiproton momentum capture 12 times. At Fermilab, antiprotons were stochastically cooled in one Debuncher and one Accumulator ring. Because the stochastic cooling time scales as the number of particles, two options of 12 independent cooling systems are presented. One electron cooling ring might follow the stochastic cooling rings for antiproton stacking. Finally antiprotons in the collider ring would be recycled during runs without leaving the collider ring, by joining them to new bunches with snap bunch coalescence and synchrotron damping. These basic ideas are explored in this work on a future 100 TeV proton-antiproton collider and the main parameters are presented.« less

R&D of a High-Performance DIRC Detector for a Future Electron-Ion Collider

NASA Astrophysics Data System (ADS)

Allison, Stacey Lee

An Electron-Ion Collider (EIC) is proposed as the next big scientific facility to be built in the United States, costing over $1 billion in design and construction. Each detector concept for the electron/ion beam interaction point is integrated into a large solenoidal magnet. The necessity for excellent hadronic particle identification (pion/kaon/proton) in the barrel region of the solenoid has pushed research and development (R&D) towards a new, high-performance Detection of Internally Reflected Cherenkov light (DIRC) detector design. The passage of a high energy charged particle through a fused silica bar of the DIRC generates optical Cherenkov radiation. A large fraction of this light propagates by total internal reflection to the end of the bar, where the photon trajectories expand in a large volume before reaching a highly segmented photo-detector array. The spatial and temporal distribution of the Cherenkov light at the photo-detector array allows one to reconstruct the angle of emission of the light relative to the incident charged particle track. In order to reach the desired performance of 3sigma pi/K separation at 6 GeV/c particle momentum a new 3-layer spherical lens focusing optic with a lanthanum crown glass central layer was designed to have a nearly flat focal plane. In order to validate the EIC DIRC simulation package, a synergistic test beam campaign was carried out in 2015 at the CERN PS with the PANDA Barrel DIRC group using a prototype DIRC detector. Along with the analysis of the CERN test beam data, measurements of the focal plane of the 3-layer lens were performed using a custom-built laser setup at Old Dominion University. Radiation hardness of the lanthanum crown glass was tested using a 160 keV X-ray source and a monochromator at the Catholic University of America. Results of these test-bench experiments and the analysis of the 2015 CERN test beam data are presented here.

R&D of a high-performance DIRC detector for a future electron-ion collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allison, Staceu L.

An Electron-Ion Collider (EIC) is proposed as the next big scientific facility to be built in the United States, costing over $1 billion in design and construction. Each detector concept for the electron/ion beam interaction point is integrated into a large solenoidal magnet. The necessity for excellent hadronic particle identification (pion/kaon/proton) in the barrel region of the solenoid has pushed research and development (R&D) towards a new, high-performance Detection of Internally Reflected Cherenkov light (DIRC) detector design. The passage of a high energy charged particle through a fused silica bar of the DIRC generates optical Cherenkov radiation. A large fractionmore » of this light propagates by total internal reflection to the end of the bar, where the photon trajectories expand in a large volume before reaching a highly segmented photo-detector array. The spatial and temporal distribution of the Cherenkov light at the photo-detector array allows one to reconstruct the angle of emission of the light relative to the incident charged particle track. In order to reach the desired performance of 3sigma pi/K separation at 6 GeV/c particle momentum a new 3-layer spherical lens focusing optic with a lanthanum crown glass central layer was designed to have a nearly at focal plane. In order to validate the EIC DIRC simulation package, a synergistic test beam campaign was carried out in 2015 at the CERN PS with the PANDA Barrel DIRC group using a prototype DIRC detector. Along with the analysis of the CERN test beam data, measurements of the focal plane of the 3-layer lens were performed using a custom-built laser setup at Old Dominion University. Radiation hardness of the lanthanum crown glass was tested using a 160 keV X-ray source and a monochromator at the Catholic University of America. Results of these test-bench experiments and the analysis of the 2015 CERN test beam data are presented here.« less

Commissioning results of CERN HIE-ISOLDE and INFN ALPI cryogenic control systems

NASA Astrophysics Data System (ADS)

Inglese, V.; Pezzetti, M.; Calore, A.; Modanese, P.; Pengo, R.

2017-02-01

The cryogenic systems of both accelerators, namely HIE ISOLDE (High Intensity and Energy Isotope Separator On Line DEvice) at CERN and ALPI (Acceleratore Lineare Per Ioni) at LNL, have been refurbished. HIE ISOLDE is a major upgrade of the existing ISOLDE facilities, which required the construction of a superconducting linear accelerator consisting of six cryomodules, each containing five superconductive RF cavities and superconducting solenoids. The ALPI linear accelerator, similar to HIE ISOLDE, is located at Legnaro National Laboratories (LNL) and became operational in the early 90’s. It is composed of 74 superconducting RF cavities, assembled inside 22 cryostats. The new control systems are equipped with PLC, developed on the CERN UNICOS framework, which include Schneider and Siemens PLCs and various fieldbuses (Profibus DP and PA, WorldFIP). The control systems were developed in synergy between CERN and LNL in order to build, effectively and with an optimized use of resources, control systems allowing to enhance ease of operation, maintainability, and long-term availability. This paper describes (i) the cryogenic systems, with special focus on the design of the control systems hardware and software, (ii) the strategy adopted in order to achieve a synergic approach, and (iii) the commissioning results after the cool-down to 4.5 K of the cryomodules.

Design and performance of the virtualization platform for offline computing on the ATLAS TDAQ Farm

NASA Astrophysics Data System (ADS)

Ballestrero, S.; Batraneanu, S. M.; Brasolin, F.; Contescu, C.; Di Girolamo, A.; Lee, C. J.; Pozo Astigarraga, M. E.; Scannicchio, D. A.; Twomey, M. S.; Zaytsev, A.

2014-06-01

With the LHC collider at CERN currently going through the period of Long Shutdown 1 there is an opportunity to use the computing resources of the experiments' large trigger farms for other data processing activities. In the case of the ATLAS experiment, the TDAQ farm, consisting of more than 1500 compute nodes, is suitable for running Monte Carlo (MC) production jobs that are mostly CPU and not I/O bound. This contribution gives a thorough review of the design and deployment of a virtualized platform running on this computing resource and of its use to run large groups of CernVM based virtual machines operating as a single CERN-P1 WLCG site. This platform has been designed to guarantee the security and the usability of the ATLAS private network, and to minimize interference with TDAQ's usage of the farm. Openstack has been chosen to provide a cloud management layer. The experience gained in the last 3.5 months shows that the use of the TDAQ farm for the MC simulation contributes to the ATLAS data processing at the level of a large Tier-1 WLCG site, despite the opportunistic nature of the underlying computing resources being used.

Compensation of the long-range beam-beam interactions as a path towards new configurations for the high luminosity LHC

DOE PAGES

Fartoukh, Stéphane; Valishev, Alexander; Papaphilippou, Yannis; ...

2015-12-01

Colliding bunch trains in a circular collider demands a certain crossing angle in order to separate the two beams transversely after the collision. The magnitude of this crossing angle is a complicated function of the bunch charge, the number of long-range beam-beam interactions, of β* and type of optics (flat or round), and possible compensation or additive effects between several low-β insertions in the ring depending on the orientation of the crossing plane at each interaction point. About 15 years ago, the use of current bearing wires was proposed at CERN in order to mitigate the long-range beam-beam effects [J.P. Koutchouk,more » CERN Report No. LHC-Project-Note 223, 2000], therefore offering the possibility to minimize the crossing angle with all the beneficial effects this might have: on the luminosity performance by reducing the need for crab-cavities or lowering their voltage, on the required aperture of the final focus magnets, on the strength of the orbit corrector involved in the crossing bumps, and finally on the heat load and radiation dose deposited in the final focus quadrupoles. In this paper, a semianalytical approach is developed for the compensation of the long-range beam-beam interactions with current wires. This reveals the possibility of achieving optimal correction through a careful adjustment of the aspect ratio of the β functions at the wire position. We consider the baseline luminosity upgrade plan of the Large Hadron Collider (HL-LHC project), and compare it to alternative scenarios, or so-called ''configurations,'' where modifications are applied to optics, crossing angle, or orientation of the crossing plane in the two low-β insertions of the ring. Furthermore, for all these configurations, the beneficial impact of beam-beam compensation devices is then demonstrated on the tune footprint, the dynamical aperture, and/or the frequency map analysis of the nonlinear beam dynamics as the main figures of merit.« less

Double elementary Goldstone Higgs boson production in future linear colliders

NASA Astrophysics Data System (ADS)

Guo, Yu-Chen; Yue, Chong-Xing; Liu, Zhi-Cheng

2018-03-01

The Elementary Goldstone Higgs (EGH) model is a perturbative extension of the Standard Model (SM), which identifies the EGH boson as the observed Higgs boson. In this paper, we study pair production of the EGH boson in future linear electron positron colliders. The cross-sections in the TeV region can be changed to about ‑27%, 163% and ‑34% for the e+e‑→ Zhh, e+e‑→ νν¯hh and e+e‑→ tt¯hh processes with respect to the SM predictions, respectively. According to the expected measurement precisions, such correction effects might be observed in future linear colliders. In addition, we compare the cross-sections of double SM-like Higgs boson production with the predictions in other new physics models.

Analysis of b quark pair production signal from neutral 2HDM Higgs bosons at future linear colliders

NASA Astrophysics Data System (ADS)

Hashemi, Majid; MahdaviKhorrami, Mostafa

2018-06-01

In this paper, the b quark pair production events are analyzed as a source of neutral Higgs bosons of the two Higgs doublet model type I at linear colliders. The production mechanism is e+e- → Z^{(*)} → HA → b{\\bar{b}}b{\\bar{b}} assuming a fully hadronic final state. The analysis aim is to identify both CP-even and CP-odd Higgs bosons in different benchmark points accommodating moderate boson masses. Due to pair production of Higgs bosons, the analysis is most suitable for a linear collider operating at √{s} = 1 TeV. Results show that in selected benchmark points, signal peaks are observable in the b-jet pair invariant mass distributions at integrated luminosity of 500 fb^{-1}.

Elementary Particle Physics and High Energy Phenomena: Final Report for FY2010-13

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cumalat, John P.; de Alwis, Senarath P.; DeGrand, Thomas A.

2013-06-27

The work under this grant consists of experimental, theoretical, and phenomenological research on the fundamental properties of high energy subnuclear particles. The work is conducted at the University of Colorado, the European Organization for Nuclear Research (CERN), the Japan Proton Accelerator Research Complex (J-PARC), Fermi National Accelerator Laboratory (FNAL), SLAC National Accelerator Laboratory (SLAC), Los Alamos National Laboratory (LANL), and other facilities, employing neutrino-beam experiments, test beams of various particles, and proton-proton collider experiments. It emphasizes mass generation and symmetry-breaking, neutrino oscillations, bottom particle production and decay, detector development, supergravity, supersymmetry, superstrings, quantum chromodynamics, nonequilibrium statistical mechanics, cosmology, phase transitions,more » lattice gauge theory, and anomaly-free theories. The goals are to improve our understanding of the basic building blocks of matter and their interactions. Data from the Large Hadron Collider at CERN have revealed new interactions responsible for particle mass, and perhaps will lead to a more unified picture of the forces among elementary material constituents. To this end our research includes searches for manifestations of theories such as supersymmetry and new gauge bosons, as well as the production and decay of heavy-flavored quarks. Our current work at J-PARC, and future work at new facilities currently under conceptual design, investigate the specifics of how the neutrinos change flavor. The research is integrated with the training of students at all university levels, benefiting both the manpower and intellectual base for future technologies.« less

Drell-Yan production of multi Z '-bosons at the LHC within Non-Universal ED and 4D Composite Higgs Models

NASA Astrophysics Data System (ADS)

Accomando, Elena; Barducci, Daniele; De Curtis, Stefania; Fiaschi, Juri; Moretti, Stefano; Shepherd-Themistocleous, C. H.

2016-07-01

The Drell-Yan di-lepton production at hadron colliders is by far the preferred channel to search for new heavy spin-1 particles. Traditionally, such searches have exploited the Narrow Width Approximation (NWA) for the signal, thereby neglecting the effect of the interference between the additional Z '-bosons and the Standard Model Z and γ. Recently, it has been established that both finite width and interference effects can be dealt with in experimental searches while still retaining the model independent approach ensured by the NWA. This assessment has been made for the case of popular single Z '-boson models currently probed at the CERN Large Hadron Collider (LHC). In this paper, we test the scope of the CERN machine in relation to the above issues for some benchmark multi Z '-boson models. In particular, we consider Non-Universal Extra Dimensional (NUED) scenarios and the 4-Dimensional Composite Higgs Model (4DCHM), both predicting a multi- Z ' peaking structure. We conclude that in a variety of cases, specifically those in which the leptonic decays modes of one or more of the heavy neutral gauge bosons are suppressed and/or significant interference effects exist between these or with the background, especially present when their decay widths are significant, traditional search approaches based on the assumption of rather narrow and isolated objects might require suitable modifications to extract the underlying dynamics.

Predictions for multiplicities and flow harmonics in 5.44 TeV Xe+Xe collisions at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Eskola, K. J.; Niemi, H.; Paatelainen, R.; Tuominen, K.

2018-03-01

We present the event-by-event next-to-leading-order perturbative-QCD + saturation + viscous hydrodynamics (EKRT) model predictions for the centrality dependence of the charged hadron multiplicity in the pseudorapidity interval |η |≤0.5 , and for the centrality dependence of the charged hadron flow harmonics vn{2 } obtained from two-particle cumulants, in √{sN N}=5.44 TeV Xe+Xe collisions at the CERN Large Hadron Collider. Our prediction for the 0-5 % central charged multiplicity is d Nch/d η =1218 ±46 . We also predict vn{2 } in Xe+Xe collisions to increase more slowly from central towards peripheral collisions than those in a Pb+Pb system. We find that at 10 ,⋯,50 % centralities v2{2 } is smaller and v3{2 } is larger than in the Pb+Pb system while v4{2 } is of the same magnitude in both systems. We also find that the ratio of flow harmonics in Xe+Xe collisions and in Pb+Pb collisions shows a slight sensitivity to the temperature dependence of the shear-viscosity-to-entropy ratio. As we discuss here, the new nuclear mass-number systematics especially in the flow harmonics serves as a welcome further constraint for describing the space-time evolution of a heavy-ion system and for determining the shear viscosity and other transport properties of strongly interacting matter.

First Operational Experience With a High-Energy Physics Run Control System Based on Web Technologies

NASA Astrophysics Data System (ADS)

Bauer, Gerry; Beccati, Barbara; Behrens, Ulf; Biery, Kurt; Branson, James; Bukowiec, Sebastian; Cano, Eric; Cheung, Harry; Ciganek, Marek; Cittolin, Sergio; Coarasa Perez, Jose Antonio; Deldicque, Christian; Erhan, Samim; Gigi, Dominique; Glege, Frank; Gomez-Reino, Robert; Gulmini, Michele; Hatton, Derek; Hwong, Yi Ling; Loizides, Constantin; Ma, Frank; Masetti, Lorenzo; Meijers, Frans; Meschi, Emilio; Meyer, Andreas; Mommsen, Remigius K.; Moser, Roland; O'Dell, Vivian; Oh, Alexander; Orsini, Luciano; Paus, Christoph; Petrucci, Andrea; Pieri, Marco; Racz, Attila; Raginel, Olivier; Sakulin, Hannes; Sani, Matteo; Schieferdecker, Philipp; Schwick, Christoph; Shpakov, Dennis; Simon, Michal; Sumorok, Konstanty; Yoon, Andre Sungho

2012-08-01

Run control systems of modern high-energy particle physics experiments have requirements similar to those of today's Internet applications. The Compact Muon Solenoid (CMS) collaboration at CERN's Large Hadron Collider (LHC) therefore decided to build the run control system for its detector based on web technologies. The system is composed of Java Web Applications distributed over a set of Apache Tomcat servlet containers that connect to a database back-end. Users interact with the system through a web browser. The present paper reports on the successful scaling of the system from a small test setup to the production data acquisition system that comprises around 10.000 applications running on a cluster of about 1600 hosts. We report on operational aspects during the first phase of operation with colliding beams including performance, stability, integration with the CMS Detector Control System and tools to guide the operator.

Taus and the Trigger for Discovery at ATLAS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Demers, Sarah

This five year grant allowed Yale Professor Sarah Demers and her students and postdocs to contribute to the ATLAS Experiment at CERN's Large Hadron Collider. We worked on a particular mode of the Higgs Boson decay, contributing to the discovery of this particle as well as measuring the particle's properties. We also performed a "first of its kind" measurement at a hadron collider in the measurement of tau polarization, which increased the sensitivity of ATLAS in a number of exciting ways, both for making measurements of known particles and for hunting for new ones. We also contributed to the taumore » trigger - the real-time selection that chooses data that includes the signature of the tau lepton. Four PhD students in the Yale Physics Department received their PhDs during the term of this grant, with at least partial support from the grant.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Buchanan, Charles D.; Cline, David B.; Byers, N.

Progress in the various components of the UCLA High-Energy Physics Research program is summarized, including some representative figures and lists of resulting presentations and published papers. Principal efforts were directed at the following: (I) UCLA hadronization model, PEP4/9 e{sup +}e{sup {minus}} analysis, {bar P} decay; (II) ICARUS and astroparticle physics (physics goals, technical progress on electronics, data acquisition, and detector performance, long baseline neutrino beam from CERN to the Gran Sasso and ICARUS, future ICARUS program, and WIMP experiment with xenon), B physics with hadron beams and colliders, high-energy collider physics, and the {phi} factory project; (III) theoretical high-energy physics;more » (IV) H dibaryon search, search for K{sub L}{sup 0} {yields} {pi}{sup 0}{gamma}{gamma} and {pi}{sup 0}{nu}{bar {nu}}, and detector design and construction for the FNAL-KTeV project; (V) UCLA participation in the experiment CDF at Fermilab; and (VI) VLPC/scintillating fiber R D.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

Progress in the various components of the UCLA High-Energy Physics Research program is summarized, including some representative figures and lists of resulting presentations and published papers. Principal efforts were directed at the following: (I) UCLA hadronization model, PEP4/9 e{sup +}e{sup {minus}} analysis, {bar P} decay; (II) ICARUS and astroparticle physics (physics goals, technical progress on electronics, data acquisition, and detector performance, long baseline neutrino beam from CERN to the Gran Sasso and ICARUS, future ICARUS program, and WIMP experiment with xenon), B physics with hadron beams and colliders, high-energy collider physics, and the {phi} factory project; (III) theoretical high-energy physics;more » (IV) H dibaryon search, search for K{sub L}{sup 0} {yields} {pi}{sup 0}{gamma}{gamma} and {pi}{sup 0}{nu}{bar {nu}}, and detector design and construction for the FNAL-KTeV project; (V) UCLA participation in the experiment CDF at Fermilab; and (VI) VLPC/scintillating fiber R & D.« less

Electron cloud buildup driving spontaneous vertical instabilities of stored beams in the Large Hadron Collider

NASA Astrophysics Data System (ADS)

Romano, Annalisa; Boine-Frankenheim, Oliver; Buffat, Xavier; Iadarola, Giovanni; Rumolo, Giovanni

2018-06-01

At the beginning of the 2016 run, an anomalous beam instability was systematically observed at the CERN Large Hadron Collider (LHC). Its main characteristic was that it spontaneously appeared after beams had been stored for several hours in collision at 6.5 TeV to provide data for the experiments, despite large chromaticity values and high strength of the Landau-damping octupole magnet. The instability exhibited several features characteristic of those induced by the electron cloud (EC). Indeed, when LHC operates with 25 ns bunch spacing, an EC builds up in a large fraction of the beam chambers, as revealed by several independent indicators. Numerical simulations have been carried out in order to investigate the role of the EC in the observed instabilities. It has been found that the beam intensity decay is unfavorable for the beam stability when LHC operates in a strong EC regime.

Hadronic production of W and Z bosons at large transverse momentum

DOE Office of Scientific and Technical Information (OSTI.GOV)

Berger, Edmond L.; Gao, Jun; Kang, Zhong-Bo

2015-06-01

We introduce a modified factorization formalism in quantum chromodynamics for hadronic production of W and Z bosons at large transverse momentum p(T). When p(T) is much larger than the invariant mass Q of the vector boson, this new factorization formalism systematically resums the large fragmentation logarithms, alpha(m)(s)ln(m) (p(T)(2)/Q(2)), to all orders in the strong coupling alpha(s). Using our modified factorization formalism, we present the next-to-leading-order (NLO) predictions for W and Z boson production at high p(T) at the CERN Large Hadron Collider and at a future 100 TeV proton-proton collider. Our NLO results are about 5% larger in normalization, andmore » they show improved convergence and moderate reduction of the scale variation compared to the NLO predictions derived in a conventional fixed-order perturbative expansion.« less

Towards the conceptual design of the cryogenic system of the Future Circular Collider (FCC)

NASA Astrophysics Data System (ADS)

Chorowski, M.; Correia Rodrigues, H.; Delikaris, D.; Duda, P.; Haberstroh, C.; Holdener, F.; Klöppel, S.; Kotnig, C.; Millet, F.; Polinski, J.; Quack, H.; Tavian, L.

2017-12-01

Following the update of the European strategy in particle physics, CERN has undertaken an international study of possible future circular colliders beyond the LHC. The study considers several options for very high-energy hadron-hadron, electron-positron and hadron-electron colliders. From the cryogenics point of view, the most challenging option is the hadron-hadron collider (FCC-hh) for which the conceptual design of the cryogenic system is progressing. The FCC-hh cryogenic system will have to produce up to 120 kW at 1.8 K for the superconducting magnet cooling, 6 MW between 40 and 60 K for the beam-screen and thermal-shield cooling as well as 850 g/s between 40 and 290 K for the HTS current-lead cooling. The corresponding total entropic load represents about 1 MW equivalent at 4.5 K and this cryogenic system will be by far the largest ever designed. In addition, the total mass to be cooled down is about 250’000 t and an innovative cool-down process must be proposed. This paper will present the proposed cryogenic layout and architecture, the cooling principles of the main components, the corresponding cooling schemes, as well as the cryogenic plant arrangement and proposed process cycles. The corresponding required development plan for such challenging cryogenic system will be highlighted.

Got Questions About the Higgs Boson? Ask a Scientist

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hinchliffe, Ian

Ask a scientist about the Higgs boson. There's a lot of buzz this week over new data from CERN's Large Hadron Collider (LHC) and the final data from Fermilab's Tevatron about the Higgs boson. It raises questions about what scientists have found and what still remains to be found -- and what it all means. Berkeley Lab's Ian Hinchliffe invites you to send in questions about the Higgs. He'll answer a few of your questions in a follow-up video later this week. Hinchliffe is a theoretical physicist who heads Berkeley Lab's sizable contingent with the ATLAS experiment at CERN. •more » Post your questions in the comment box • E-mail your questions to askascientist@lbl.gov • Tweet to @BerkeleyLab • Or post on our facebook page: facebook/berkeleylab Update on July 5: Ian responds to several of your questions in this video: http://youtu.be/1BkpD1IS62g. Update on 7/04: Here's CERN's press release from earlier today on the latest preliminary results in the search for the long sought Higgs particle: http://press.web.cern.ch/press/PressReleases/Releases2012/PR17.12E.htm. And here's a Q&A on what the news tells us: http://cdsweb.cern.ch/journal/CERNBulletin/2012/28/News%20Articles/1459460?ln=en. CERN will present the new LHC data at a seminar July 4th at 9:00 in the morning Geneva time (3:00 in the morning Eastern Daylight Time, midnight on the Pacific Coast), where the ATLAS collaboration and their rivals in the CMS experiment will announce their results. Tevatron results were announced by Fermilab on Monday morning. For more background on the LHC's search for the Higgs boson, visit http://newscenter.lbl.gov/feature-stories/2012/06/28/higgs-2012/.« less

Got Questions About the Higgs Boson? Ask a Scientist

ScienceCinema

Hinchliffe, Ian

2017-12-12

Ask a scientist about the Higgs boson. There's a lot of buzz this week over new data from CERN's Large Hadron Collider (LHC) and the final data from Fermilab's Tevatron about the Higgs boson. It raises questions about what scientists have found and what still remains to be found -- and what it all means. Berkeley Lab's Ian Hinchliffe invites you to send in questions about the Higgs. He'll answer a few of your questions in a follow-up video later this week. Hinchliffe is a theoretical physicist who heads Berkeley Lab's sizable contingent with the ATLAS experiment at CERN. • Post your questions in the comment box • E-mail your questions to askascientist@lbl.gov • Tweet to @BerkeleyLab • Or post on our facebook page: facebook/berkeleylab Update on July 5: Ian responds to several of your questions in this video: http://youtu.be/1BkpD1IS62g. Update on 7/04: Here's CERN's press release from earlier today on the latest preliminary results in the search for the long sought Higgs particle: http://press.web.cern.ch/press/PressReleases/Releases2012/PR17.12E.htm. And here's a Q&A on what the news tells us: http://cdsweb.cern.ch/journal/CERNBulletin/2012/28/News%20Articles/1459460?ln=en. CERN will present the new LHC data at a seminar July 4th at 9:00 in the morning Geneva time (3:00 in the morning Eastern Daylight Time, midnight on the Pacific Coast), where the ATLAS collaboration and their rivals in the CMS experiment will announce their results. Tevatron results were announced by Fermilab on Monday morning. For more background on the LHC's search for the Higgs boson, visit http://newscenter.lbl.gov/feature-stories/2012/06/28/higgs-2012/.

Approaching the CDF Top Quark Mass Legacy Measurement in the Lepton+Jets channel with the Matrix Element Method

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tosciri, Cecilia

2016-01-01

The discovery of the bottom quark in 1977 at the Tevatron Collider triggered the search for its partner in the third fermion isospin doublet, the top quark, which was discovered 18 years later in 1995 by the CDF and D=0 experiments during the Tevatron Run I. By 1990, intensive efforts by many groups at several accelerators had lifted to over 90 GeV=c2 the lower mass limit, such that since then the Tevatron became the only accelerator with high-enough energy to possibly discover this amazingly massive quark. After its discovery, the determination of top quark properties has been one of themore » main goals of the Fermilab Tevatron Collider, and more recently also of the Large Hadron Collider (LHC) at CERN. Since the mass value plays an important role in a large number of theoretical calculations on fundamental processes, improving the accuracy of its measurement has been at any time a goal of utmost importance. The present thesis describes in detail the contributions given by the candidate to the massive preparation work needed to make the new analysis possible, during her 8 months long stay at Fermilab.« less

Future HEP Accelerators: The US Perspective

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhat, Pushpalatha; Shiltsev, Vladimir

2015-11-02

Accelerator technology has advanced tremendously since the introduction of accelerators in the 1930s, and particle accelerators have become indispensable instruments in high energy physics (HEP) research to probe Nature at smaller and smaller distances. At present, accelerator facilities can be classified into Energy Frontier colliders that enable direct discoveries and studies of high mass scale particles and Intensity Frontier accelerators for exploration of extremely rare processes, usually at relatively low energies. The near term strategies of the global energy frontier particle physics community are centered on fully exploiting the physics potential of the Large Hadron Collider (LHC) at CERN throughmore » its high-luminosity upgrade (HL-LHC), while the intensity frontier HEP research is focused on studies of neutrinos at the MW-scale beam power accelerator facilities, such as Fermilab Main Injector with the planned PIP-II SRF linac project. A number of next generation accelerator facilities have been proposed and are currently under consideration for the medium- and long-term future programs of accelerator-based HEP research. In this paper, we briefly review the post-LHC energy frontier options, both for lepton and hadron colliders in various regions of the world, as well as possible future intensity frontier accelerator facilities.« less

SLC: The End Game

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raimondi, Pantaleo

The design of the Stanford Linear Collider (SLC) called for a beam intensity far beyond what was practically achievable. This was due to intrinsic limitations in many subsystems and to a lack of understanding of the new physics of linear colliders. Real progress in improving the SLC performance came from precision, non-invasive diagnostics to measure and monitor the beams and from new techniques to control the emittance dilution and optimize the beams. A major contribution to the success of the last 1997-98 SLC run came from several innovative ideas for improving the performance of the Final Focus (FF). This papermore » describes some of the problems encountered and techniques used to overcome them. Building on the SLC experience, we will also present a new approach to the FF design for future high energy linear colliders.« less

Design and system integration of the superconducting wiggler magnets for the Compact Linear Collider damping rings

NASA Astrophysics Data System (ADS)

Schoerling, Daniel; Antoniou, Fanouria; Bernhard, Axel; Bragin, Alexey; Karppinen, Mikko; Maccaferri, Remo; Mezentsev, Nikolay; Papaphilippou, Yannis; Peiffer, Peter; Rossmanith, Robert; Rumolo, Giovanni; Russenschuck, Stephan; Vobly, Pavel; Zolotarev, Konstantin

2012-04-01

To achieve high luminosity at the collision point of the Compact Linear Collider (CLIC), the normalized horizontal and vertical emittances of the electron and positron beams must be reduced to 500 and 4 nm before the beams enter the 1.5 TeV linear accelerators. An effective way to accomplish ultralow emittances with only small effects on the electron polarization is using damping rings operating at 2.86 GeV equipped with superconducting wiggler magnets. This paper describes a technical design concept for the CLIC damping wigglers.

Signal Study of the Pair Production of Z’ Bosons Decaying to Dark Matter and Boosted Jets at CMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Silverio, Diana Leon; Jayatilaka, Bo; Cremonesi, Matteo

2017-01-01

This study aims to develop a search for Dark Matter (DM) in a signature of missing transverse energy and jets in the CMS detector at the Large Hadron Collider at CERN. We study the generation of a simplified model for the pair production of spin-1 Z’ bosons, with one of them decaying into a pair of DM particles. The signal events are generated via MadGraph, in the LHE (Les Houches Event) file format, and their kinematics are studied.

Exotic Higgs boson decay modes as a harbinger of S{sub 3} flavor symmetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bhattacharyya, Gautam; Leser, Philipp; Paes, Heinrich

2011-01-01

Discrete symmetries employed to explain flavor mixing and mass hierarchies can be associated with an enlarged scalar sector which might lead to exotic Higgs decay modes. In this paper, we explore such a possibility in a scenario with S{sub 3} flavor symmetry which requires three scalar SU(2) doublets. The spectrum is fixed by minimizing the scalar potential, and we observe that the symmetry of the model leads to tantalizing Higgs decay modes potentially observable at the CERN Large Hadron Collider.

First measurement of Bose-Einstein correlations in proton-proton collisions at √s=0.9 and 2.36 TeV at the LHC.

PubMed

Khachatryan, V; Sirunyan, A M; Tumasyan, A; Adam, W; Bergauer, T; Dragicevic, M; Erö, J; Fabjan, C; Friedl, M; Frühwirth, R; Ghete, V M; Hammer, J; Hänsel, S; Hoch, M; Hörmann, N; Hrubec, J; Jeitler, M; Kasieczka, G; Kiesenhofer, W; Krammer, M; Liko, D; Mikulec, I; Pernicka, M; Rohringer, H; Schöfbeck, R; Strauss, J; Taurok, A; Teischinger, F; Waltenberger, W; Walzel, G; Widl, E; Wulz, C-E; Mossolov, V; Shumeiko, N; Suarez Gonzalez, J; Benucci, L; Ceard, L; De Wolf, E A; Hashemi, M; Janssen, X; Maes, T; Mucibello, L; Ochesanu, S; Roland, B; Rougny, R; Selvaggi, M; Van Haevermaet, H; Van Mechelen, P; Van Remortel, N; Adler, V; Beauceron, S; Blyweert, S; D'Hondt, J; Devroede, O; Kalogeropoulos, A; Maes, J; Maes, M; Tavernier, S; Van Doninck, W; Van Mulders, P; Villella, I; Chabert, E C; Charaf, O; Clerbaux, B; De Lentdecker, G; Dero, V; Gay, A P R; Hammad, G H; Marage, P E; Vander Velde, C; Vanlaer, P; Wickens, J; Costantini, S; Grunewald, M; Klein, B; Marinov, A; Ryckbosch, D; Thyssen, F; Tytgat, M; Vanelderen, L; Verwilligen, P; Walsh, S; Zaganidis, N; Basegmez, S; Bruno, G; Caudron, J; De Favereau De Jeneret, J; Delaere, C; Demin, P; Favart, D; Giammanco, A; Grégoire, G; Hollar, J; Lemaitre, V; Militaru, O; Ovyn, S; Pagano, D; Pin, A; Piotrzkowski, K; Quertenmont, L; Schul, N; Beliy, N; Caebergs, T; Daubie, E; Alves, G A; Pol, M E; Souza, M H G; Carvalho, W; Da Costa, E M; De Jesus Damiao, D; De Oliveira Martins, C; Fonseca De Souza, S; Mundim, L; Oguri, V; Santoro, A; Silva Do Amaral, S M; Sznajder, A; Torres Da Silva De Araujo, F; Dias, F A; Dias, M A F; Fernandez Perez Tomei, T R; Gregores, E M; Marinho, F; Novaes, S F; Padula, Sandra S; Darmenov, N; Dimitrov, L; Genchev, V; Iaydjiev, P; Piperov, S; Stoykova, S; Sultanov, G; Trayanov, R; Vankov, I; Dyulendarova, M; Hadjiiska, R; Kozhuharov, V; Litov, L; Marinova, E; Mateev, M; Pavlov, B; Petkov, P; Bian, J G; Chen, G M; Chen, H S; Jiang, C H; Liang, D; Liang, S; Wang, J; Wang, J; Wang, X; Wang, Z; Yang, M; Zang, J; Zhang, Z; Ban, Y; Guo, S; Hu, Z; Mao, Y; Qian, S J; Teng, H; Zhu, B; Cabrera, A; Carrillo Montoya, C A; Gomez Moreno, B; Ocampo Rios, A A; Osorio Oliveros, A F; Sanabria, J C; Godinovic, N; Lelas, D; Lelas, K; Plestina, R; Polic, D; Puljak, I; Antunovic, Z; Dzelalija, M; Brigljevic, V; Duric, S; Kadija, K; Morovic, S; Attikis, A; Fereos, R; Galanti, M; Mousa, J; Nicolaou, C; Papadakis, A; Ptochos, F; Razis, P A; Rykaczewski, H; Tsiakkouri, D; Zinonos, Z; Mahmoud, M; Hektor, A; Kadastik, M; Kannike, K; Müntel, M; Raidal, M; Rebane, L; Azzolini, V; Eerola, P; Czellar, S; Härkönen, J; Heikkinen, A; Karimäki, V; Kinnunen, R; Klem, J; Kortelainen, M J; Lampén, T; Lassila-Perini, K; Lehti, S; Lindén, T; Luukka, P; Mäenpää, T; Tuominen, E; Tuominiemi, J; Tuovinen, E; Ungaro, D; Wendland, L; Banzuzi, K; Korpela, A; Tuuva, T; Sillou, D; Besancon, M; Dejardin, M; Denegri, D; Descamps, J; Fabbro, B; Faure, J L; Ferri, F; Ganjour, S; Gentit, F X; Givernaud, A; Gras, P; Hamel de Monchenault, G; Jarry, P; Locci, E; Malcles, J; Marionneau, M; Millischer, L; Rander, J; Rosowsky, A; Rousseau, D; Titov, M; Verrecchia, P; Baffioni, S; Bianchini, L; Bluj, M; Broutin, C; Busson, P; Charlot, C; Dobrzynski, L; Elgammal, S; Granier de Cassagnac, R; Haguenauer, M; Kalinowski, A; Miné, P; Paganini, P; Sabes, D; Sirois, Y; Thiebaux, C; Zabi, A; Agram, J-L; Besson, A; Bloch, D; Bodin, D; Brom, J-M; Cardaci, M; Conte, E; Drouhin, F; Ferro, C; Fontaine, J-C; Gelé, D; Goerlach, U; Greder, S; Juillot, P; Karim, M; Le Bihan, A-C; Mikami, Y; Speck, J; Van Hove, P; Fassi, F; Mercier, D; Baty, C; Beaupere, N; Bedjidian, M; Bondu, O; Boudoul, G; Boumediene, D; Brun, H; Chanon, N; Chierici, R; Contardo, D; Depasse, P; El Mamouni, H; Fay, J; Gascon, S; Ille, B; Kurca, T; Le Grand, T; Lethuillier, M; Mirabito, L; Perries, S; Sordini, V; Tosi, S; Tschudi, Y; Verdier, P; Xiao, H; Roinishvili, V; Anagnostou, G; Edelhoff, M; Feld, L; Heracleous, N; Hindrichs, O; Jussen, R; Klein, K; Merz, J; Mohr, N; Ostapchuk, A; Perieanu, A; Raupach, F; Sammet, J; Schael, S; Sprenger, D; Weber, H; Weber, M; Wittmer, B; Actis, O; Ata, M; Bender, W; Biallass, P; Erdmann, M; Frangenheim, J; Hebbeker, T; Hinzmann, A; Hoepfner, K; Hof, C; Kirsch, M; Klimkovich, T; Kreuzer, P; Lanske, D; Magass, C; Merschmeyer, M; Meyer, A; Papacz, P; Pieta, H; Reithler, H; Schmitz, S A; Sonnenschein, L; Sowa, M; Steggemann, J; Teyssier, D; Zeidler, C; Bontenackels, M; Davids, M; Duda, M; Flügge, G; Geenen, H; Giffels, M; Haj Ahmad, W; Heydhausen, D; Kress, T; Kuessel, Y; Linn, A; Nowack, A; Perchalla, L; Pooth, O; Sauerland, P; Stahl, A; Thomas, M; Tornier, D; Zoeller, M H; Aldaya Martin, M; Behrenhoff, W; Behrens, U; Bergholz, M; Borras, K; Campbell, A; Castro, E; Dammann, D; Eckerlin, G; Flossdorf, A; Flucke, G; Geiser, A; Hauk, J; Jung, H; Kasemann, M; Katkov, I; Kleinwort, C; Kluge, H; Knutsson, A; Kuznetsova, E; Lange, W; Lohmann, W; Mankel, R; Marienfeld, M; Melzer-Pellmann, I-A; Meyer, A B; Mnich, J; Mussgiller, A; Olzem, J; Parenti, A; Raspereza, A; Schmidt, R; Schoerner-Sadenius, T; Sen, N; Stein, M; Tomaszewska, J; Volyanskyy, D; Wissing, C; Autermann, C; Draeger, J; Eckstein, D; Enderle, H; Gebbert, U; Kaschube, K; Kaussen, G; Klanner, R; Mura, B; Naumann-Emme, S; Nowak, F; Sander, C; Schettler, H; Schleper, P; Schröder, M; Schum, T; Schwandt, J; Stadie, H; Steinbrück, G; Thomsen, J; Wolf, R; Bauer, J; Buege, V; Cakir, A; Chwalek, T; Daeuwel, D; De Boer, W; Dierlamm, A; Dirkes, G; Feindt, M; Gruschke, J; Hackstein, C; Hartmann, F; Heinrich, M; Held, H; Hoffmann, K H; Honc, S; Kuhr, T; Martschei, D; Mueller, S; Müller, Th; Niegel, M; Oberst, O; Oehler, A; Ott, J; Peiffer, T; Piparo, D; Quast, G; Rabbertz, K; Ratnikov, F; Renz, M; Sabellek, A; Saout, C; Scheurer, A; Schieferdecker, P; Schilling, F-P; Schott, G; Simonis, H J; Stober, F M; Troendle, D; Wagner-Kuhr, J; Zeise, M; Zhukov, V; Ziebarth, E B; Daskalakis, G; Geralis, T; Kyriakis, A; Loukas, D; Manolakos, I; Markou, A; Markou, C; Mavrommatis, C; Petrakou, E; Gouskos, L; Katsas, P; Panagiotou, A; Evangelou, I; Kokkas, P; Manthos, N; Papadopoulos, I; Patras, V; Triantis, F A; Aranyi, A; Bencze, G; Boldizsar, L; Debreczeni, G; Hajdu, C; Horvath, D; Kapusi, A; Krajczar, K; Laszlo, A; Sikler, F; Vesztergombi, G; Beni, N; Molnar, J; Palinkas, J; Szillasi, Z; Veszpremi, V; Raics, P; Trocsanyi, Z L; Ujvari, B; Bansal, S; Beri, S B; Bhatnagar, V; Jindal, M; Kaur, M; Kohli, J M; Mehta, M Z; Nishu, N; Saini, L K; Sharma, A; Sharma, R; Singh, A P; Singh, J B; Singh, S P; Ahuja, S; Bhattacharya, S; Chauhan, S; Choudhary, B C; Gupta, P; Jain, S; Jain, S; Kumar, A; Ranjan, K; Shivpuri, R K; Choudhury, R K; Dutta, D; Kailas, S; Kataria, S K; Mohanty, A K; Pant, L M; Shukla, P; Suggisetti, P; Aziz, T; Guchait, M; Gurtu, A; Maity, M; Majumder, D; Majumder, G; Mazumdar, K; Mohanty, G B; Saha, A; Sudhakar, K; Wickramage, N; Banerjee, S; Dugad, S; Mondal, N K; Arfaei, H; Bakhshiansohi, H; Fahim, A; Jafari, A; Mohammadi Najafabadi, M; Paktinat Mehdiabadi, S; Safarzadeh, B; Zeinali, M; Abbrescia, M; Barbone, L; Colaleo, A; Creanza, D; De Filippis, N; De Palma, M; Dimitrov, A; Fedele, F; Fiore, L; Iaselli, G; Lusito, L; Maggi, G; Maggi, M; Manna, N; Marangelli, B; My, S; Nuzzo, S; Pierro, G A; Pompili, A; Pugliese, G; Romano, F; Roselli, G; Selvaggi, G; Silvestris, L; Trentadue, R; Tupputi, S; Zito, G; Abbiendi, G; Benvenuti, A C; Bonacorsi, D; Braibant-Giacomelli, S; Capiluppi, P; Castro, A; Cavallo, F R; Codispoti, G; Cuffiani, M; Fanfani, A; Fasanella, D; Giacomelli, P; Giunta, M; Grandi, C; Marcellini, S; Masetti, G; Montanari, A; Navarria, F L; Odorici, F; Perrotta, A; Rossi, A M; Rovelli, T; Siroli, G; Travaglini, R; Albergo, S; Cappello, G; Chiorboli, M; Costa, S; Tricomi, A; Tuve, C; Barbagli, G; Broccolo, G; Ciulli, V; Civinini, C; D'Alessandro, R; Focardi, E; Frosali, S; Gallo, E; Genta, C; Lenzi, P; Meschini, M; Paoletti, S; Sguazzoni, G; Tropiano, A; Benussi, L; Bianco, S; Colafranceschi, S; Fabbri, F; Piccolo, D; Fabbricatore, P; Musenich, R; Benaglia, A; Cerati, G B; De Guio, F; Di Matteo, L; Ghezzi, A; Govoni, P; Malberti, M; Malvezzi, S; Martelli, A; Massironi, A; Menasce, D; Miccio, V; Moroni, L; Negri, P; Paganoni, M; Pedrini, D; Ragazzi, S; Redaelli, N; Sala, S; Salerno, R; Tabarelli de Fatis, T; Tancini, V; Taroni, S; Buontempo, S; Cimmino, A; De Cosa, A; De Gruttola, M; Fabozzi, F; Iorio, A O M; Lista, L; Noli, P; Paolucci, P; Azzi, P; Bacchetta, N; Bellan, P; Bisello, D; Carlin, R; Checchia, P; Conti, E; De Mattia, M; Dorigo, T; Dosselli, U; Gasparini, F; Gasparini, U; Giubilato, P; Gresele, A; Lacaprara, S; Lazzizzera, I; Margoni, M; Mazzucato, M; Meneguzzo, A T; Nespolo, M; Perrozzi, L; Pozzobon, N; Ronchese, P; Simonetto, F; Torassa, E; Tosi, M; Vanini, S; Zotto, P; Zumerle, G; Baesso, P; Berzano, U; Riccardi, C; Torre, P; Vitulo, P; Viviani, C; Biasini, M; Bilei, G M; Caponeri, B; Fanò, L; Lariccia, P; Lucaroni, A; Mantovani, G; Menichelli, M; Nappi, A; Santocchia, A; Servoli, L; Valdata, M; Volpe, R; Azzurri, P; Bagliesi, G; Bernardini, J; Boccali, T; Castaldi, R; Dagnolo, R T; Dell'orso, R; Fiori, F; Foà, L; Giassi, A; Kraan, A; Ligabue, F; Lomtadze, T; Martini, L; Messineo, A; Palla, F; Palmonari, F; Segneri, G; Serban, A T; Spagnolo, P; Tenchini, R; Tonelli, G; Venturi, A; Verdini, P G; Barone, L; Cavallari, F; Del Re, D; Di Marco, E; Diemoz, M; Franci, D; Grassi, M; Longo, E; Organtini, G; Palma, A; Pandolfi, F; Paramatti, R; Rahatlou, S; Amapane, N; Arcidiacono, R; Argiro, S; Arneodo, M; Biino, C; Botta, C; Cartiglia, N; Castello, R; Costa, M; Demaria, N; Graziano, A; Mariotti, C; Marone, M; Maselli, S; Migliore, E; Mila, G; Monaco, V; Musich, M; Obertino, M M; Pastrone, N; Pelliccioni, M; Romero, A; Ruspa, M; Sacchi, R; Solano, A; Staiano, A; Trocino, D; Vilela Pereira, A; Ambroglini, F; Belforte, S; Cossutti, F; Della Ricca, G; Gobbo, B; Montanino, D; Penzo, A; Chang, S; Chung, J; Kim, D H; Kim, G N; Kim, J E; Kong, D J; Park, H; Son, D C; Kim, Zero; Kim, J Y; Song, S; Hong, B; Kim, H; Kim, J H; Kim, T J; Lee, K S; Moon, D H; Park, S K; Rhee, H B; Sim, K S; Choi, M; Kang, S; Kim, H; Park, C; Park, I C; Park, S; Choi, S; Choi, Y; Choi, Y K; Goh, J; Lee, J; Lee, S; Seo, H; Yu, I; Janulis, M; Martisiute, D; Petrov, P; Sabonis, T; Castilla Valdez, H; De La Cruz Burelo, E; Lopez-Fernandez, R; Sánchez Hernández, A; Villaseñor-Cendejas, L M; Carrillo Moreno, S; Salazar Ibarguen, H A; Casimiro Linares, E; Morelos Pineda, A; Reyes-Santos, M A; Allfrey, P; Krofcheck, D; Tam, J; Butler, P H; Signal, T; Williams, J C; Ahmad, M; Ahmed, I; Asghar, M I; Hoorani, H R; Khan, W A; Khurshid, T; Qazi, S; Cwiok, M; Dominik, W; Doroba, K; Konecki, M; Krolikowski, J; Frueboes, T; Gokieli, R; Górski, M; Kazana, M; Nawrocki, K; Szleper, M; Wrochna, G; Zalewski, P; Almeida, N; David, A; Faccioli, P; Ferreira Parracho, P G; Gallinaro, M; Mini, G; Musella, P; Nayak, A; Raposo, L; Ribeiro, P Q; Seixas, J; Silva, P; Soares, D; Varela, J; Wöhri, H K; Altsybeev, I; Belotelov, I; Bunin, P; Finger, M; Finger, M; Golutvin, I; Kamenev, A; Karjavin, V; Kozlov, G; Lanev, A; Moisenz, P; Palichik, V; Perelygin, V; Shmatov, S; Smirnov, V; Volodko, A; Zarubin, A; Bondar, N; Golovtsov, V; Ivanov, Y; Kim, V; Levchenko, P; Smirnov, I; Sulimov, V; Uvarov, L; Vavilov, S; Vorobyev, A; Andreev, Yu; Gninenko, S; Golubev, N; Kirsanov, M; Krasnikov, N; Matveev, V; Pashenkov, A; Toropin, A; Troitsky, S; Epshteyn, V; Gavrilov, V; Ilina, N; Kaftanov, V; Kossov, M; Krokhotin, A; Kuleshov, S; Oulianov, A; Safronov, G; Semenov, S; Shreyber, I; Stolin, V; Vlasov, E; Zhokin, A; Boos, E; Dubinin, M; Dudko, L; Ershov, A; Gribushin, A; Kodolova, O; Lokhtin, I; Obraztsov, S; Petrushanko, S; Sarycheva, L; Savrin, V; Snigirev, A; Andreev, V; Dremin, I; Kirakosyan, M; Rusakov, S V; Vinogradov, A; Azhgirey, I; Bitioukov, S; Datsko, K; Grishin, V; Kachanov, V; Konstantinov, D; Krychkine, V; Petrov, V; Ryutin, R; Slabospitsky, S; Sobol, A; Sytine, A; Tourtchanovitch, L; Troshin, S; Tyurin, N; Uzunian, A; Volkov, A; Adzic, P; Djordjevic, M; Krpic, D; Maletic, D; Milosevic, J; Puzovic, J; Aguilar-Benitez, M; Alcaraz Maestre, J; Arce, P; Battilana, C; Calvo, E; Cepeda, M; Cerrada, M; Chamizo Llatas, M; Colino, N; De La Cruz, B; Diez Pardos, C; Fernandez Bedoya, C; Fernández Ramos, J P; Ferrando, A; Flix, J; Fouz, M C; Garcia-Abia, P; Gonzalez Lopez, O; Goy Lopez, S; Hernandez, J M; Josa, M I; Merino, G; Puerta Pelayo, J; Redondo, I; Romero, L; Santaolalla, J; Willmott, C; Albajar, C; de Trocóniz, J F; Cuevas, J; Fernandez Menendez, J; Gonzalez Caballero, I; Lloret Iglesias, L; Vizan Garcia, J M; Cabrillo, I J; Calderon, A; Chuang, S H; Diaz Merino, I; Diez Gonzalez, C; Duarte Campderros, J; Fernandez, M; Gomez, G; Gonzalez Sanchez, J; Gonzalez Suarez, R; Jorda, C; Lobelle Pardo, P; Lopez Virto, A; Marco, J; Marco, R; Martinez Rivero, C; Martinez Ruiz Del Arbol, P; Matorras, F; Rodrigo, T; Ruiz Jimeno, A; Scodellaro, L; Sobron Sanudo, M; Vila, I; Vilar Cortabitarte, R; Abbaneo, D; Auffray, E; Baillon, P; Ball, A H; Barney, D; Beaudette, F; Bellan, R; Benedetti, D; Bernet, C; Bialas, W; Bloch, P; Bocci, A; Bolognesi, S; Breuker, H; Brona, G; Bunkowski, K; Camporesi, T; Cano, E; Cattai, A; Cerminara, G; Christiansen, T; Coarasa Perez, J A; Covarelli, R; Curé, B; Dahms, T; De Roeck, A; Elliott-Peisert, A; Funk, W; Gaddi, A; Gennai, S; Gerwig, H; Gigi, D; Gill, K; Giordano, D; Glege, F; Gomez-Reino Garrido, R; Gowdy, S; Guiducci, L; Hansen, M; Hartl, C; Harvey, J; Hegner, B; Henderson, C; Hoffmann, H F; Honma, A; Innocente, V; Janot, P; Lecoq, P; Leonidopoulos, C; Lourenço, C; Macpherson, A; Mäki, T; Malgeri, L; Mannelli, M; Masetti, L; Mavromanolakis, G; Meijers, F; Mersi, S; Meschi, E; Moser, R; Mozer, M U; Mulders, M; Nesvold, E; Orsini, L; Perez, E; Petrilli, A; Pfeiffer, A; Pierini, M; Pimiä, M; Racz, A; Rolandi, G; Rovelli, C; Rovere, M; Sakulin, H; Schäfer, C; Schwick, C; Segoni, I; Sharma, A; Siegrist, P; Simon, M; Sphicas, P; Spiga, D; Spiropulu, M; Stöckli, F; Traczyk, P; Tropea, P; Tsirou, A; Veres, G I; Vichoudis, P; Voutilainen, M; Zeuner, W D; Bertl, W; Deiters, K; Erdmann, W; Gabathuler, K; Horisberger, R; Ingram, Q; Kaestli, H C; König, S; Kotlinski, D; Langenegger, U; Meier, F; Renker, D; Rohe, T; Sibille, J; Starodumov, A; Caminada, L; Chen, Z; Cittolin, S; Dissertori, G; Dittmar, M; Eugster, J; Freudenreich, K; Grab, C; Hervé, A; Hintz, W; Lecomte, P; Lustermann, W; Marchica, C; Meridiani, P; Milenovic, P; Moortgat, F; Nardulli, A; Nef, P; Nessi-Tedaldi, F; Pape, L; Pauss, F; Punz, T; Rizzi, A; Ronga, F J; Sala, L; Sanchez, A K; Sawley, M-C; Schinzel, D; Stieger, B; Tauscher, L; Thea, A; Theofilatos, K; Treille, D; Weber, M; Wehrli, L; Weng, J; Amsler, C; Chiochia, V; De Visscher, S; Ivova Rikova, M; Millan Mejias, B; Regenfus, C; Robmann, P; Rommerskirchen, T; Schmidt, A; Tsirigkas, D; Wilke, L; Chang, Y H; Chen, K H; Chen, W T; Go, A; Kuo, C M; Li, S W; Lin, W; Liu, M H; Lu, Y J; Wu, J H; Yu, S S; Bartalini, P; Chang, P; Chang, Y H; Chang, Y W; Chao, Y; Chen, K F; Hou, W-S; Hsiung, Y; Kao, K Y; Lei, Y J; Lin, S W; Lu, R-S; Shiu, J G; Tzeng, Y M; Ueno, K; Wang, C C; Wang, M; Wei, J T; Adiguzel, A; Ayhan, A; Bakirci, M N; Cerci, S; Demir, Z; Dozen, C; Dumanoglu, I; Eskut, E; Girgis, S; Gökbulut, G; Güler, Y; Gurpinar, E; Hos, I; Kangal, E E; Karaman, T; Kayis Topaksu, A; Nart, A; Onengüt, G; Ozdemir, K; Ozturk, S; Polatöz, A; Sahin, O; Sengul, O; Sogut, K; Tali, B; Topakli, H; Uzun, D; Vergili, L N; Vergili, M; Zorbilmez, C; Akin, I V; Aliev, T; Bilmis, S; Deniz, M; Gamsizkan, H; Guler, A M; Ocalan, K; Ozpineci, A; Serin, M; Sever, R; Surat, U E; Yildirim, E; Zeyrek, M; Deliomeroglu, M; Demir, D; Gülmez, E; Halu, A; Isildak, B; Kaya, M; Kaya, O; Ozbek, M; Ozkorucuklu, S; Sonmez, N; Levchuk, L; Bell, P; Bostock, F; Brooke, J J; Cheng, T L; Cussans, D; Frazier, R; Goldstein, J; Hansen, M; Heath, G P; Heath, H F; Hill, C; Huckvale, B; Jackson, J; Kreczko, L; Mackay, C K; Metson, S; Newbold, D M; Nirunpong, K; Smith, V J; Ward, S; Basso, L; Bell, K W; Belyaev, A; Brew, C; Brown, R M; Camanzi, B; Cockerill, D J A; Coughlan, J A; Harder, K; Harper, S; Kennedy, B W; Olaiya, E; Petyt, D; Radburn-Smith, B C; Shepherd-Themistocleous, C H; Tomalin, I R; Womersley, W J; Worm, S D; Bainbridge, R; Ball, G; Ballin, J; Beuselinck, R; Buchmuller, O; Colling, D; Cripps, N; Cutajar, M; Davies, G; Della Negra, M; Foudas, C; Fulcher, J; Futyan, D; Guneratne Bryer, A; Hall, G; Hatherell, Z; Hays, J; Iles, G; Karapostoli, G; Lyons, L; Magnan, A-M; Marrouche, J; Nandi, R; Nash, J; Nikitenko, A; Papageorgiou, A; Pesaresi, M; Petridis, K; Pioppi, M; Raymond, D M; Rompotis, N; Rose, A; Ryan, M J; Seez, C; Sharp, P; Sparrow, A; Stoye, M; Tapper, A; Tourneur, S; Vazquez Acosta, M; Virdee, T; Wakefield, S; Wardrope, D; Whyntie, T; Barrett, M; Chadwick, M; Cole, J E; Hobson, P R; Khan, A; Kyberd, P; Leslie, D; Reid, I D; Teodorescu, L; Bose, T; Clough, A; Heister, A; St John, J; Lawson, P; Lazic, D; Rohlf, J; Sulak, L; Andrea, J; Avetisyan, A; Bhattacharya, S; Chou, J P; Cutts, D; Esen, S; Heintz, U; Jabeen, S; Kukartsev, G; Landsberg, G; Narain, M; Nguyen, D; Speer, T; Tsang, K V; Borgia, M A; Breedon, R; Calderon De La Barca Sanchez, M; Cebra, D; Chertok, M; Conway, J; Cox, P T; Dolen, J; Erbacher, R; Friis, E; Ko, W; Kopecky, A; Lander, R; Liu, H; Maruyama, S; Miceli, T; Nikolic, M; Pellett, D; Robles, J; Schwarz, T; Searle, M; Smith, J; Squires, M; Tripathi, M; Vasquez Sierra, R; Veelken, C; Andreev, V; Arisaka, K; Cline, D; Cousins, R; Deisher, A; Erhan, S; Farrell, C; Felcini, M; Hauser, J; Ignatenko, M; Jarvis, C; Plager, C; Rakness, G; Schlein, P; Tucker, J; Valuev, V; Wallny, R; Babb, J; Clare, R; Ellison, J; Gary, J W; Hanson, G; Jeng, G Y; Kao, S C; Liu, F; Liu, H; Luthra, A; Nguyen, H; Pasztor, G; Satpathy, A; Shen, B C; Stringer, R; Sturdy, J; Sumowidagdo, S; Wilken, R; Wimpenny, S; Andrews, W; Branson, J G; Dusinberre, E; Evans, D; Golf, F; Holzner, A; Kelley, R; Lebourgeois, M; Letts, J; Mangano, B; Muelmenstaedt, J; Padhi, S; Palmer, C; Petrucciani, G; Pi, H; Pieri, M; Ranieri, R; Sani, M; Sharma, V; Simon, S; Tu, Y; Vartak, A; Würthwein, F; Yagil, A; Barge, D; Blume, M; Campagnari, C; D'Alfonso, M; Danielson, T; Garberson, J; Incandela, J; Justus, C; Kalavase, P; Koay, S A; Kovalskyi, D; Krutelyov, V; Lamb, J; Lowette, S; Pavlunin, V; Rebassoo, F; Ribnik, J; Richman, J; Rossin, R; Stuart, D; To, W; Vlimant, J R; Witherell, M; Bornheim, A; Bunn, J; Gataullin, M; Kcira, D; Litvine, V; Ma, Y; Newman, H B; Rogan, C; Shin, K; Timciuc, V; Veverka, J; Wilkinson, R; Yang, Y; Zhu, R Y; Akgun, B; Carroll, R; Ferguson, T; Jang, D W; Jun, S Y; Paulini, M; Russ, J; Terentyev, N; Vogel, H; Vorobiev, I; Cumalat, J P; Dinardo, M E; Drell, B R; Ford, W T; Heyburn, B; Luiggi Lopez, E; Nauenberg, U; Smith, J G; Stenson, K; Ulmer, K A; Wagner, S R; Zang, S L; Agostino, L; Alexander, J; Blekman, F; Chatterjee, A; Das, S; Eggert, N; Fields, L J; Gibbons, L K; Heltsley, B; Hopkins, W; Khukhunaishvili, A; Kreis, B; Kuznetsov, V; Nicolas Kaufman, G; Patterson, J R; Puigh, D; Riley, D; Ryd, A; Shi, X; Sun, W; Teo, W D; Thom, J; Thompson, J; Vaughan, J; Weng, Y; Wittich, P; Biselli, A; Cirino, G; Winn, D; Abdullin, S; Albrow, M; Anderson, J; Apollinari, G; Atac, M; Bakken, J A; Banerjee, S; Bauerdick, L A T; Beretvas, A; Berryhill, J; Bhat, P C; Bloch, I; Borcherding, F; Burkett, K; Butler, J N; Chetluru, V; Cheung, H W K; Chlebana, F; Cihangir, S; Demarteau, M; Eartly, D P; Elvira, V D; Fisk, I; Freeman, J; Gao, Y; Gottschalk, E; Green, D; Gutsche, O; Hahn, A; Hanlon, J; Harris, R M; James, E; Jensen, H; Johnson, M; Joshi, U; Khatiwada, R; Kilminster, B; Klima, B; Kousouris, K; Kunori, S; Kwan, S; Limon, P; Lipton, R; Lykken, J; Maeshima, K; Marraffino, J M; Mason, D; McBride, P; McCauley, T; Miao, T; Mishra, K; Mrenna, S; Musienko, Y; Newman-Holmes, C; O'Dell, V; Popescu, S; Pordes, R; Prokofyev, O; Saoulidou, N; Sexton-Kennedy, E; Sharma, S; Smith, R P; Soha, A; Spalding, W J; Spiegel, L; Tan, P; Taylor, L; Tkaczyk, S; Uplegger, L; Vaandering, E W; Vidal, R; Whitmore, J; Wu, W; Yumiceva, F; Yun, J C; Acosta, D; Avery, P; Bourilkov, D; Chen, M; Di Giovanni, G P; Dobur, D; Drozdetskiy, A; Field, R D; Fu, Y; Furic, I K; Gartner, J; Kim, B; Klimenko, S; Konigsberg, J; Korytov, A; Kotov, K; Kropivnitskaya, A; Kypreos, T; Matchev, K; Mitselmakher, G; Pakhotin, Y; Piedra Gomez, J; Prescott, C; Remington, R; Schmitt, M; Scurlock, B; Sellers, P; Wang, D; Yelton, J; Zakaria, M; Ceron, C; Gaultney, V; Kramer, L; Lebolo, L M; Linn, S; Markowitz, P; Martinez, G; Mesa, D; Rodriguez, J L; Adams, T; Askew, A; Chen, J; Diamond, B; Gleyzer, S V; Haas, J; Hagopian, S; Hagopian, V; Jenkins, M; Johnson, K F; Prosper, H; Sekmen, S; Veeraraghavan, V; Baarmand, M M; Guragain, S; Hohlmann, M; Kalakhety, H; Mermerkaya, H; Ralich, R; Vodopiyanov, I; Adams, M R; Anghel, I M; Apanasevich, L; Bazterra, V E; Betts, R R; Callner, J; Cavanaugh, R; Dragoiu, C; Garcia-Solis, E J; Gerber, C E; Hofman, D J; Khalatian, S; Lacroix, F; Shabalina, E; Smoron, A; Strom, D; Varelas, N; Akgun, U; Albayrak, E A; Bilki, B; Cankocak, K; Clarida, W; Duru, F; Lae, C K; McCliment, E; Merlo, J-P; Mestvirishvili, A; Moeller, A; Nachtman, J; Newsom, C R; Norbeck, E; Olson, J; Onel, Y; Ozok, F; Sen, S; Wetzel, J; Yetkin, T; Yi, K; Barnett, B A; Blumenfeld, B; Bonato, A; Eskew, C; Fehling, D; Giurgiu, G; Gritsan, A V; Guo, Z J; Hu, G; Maksimovic, P; Rappoccio, S; Swartz, M; Tran, N V; Whitbeck, A; Baringer, P; Bean, A; Benelli, G; Grachov, O; Murray, M; Radicci, V; Sanders, S; Wood, J S; Zhukova, V; Bandurin, D; Bolton, T; Chakaberia, I; Ivanov, A; Kaadze, K; Maravin, Y; Shrestha, S; Svintradze, I; Wan, Z; Gronberg, J; Lange, D; Wright, D; Baden, D; Boutemeur, M; Eno, S C; Ferencek, D; Hadley, N J; Kellogg, R G; Kirn, M; Mignerey, A; Rossato, K; Rumerio, P; Santanastasio, F; Skuja, A; Temple, J; Tonjes, M B; Tonwar, S C; Twedt, E; Alver, B; Bauer, G; Bendavid, J; Busza, W; Butz, E; Cali, I A; Chan, M; D'Enterria, D; Everaerts, P; Gomez Ceballos, G; Goncharov, M; Hahn, K A; Harris, P; Kim, Y; Klute, M; Lee, Y-J; Li, W; Loizides, C; Luckey, P D; Ma, T; Nahn, S; Paus, C; Roland, C; Roland, G; Rudolph, M; Stephans, G S F; Sumorok, K; Sung, K; Wenger, E A; Wyslouch, B; Xie, S; Yilmaz, Y; Yoon, A S; Zanetti, M; Cole, P; Cooper, S I; Cushman, P; Dahmes, B; De Benedetti, A; Dudero, P R; Franzoni, G; Haupt, J; Klapoetke, K; Kubota, Y; Mans, J; Rekovic, V; Rusack, R; Sasseville, M; Singovsky, A; Cremaldi, L M; Godang, R; Kroeger, R; Perera, L; Rahmat, R; Sanders, D A; Sonnek, P; Summers, D; Bloom, K; Bose, S; Butt, J; Claes, D R; Dominguez, A; Eads, M; Keller, J; Kelly, T; Kravchenko, I; Lazo-Flores, J; Lundstedt, C; Malbouisson, H; Malik, S; Snow, G R; Baur, U; Iashvili, I; Kharchilava, A; Kumar, A; Smith, K; Strang, M; Zennamo, J; Alverson, G; Barberis, E; Baumgartel, D; Boeriu, O; Reucroft, S; Swain, J; Wood, D; Zhang, J; Anastassov, A; Kubik, A; Ofierzynski, R A; Pozdnyakov, A; Schmitt, M; Stoynev, S; Velasco, M; Won, S; Antonelli, L; Berry, D; Hildreth, M; Jessop, C; Karmgard, D J; Kolb, J; Kolberg, T; Lannon, K; Lynch, S; Marinelli, N; Morse, D M; Ruchti, R; Slaunwhite, J; Valls, N; Warchol, J; Wayne, M; Ziegler, J; Bylsma, B; Durkin, L S; Gu, J; Killewald, P; Ling, T Y; Williams, G; Adam, N; Berry, E; Elmer, P; Gerbaudo, D; Halyo, V; Hunt, A; Jones, J; Laird, E; Lopes Pegna, D; Marlow, D; Medvedeva, T; Mooney, M; Olsen, J; Piroué, P; Stickland, D; Tully, C; Werner, J S; Zuranski, A; Acosta, J G; Huang, X T; Lopez, A; Mendez, H; Oliveros, S; Ramirez Vargas, J E; Zatzerklyaniy, A; Alagoz, E; Barnes, V E; Bolla, G; Borrello, L; Bortoletto, D; Everett, A; Garfinkel, A F; Gecse, Z; Gutay, L; Jones, M; Koybasi, O; Laasanen, A T; Leonardo, N; Liu, C; Maroussov, V; Merkel, P; Miller, D H; Neumeister, N; Potamianos, K; Shipsey, I; Silvers, D; Yoo, H D; Zablocki, J; Zheng, Y; Jindal, P; Parashar, N; Cuplov, V; Ecklund, K M; Geurts, F J M; Liu, J H; Morales, J; Padley, B P; Redjimi, R; Roberts, J; Betchart, B; Bodek, A; Chung, Y S; de Barbaro, P; Demina, R; Flacher, H; Garcia-Bellido, A; Gotra, Y; Han, J; Harel, A; Miner, D C; Orbaker, D; Petrillo, G; Vishnevskiy, D; Zielinski, M; Bhatti, A; Demortier, L; Goulianos, K; Hatakeyama, K; Lungu, G; Mesropian, C; Yan, M; Atramentov, O; Gershtein, Y; Gray, R; Halkiadakis, E; Hidas, D; Hits, D; Lath, A; Rose, K; Schnetzer, S; Somalwar, S; Stone, R; Thomas, S; Cerizza, G; Hollingsworth, M; Spanier, S; Yang, Z C; York, A; Asaadi, J; Eusebi, R; Gilmore, J; Gurrola, A; Kamon, T; Khotilovich, V; Montalvo, R; Nguyen, C N; Pivarski, J; Safonov, A; Sengupta, S; Toback, D; Weinberger, M; Akchurin, N; Bardak, C; Damgov, J; Jeong, C; Kovitanggoon, K; Lee, S W; Mane, P; Roh, Y; Sill, A; Volobouev, I; Wigmans, R; Yazgan, E; Appelt, E; Brownson, E; Engh, D; Florez, C; Gabella, W; Johns, W; Kurt, P; Maguire, C; Melo, A; Sheldon, P; Velkovska, J; Arenton, M W; Balazs, M; Buehler, M; Conetti, S; Cox, B; Hirosky, R; Ledovskoy, A; Neu, C; Yohay, R; Gollapinni, S; Gunthoti, K; Harr, R; Karchin, P E; Mattson, M; Milstène, C; Sakharov, A; Anderson, M; Bachtis, M; Bellinger, J N; Carlsmith, D; Dasu, S; Dutta, S; Efron, J; Gray, L; Grogg, K S; Grothe, M; Herndon, M; Klabbers, P; Klukas, J; Lanaro, A; Lazaridis, C; Leonard, J; Lomidze, D; Loveless, R; Mohapatra, A; Polese, G; Reeder, D; Savin, A; Smith, W H; Swanson, J; Weinberg, M

2010-07-16

Bose-Einstein correlations have been measured using samples of proton-proton collisions at 0.9 and 2.36 TeV center-of-mass energies, recorded by the CMS experiment at the CERN Large Hadron Collider. The signal is observed in the form of an enhancement of pairs of same-sign charged particles with small relative four-momentum. The size of the correlated particle emission region is seen to increase significantly with the particle multiplicity of the event.

AGIS: The ATLAS Grid Information System

NASA Astrophysics Data System (ADS)

Anisenkov, Alexey; Belov, Sergey; Di Girolamo, Alessandro; Gayazov, Stavro; Klimentov, Alexei; Oleynik, Danila; Senchenko, Alexander

2012-12-01

ATLAS is a particle physics experiment at the Large Hadron Collider at CERN. The experiment produces petabytes of data annually through simulation production and tens petabytes of data per year from the detector itself. The ATLAS Computing model embraces the Grid paradigm and a high degree of decentralization and computing resources able to meet ATLAS requirements of petabytes scale data operations. In this paper we present ATLAS Grid Information System (AGIS) designed to integrate configuration and status information about resources, services and topology of whole ATLAS Grid needed by ATLAS Distributed Computing applications and services.

AGIS: The ATLAS Grid Information System

NASA Astrophysics Data System (ADS)

Anisenkov, A.; Di Girolamo, A.; Klimentov, A.; Oleynik, D.; Petrosyan, A.; Atlas Collaboration

2014-06-01

ATLAS, a particle physics experiment at the Large Hadron Collider at CERN, produced petabytes of data annually through simulation production and tens of petabytes of data per year from the detector itself. The ATLAS computing model embraces the Grid paradigm and a high degree of decentralization and computing resources able to meet ATLAS requirements of petabytes scale data operations. In this paper we describe the ATLAS Grid Information System (AGIS), designed to integrate configuration and status information about resources, services and topology of the computing infrastructure used by the ATLAS Distributed Computing applications and services.

Liquid Argon Calorimetry for ATLAS

NASA Astrophysics Data System (ADS)

Robinson, Alan

2008-05-01

This summer, the largest collaborative physics project since the Manhattan project will go online. One of four experiments for the Large Hadron Collider at CERN in Geneva, ATLAS, employs over 2000 people. Canadians have helped design, construct, and calibrate the liquid argon calorimeters for ATLAS to capture the products of the high energy collisions produced by the LHC. From an undergraduate's perspective, explore how these calorimeters are made to handle their harsh requirement. From nearly a billion proton-proton collisions a second, physicists hope to discover the Higgs boson and other new fundamental particles.

The upgrade of the ATLAS first-level calorimeter trigger

NASA Astrophysics Data System (ADS)

Yamamoto, Shimpei; Atlas Collaboration

2016-07-01

The first-level calorimeter trigger (L1Calo) had operated successfully through the first data taking phase of the ATLAS experiment at the CERN Large Hadron Collider. Towards forthcoming LHC runs, a series of upgrades is planned for L1Calo to face new challenges posed by the upcoming increases of the beam energy and the luminosity. This paper reviews the ATLAS L1Calo trigger upgrade project that introduces new architectures for the liquid-argon calorimeter trigger readout and the L1Calo trigger processing system.

The NLC technical program

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burke, D.L.

1998-07-01

There are important goals in particle physics to be addressed by a TeV-scale electron-positron linear collider. Recent developments in accelerator physics and technologies aimed for the realization of such a collider are discussed in this paper.

Flow harmonics from self-consistent particlization of a viscous fluid

NASA Astrophysics Data System (ADS)

Wolff, Zack; Molnar, Denes

2017-10-01

The quantitative extraction of quark-gluon plasma (QGP) properties from heavy-ion data, such as its specific shear viscosity η /s , typically requires comparison to viscous hydrodynamic or "hybrid" hydrodynamics + transport simulations. In either case, one has to convert the fluid to hadrons, yet without additional theory input the conversion is ambiguous for dissipative fluids. Here, shear viscous phase-space corrections calculated using linearized transport theory are applied in Cooper-Frye freeze-out to quantify the effects on anisotropic flow coefficients vn(pT) at the energies available at both the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider. Expanding upon our previous flow harmonics studies [D. Molnar and Z. Wolff, Phys. Rev. C 95, 024903 (2017), 10.1103/PhysRevC.95.024903; Z. Wolff and D. Molnar, J. Phys.: Conf. Ser. 535, 012020 (2014), 10.1088/1742-6596/535/1/012020], we calculate pion and proton v2(pT) , v4(pT) , and v6(pT) , but here we incorporate a hadron gas that is chemically frozen below a temperature of 175 MeV and use hypersurfaces from realistic viscous hydrodynamic simulations. For additive quark model cross sections and relative phase-space corrections with p3 /2 momentum dependence rather than the quadratic Grad form, we find at moderately high transverse momentum noticeably higher v4(pT) and v6(pT) for protons than for pions. In addition, the value of η /s deduced from elliptic flow data differs by nearly 50% from the value extracted using the naive "democratic Grad" form of freeze-out distributions. To facilitate the use of the self-consistent viscous corrections calculated here in hydrodynamic and hybrid calculations, we also present convenient parametrizations of the corrections for the various hadron species.

Centrality dependence of pion freeze-out radii in Pb-Pb collisions at √{sN N}=2.76 TeV

NASA Astrophysics Data System (ADS)

Adam, J.; Adamová, D.; Aggarwal, M. M.; Aglieri Rinella, G.; Agnello, M.; Agrawal, N.; Ahammed, Z.; Ahn, S. U.; Aimo, I.; Aiola, S.; Ajaz, M.; Akindinov, A.; Alam, S. N.; Aleksandrov, D.; Alessandro, B.; Alexandre, D.; Alfaro Molina, R.; Alici, A.; Alkin, A.; Almaraz, J. R. M.; Alme, J.; Alt, T.; Altinpinar, S.; Altsybeev, I.; Alves Garcia Prado, C.; Andrei, C.; Andronic, A.; Anguelov, V.; Anielski, J.; Antičić, T.; Antinori, F.; Antonioli, P.; Aphecetche, L.; Appelshäuser, H.; Arcelli, S.; Armesto, N.; Arnaldi, R.; Arsene, I. C.; Arslandok, M.; Audurier, B.; Augustinus, A.; Averbeck, R.; Azmi, M. D.; Bach, M.; Badalà, A.; Baek, Y. W.; Bagnasco, S.; Bailhache, R.; Bala, R.; Baldisseri, A.; Baltasar Dos Santos Pedrosa, F.; Baral, R. C.; Barbano, A. M.; Barbera, R.; Barile, F.; Barnaföldi, G. G.; Barnby, L. S.; Barret, V.; Bartalini, P.; Barth, K.; Bartke, J.; Bartsch, E.; Basile, M.; Bastid, N.; Basu, S.; Bathen, B.; Batigne, G.; Batista Camejo, A.; Batyunya, B.; Batzing, P. C.; Bearden, I. G.; Beck, H.; Bedda, C.; Behera, N. K.; Belikov, I.; Bellini, F.; Bello Martinez, H.; Bellwied, R.; Belmont, R.; Belmont-Moreno, E.; Belyaev, V.; Bencedi, G.; Beole, S.; Berceanu, I.; Bercuci, A.; Berdnikov, Y.; Berenyi, D.; Bertens, R. A.; Berzano, D.; Betev, L.; Bhasin, A.; Bhat, I. R.; Bhati, A. K.; Bhattacharjee, B.; Bhom, J.; Bianchi, L.; Bianchi, N.; Bianchin, C.; Bielčík, J.; Bielčíková, J.; Bilandzic, A.; Biswas, R.; Biswas, S.; Bjelogrlic, S.; Blair, J. T.; Blanco, F.; Blau, D.; Blume, C.; Bock, F.; Bogdanov, A.; Bøggild, H.; Boldizsár, L.; Bombara, M.; Book, J.; Borel, H.; Borissov, A.; Borri, M.; Bossú, F.; Botta, E.; Böttger, S.; Braun-Munzinger, P.; Bregant, M.; Breitner, T.; Broker, T. A.; Browning, T. A.; Broz, M.; Brucken, E. J.; Bruna, E.; Bruno, G. E.; Budnikov, D.; Buesching, H.; Bufalino, S.; Buncic, P.; Busch, O.; Buthelezi, Z.; Butt, J. B.; Buxton, J. T.; Caffarri, D.; Cai, X.; Caines, H.; Calero Diaz, L.; Caliva, A.; Calvo Villar, E.; Camerini, P.; Carena, F.; Carena, W.; Carnesecchi, F.; Castillo Castellanos, J.; Castro, A. J.; Casula, E. A. R.; Cavicchioli, C.; Ceballos Sanchez, C.; Cepila, J.; Cerello, P.; Cerkala, J.; Chang, B.; Chapeland, S.; Chartier, M.; Charvet, J. L.; Chattopadhyay, S.; Chattopadhyay, S.; Chelnokov, V.; Cherney, M.; Cheshkov, C.; Cheynis, B.; Chibante Barroso, V.; Chinellato, D. D.; Chochula, P.; Choi, K.; Chojnacki, M.; Choudhury, S.; Christakoglou, P.; Christensen, C. H.; Christiansen, P.; Chujo, T.; Chung, S. U.; Chunhui, Z.; Cicalo, C.; Cifarelli, L.; Cindolo, F.; Cleymans, J.; Colamaria, F.; Colella, D.; Collu, A.; Colocci, M.; Conesa Balbastre, G.; Conesa Del Valle, Z.; Connors, M. E.; Contreras, J. G.; Cormier, T. M.; Corrales Morales, Y.; Cortés Maldonado, I.; Cortese, P.; Cosentino, M. R.; Costa, F.; Crochet, P.; Cruz Albino, R.; Cuautle, E.; Cunqueiro, L.; Dahms, T.; Dainese, A.; Danu, A.; Das, D.; Das, I.; Das, S.; Dash, A.; Dash, S.; de, S.; de Caro, A.; de Cataldo, G.; de Cuveland, J.; de Falco, A.; de Gruttola, D.; De Marco, N.; de Pasquale, S.; Deisting, A.; Deloff, A.; Dénes, E.; D'Erasmo, G.; di Bari, D.; di Mauro, A.; di Nezza, P.; Diaz Corchero, M. A.; Dietel, T.; Dillenseger, P.; Divià, R.; Djuvsland, Ø.; Dobrin, A.; Dobrowolski, T.; Domenicis Gimenez, D.; Dönigus, B.; Dordic, O.; Drozhzhova, T.; Dubey, A. K.; Dubla, A.; Ducroux, L.; Dupieux, P.; Ehlers, R. J.; Elia, D.; Engel, H.; Erazmus, B.; Erdemir, I.; Erhardt, F.; Eschweiler, D.; Espagnon, B.; Estienne, M.; Esumi, S.; Eum, J.; Evans, D.; Evdokimov, S.; Eyyubova, G.; Fabbietti, L.; Fabris, D.; Faivre, J.; Fantoni, A.; Fasel, M.; Feldkamp, L.; Felea, D.; Feliciello, A.; Feofilov, G.; Ferencei, J.; Fernández Téllez, A.; Ferreiro, E. G.; Ferretti, A.; Festanti, A.; Feuillard, V. J. G.; Figiel, J.; Figueredo, M. A. S.; Filchagin, S.; Finogeev, D.; Fiore, E. M.; Fleck, M. G.; Floris, M.; Foertsch, S.; Foka, P.; Fokin, S.; Fragiacomo, E.; Francescon, A.; Frankenfeld, U.; Fuchs, U.; Furget, C.; Furs, A.; Fusco Girard, M.; Gaardhøje, J. J.; Gagliardi, M.; Gago, A. M.; Gallio, M.; Gangadharan, D. R.; Ganoti, P.; Gao, C.; Garabatos, C.; Garcia-Solis, E.; Gargiulo, C.; Gasik, P.; Germain, M.; Gheata, A.; Gheata, M.; Ghosh, P.; Ghosh, S. K.; Gianotti, P.; Giubellino, P.; Giubilato, P.; Gladysz-Dziadus, E.; Glässel, P.; Goméz Coral, D. M.; Gomez Ramirez, A.; González-Zamora, P.; Gorbunov, S.; Görlich, L.; Gotovac, S.; Grabski, V.; Graczykowski, L. K.; Graham, K. L.; Grelli, A.; Grigoras, A.; Grigoras, C.; Grigoriev, V.; Grigoryan, A.; Grigoryan, S.; Grinyov, B.; Grion, N.; Grosse-Oetringhaus, J. F.; Grossiord, J.-Y.; Grosso, R.; Guber, F.; Guernane, R.; Guerzoni, B.; Gulbrandsen, K.; Gulkanyan, H.; Gunji, T.; Gupta, A.; Gupta, R.; Haake, R.; Haaland, Ø.; Hadjidakis, C.; Haiduc, M.; Hamagaki, H.; Hamar, G.; Hansen, A.; Harris, J. W.; Hartmann, H.; Harton, A.; Hatzifotiadou, D.; Hayashi, S.; Heckel, S. T.; Heide, M.; Helstrup, H.; Herghelegiu, A.; Herrera Corral, G.; Hess, B. A.; Hetland, K. F.; Hilden, T. E.; Hillemanns, H.; Hippolyte, B.; Hosokawa, R.; Hristov, P.; Huang, M.; Humanic, T. J.; Hussain, N.; Hussain, T.; Hutter, D.; Hwang, D. S.; Ilkaev, R.; Ilkiv, I.; Inaba, M.; Ippolitov, M.; Irfan, M.; Ivanov, M.; Ivanov, V.; Izucheev, V.; Jacobs, P. M.; Jadlovska, S.; Jahnke, C.; Jang, H. J.; Janik, M. A.; Jayarathna, P. H. S. Y.; Jena, C.; Jena, S.; Jimenez Bustamante, R. T.; Jones, P. G.; Jung, H.; Jusko, A.; Kalinak, P.; Kalweit, A.; Kamin, J.; Kang, J. H.; Kaplin, V.; Kar, S.; Karasu Uysal, A.; Karavichev, O.; Karavicheva, T.; Karayan, L.; Karpechev, E.; Kebschull, U.; Keidel, R.; Keijdener, D. L. D.; Keil, M.; Khan, K. H.; Khan, M. M.; Khan, P.; Khan, S. A.; Khanzadeev, A.; Kharlov, Y.; Kileng, B.; Kim, B.; Kim, D. W.; Kim, D. J.; Kim, H.; Kim, J. S.; Kim, M.; Kim, M.; Kim, S.; Kim, T.; Kirsch, S.; Kisel, I.; Kiselev, S.; Kisiel, A.; Kiss, G.; Klay, J. L.; Klein, C.; Klein, J.; Klein-Bösing, C.; Kluge, A.; Knichel, M. L.; Knospe, A. G.; Kobayashi, T.; Kobdaj, C.; Kofarago, M.; Kollegger, T.; Kolojvari, A.; Kondratiev, V.; Kondratyeva, N.; Kondratyuk, E.; Konevskikh, A.; Kopcik, M.; Kour, M.; Kouzinopoulos, C.; Kovalenko, O.; Kovalenko, V.; Kowalski, M.; Koyithatta Meethaleveedu, G.; Kral, J.; Králik, I.; Kravčáková, A.; Krelina, M.; Kretz, M.; Krivda, M.; Krizek, F.; Kryshen, E.; Krzewicki, M.; Kubera, A. M.; Kučera, V.; Kugathasan, T.; Kuhn, C.; Kuijer, P. G.; Kulakov, I.; Kumar, A.; Kumar, J.; Kumar, L.; Kurashvili, P.; Kurepin, A.; Kurepin, A. B.; Kuryakin, A.; Kushpil, S.; Kweon, M. J.; Kwon, Y.; La Pointe, S. L.; La Rocca, P.; Lagana Fernandes, C.; Lakomov, I.; Langoy, R.; Lara, C.; Lardeux, A.; Lattuca, A.; Laudi, E.; Lea, R.; Leardini, L.; Lee, G. R.; Lee, S.; Legrand, I.; Lehas, F.; Lemmon, R. C.; Lenti, V.; Leogrande, E.; León Monzón, I.; Leoncino, M.; Lévai, P.; Li, S.; Li, X.; Lien, J.; Lietava, R.; Lindal, S.; Lindenstruth, V.; Lippmann, C.; Lisa, M. A.; Ljunggren, H. M.; Lodato, D. F.; Loenne, P. I.; Loginov, V.; Loizides, C.; Lopez, X.; López Torres, E.; Lowe, A.; Luettig, P.; Lunardon, M.; Luparello, G.; Luz, P. H. F. N. D.; Maevskaya, A.; Mager, M.; Mahajan, S.; Mahmood, S. M.; Maire, A.; Majka, R. D.; Malaev, M.; Maldonado Cervantes, I.; Malinina, L.; Mal'Kevich, D.; Malzacher, P.; Mamonov, A.; Manko, V.; Manso, F.; Manzari, V.; Marchisone, M.; Mareš, J.; Margagliotti, G. V.; Margotti, A.; Margutti, J.; Marín, A.; Markert, C.; Marquard, M.; Martin, N. A.; Martin Blanco, J.; Martinengo, P.; Martínez, M. I.; Martínez García, G.; Martinez Pedreira, M.; Martynov, Y.; Mas, A.; Masciocchi, S.; Masera, M.; Masoni, A.; Massacrier, L.; Mastroserio, A.; Masui, H.; Matyja, A.; Mayer, C.; Mazer, J.; Mazzoni, M. A.; McDonald, D.; Meddi, F.; Melikyan, Y.; Menchaca-Rocha, A.; Meninno, E.; Mercado Pérez, J.; Meres, M.; Miake, Y.; Mieskolainen, M. M.; Mikhaylov, K.; Milano, L.; Milosevic, J.; Minervini, L. M.; Mischke, A.; Mishra, A. N.; Miśkowiec, D.; Mitra, J.; Mitu, C. M.; Mohammadi, N.; Mohanty, B.; Molnar, L.; Montaño Zetina, L.; Montes, E.; Morando, M.; Moreira de Godoy, D. A.; Moretto, S.; Morreale, A.; Morsch, A.; Muccifora, V.; Mudnic, E.; Mühlheim, D.; Muhuri, S.; Mukherjee, M.; Mulligan, J. D.; Munhoz, M. G.; Murray, S.; Musa, L.; Musinsky, J.; Nandi, B. K.; Nania, R.; Nappi, E.; Naru, M. U.; Nattrass, C.; Nayak, K.; Nayak, T. K.; Nazarenko, S.; Nedosekin, A.; Nellen, L.; Ng, F.; Nicassio, M.; Niculescu, M.; Niedziela, J.; Nielsen, B. S.; Nikolaev, S.; Nikulin, S.; Nikulin, V.; Noferini, F.; Nomokonov, P.; Nooren, G.; Noris, J. C. C.; Norman, J.; Nyanin, A.; Nystrand, J.; Oeschler, H.; Oh, S.; Oh, S. K.; Ohlson, A.; Okatan, A.; Okubo, T.; Olah, L.; Oleniacz, J.; Oliveira da Silva, A. C.; Oliver, M. H.; Onderwaater, J.; Oppedisano, C.; Orava, R.; Ortiz Velasquez, A.; Oskarsson, A.; Otwinowski, J.; Oyama, K.; Ozdemir, M.; Pachmayer, Y.; Pagano, P.; Paić, G.; Pajares, C.; Pal, S. K.; Pan, J.; Pandey, A. K.; Pant, D.; Papcun, P.; Papikyan, V.; Pappalardo, G. S.; Pareek, P.; Park, W. J.; Parmar, S.; Passfeld, A.; Paticchio, V.; Patra, R. N.; Paul, B.; Peitzmann, T.; Pereira da Costa, H.; Pereira de Oliveira Filho, E.; Peresunko, D.; Pérez Lara, C. E.; Perez Lezama, E.; Peskov, V.; Pestov, Y.; Petráček, V.; Petrov, V.; Petrovici, M.; Petta, C.; Piano, S.; Pikna, M.; Pillot, P.; Pinazza, O.; Pinsky, L.; Piyarathna, D. B.; Płoskoń, M.; Planinic, M.; Pluta, J.; Pochybova, S.; Podesta-Lerma, P. L. M.; Poghosyan, M. G.; Polichtchouk, B.; Poljak, N.; Poonsawat, W.; Pop, A.; Porteboeuf-Houssais, S.; Porter, J.; Pospisil, J.; Prasad, S. K.; Preghenella, R.; Prino, F.; Pruneau, C. A.; Pshenichnov, I.; Puccio, M.; Puddu, G.; Pujahari, P.; Punin, V.; Putschke, J.; Qvigstad, H.; Rachevski, A.; Raha, S.; Rajput, S.; Rak, J.; Rakotozafindrabe, A.; Ramello, L.; Raniwala, R.; Raniwala, S.; Räsänen, S. S.; Rascanu, B. T.; Rathee, D.; Read, K. F.; Real, J. S.; Redlich, K.; Reed, R. J.; Rehman, A.; Reichelt, P.; Reidt, F.; Ren, X.; Renfordt, R.; Reolon, A. R.; Reshetin, A.; Rettig, F.; Revol, J.-P.; Reygers, K.; Riabov, V.; Ricci, R. A.; Richert, T.; Richter, M.; Riedler, P.; Riegler, W.; Riggi, F.; Ristea, C.; Rivetti, A.; Rocco, E.; Rodríguez Cahuantzi, M.; Rodriguez Manso, A.; Røed, K.; Rogochaya, E.; Rohr, D.; Röhrich, D.; Romita, R.; Ronchetti, F.; Ronflette, L.; Rosnet, P.; Rossi, A.; Roukoutakis, F.; Roy, A.; Roy, C.; Roy, P.; Rubio Montero, A. J.; Rui, R.; Russo, R.; Ryabinkin, E.; Ryabov, Y.; Rybicki, A.; Sadovsky, S.; Šafařík, K.; Sahlmuller, B.; Sahoo, P.; Sahoo, R.; Sahoo, S.; Sahu, P. K.; Saini, J.; Sakai, S.; Saleh, M. A.; Salgado, C. A.; Salzwedel, J.; Sambyal, S.; Samsonov, V.; Sanchez Castro, X.; Šándor, L.; Sandoval, A.; Sano, M.; Sarkar, D.; Scapparone, E.; Scarlassara, F.; Scharenberg, R. P.; Schiaua, C.; Schicker, R.; Schmidt, C.; Schmidt, H. R.; Schuchmann, S.; Schukraft, J.; Schulc, M.; Schuster, T.; Schutz, Y.; Schwarz, K.; Schweda, K.; Scioli, G.; Scomparin, E.; Scott, R.; Seger, J. E.; Sekiguchi, Y.; Sekihata, D.; Selyuzhenkov, I.; Senosi, K.; Seo, J.; Serradilla, E.; Sevcenco, A.; Shabanov, A.; Shabetai, A.; Shadura, O.; Shahoyan, R.; Shangaraev, A.; Sharma, A.; Sharma, M.; Sharma, M.; Sharma, N.; Shigaki, K.; Shtejer, K.; Sibiriak, Y.; Siddhanta, S.; Sielewicz, K. M.; Siemiarczuk, T.; Silvermyr, D.; Silvestre, C.; Simatovic, G.; Simonetti, G.; Singaraju, R.; Singh, R.; Singha, S.; Singhal, V.; Sinha, B. C.; Sinha, T.; Sitar, B.; Sitta, M.; Skaali, T. B.; Slupecki, M.; Smirnov, N.; Snellings, R. J. M.; Snellman, T. W.; Søgaard, C.; Soltz, R.; Song, J.; Song, M.; Song, Z.; Soramel, F.; Sorensen, S.; Spacek, M.; Spiriti, E.; Sputowska, I.; Spyropoulou-Stassinaki, M.; Srivastava, B. K.; Stachel, J.; Stan, I.; Stefanek, G.; Steinpreis, M.; Stenlund, E.; Steyn, G.; Stiller, J. H.; Stocco, D.; Strmen, P.; Suaide, A. A. P.; Sugitate, T.; Suire, C.; Suleymanov, M.; Sultanov, R.; Šumbera, M.; Symons, T. J. M.; Szabo, A.; Szanto de Toledo, A.; Szarka, I.; Szczepankiewicz, A.; Szymanski, M.; Takahashi, J.; Tambave, G. J.; Tanaka, N.; Tangaro, M. A.; Tapia Takaki, J. D.; Tarantola Peloni, A.; Tarhini, M.; Tariq, M.; Tarzila, M. G.; Tauro, A.; Tejeda Muñoz, G.; Telesca, A.; Terasaki, K.; Terrevoli, C.; Teyssier, B.; Thäder, J.; Thomas, D.; Tieulent, R.; Timmins, A. R.; Toia, A.; Trogolo, S.; Trubnikov, V.; Trzaska, W. H.; Tsuji, T.; Tumkin, A.; Turrisi, R.; Tveter, T. S.; Ullaland, K.; Uras, A.; Usai, G. L.; Utrobicic, A.; Vajzer, M.; Vala, M.; Valencia Palomo, L.; Vallero, S.; van der Maarel, J.; van Hoorne, J. W.; van Leeuwen, M.; Vanat, T.; Vande Vyvre, P.; Varga, D.; Vargas, A.; Vargyas, M.; Varma, R.; Vasileiou, M.; Vasiliev, A.; Vauthier, A.; Vechernin, V.; Veen, A. M.; Veldhoen, M.; Velure, A.; Venaruzzo, M.; Vercellin, E.; Vergara Limón, S.; Vernet, R.; Verweij, M.; Vickovic, L.; Viesti, G.; Viinikainen, J.; Vilakazi, Z.; Villalobos Baillie, O.; Vinogradov, A.; Vinogradov, L.; Vinogradov, Y.; Virgili, T.; Vislavicius, V.; Viyogi, Y. P.; Vodopyanov, A.; Völkl, M. A.; Voloshin, K.; Voloshin, S. A.; Volpe, G.; von Haller, B.; Vorobyev, I.; Vranic, D.; Vrláková, J.; Vulpescu, B.; Vyushin, A.; Wagner, B.; Wagner, J.; Wang, H.; Wang, M.; Wang, Y.; Watanabe, D.; Watanabe, Y.; Weber, M.; Weber, S. G.; Wessels, J. P.; Westerhoff, U.; Wiechula, J.; Wikne, J.; Wilde, M.; Wilk, G.; Wilkinson, J.; Williams, M. C. S.; Windelband, B.; Winn, M.; Yaldo, C. G.; Yang, H.; Yang, P.; Yano, S.; Yin, Z.; Yokoyama, H.; Yoo, I.-K.; Yurchenko, V.; Yushmanov, I.; Zaborowska, A.; Zaccolo, V.; Zaman, A.; Zampolli, C.; Zanoli, H. J. C.; Zaporozhets, S.; Zardoshti, N.; Zarochentsev, A.; Závada, P.; Zaviyalov, N.; Zbroszczyk, H.; Zgura, I. S.; Zhalov, M.; Zhang, H.; Zhang, X.; Zhang, Y.; Zhao, C.; Zhigareva, N.; Zhou, D.; Zhou, Y.; Zhou, Z.; Zhu, H.; Zhu, J.; Zhu, X.; Zichichi, A.; Zimmermann, A.; Zimmermann, M. B.; Zinovjev, G.; Zyzak, M.; Alice Collaboration

2016-02-01

We report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb-Pb collisions at √{sNN}=2.76 TeV as a function of collision centrality and the average transverse momentum of the pair kT. Three-dimensional sizes of the system (femtoscopic radii), as well as direction-averaged one-dimensional radii are extracted. The radii decrease with kT, following a power-law behavior. This is qualitatively consistent with expectations from a collectively expanding system, produced in hydrodynamic calculations. The radii also scale linearly with 1 /3. This behavior is compared to world data on femtoscopic radii in heavy-ion collisions. While the dependence is qualitatively similar to results at smaller √{sNN}, a decrease in the ratio Rout/Rside is seen, which is in qualitative agreement with a specific prediction from hydrodynamic models: a change from inside-out to outside-in freeze-out configuration. The results provide further evidence for the production of a collective, strongly coupled system in heavy-ion collisions at the CERN Large Hadron Collider.

Centrality dependence of pion freeze-out radii in Pb-Pb collisions at s N N = 2.76  TeV

DOE PAGES

Adam, J.; Adamová, D.; Aggarwal, M. M.; ...

2016-02-04

Here, we report on the measurement of freeze-out radii for pairs of identical-charge pions measured in Pb-Pb collisions at √s NN = 2.76 TeV as a function of collision centrality and the average transverse momentum of the pair k T. Three-dimensional sizes of the system (femtoscopic radii), as well as direction-averaged one-dimensional radii are extracted. The radii decrease with k T, following a power-law behavior. This is qualitatively consistent with expectations from a collectively expanding system, produced in hydrodynamic calculations. The radii also scale linearly with < dN ch/d η > 1/3. We compare this behavior to world data onmore » femtoscopic radii in heavy-ion collisions. While the dependence is qualitatively similar to results at smaller √s NN, a decrease in the ratio R out/R side is seen, which is in qualitative agreement with a specific prediction from hydrodynamic models: a change from inside-out to outside-in freeze-out configuration. Furthermore, these results provide further evidence for the production of a collective, strongly coupled system in heavy-ion collisions at the CERN Large Hadron Collider.« less

Measuring B{sup {+-}}{yields}{tau}{sup {+-}}{nu} and B{sub c}{sup {+-}}{yields}{tau}{sup {+-}}{nu} at the Z peak

DOE Office of Scientific and Technical Information (OSTI.GOV)

Akeroyd, A. G.; Chen, C.H.; National Center for Theoretical Sciences, Taiwan

2008-06-01

The measurement of B{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} at the B factories provides important constraints on the parameter tan{beta}/m{sub H{sup {+-}}} in the context of models with two Higgs doublets. Limits on this decay from e{sup +}e{sup -} collisions at the Z peak were sensitive to the sum of B{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} and B{sub c}{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}}. Because of the possibly sizeable contribution from B{sub c}{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} we suggest that a signal for this combination might be observed if the CERN LEP L3 Collaboration used its total data of {approx}3.6x10{sup 6} hadronic decays of the Z boson.more » Moreover, we point out that a future linear collider operating at the Z peak (Giga Z option) could constrain tan{beta}/m{sub H{sup {+-}}} from the sum of these processes with a precision comparable to that anticipated at proposed high luminosity B factories from B{sup {+-}}{yields}{tau}{sup {+-}}{nu}{sub {tau}} alone.« less

New vertical cryostat for the high field superconducting magnet test station at CERN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Vande Craen, A.; Atieh, S.; Bajko, M.

2014-01-29

In the framework of the R and D program for new superconducting magnets for the Large Hadron Collider accelerator upgrades, CERN is building a new vertical test station to test high field superconducting magnets of unprecedented large size. This facility will allow testing of magnets by vertical insertion in a pressurized liquid helium bath, cooled to a controlled temperature between 4.2 K and 1.9 K. The dimensions of the cryostat will allow testing magnets of up to 2.5 m in length with a maximum diameter of 1.5 m and a mass of 15 tons. To allow for a faster insertionmore » and removal of the magnets and reducing the risk of helium leaks, all cryogenics supply lines are foreseen to remain permanently connected to the cryostat. A specifically designed 100 W heat exchanger is integrated in the cryostat helium vessel for a controlled cooling of the magnet from 4.2 K down to 1.9 K in a 3 m{sup 3} helium bath. This paper describes the cryostat and its main functions, focusing on features specifically developed for this project. The status of the construction and the plans for assembly and installation at CERN are also presented.« less

R&D status of linear collider technology at KEK

NASA Astrophysics Data System (ADS)

Urakawa, Junji

1992-02-01

This paper gives an outline of the Japan Linear Collider (JLC) project, especially JLC-I. The status of the various R&D works is particularly presented for the following topics: (1) electron and positron sources, (2) S-band injector linacs, (3) damping rings, (4) high power klystrons and accelerating structures, (5) the final focus system. Finally, the status of the construction and design studies for the Accelerator Test Facility (ATF) is summarized.

Detectors for Linear Colliders: Physics Requirements and Experimental Conditions (1/4)

ScienceCinema

Battaglia, Marco

2018-01-12

How is the anticipated physics program of a future e+e- collider shaping the R&D; for new detectors in collider particle physics ? This presentation will review the main physics requirements and experimental conditions comparing to LHC and LEP. In particular, I shall discuss how e+e- experimentation is expected to change moving from LEP-2 up to multi-TeV energies.

ATLAS TDAQ System Administration: Master of Puppets

NASA Astrophysics Data System (ADS)

Ballestrero, S.; Brasolin, F.; Fazio, D.; Gament, C.; Lee, C. J.; Scannicchio, D. A.; Twomey, M. S.

2017-10-01

Within the ATLAS detector, the Trigger and Data Acquisition system is responsible for the online processing of data streamed from the detector during collisions at the Large Hadron Collider at CERN. The online farm is comprised of ∼4000 servers processing the data read out from ∼100 million detector channels through multiple trigger levels. The configurtion of these servers is not an easy task, especially since the detector itself is made up of multiple different sub-detectors, each with their own particular requirements. The previous method of configuring these servers, using Quattor and a hierarchical scripts system was cumbersome and restrictive. A better, unified system was therefore required to simplify the tasks of the TDAQ Systems Administrators, for both the local and net-booted systems, and to be able to fulfil the requirements of TDAQ, Detector Control Systems and the sub-detectors groups. Various configuration management systems were evaluated, though in the end, Puppet was chosen as the application of choice and was the first such implementation at CERN.

PREFACE: International Workshop on Discovery Physics at the LHC (Kruger2014)

NASA Astrophysics Data System (ADS)

Cleymans, Jean

2015-06-01

The third biannual conference on 'Discovery Physics at the LHC' was held on December 1-6 2014 at the Kruger Gate Hotel in South Africa. Over 100 participants attended from Austria, Australia, Belgium, Brazil, Canada, China, the Czech Republic, France, Germany, Italy, the Netherlands, Norway, Poland, South Africa, Switzerland, the UK and the USA. The latest results from the Large Hadron Collider as well the latest theoretical insights were presented. With the majestic Kruger National Park in the background this led to a very stimulating conference with many exchanges taking place. The proceedings reflect the high level of the conference. The financial contributions from the SA-CERN programme, the UCT-CERN Research Centre, the University of Johannesburg, the University of the Witwatersrand and iThemba L.A.B.S. are gratefully acknowledged. Local Organizing Committee: Z. Buthelezi J. Cleymans (chair) S. H. Connell A. S. Cornell T. Dietel S. Förtsch N. Haasbroek A. Hamilton W. A. Horowitz B. Mellado Z. Z. Vilakazi S. Yacoob

Embedded fiber Bragg grating sensors for true temperature monitoring in Nb3Sn superconducting magnets for high energy physics

NASA Astrophysics Data System (ADS)

Chiuchiolo, A.; Bajas, H.; Bajko, M.; Consales, M.; Giordano, M.; Perez, J. C.; Cusano, A.

2016-05-01

The luminosity upgrade of the Large Hadron Collider (HL-LHC) planned at the European Organization for Nuclear Research (CERN) requires the development of a new generation of superconducting magnets based on Nb3Sn technology. The instrumentation required for the racetrack coils needs the development of reliable sensing systems able to monitor the magnet thermo-mechanical behavior during its service life, from the coil fabrication to the magnet operation. With this purpose, Fiber Bragg Grating (FBG) sensors have been embedded in the coils of the Short Model Coil (SMC) magnet fabricated at CERN. The FBG sensitivity to both temperature and strain required the development of a solution able to separate mechanical and temperature effects. This work presents for the first time a feasibility study devoted to the implementation of an embedded FBG sensor for the measurement of the "true" temperature in the impregnated Nb3Sn coil during the fabrication process.

Construction and test of a fine-grained liquid argon preshower prototype

NASA Astrophysics Data System (ADS)

Davis, R. A.; Gingrich, D. M.; Pinfold, J. L.; Rodning, N. L.; Boos, E.; Zhautykov, B. O.; Aubert, B.; Bazan, A.; Beaugiraud, B.; Boniface, J.; Colas, J.; Eynard, G.; Jezequel, S.; Leflour, T.; Linossier, O.; Nicoleau, S.; Rival, F.; Sauvage, G.; Thion, J.; VanDenPlas, D.; Wingerter-Seez, I.; Zitoun, R.; Zolnierowski, Y. P.; Chmeissani, M.; Fernandez, E.; Garrido, Ll.; Martinez, M.; Padilla, C.; Gordon, H. A.; Radeka, V.; Rahm, D.; Stephani, D.; Baisin, L.; Berset, J. C.; Chevalley, J. L.; Gianotti, F.; Gildemeister, O.; Marin, C. P.; Nessi, M.; Poggioli, L.; Richter, W.; Vuillemin, V.; Baze, J. M.; Gosset, L.; Lavocat, P.; Lottin, J. P.; Mansoulié, B.; Meyer, J. P.; Renardy, J. F.; Schwindling, J.; Teiger, J.; Collot, J.; de Saintignon, P.; Dzahini, D.; Hostachy, J. Y.; Hoummada, A.; Laborie, G.; Mahout, G.; Hervas, L.; Chekhtman, A.; Cousinou, M. C.; Dargent, P.; Dinkespiller, B.; Etienne, F.; Fassnacht, P.; Fouchez, D.; Martin, L.; Miotto, A.; Monnier, E.; Nagy, E.; Olivetto, C.; Tisserant, S.; Battistoni, G.; Camin, D. V.; Cavalli, D.; Costa, G.; Cozzi, L.; Fedyakin, N.; Ferrari, A.; Mandelli, L.; Mazzanti, M.; Perini, L.; Resconi, S.; Sala, P.; Beaudoin, G.; Depommier, P.; León-Florián, E.; Leroy, C.; Roy, P.; Augé, E.; Chase, R.; Chollet, J. C.; de La Taille, C.; Fayard, L.; Fournier, D.; Hrisoho, A.; Merkel, B.; Noppe, J. M.; Parrour, G.; Pétroff, P.; Schaffer, A.; Seguin-Moreau, N.; Serin, L.; Tisserand, V.; Vichou, I.; Canton, B.; David, J.; Genat, J. F.; Imbault, D.; Le Dortz, O.; Savoy-Navarro, A.; Schwemling, P.; Eek, L. O.; Lund-Jensen, B.; Söderqvist, J.; Lefebvre, M.; Robertson, S.; RD3 Collaboration

1997-02-01

A separate liquid argon preshower detector consisting of two layers featuring a fine granularity of 2.5 × 10 -3 was studied by the RD3 collaboration. A prototype covering approximately 0.8 in pseudo-rapidity and 9° in azimuth was built and tested at CERN in July 94. CMOS and GaAs VLSI preamplifiers were designed and tested for this occasion. The combined response of this detector and an accordion electromagnetic calorimeter prototype to muons, electrons and photons is presented. For minimum ionizing tracks a signal-to-noise ratio of 4.5 per preshower layer was measured. Above 150 GeV the space resolution for electrons is better than 250 μm in both directions. The precision on the electromagnetic shower direction, determined together with the calorimeter, is better than 4 mrad above 50 GeV. It is concluded that the preshower detector would adequately fulfil its role for future operation at CERN Large Hadron Collider.

The CMS experiment at the CERN LHC

NASA Astrophysics Data System (ADS)

CMS Collaboration; Chatrchyan, S.; Hmayakyan, G.; Khachatryan, V.; Sirunyan, A. M.; Adam, W.; Bauer, T.; Bergauer, T.; Bergauer, H.; Dragicevic, M.; Erö, J.; Friedl, M.; Frühwirth, R.; Ghete, V. M.; Glaser, P.; Hartl, C.; Hoermann, N.; Hrubec, J.; Hänsel, S.; Jeitler, M.; Kastner, K.; Krammer, M.; Magrans de Abril, I.; Markytan, M.; Mikulec, I.; Neuherz, B.; Nöbauer, T.; Oberegger, M.; Padrta, M.; Pernicka, M.; Porth, P.; Rohringer, H.; Schmid, S.; Schreiner, T.; Stark, R.; Steininger, H.; Strauss, J.; Taurok, A.; Uhl, D.; Waltenberger, W.; Walzel, G.; Widl, E.; Wulz, C.-E.; Petrov, V.; Prosolovich, V.; Chekhovsky, V.; Dvornikov, O.; Emeliantchik, I.; Litomin, A.; Makarenko, V.; Marfin, I.; Mossolov, V.; Shumeiko, N.; Solin, A.; Stefanovitch, R.; Suarez Gonzalez, J.; Tikhonov, A.; Fedorov, A.; Korzhik, M.; Missevitch, O.; Zuyeuski, R.; Beaumont, W.; Cardaci, M.; DeLanghe, E.; DeWolf, E. A.; Delmeire, E.; Ochesanu, S.; Tasevsky, M.; Van Mechelen, P.; D'Hondt, J.; DeWeirdt, S.; Devroede, O.; Goorens, R.; Hannaert, S.; Heyninck, J.; Maes, J.; Mozer, M. U.; Tavernier, S.; Van Doninck, W.; Van Lancker, L.; Van Mulders, P.; Villella, I.; Wastiels, C.; Yu, C.; Bouhali, O.; Charaf, O.; Clerbaux, B.; DeHarenne, P.; DeLentdecker, G.; Dewulf, J. P.; Elgammal, S.; Gindroz, R.; Hammad, G. H.; Mahmoud, T.; Neukermans, L.; Pins, M.; Pins, R.; Rugovac, S.; Stefanescu, J.; Sundararajan, V.; Vander Velde, C.; Vanlaer, P.; Wickens, J.; Tytgat, M.; Assouak, S.; Bonnet, J. L.; Bruno, G.; Caudron, J.; DeCallatay, B.; DeFavereau DeJeneret, J.; DeVisscher, S.; Demin, P.; Favart, D.; Felix, C.; Florins, B.; Forton, E.; Giammanco, A.; Grégoire, G.; Jonckman, M.; Kcira, D.; Keutgen, T.; Lemaitre, V.; Michotte, D.; Militaru, O.; Ovyn, S.; Pierzchala, T.; Piotrzkowski, K.; Roberfroid, V.; Rouby, X.; Schul, N.; Van der Aa, O.; Beliy, N.; Daubie, E.; Herquet, P.; Alves, G.; Pol, M. E.; Souza, M. H. G.; Vaz, M.; DeJesus Damiao, D.; Oguri, V.; Santoro, A.; Sznajder, A.; DeMoraes Gregores, E.; Iope, R. L.; Novaes, S. F.; Tomei, T.; Anguelov, T.; Antchev, G.; Atanasov, I.; Damgov, J.; Darmenov, N.; Dimitrov, L.; Genchev, V.; Iaydjiev, P.; Marinov, A.; Piperov, S.; Stoykova, S.; Sultanov, G.; Trayanov, R.; Vankov, I.; Cheshkov, C.; Dimitrov, A.; Dyulendarova, M.; Glushkov, I.; Kozhuharov, V.; Litov, L.; Makariev, M.; Marinova, E.; Markov, S.; Mateev, M.; Nasteva, I.; Pavlov, B.; Petev, P.; Petkov, P.; Spassov, V.; Toteva, Z.; Velev, V.; Verguilov, V.; Bian, J. G.; Chen, G. M.; Chen, H. S.; Chen, M.; Jiang, C. H.; Liu, B.; Shen, X. Y.; Sun, H. S.; Tao, J.; Wang, J.; Yang, M.; Zhang, Z.; Zhao, W. R.; Zhuang, H. L.; Ban, Y.; Cai, J.; Ge, Y. C.; Liu, S.; Liu, H. T.; Liu, L.; Qian, S. J.; Wang, Q.; Xue, Z. H.; Yang, Z. C.; Ye, Y. L.; Ying, J.; Li, P. J.; Liao, J.; Xue, Z. L.; Yan, D. S.; Yuan, H.; Carrillo Montoya, C. A.; Sanabria, J. C.; Godinovic, N.; Puljak, I.; Soric, I.; Antunovic, Z.; Dzelalija, M.; Marasovic, K.; Brigljevic, V.; Kadija, K.; Morovic, S.; Fereos, R.; Nicolaou, C.; Papadakis, A.; Ptochos, F.; Razis, P. A.; Tsiakkouri, D.; Zinonos, Z.; Hektor, A.; Kadastik, M.; Kannike, K.; Lippmaa, E.; Müntel, M.; Raidal, M.; Rebane, L.; Aarnio, P. A.; Anttila, E.; Banzuzi, K.; Bulteau, P.; Czellar, S.; Eiden, N.; Eklund, C.; Engstrom, P.; Heikkinen, A.; Honkanen, A.; Härkönen, J.; Karimäki, V.; Katajisto, H. M.; Kinnunen, R.; Klem, J.; Kortesmaa, J.; Kotamäki, M.; Kuronen, A.; Lampén, T.; Lassila-Perini, K.; Lefébure, V.; Lehti, S.; Lindén, T.; Luukka, P. R.; Michal, S.; Moura Brigido, F.; Mäenpää, T.; Nyman, T.; Nystén, J.; Pietarinen, E.; Skog, K.; Tammi, K.; Tuominen, E.; Tuominiemi, J.; Ungaro, D.; Vanhala, T. P.; Wendland, L.; Williams, C.; Iskanius, M.; Korpela, A.; Polese, G.; Tuuva, T.; Bassompierre, G.; Bazan, A.; David, P. Y.; Ditta, J.; Drobychev, G.; Fouque, N.; Guillaud, J. P.; Hermel, V.; Karneyeu, A.; LeFlour, T.; Lieunard, S.; Maire, M.; Mendiburu, P.; Nedelec, P.; Peigneux, J. P.; Schneegans, M.; Sillou, D.; Vialle, J. P.; Anfreville, M.; Bard, J. P.; Besson, P.; Bougamont, E.; Boyer, M.; Bredy, P.; Chipaux, R.; Dejardin, M.; Denegri, D.; Descamps, J.; Fabbro, B.; Faure, J. L.; Ganjour, S.; Gentit, F. X.; Givernaud, A.; Gras, P.; Hamel de Monchenault, G.; Jarry, P.; Jeanney, C.; Kircher, F.; Lemaire, M. C.; Lemoigne, Y.; Levesy, B.; Locci, E.; Lottin, J. P.; Mandjavidze, I.; Mur, M.; Pansart, J. P.; Payn, A.; Rander, J.; Reymond, J. M.; Rolquin, J.; Rondeaux, F.; Rosowsky, A.; Rousse, J. Y. A.; Sun, Z. H.; Tartas, J.; Van Lysebetten, A.; Venault, P.; Verrecchia, P.; Anduze, M.; Badier, J.; Baffioni, S.; Bercher, M.; Bernet, C.; Berthon, U.; Bourotte, J.; Busata, A.; Busson, P.; Cerutti, M.; Chamont, D.; Charlot, C.; Collard, C.; Debraine, A.; Decotigny, D.; Dobrzynski, L.; Ferreira, O.; Geerebaert, Y.; Gilly, J.; Gregory, C.; Guevara Riveros, L.; Haguenauer, M.; Karar, A.; Koblitz, B.; Lecouturier, D.; Mathieu, A.; Milleret, G.; Miné, P.; Paganini, P.; Poilleux, P.; Pukhaeva, N.; Regnault, N.; Romanteau, T.; Semeniouk, I.; Sirois, Y.; Thiebaux, C.; Vanel, J. C.; Zabi, A.; Agram, J. L.; Albert, A.; Anckenmann, L.; Andrea, J.; Anstotz, F.; Bergdolt, A. M.; Berst, J. D.; Blaes, R.; Bloch, D.; Brom, J. M.; Cailleret, J.; Charles, F.; Christophel, E.; Claus, G.; Coffin, J.; Colledani, C.; Croix, J.; Dangelser, E.; Dick, N.; Didierjean, F.; Drouhin, F.; Dulinski, W.; Ernenwein, J. P.; Fang, R.; Fontaine, J. C.; Gaudiot, G.; Geist, W.; Gelé, D.; Goeltzenlichter, T.; Goerlach, U.; Graehling, P.; Gross, L.; Hu, C. Guo; Helleboid, J. M.; Henkes, T.; Hoffer, M.; Hoffmann, C.; Hosselet, J.; Houchu, L.; Hu, Y.; Huss, D.; Illinger, C.; Jeanneau, F.; Juillot, P.; Kachelhoffer, T.; Kapp, M. R.; Kettunen, H.; Lakehal Ayat, L.; LeBihan, A. C.; Lounis, A.; Maazouzi, C.; Mack, V.; Majewski, P.; Mangeol, D.; Michel, J.; Moreau, S.; Olivetto, C.; Pallarès, A.; Patois, Y.; Pralavorio, P.; Racca, C.; Riahi, Y.; Ripp-Baudot, I.; Schmitt, P.; Schunck, J. P.; Schuster, G.; Schwaller, B.; Sigward, M. H.; Sohler, J. L.; Speck, J.; Strub, R.; Todorov, T.; Turchetta, R.; Van Hove, P.; Vintache, D.; Zghiche, A.; Ageron, M.; Augustin, J. E.; Baty, C.; Baulieu, G.; Bedjidian, M.; Blaha, J.; Bonnevaux, A.; Boudoul, G.; Brunet, P.; Chabanat, E.; Chabert, E. C.; Chierici, R.; Chorowicz, V.; Combaret, C.; Contardo, D.; Della Negra, R.; Depasse, P.; Drapier, O.; Dupanloup, M.; Dupasquier, T.; El Mamouni, H.; Estre, N.; Fay, J.; Gascon, S.; Giraud, N.; Girerd, C.; Guillot, G.; Haroutunian, R.; Ille, B.; Lethuillier, M.; Lumb, N.; Martin, C.; Mathez, H.; Maurelli, G.; Muanza, S.; Pangaud, P.; Perries, S.; Ravat, O.; Schibler, E.; Schirra, F.; Smadja, G.; Tissot, S.; Trocme, B.; Vanzetto, S.; Walder, J. P.; Bagaturia, Y.; Mjavia, D.; Mzhavia, A.; Tsamalaidze, Z.; Roinishvili, V.; Adolphi, R.; Anagnostou, G.; Brauer, R.; Braunschweig, W.; Esser, H.; Feld, L.; Karpinski, W.; Khomich, A.; Klein, K.; Kukulies, C.; Lübelsmeyer, K.; Olzem, J.; Ostaptchouk, A.; Pandoulas, D.; Pierschel, G.; Raupach, F.; Schael, S.; Schultz von Dratzig, A.; Schwering, G.; Siedling, R.; Thomas, M.; Weber, M.; Wittmer, B.; Wlochal, M.; Adamczyk, F.; Adolf, A.; Altenhöfer, G.; Bechstein, S.; Bethke, S.; Biallass, P.; Biebel, O.; Bontenackels, M.; Bosseler, K.; Böhm, A.; Erdmann, M.; Faissner, H.; Fehr, B.; Fesefeldt, H.; Fetchenhauer, G.; Frangenheim, J.; Frohn, J. H.; Grooten, J.; Hebbeker, T.; Hermann, S.; Hermens, E.; Hilgers, G.; Hoepfner, K.; Hof, C.; Jacobi, E.; Kappler, S.; Kirsch, M.; Kreuzer, P.; Kupper, R.; Lampe, H. R.; Lanske, D.; Mameghani, R.; Meyer, A.; Meyer, S.; Moers, T.; Müller, E.; Pahlke, R.; Philipps, B.; Rein, D.; Reithler, H.; Reuter, W.; Rütten, P.; Schulz, S.; Schwarthoff, H.; Sobek, W.; Sowa, M.; Stapelberg, T.; Szczesny, H.; Teykal, H.; Teyssier, D.; Tomme, H.; Tomme, W.; Tonutti, M.; Tsigenov, O.; Tutas, J.; Vandenhirtz, J.; Wagner, H.; Wegner, M.; Zeidler, C.; Beissel, F.; Davids, M.; Duda, M.; Flügge, G.; Giffels, M.; Hermanns, T.; Heydhausen, D.; Kalinin, S.; Kasselmann, S.; Kaussen, G.; Kress, T.; Linn, A.; Nowack, A.; Perchalla, L.; Poettgens, M.; Pooth, O.; Sauerland, P.; Stahl, A.; Tornier, D.; Zoeller, M. H.; Behrens, U.; Borras, K.; Flossdorf, A.; Hatton, D.; Hegner, B.; Kasemann, M.; Mankel, R.; Meyer, A.; Mnich, J.; Rosemann, C.; Youngman, C.; Zeuner, W. D.; Bechtel, F.; Buhmann, P.; Butz, E.; Flucke, G.; Hamdorf, R. H.; Holm, U.; Klanner, R.; Pein, U.; Schirm, N.; Schleper, P.; Steinbrück, G.; Van Staa, R.; Wolf, R.; Atz, B.; Barvich, T.; Blüm, P.; Boegelspacher, F.; Bol, H.; Chen, Z. Y.; Chowdhury, S.; DeBoer, W.; Dehm, P.; Dirkes, G.; Fahrer, M.; Felzmann, U.; Frey, M.; Furgeri, A.; Gregoriev, E.; Hartmann, F.; Hauler, F.; Heier, S.; Kärcher, K.; Ledermann, B.; Mueller, S.; Müller, Th; Neuberger, D.; Piasecki, C.; Quast, G.; Rabbertz, K.; Sabellek, A.; Scheurer, A.; Schilling, F. P.; Simonis, H. J.; Skiba, A.; Steck, P.; Theel, A.; Thümmel, W. H.; Trunov, A.; Vest, A.; Weiler, T.; Weiser, C.; Weseler, S.; Zhukov, V.; Barone, M.; Daskalakis, G.; Dimitriou, N.; Fanourakis, G.; Filippidis, C.; Geralis, T.; Kalfas, C.; Karafasoulis, K.; Koimas, A.; Kyriakis, A.; Kyriazopoulou, S.; Loukas, D.; Markou, A.; Markou, C.; Mastroyiannopoulos, N.; Mavrommatis, C.; Mousa, J.; Papadakis, I.; Petrakou, E.; Siotis, I.; Theofilatos, K.; Tzamarias, S.; Vayaki, A.; Vermisoglou, G.; Zachariadou, A.; Gouskos, L.; Karapostoli, G.; Katsas, P.; Panagiotou, A.; Papadimitropoulos, C.; Aslanoglou, X.; Evangelou, I.; Kokkas, P.; Manthos, N.; Papadopoulos, I.; Triantis, F. A.; Bencze, G.; Boldizsar, L.; Debreczeni, G.; Hajdu, C.; Hidas, P.; Horvath, D.; Kovesarki, P.; Laszlo, A.; Odor, G.; Patay, G.; Sikler, F.; Veres, G.; Vesztergombi, G.; Zalan, P.; Fenyvesi, A.; Imrek, J.; Molnar, J.; Novak, D.; Palinkas, J.; Szekely, G.; Beni, N.; Kapusi, A.; Marian, G.; Radics, B.; Raics, P.; Szabo, Z.; Szillasi, Z.; Trocsanyi, Z. L.; Zilizi, G.; Bawa, H. S.; Beri, S. B.; Bhandari, V.; Bhatnagar, V.; Kaur, M.; Kohli, J. M.; Kumar, A.; Singh, B.; Singh, J. B.; Arora, S.; Bhattacharya, S.; Chatterji, S.; Chauhan, S.; Choudhary, B. C.; Gupta, P.; Jha, M.; Ranjan, K.; Shivpuri, R. K.; Srivastava, A. K.; Choudhury, R. K.; Dutta, D.; Ghodgaonkar, M.; Kailas, S.; Kataria, S. K.; Mohanty, A. K.; Pant, L. M.; Shukla, P.; Topkar, A.; Aziz, T.; Banerjee, Sunanda; Bose, S.; Chendvankar, S.; Deshpande, P. V.; Guchait, M.; Gurtu, A.; Maity, M.; Majumder, G.; Mazumdar, K.; Nayak, A.; Patil, M. R.; Sharma, S.; Sudhakar, K.; Acharya, B. S.; Banerjee, Sudeshna; Bheesette, S.; Dugad, S.; Kalmani, S. D.; Lakkireddi, V. R.; Mondal, N. K.; Panyam, N.; Verma, P.; Arfaei, H.; Hashemi, M.; Najafabadi, M. Mohammadi; Moshaii, A.; Paktinat Mehdiabadi, S.; Felcini, M.; Grunewald, M.; Abadjiev, K.; Abbrescia, M.; Barbone, L.; Cariola, P.; Chiumarulo, F.; Clemente, A.; Colaleo, A.; Creanza, D.; DeFilippis, N.; DePalma, M.; DeRobertis, G.; Donvito, G.; Ferorelli, R.; Fiore, L.; Franco, M.; Giordano, D.; Guida, R.; Iaselli, G.; Lacalamita, N.; Loddo, F.; Maggi, G.; Maggi, M.; Manna, N.; Marangelli, B.; Mennea, M. S.; My, S.; Natali, S.; Nuzzo, S.; Papagni, G.; Pinto, C.; Pompili, A.; Pugliese, G.; Ranieri, A.; Romano, F.; Roselli, G.; Sala, G.; Selvaggi, G.; Silvestris, L.; Tempesta, P.; Trentadue, R.; Tupputi, S.; Zito, G.; Abbiendi, G.; Bacchi, W.; Battilana, C.; Benvenuti, A. C.; Boldini, M.; Bonacorsi, D.; Braibant-Giacomelli, S.; Cafaro, V. D.; Capiluppi, P.; Castro, A.; Cavallo, F. R.; Ciocca, C.; Codispoti, G.; Cuffiani, M.; D'Antone, I.; Dallavalle, G. M.; Fabbri, F.; Fanfani, A.; Finelli, S.; Giacomelli, P.; Giordano, V.; Giunta, M.; Grandi, C.; Guerzoni, M.; Guiducci, L.; Marcellini, S.; Masetti, G.; Montanari, A.; Navarria, F. L.; Odorici, F.; Paolucci, A.; Pellegrini, G.; Perrotta, A.; Rossi, A. M.; Rovelli, T.; Siroli, G. P.; Torromeo, G.; Travaglini, R.; Veronese, G. P.; Albergo, S.; Chiorboli, M.; Costa, S.; Galanti, M.; Gatto Rotondo, G.; Giudice, N.; Guardone, N.; Noto, F.; Potenza, R.; Saizu, M. A.; Salemi, G.; Sutera, C.; Tricomi, A.; Tuve, C.; Bellucci, L.; Brianzi, M.; Broccolo, G.; Catacchini, E.; Ciulli, V.; Civinini, C.; D'Alessandro, R.; Focardi, E.; Frosali, S.; Genta, C.; Landi, G.; Lenzi, P.; Macchiolo, A.; Maletta, F.; Manolescu, F.; Marchettini, C.; Masetti, L.; Mersi, S.; Meschini, M.; Minelli, C.; Paoletti, S.; Parrini, G.; Scarlini, E.; Sguazzoni, G.; Benussi, L.; Bertani, M.; Bianco, S.; Caponero, M.; Colonna, D.; Daniello, L.; Fabbri, F.; Felli, F.; Giardoni, M.; La Monaca, A.; Ortenzi, B.; Pallotta, M.; Paolozzi, A.; Paris, C.; Passamonti, L.; Pierluigi, D.; Ponzio, B.; Pucci, C.; Russo, A.; Saviano, G.; Fabbricatore, P.; Farinon, S.; Greco, M.; Musenich, R.; Badoer, S.; Berti, L.; Biasotto, M.; Fantinel, S.; Frizziero, E.; Gastaldi, U.; Gulmini, M.; Lelli, F.; Maron, G.; Squizzato, S.; Toniolo, N.; Traldi, S.; Banfi, S.; Bertoni, R.; Bonesini, M.; Carbone, L.; Cerati, G. B.; Chignoli, F.; D'Angelo, P.; DeMin, A.; Dini, P.; Farina, F. M.; Ferri, F.; Govoni, P.; Magni, S.; Malberti, M.; Malvezzi, S.; Mazza, R.; Menasce, D.; Miccio, V.; Moroni, L.; Negri, P.; Paganoni, M.; Pedrini, D.; Pullia, A.; Ragazzi, S.; Redaelli, N.; Rovere, M.; Sala, L.; Sala, S.; Salerno, R.; Tabarelli de Fatis, T.; Tancini, V.; Taroni, S.; Boiano, A.; Cassese, F.; Cassese, C.; Cimmino, A.; D'Aquino, B.; Lista, L.; Lomidze, D.; Noli, P.; Paolucci, P.; Passeggio, G.; Piccolo, D.; Roscilli, L.; Sciacca, C.; Vanzanella, A.; Azzi, P.; Bacchetta, N.; Barcellan, L.; Bellato, M.; Benettoni, M.; Bisello, D.; Borsato, E.; Candelori, A.; Carlin, R.; Castellani, L.; Checchia, P.; Ciano, L.; Colombo, A.; Conti, E.; Da Rold, M.; Dal Corso, F.; DeGiorgi, M.; DeMattia, M.; Dorigo, T.; Dosselli, U.; Fanin, C.; Galet, G.; Gasparini, F.; Gasparini, U.; Giraldo, A.; Giubilato, P.; Gonella, F.; Gresele, A.; Griggio, A.; Guaita, P.; Kaminskiy, A.; Karaevskii, S.; Khomenkov, V.; Kostylev, D.; Lacaprara, S.; Lazzizzera, I.; Lippi, I.; Loreti, M.; Margoni, M.; Martinelli, R.; Mattiazzo, S.; Mazzucato, M.; Meneguzzo, A. T.; Modenese, L.; Montecassiano, F.; Neviani, A.; Nigro, M.; Paccagnella, A.; Pantano, D.; Parenti, A.; Passaseo, M.; Pedrotta, R.; Pegoraro, M.; Rampazzo, G.; Reznikov, S.; Ronchese, P.; Sancho Daponte, A.; Sartori, P.; Stavitskiy, I.; Tessaro, M.; Torassa, E.; Triossi, A.; Vanini, S.; Ventura, S.; Ventura, L.; Verlato, M.; Zago, M.; Zatti, F.; Zotto, P.; Zumerle, G.; Baesso, P.; Belli, G.; Berzano, U.; Bricola, S.; Grelli, A.; Musitelli, G.; Nardò, R.; Necchi, M. M.; Pagano, D.; Ratti, S. P.; Riccardi, C.; Torre, P.; Vicini, A.; Vitulo, P.; Viviani, C.; Aisa, D.; Aisa, S.; Ambroglini, F.; Angarano, M. M.; Babucci, E.; Benedetti, D.; Biasini, M.; Bilei, G. M.; Bizzaglia, S.; Brunetti, M. T.; Caponeri, B.; Checcucci, B.; Covarelli, R.; Dinu, N.; Fanò, L.; Farnesini, L.; Giorgi, M.; Lariccia, P.; Mantovani, G.; Moscatelli, F.; Passeri, D.; Piluso, A.; Placidi, P.; Postolache, V.; Santinelli, R.; Santocchia, A.; Servoli, L.; Spiga, D.; Azzurri, P.; Bagliesi, G.; Balestri, G.; Basti, A.; Bellazzini, R.; Benucci, L.; Bernardini, J.; Berretta, L.; Bianucci, S.; Boccali, T.; Bocci, A.; Borrello, L.; Bosi, F.; Bracci, F.; Brez, A.; Calzolari, F.; Castaldi, R.; Cazzola, U.; Ceccanti, M.; Cecchi, R.; Cerri, C.; Cucoanes, A. S.; Dell'Orso, R.; Dobur, D.; Dutta, S.; Fiori, F.; Foà, L.; Gaggelli, A.; Gennai, S.; Giassi, A.; Giusti, S.; Kartashov, D.; Kraan, A.; Latronico, L.; Ligabue, F.; Linari, S.; Lomtadze, T.; Lungu, G. A.; Magazzu, G.; Mammini, P.; Mariani, F.; Martinelli, G.; Massa, M.; Messineo, A.; Moggi, A.; Palla, F.; Palmonari, F.; Petragnani, G.; Petrucciani, G.; Profeti, A.; Raffaelli, F.; Rizzi, D.; Sanguinetti, G.; Sarkar, S.; Segneri, G.; Sentenac, D.; Serban, A. T.; Slav, A.; Spagnolo, P.; Spandre, G.; Tenchini, R.; Tolaini, S.; Tonelli, G.; Venturi, A.; Verdini, P. G.; Vos, M.; Zaccarelli, L.; Baccaro, S.; Barone, L.; Bartoloni, A.; Borgia, B.; Capradossi, G.; Cavallari, F.; Cecilia, A.; D'Angelo, D.; Dafinei, I.; DelRe, D.; Di Marco, E.; Diemoz, M.; Ferrara, G.; Gargiulo, C.; Guerra, S.; Iannone, M.; Longo, E.; Montecchi, M.; Nuccetelli, M.; Organtini, G.; Palma, A.; Paramatti, R.; Pellegrino, F.; Rahatlou, S.; Rovelli, C.; Safai Tehrani, F.; Zullo, A.; Alampi, G.; Amapane, N.; Arcidiacono, R.; Argiro, S.; Arneodo, M.; Bellan, R.; Benotto, F.; Biino, C.; Bolognesi, S.; Borgia, M. A.; Botta, C.; Brasolin, A.; Cartiglia, N.; Castello, R.; Cerminara, G.; Cirio, R.; Cordero, M.; Costa, M.; Dattola, D.; Daudo, F.; Dellacasa, G.; Demaria, N.; Dughera, G.; Dumitrache, F.; Farano, R.; Ferrero, G.; Filoni, E.; Kostyleva, G.; Larsen, H. E.; Mariotti, C.; Marone, M.; Maselli, S.; Menichetti, E.; Mereu, P.; Migliore, E.; Mila, G.; Monaco, V.; Musich, M.; Nervo, M.; Obertino, M. M.; Panero, R.; Parussa, A.; Pastrone, N.; Peroni, C.; Petrillo, G.; Romero, A.; Ruspa, M.; Sacchi, R.; Scalise, M.; Solano, A.; Staiano, A.; Trapani, P. P.; Trocino, D.; Vaniev, V.; Vilela Pereira, A.; Zampieri, A.; Belforte, S.; Cossutti, F.; Della Ricca, G.; Gobbo, B.; Kavka, C.; Penzo, A.; Kim, Y. E.; Nam, S. K.; Kim, D. H.; Kim, G. N.; Kim, J. C.; Kong, D. J.; Ro, S. R.; Son, D. C.; Park, S. Y.; Kim, Y. J.; Kim, J. Y.; Lim, I. T.; Pac, M. Y.; Lee, S. J.; Jung, S. Y.; Rhee, J. T.; Ahn, S. H.; Hong, B. S.; Jeng, Y. K.; Kang, M. H.; Kim, H. C.; Kim, J. H.; Kim, T. J.; Lee, K. S.; Lim, J. K.; Moon, D. H.; Park, I. C.; Park, S. K.; Ryu, M. S.; Sim, K.-S.; Son, K. J.; Hong, S. J.; Choi, Y. I.; Castilla Valdez, H.; Sanchez Hernandez, A.; Carrillo Moreno, S.; Morelos Pineda, A.; Aerts, A.; Van der Stok, P.; Weffers, H.; Allfrey, P.; Gray, R. N. C.; Hashimoto, M.; Krofcheck, D.; Bell, A. J.; Bernardino Rodrigues, N.; Butler, P. H.; Churchwell, S.; Knegjens, R.; Whitehead, S.; Williams, J. C.; Aftab, Z.; Ahmad, U.; Ahmed, I.; Ahmed, W.; Asghar, M. I.; Asghar, S.; Dad, G.; Hafeez, M.; Hoorani, H. R.; Hussain, I.; Hussain, N.; Iftikhar, M.; Khan, M. S.; Mehmood, K.; Osman, A.; Shahzad, H.; Zafar, A. R.; Ali, A.; Bashir, A.; Jan, A. M.; Kamal, A.; Khan, F.; Saeed, M.; Tanwir, S.; Zafar, M. A.; Blocki, J.; Cyz, A.; Gladysz-Dziadus, E.; Mikocki, S.; Rybczynski, M.; Turnau, J.; Wlodarczyk, Z.; Zychowski, P.; Bunkowski, K.; Cwiok, M.; Czyrkowski, H.; Dabrowski, R.; Dominik, W.; Doroba, K.; Kalinowski, A.; Kierzkowski, K.; Konecki, M.; Krolikowski, J.; Kudla, I. M.; Pietrusinski, M.; Pozniak, K.; Zabolotny, W.; Zych, P.; Gokieli, R.; Goscilo, L.; Górski, M.; Nawrocki, K.; Traczyk, P.; Wrochna, G.; Zalewski, P.; Pozniak, K. T.; Romaniuk, R.; Zabolotny, W. M.; Alemany-Fernandez, R.; Almeida, C.; Almeida, N.; Araujo Vila Verde, A. S.; Barata Monteiro, T.; Bluj, M.; Da Mota Silva, S.; Tinoco Mendes, A. David; Freitas Ferreira, M.; Gallinaro, M.; Husejko, M.; Jain, A.; Kazana, M.; Musella, P.; Nobrega, R.; Rasteiro Da Silva, J.; Ribeiro, P. Q.; Santos, M.; Silva, P.; Silva, S.; Teixeira, I.; Teixeira, J. P.; Varela, J.; Varner, G.; Vaz Cardoso, N.; Altsybeev, I.; Babich, K.; Belkov, A.; Belotelov, I.; Bunin, P.; Chesnevskaya, S.; Elsha, V.; Ershov, Y.; Filozova, I.; Finger, M.; Finger, M., Jr.; Golunov, A.; Golutvin, I.; Gorbounov, N.; Gramenitski, I.; Kalagin, V.; Kamenev, A.; Karjavin, V.; Khabarov, S.; Khabarov, V.; Kiryushin, Y.; Konoplyanikov, V.; Korenkov, V.; Kozlov, G.; Kurenkov, A.; Lanev, A.; Lysiakov, V.; Malakhov, A.; Melnitchenko, I.; Mitsyn, V. V.; Moisenz, K.; Moisenz, P.; Movchan, S.; Nikonov, E.; Oleynik, D.; Palichik, V.; Perelygin, V.; Petrosyan, A.; Rogalev, E.; Samsonov, V.; Savina, M.; Semenov, R.; Sergeev, S.; Shmatov, S.; Shulha, S.; Smirnov, V.; Smolin, D.; Tcheremoukhine, A.; Teryaev, O.; Tikhonenko, E.; Urkinbaev, A.; Vasil'ev, S.; Vishnevskiy, A.; Volodko, A.; Zamiatin, N.; Zarubin, A.; Zarubin, P.; Zubarev, E.; Bondar, N.; Gavrikov, Y.; Golovtsov, V.; Ivanov, Y.; Kim, V.; Kozlov, V.; Lebedev, V.; Makarenkov, G.; Moroz, F.; Neustroev, P.; Obrant, G.; Orishchin, E.; Petrunin, A.; Shcheglov, Y.; Shchetkovskiy, A.; Sknar, V.; Skorobogatov, V.; Smirnov, I.; Sulimov, V.; Tarakanov, V.; Uvarov, L.; Vavilov, S.; Velichko, G.; Volkov, S.; Vorobyev, A.; Chmelev, D.; Druzhkin, D.; Ivanov, A.; Kudinov, V.; Logatchev, O.; Onishchenko, S.; Orlov, A.; Sakharov, V.; Smetannikov, V.; Tikhomirov, A.; Zavodthikov, S.; Andreev, Yu; Anisimov, A.; Duk, V.; Gninenko, S.; Golubev, N.; Gorbunov, D.; Kirsanov, M.; Krasnikov, N.; Matveev, V.; Pashenkov, A.; Pastsyak, A.; Postoev, V. E.; Sadovski, A.; Skassyrskaia, A.; Solovey, Alexander; Solovey, Anatoly; Soloviev, D.; Toropin, A.; Troitsky, S.; Alekhin, A.; Baldov, A.; Epshteyn, V.; Gavrilov, V.; Ilina, N.; Kaftanov, V.; Karpishin, V.; Kiselevich, I.; Kolosov, V.; Kossov, M.; Krokhotin, A.; Kuleshov, S.; Oulianov, A.; Pozdnyakov, A.; Safronov, G.; Semenov, S.; Stepanov, N.; Stolin, V.; Vlasov, E.; Zaytsev, V.; Boos, E.; Dubinin, M.; Dudko, L.; Ershov, A.; Eyyubova, G.; Gribushin, A.; Ilyin, V.; Klyukhin, V.; Kodolova, O.; Kruglov, N. A.; Kryukov, A.; Lokhtin, I.; Malinina, L.; Mikhaylin, V.; Petrushanko, S.; Sarycheva, L.; Savrin, V.; Shamardin, L.; Sherstnev, A.; Snigirev, A.; Teplov, K.; Vardanyan, I.; Fomenko, A. M.; Konovalova, N.; Kozlov, V.; Lebedev, A. I.; Lvova, N.; Rusakov, S. V.; Terkulov, A.; Abramov, V.; Akimenko, S.; Artamonov, A.; Ashimova, A.; Azhgirey, I.; Bitioukov, S.; Chikilev, O.; Datsko, K.; Filine, A.; Godizov, A.; Goncharov, P.; Grishin, V.; Inyakin, A.; Kachanov, V.; Kalinin, A.; Khmelnikov, A.; Konstantinov, D.; Korablev, A.; Krychkine, V.; Krinitsyn, A.; Levine, A.; Lobov, I.; Lukanin, V.; Mel'nik, Y.; Molchanov, V.; Petrov, V.; Petukhov, V.; Pikalov, V.; Ryazanov, A.; Ryutin, R.; Shelikhov, V.; Skvortsov, V.; Slabospitsky, S.; Sobol, A.; Sytine, A.; Talov, V.; Tourtchanovitch, L.; Troshin, S.; Tyurin, N.; Uzunian, A.; Volkov, A.; Zelepoukine, S.; Lukyanov, V.; Mamaeva, G.; Prilutskaya, Z.; Rumyantsev, I.; Sokha, S.; Tataurschikov, S.; Vasilyev, I.; Adzic, P.; Anicin, I.; Djordjevic, M.; Jovanovic, D.; Maletic, D.; Puzovic, J.; Smiljkovic, N.; Aguayo Navarrete, E.; Aguilar-Benitez, M.; Ahijado Munoz, J.; Alarcon Vega, J. M.; Alberdi, J.; Alcaraz Maestre, J.; Aldaya Martin, M.; Arce, P.; Barcala, J. M.; Berdugo, J.; Blanco Ramos, C. L.; Burgos Lazaro, C.; Caballero Bejar, J.; Calvo, E.; Cerrada, M.; Chamizo Llatas, M.; Chercoles Catalán, J. J.; Colino, N.; Daniel, M.; DeLa Cruz, B.; Delgado Peris, A.; Fernandez Bedoya, C.; Ferrando, A.; Fouz, M. C.; Francia Ferrero, D.; Garcia Romero, J.; Garcia-Abia, P.; Gonzalez Lopez, O.; Hernandez, J. M.; Josa, M. I.; Marin, J.; Merino, G.; Molinero, A.; Navarrete, J. J.; Oller, J. C.; Puerta Pelayo, J.; Puras Sanchez, J. C.; Ramirez, J.; Romero, L.; Villanueva Munoz, C.; Willmott, C.; Yuste, C.; Albajar, C.; de Trocóniz, J. F.; Jimenez, I.; Macias, R.; Teixeira, R. F.; Cuevas, J.; Fernández Menéndez, J.; Gonzalez Caballero, I.; Lopez-Garcia, J.; Naves Sordo, H.; Vizan Garcia, J. M.; Cabrillo, I. J.; Calderon, A.; Cano Fernandez, D.; Diaz Merino, I.; Duarte Campderros, J.; Fernandez, M.; Fernandez Menendez, J.; Figueroa, C.; Garcia Moral, L. A.; Gomez, G.; Gomez Casademunt, F.; Gonzalez Sanchez, J.; Gonzalez Suarez, R.; Jorda, C.; Lobelle Pardo, P.; Lopez Garcia, A.; Lopez Virto, A.; Marco, J.; Marco, R.; Martinez Rivero, C.; Martinez Ruiz del Arbol, P.; Matorras, F.; Orviz Fernandez, P.; Patino Revuelta, A.; Rodrigo, T.; Rodriguez Gonzalez, D.; Ruiz Jimeno, A.; Scodellaro, L.; Sobron Sanudo, M.; Vila, I.; Vilar Cortabitarte, R.; Barbero, M.; Goldin, D.; Henrich, B.; Tauscher, L.; Vlachos, S.; Wadhwa, M.; Abbaneo, D.; Abbas, S. M.; Ahmed, I.; Akhtar, S.; Akhtar, M. I.; Albert, E.; Alidra, M.; Ashby, S.; Aspell, P.; Auffray, E.; Baillon, P.; Ball, A.; Bally, S. L.; Bangert, N.; Barillère, R.; Barney, D.; Beauceron, S.; Beaudette, F.; Benelli, G.; Benetta, R.; Benichou, J. L.; Bialas, W.; Bjorkebo, A.; Blechschmidt, D.; Bloch, C.; Bloch, P.; Bonacini, S.; Bos, J.; Bosteels, M.; Boyer, V.; Branson, A.; Breuker, H.; Bruneliere, R.; Buchmuller, O.; Campi, D.; Camporesi, T.; Caner, A.; Cano, E.; Carrone, E.; Cattai, A.; Chatelain, J. P.; Chauvey, M.; Christiansen, T.; Ciganek, M.; Cittolin, S.; Cogan, J.; Conde Garcia, A.; Cornet, H.; Corrin, E.; Corvo, M.; Cucciarelli, S.; Curé, B.; D'Enterria, D.; DeRoeck, A.; de Visser, T.; Delaere, C.; Delattre, M.; Deldicque, C.; Delikaris, D.; Deyrail, D.; Di Vincenzo, S.; Domeniconi, A.; Dos Santos, S.; Duthion, G.; Edera, L. M.; Elliott-Peisert, A.; Eppard, M.; Fanzago, F.; Favre, M.; Foeth, H.; Folch, R.; Frank, N.; Fratianni, S.; Freire, M. A.; Frey, A.; Fucci, A.; Funk, W.; Gaddi, A.; Gagliardi, F.; Gastal, M.; Gateau, M.; Gayde, J. C.; Gerwig, H.; Ghezzi, A.; Gigi, D.; Gill, K.; Giolo-Nicollerat, A. S.; Girod, J. P.; Glege, F.; Glessing, W.; Gomez-Reino Garrido, R.; Goudard, R.; Grabit, R.; Grillet, J. P.; Gutierrez Llamas, P.; Gutierrez Mlot, E.; Gutleber, J.; Hall-wilton, R.; Hammarstrom, R.; Hansen, M.; Harvey, J.; Hervé, A.; Hill, J.; Hoffmann, H. F.; Holzner, A.; Honma, A.; Hufnagel, D.; Huhtinen, M.; Ilie, S. D.; Innocente, V.; Jank, W.; Janot, P.; Jarron, P.; Jeanrenaud, M.; Jouvel, P.; Kerkach, R.; Kloukinas, K.; Kottelat, L. J.; Labbé, J. C.; Lacroix, D.; Lagrue, X.; Lasseur, C.; Laure, E.; Laurens, J. F.; Lazeyras, P.; LeGoff, J. M.; Lebeau, M.; Lecoq, P.; Lemeilleur, F.; Lenzi, M.; Leonardo, N.; Leonidopoulos, C.; Letheren, M.; Liendl, M.; Limia-Conde, F.; Linssen, L.; Ljuslin, C.; Lofstedt, B.; Loos, R.; Lopez Perez, J. A.; Lourenco, C.; Lyonnet, A.; Machard, A.; Mackenzie, R.; Magini, N.; Maire, G.; Malgeri, L.; Malina, R.; Mannelli, M.; Marchioro, A.; Martin, J.; Meijers, F.; Meridiani, P.; Meschi, E.; Meyer, T.; Meynet Cordonnier, A.; Michaud, J. F.; Mirabito, L.; Moser, R.; Mossiere, F.; Muffat-Joly, J.; Mulders, M.; Mulon, J.; Murer, E.; Mättig, P.; Oh, A.; Onnela, A.; Oriunno, M.; Orsini, L.; Osborne, J. A.; Paillard, C.; Pal, I.; Papotti, G.; Passardi, G.; Patino-Revuelta, A.; Patras, V.; Perea Solano, B.; Perez, E.; Perinic, G.; Pernot, J. F.; Petagna, P.; Petiot, P.; Petit, P.; Petrilli, A.; Pfeiffer, A.; Piccut, C.; Pimiä, M.; Pintus, R.; Pioppi, M.; Placci, A.; Pollet, L.; Postema, H.; Price, M. J.; Principe, R.; Racz, A.; Radermacher, E.; Ranieri, R.; Raymond, G.; Rebecchi, P.; Rehn, J.; Reynaud, S.; Rezvani Naraghi, H.; Ricci, D.; Ridel, M.; Risoldi, M.; Rodrigues Simoes Moreira, P.; Rohlev, A.; Roiron, G.; Rolandi, G.; Rumerio, P.; Runolfsson, O.; Ryjov, V.; Sakulin, H.; Samyn, D.; Santos Amaral, L. C.; Sauce, H.; Sbrissa, E.; Scharff-Hansen, P.; Schieferdecker, P.; Schlatter, W. D.; Schmitt, B.; Schmuecker, H. G.; Schröder, M.; Schwick, C.; Schäfer, C.; Segoni, I.; Sempere Roldán, P.; Sgobba, S.; Sharma, A.; Siegrist, P.; Sigaud, C.; Sinanis, N.; Sobrier, T.; Sphicas, P.; Spiropulu, M.; Stefanini, G.; Strandlie, A.; Szoncsó, F.; Taylor, B. G.; Teller, O.; Thea, A.; Tournefier, E.; Treille, D.; Tropea, P.; Troska, J.; Tsesmelis, E.; Tsirou, A.; Valls, J.; Van Vulpen, I.; Vander Donckt, M.; Vasey, F.; Vazquez Acosta, M.; Veillet, L.; Vichoudis, P.; Waurick, G.; Wellisch, J. P.; Wertelaers, P.; Wilhelmsson, M.; Willers, I. M.; Winkler, M.; Zanetti, M.; Bertl, W.; Deiters, K.; Dick, P.; Erdmann, W.; Feichtinger, D.; Gabathuler, K.; Hochman, Z.; Horisberger, R.; Ingram, Q.; Kaestli, H. C.; Kotlinski, D.; König, S.; Poerschke, P.; Renker, D.; Rohe, T.; Sakhelashvili, T.; Starodumov, A.; Aleksandrov, V.; Behner, F.; Beniozef, I.; Betev, B.; Blau, B.; Brett, A. M.; Caminada, L.; Chen, Z.; Chivarov, N.; Da Silva Di Calafiori, D.; Dambach, S.; Davatz, G.; Delachenal, V.; Della Marina, R.; Dimov, H.; Dissertori, G.; Dittmar, M.; Djambazov, L.; Dröge, M.; Eggel, C.; Ehlers, J.; Eichler, R.; Elmiger, M.; Faber, G.; Freudenreich, K.; Fuchs, J. F.; Georgiev, G. M.; Grab, C.; Haller, C.; Herrmann, J.; Hilgers, M.; Hintz, W.; Hofer, Hans; Hofer, Heinz; Horisberger, U.; Horvath, I.; Hristov, A.; Humbertclaude, C.; Iliev, B.; Kastli, W.; Kruse, A.; Kuipers, J.; Langenegger, U.; Lecomte, P.; Lejeune, E.; Leshev, G.; Lesmond, C.; List, B.; Luckey, P. D.; Lustermann, W.; Maillefaud, J. D.; Marchica, C.; Maurisset, A.; Meier, B.; Milenovic, P.; Milesi, M.; Moortgat, F.; Nanov, I.; Nardulli, A.; Nessi-Tedaldi, F.; Panev, B.; Pape, L.; Pauss, F.; Petrov, E.; Petrov, G.; Peynekov, M. M.; Pitzl, D.; Punz, T.; Riboni, P.; Riedlberger, J.; Rizzi, A.; Ronga, F. J.; Roykov, P. A.; Röser, U.; Schinzel, D.; Schöning, A.; Sourkov, A.; Stanishev, K.; Stoenchev, S.; Stöckli, F.; Suter, H.; Trüb, P.; Udriot, S.; Uzunova, D. G.; Veltchev, I.; Viertel, G.; von Gunten, H. P.; Waldmeier-Wicki, S.; Weber, R.; Weber, M.; Weng, J.; Wensveen, M.; Wittgenstein, F.; Zagoursky, K.; Alagoz, E.; Amsler, C.; Chiochia, V.; Hoermann, C.; Regenfus, C.; Robmann, P.; Rommerskirchen, T.; Schmidt, A.; Steiner, S.; Tsirigkas, D.; Wilke, L.; Blyth, S.; Chang, Y. H.; Chen, E. A.; Go, A.; Hung, C. C.; Kuo, C. M.; Li, S. W.; Lin, W.; Chang, P.; Chao, Y.; Chen, K. F.; Gao, Z.; Hou, G. W. S.; Hsiung, Y. B.; Lei, Y. J.; Lin, S. W.; Lu, R. S.; Shiu, J. G.; Tzeng, Y. M.; Ueno, K.; Velikzhanin, Y.; Wang, C. C.; Wang, M.-Z.; Aydin, S.; Azman, A.; Bakirci, M. N.; Basegmez, S.; Cerci, S.; Dumanoglu, I.; Erturk, S.; Eskut, E.; Kayis Topaksu, A.; Kisoglu, H.; Kurt, P.; Ozdemir, K.; Ozdes Koca, N.; Ozkurt, H.; Ozturk, S.; Polatöz, A.; Sogut, K.; Topakli, H.; Vergili, M.; Önengüt, G.; Gamsizkan, H.; Sekmen, S.; Serin-Zeyrek, M.; Sever, R.; Zeyrek, M.; Deliomeroglu, M.; Gülmez, E.; Isiksal, E.; Kaya, M.; Kaya, O.; Ozkorucuklu, S.; Sonmez, N.; Grinev, B.; Lyubynskiy, V.; Senchyshyn, V.; Levchuk, L.; Lukyanenko, S.; Soroka, D.; Sorokin, P.; Zub, S.; Anjum, A.; Baker, N.; Hauer, T.; McClatchey, R.; Odeh, M.; Rogulin, D.; Solomonides, A.; Brooke, J. J.; Croft, R.; Cussans, D.; Evans, D.; Frazier, R.; Grant, N.; Hansen, M.; Head, R. D.; Heath, G. P.; Heath, H. F.; Hill, C.; Huckvale, B.; Jackson, J.; Lynch, C.; Mackay, C. K.; Metson, S.; Nash, S. J.; Newbold, D. M.; Presland, A. D.; Probert, M. G.; Reid, E. C.; Smith, V. J.; Tapper, R. J.; Walton, R.; Bateman, E.; Bell, K. W.; Brown, R. M.; Camanzi, B.; Church, I. T.; Cockerill, D. J. A.; Cole, J. E.; Connolly, J. F.; Coughlan, J. A.; Flower, P. S.; Ford, P.; Francis, V. B.; French, M. J.; Galagedera, S. B.; Gannon, W.; Gay, A. P. R.; Geddes, N. I.; Greenhalgh, R. J. S.; Halsall, R. N. J.; Haynes, W. J.; Hill, J. A.; Jacob, F. R.; Jeffreys, P. W.; Jones, L. L.; Kennedy, B. W.; Lintern, A. L.; Lodge, A. B.; Maddox, A. J.; Morrissey, Q. R.; Murray, P.; Patrick, G. N.; Pattison, C. A. X.; Pearson, M. R.; Quinton, S. P. H.; Rogers, G. J.; Salisbury, J. G.; Shah, A. A.; Shepherd-Themistocleous, C. H.; Smith, B. J.; Sproston, M.; Stephenson, R.; Taghavi, S.; Tomalin, I. R.; Torbet, M. J.; Williams, J. H.; Womersley, W. J.; Worm, S. D.; Xing, F.; Apollonio, M.; Arteche, F.; Bainbridge, R.; Barber, G.; Barrillon, P.; Batten, J.; Beuselinck, R.; Brambilla Hall, P. M.; Britton, D.; Cameron, W.; Clark, D. E.; Clark, I. W.; Colling, D.; Cripps, N.; Davies, G.; Della Negra, M.; Dewhirst, G.; Dris, S.; Foudas, C.; Fulcher, J.; Futyan, D.; Graham, D. J.; Greder, S.; Greenwood, S.; Hall, G.; Hassard, J. F.; Hays, J.; Iles, G.; Kasey, V.; Khaleeq, M.; Leaver, J.; Lewis, P.; MacEvoy, B. C.; Maroney, O.; McLeod, E. M.; Miller, D. G.; Nash, J.; Nikitenko, A.; Noah Messomo, E.; Noy, M.; Papageorgiou, A.; Pesaresi, M.; Petridis, K.; Price, D. R.; Qu, X.; Raymond, D. M.; Rose, A.; Rutherford, S.; Ryan, M. J.; Sciacca, F.; Seez, C.; Sharp, P.; Sidiropoulos, G.; Stettler, M.; Stoye, M.; Striebig, J.; Takahashi, M.; Tallini, H.; Tapper, A.; Timlin, C.; Toudup, L.; Virdee, T.; Wakefield, S.; Walsham, P.; Wardrope, D.; Wingham, M.; Zhang, Y.; Zorba, O.; Da Via, C.; Goitom, I.; Hobson, P. R.; Imrie, D. C.; Reid, I.; Selby, C.; Sharif, O.; Teodorescu, L.; Watts, S. J.; Yaselli, I.; Hazen, E.; Heering, A.; Heister, A.; Lawlor, C.; Lazic, D.; Machado, E.; Rohlf, J.; Sulak, L.; Varela Rodriguez, F.; Wu, S. X.; Avetisyan, A.; Bose, T.; Christofek, L.; Cutts, D.; Esen, S.; Hooper, R.; Landsberg, G.; Narain, M.; Nguyen, D.; Speer, T.; Tsang, K. V.; Breedon, R.; Case, M.; Chertok, M.; Conway, J.; Cox, P. T.; Dolen, J.; Erbacher, R.; Fisyak, Y.; Friis, E.; Grim, G.; Holbrook, B.; Ko, W.; Kopecky, A.; Lander, R.; Lin, F. C.; Lister, A.; Maruyama, S.; Pellett, D.; Rowe, J.; Searle, M.; Smith, J.; Soha, A.; Squires, M.; Tripathi, M.; Vasquez Sierra, R.; Veelken, C.; Andreev, V.; Arisaka, K.; Bonushkin, Y.; Chandramouly, S.; Cline, D.; Cousins, R.; Erhan, S.; Hauser, J.; Ignatenko, M.; Jarvis, C.; Lisowski, B.; Matthey, C.; Mohr, B.; Mumford, J.; Otwinowski, S.; Pischalnikov, Y.; Rakness, G.; Schlein, P.; Shi, Y.; Tannenbaum, B.; Tucker, J.; Valuev, V.; Wallny, R.; Wang, H. G.; Yang, X.; Zheng, Y.; Andreeva, J.; Babb, J.; Campana, S.; Chrisman, D.; Clare, R.; Ellison, J.; Fortin, D.; Gary, J. W.; Gorn, W.; Hanson, G.; Jeng, G. Y.; Kao, S. C.; Layter, J. G.; Liu, F.; Liu, H.; Luthra, A.; Pasztor, G.; Rick, H.; Satpathy, A.; Shen, B. C.; Stringer, R.; Sytnik, V.; Tran, P.; Villa, S.; Wilken, R.; Wimpenny, S.; Zer-Zion, D.; Branson, J. G.; Coarasa Perez, J. A.; Dusinberre, E.; Kelley, R.; Lebourgeois, M.; Letts, J.; Lipeles, E.; Mangano, B.; Martin, T.; Mojaver, M.; Muelmenstaedt, J.; Norman, M.; Paar, H. P.; Petrucci, A.; Pi, H.; Pieri, M.; Rana, A.; Sani, M.; Sharma, V.; Simon, S.; White, A.; Würthwein, F.; Yagil, A.; Affolder, A.; Allen, A.; Campagnari, C.; D'Alfonso, M.; Dierlamm, A.; Garberson, J.; Hale, D.; Incandela, J.; Kalavase, P.; Koay, S. A.; Kovalskyi, D.; Krutelyov, V.; Kyre, S.; Lamb, J.; Lowette, S.; Nikolic, M.; Pavlunin, V.; Rebassoo, F.; Ribnik, J.; Richman, J.; Rossin, R.; Shah, Y. S.; Stuart, D.; Swain, S.; Vlimant, J. R.; White, D.; Witherell, M.; Bornheim, A.; Bunn, J.; Chen, J.; Denis, G.; Galvez, P.; Gataullin, M.; Legrand, I.; Litvine, V.; Ma, Y.; Mao, R.; Nae, D.; Narsky, I.; Newman, H. B.; Orimoto, T.; Rogan, C.; Shevchenko, S.; Steenberg, C.; Su, X.; Thomas, M.; Timciuc, V.; van Lingen, F.; Veverka, J.; Voicu, B. R.; Weinstein, A.; Wilkinson, R.; Xia, Y.; Yang, Y.; Zhang, L. Y.; Zhu, K.; Zhu, R. Y.; Ferguson, T.; Jang, D. W.; Jun, S. Y.; Paulini, M.; Russ, J.; Terentyev, N.; Vogel, H.; Vorobiev, I.; Bunce, M.; Cumalat, J. P.; Dinardo, M. E.; Drell, B. R.; Ford, W. T.; Givens, K.; Heyburn, B.; Johnson, D.; Nauenberg, U.; Stenson, K.; Wagner, S. R.; Agostino, L.; Alexander, J.; Blekman, F.; Cassel, D.; Das, S.; Duboscq, J. E.; Gibbons, L. K.; Heltsley, B.; Jones, C. D.; Kuznetsov, V.; Patterson, J. R.; Riley, D.; Ryd, A.; Stroiney, S.; Sun, W.; Thom, J.; Vaughan, J.; Wittich, P.; Beetz, C. P.; Cirino, G.; Podrasky, V.; Sanzeni, C.; Winn, D.; Abdullin, S.; Afaq, M. A.; Albrow, M.; Amundson, J.; Apollinari, G.; Atac, M.; Badgett, W.; Bakken, J. A.; Baldin, B.; Banicz, K.; Bauerdick, L. A. T.; Baumbaugh, A.; Berryhill, J.; Bhat, P. C.; Binkley, M.; Bloch, I.; Borcherding, F.; Boubekeur, A.; Bowden, M.; Burkett, K.; Butler, J. N.; Cheung, H. W. K.; Chevenier, G.; Chlebana, F.; Churin, I.; Cihangir, S.; Dagenhart, W.; Demarteau, M.; Dykstra, D.; Eartly, D. P.; Elias, J. E.; Elvira, V. D.; Evans, D.; Fisk, I.; Freeman, J.; Gaines, I.; Gartung, P.; Geurts, F. J. M.; Giacchetti, L.; Glenzinski, D. A.; Gottschalk, E.; Grassi, T.; Green, D.; Grimm, C.; Guo, Y.; Gutsche, O.; Hahn, A.; Hanlon, J.; Harris, R. M.; Hesselroth, T.; Holm, S.; Holzman, B.; James, E.; Jensen, H.; Johnson, M.; Joshi, U.; Klima, B.; Kossiakov, S.; Kousouris, K.; Kowalkowski, J.; Kramer, T.; Kwan, S.; Lei, C. M.; Leininger, M.; Los, S.; Lueking, L.; Lukhanin, G.; Lusin, S.; Maeshima, K.; Marraffino, J. M.; Mason, D.; McBride, P.; Miao, T.; Moccia, S.; Mokhov, N.; Mrenna, S.; Murray, S. J.; Newman-Holmes, C.; Noeding, C.; O'Dell, V.; Paterno, M.; Petravick, D.; Pordes, R.; Prokofyev, O.; Ratnikova, N.; Ronzhin, A.; Sekhri, V.; Sexton-Kennedy, E.; Sfiligoi, I.; Shaw, T. M.; Skup, E.; Smith, R. P.; Spalding, W. J.; Spiegel, L.; Stavrianakou, M.; Stiehr, G.; Stone, A. L.; Suzuki, I.; Tan, P.; Tanenbaum, W.; Temple, L. E.; Tkaczyk, S.; Uplegger, L.; Vaandering, E. W.; Vidal, R.; Wands, R.; Wenzel, H.; Whitmore, J.; Wicklund, E.; Wu, W. M.; Wu, Y.; Yarba, J.; Yarba, V.; Yumiceva, F.; Yun, J. C.; Zimmerman, T.; Acosta, D.; Avery, P.; Barashko, V.; Bartalini, P.; Bourilkov, D.; Cavanaugh, R.; Dolinsky, S.; Drozdetskiy, A.; Field, R. D.; Fu, Y.; Furic, I. K.; Gorn, L.; Holmes, D.; Kim, B. J.; Klimenko, S.; Konigsberg, J.; Korytov, A.; Kotov, K.; Levchenko, P.; Madorsky, A.; Matchev, K.; Mitselmakher, G.; Pakhotin, Y.; Prescott, C.; Ramond, L.; Ramond, P.; Schmitt, M.; Scurlock, B.; Stasko, J.; Stoeck, H.; Wang, D.; Yelton, J.; Gaultney, V.; Kramer, L.; Lebolo, L. M.; Linn, S.; Markowitz, P.; Martinez, G.; Rodriguez, J. L.; Adams, T.; Askew, A.; Atramentov, O.; Bertoldi, M.; Dharmaratna, W. G. D.; Gershtein, Y.; Gleyzer, S. V.; Hagopian, S.; Hagopian, V.; Jenkins, C. J.; Johnson, K. F.; Prosper, H.; Simek, D.; Thomaston, J.; Baarmand, M.; Baksay, L.; Guragain, S.; Hohlmann, M.; Mermerkaya, H.; Ralich, R.; Vodopiyanov, I.; Adams, M. R.; Anghel, I. M.; Apanasevich, L.; Barannikova, O.; Bazterra, V. E.; Betts, R. R.; Dragoiu, C.; Garcia-Solis, E. J.; Gerber, C. E.; Hofman, D. J.; Hollis, R.; Iordanova, A.; Khalatian, S.; Mironov, C.; Shabalina, E.; Smoron, A.; Varelas, N.; Akgun, U.; Albayrak, E. A.; Ayan, A. S.; Briggs, R.; Cankocak, K.; Clarida, W.; Cooper, A.; Debbins, P.; Duru, F.; Fountain, M.; McCliment, E.; Merlo, J. P.; Mestvirishvili, A.; Miller, M. J.; Moeller, A.; Newsom, C. R.; Norbeck, E.; Olson, J.; Onel, Y.; Perera, L.; Schmidt, I.; Wang, S.; Yetkin, T.; Anderson, E. W.; Chakir, H.; Hauptman, J. M.; Lamsa, J.; Barnett, B. A.; Blumenfeld, B.; Chien, C. Y.; Giurgiu, G.; Gritsan, A.; Kim, D. W.; Lae, C. K.; Maksimovic, P.; Swartz, M.; Tran, N.; Baringer, P.; Bean, A.; Chen, J.; Coppage, D.; Grachov, O.; Murray, M.; Radicci, V.; Wood, J. S.; Zhukova, V.; Bandurin, D.; Bolton, T.; Kaadze, K.; Kahl, W. E.; Maravin, Y.; Onoprienko, D.; Sidwell, R.; Wan, Z.; Dahmes, B.; Gronberg, J.; Hollar, J.; Lange, D.; Wright, D.; Wuest, C. R.; Baden, D.; Bard, R.; Eno, S. C.; Ferencek, D.; Hadley, N. J.; Kellogg, R. G.; Kirn, M.; Kunori, S.; Lockner, E.; Ratnikov, F.; Santanastasio, F.; Skuja, A.; Toole, T.; Wang, L.; Wetstein, M.; Alver, B.; Ballintijn, M.; Bauer, G.; Busza, W.; Gomez Ceballos, G.; Hahn, K. A.; Harris, P.; Klute, M.; Kravchenko, I.; Li, W.; Loizides, C.; Ma, T.; Nahn, S.; Paus, C.; Pavlon, S.; Piedra Gomez, J.; Roland, C.; Roland, G.; Rudolph, M.; Stephans, G.; Sumorok, K.; Vaurynovich, S.; Wenger, E. A.; Wyslouch, B.; Bailleux, D.; Cooper, S.; Cushman, P.; DeBenedetti, A.; Dolgopolov, A.; Dudero, P. R.; Egeland, R.; Franzoni, G.; Gilbert, W. J.; Gong, D.; Grahl, J.; Haupt, J.; Klapoetke, K.; Kronkvist, I.; Kubota, Y.; Mans, J.; Rusack, R.; Sengupta, S.; Sherwood, B.; Singovsky, A.; Vikas, P.; Zhang, J.; Booke, M.; Cremaldi, L. M.; Godang, R.; Kroeger, R.; Reep, M.; Reidy, J.; Sanders, D. A.; Sonnek, P.; Summers, D.; Watkins, S.; Bloom, K.; Bockelman, B.; Claes, D. R.; Dominguez, A.; Eads, M.; Furukawa, M.; Keller, J.; Kelly, T.; Lundstedt, C.; Malik, S.; Snow, G. R.; Swanson, D.; Ecklund, K. M.; Iashvili, I.; Kharchilava, A.; Kumar, A.; Strang, M.; Alverson, G.; Barberis, E.; Boeriu, O.; Eulisse, G.; McCauley, T.; Musienko, Y.; Muzaffar, S.; Osborne, I.; Reucroft, S.; Swain, J.; Taylor, L.; Tuura, L.; Gobbi, B.; Kubantsev, M.; Kubik, A.; Ofierzynski, R. A.; Schmitt, M.; Spencer, E.; Stoynev, S.; Szleper, M.; Velasco, M.; Won, S.; Andert, K.; Baumbaugh, B.; Beiersdorf, B. A.; Castle, L.; Chorny, J.; Goussiou, A.; Hildreth, M.; Jessop, C.; Karmgard, D. J.; Kolberg, T.; Marchant, J.; Marinelli, N.; McKenna, M.; Ruchti, R.; Vigneault, M.; Wayne, M.; Wiand, D.; Bylsma, B.; Durkin, L. S.; Gilmore, J.; Gu, J.; Killewald, P.; Ling, T. Y.; Rush, C. J.; Sehgal, V.; Williams, G.; Adam, N.; Chidzik, S.; Denes, P.; Elmer, P.; Garmash, A.; Gerbaudo, D.; Halyo, V.; Jones, J.; Marlow, D.; Olsen, J.; Piroué, P.; Stickland, D.; Tully, C.; Werner, J. S.; Wildish, T.; Wynhoff, S.; Xie, Z.; Huang, X. T.; Lopez, A.; Mendez, H.; Ramirez Vargas, J. E.; Zatserklyaniy, A.; Apresyan, A.; Arndt, K.; Barnes, V. E.; Bolla, G.; Bortoletto, D.; Bujak, A.; Everett, A.; Fahling, M.; Garfinkel, A. F.; Gutay, L.; Ippolito, N.; Kozhevnikov, Y.; Laasanen, A. T.; Liu, C.; Maroussov, V.; Medved, S.; Merkel, P.; Miller, D. H.; Miyamoto, J.; Neumeister, N.; Pompos, A.; Roy, A.; Sedov, A.; Shipsey, I.; Cuplov, V.; Parashar, N.; Bargassa, P.; Lee, S. J.; Liu, J. H.; Maronde, D.; Matveev, M.; Nussbaum, T.; Padley, B. P.; Roberts, J.; Tumanov, A.; Bodek, A.; Budd, H.; Cammin, J.; Chung, Y. S.; DeBarbaro, P.; Demina, R.; Ginther, G.; Gotra, Y.; Korjenevski, S.; Miner, D. C.; Sakumoto, W.; Slattery, P.; Zielinski, M.; Bhatti, A.; Demortier, L.; Goulianos, K.; Hatakeyama, K.; Mesropian, C.; Bartz, E.; Chuang, S. H.; Doroshenko, J.; Halkiadakis, E.; Jacques, P. F.; Khits, D.; Lath, A.; Macpherson, A.; Plano, R.; Rose, K.; Schnetzer, S.; Somalwar, S.; Stone, R.; Watts, T. L.; Cerizza, G.; Hollingsworth, M.; Lazoflores, J.; Ragghianti, G.; Spanier, S.; York, A.; Aurisano, A.; Golyash, A.; Kamon, T.; Nguyen, C. N.; Pivarski, J.; Safonov, A.; Toback, D.; Weinberger, M.; Akchurin, N.; Berntzon, L.; Carrell, K. W.; Gumus, K.; Jeong, C.; Kim, H.; Lee, S. W.; McGonagill, B. G.; Roh, Y.; Sill, A.; Spezziga, M.; Thomas, R.; Volobouev, I.; Washington, E.; Wigmans, R.; Yazgan, E.; Bapty, T.; Engh, D.; Florez, C.; Johns, W.; Keskinpala, T.; Luiggi Lopez, E.; Neema, S.; Nordstrom, S.; Pathak, S.; Sheldon, P.; Andelin, D.; Arenton, M. W.; Balazs, M.; Buehler, M.; Conetti, S.; Cox, B.; Hirosky, R.; Humphrey, M.; Imlay, R.; Ledovskoy, A.; Phillips, D., II; Powell, H.; Ronquest, M.; Yohay, R.; Anderson, M.; Baek, Y. W.; Bellinger, J. N.; Bradley, D.; Cannarsa, P.; Carlsmith, D.; Crotty, I.; Dasu, S.; Feyzi, F.; Gorski, T.; Gray, L.; Grogg, K. S.; Grothe, M.; Jaworski, M.; Klabbers, P.; Klukas, J.; Lanaro, A.; Lazaridis, C.; Leonard, J.; Loveless, R.; Magrans de Abril, M.; Mohapatra, A.; Ott, G.; Smith, W. H.; Weinberg, M.; Wenman, D.; Atoian, G. S.; Dhawan, S.; Issakov, V.; Neal, H.; Poblaguev, A.; Zeller, M. E.; Abdullaeva, G.; Avezov, A.; Fazylov, M. I.; Gasanov, E. M.; Khugaev, A.; Koblik, Y. N.; Nishonov, M.; Olimov, K.; Umaraliev, A.; Yuldashev, B. S.

2008-08-01

The Compact Muon Solenoid (CMS) detector is described. The detector operates at the Large Hadron Collider (LHC) at CERN. It was conceived to study proton-proton (and lead-lead) collisions at a centre-of-mass energy of 14 TeV (5.5 TeV nucleon-nucleon) and at luminosities up to 1034 cm-2 s-1 (1027 cm-2 s-1). At the core of the CMS detector sits a high-magnetic-field and large-bore superconducting solenoid surrounding an all-silicon pixel and strip tracker, a lead-tungstate scintillating-crystals electromagnetic calorimeter, and a brass-scintillator sampling hadron calorimeter. The iron yoke of the flux-return is instrumented with four stations of muon detectors covering most of the 4π solid angle. Forward sampling calorimeters extend the pseudorapidity coverage to high values (|η| <= 5) assuring very good hermeticity. The overall dimensions of the CMS detector are a length of 21.6 m, a diameter of 14.6 m and a total weight of 12500 t.

FLUKA Monte Carlo simulations and benchmark measurements for the LHC beam loss monitors

NASA Astrophysics Data System (ADS)

Sarchiapone, L.; Brugger, M.; Dehning, B.; Kramer, D.; Stockner, M.; Vlachoudis, V.

2007-10-01

One of the crucial elements in terms of machine protection for CERN's Large Hadron Collider (LHC) is its beam loss monitoring (BLM) system. On-line loss measurements must prevent the superconducting magnets from quenching and protect the machine components from damages due to unforeseen critical beam losses. In order to ensure the BLM's design quality, in the final design phase of the LHC detailed FLUKA Monte Carlo simulations were performed for the betatron collimation insertion. In addition, benchmark measurements were carried out with LHC type BLMs installed at the CERN-EU high-energy Reference Field facility (CERF). This paper presents results of FLUKA calculations performed for BLMs installed in the collimation region, compares the results of the CERF measurement with FLUKA simulations and evaluates related uncertainties. This, together with the fact that the CERF source spectra at the respective BLM locations are comparable with those at the LHC, allows assessing the sensitivity of the performed LHC design studies.

Planck 2010

ScienceCinema

None

2017-12-09

Planck 2010 From the Planck Scale to the ElectroWeak Scale The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC.Topics to be discussed: Supersymmetry Supergravity & string phenomenology Extra dimensions Electroweak symmetry breaking LHC and Tevatron Physics Collider physics Flavor & neutrinos physics Astroparticle & cosmology Gravity & holography Strongly coupled physics & CFT Registration: registration will be open until May 1st. Registration fees amount to 150 CHF and cover the cost of the coffee breaks and the social dinner. Payment has to be made online. The deadline for registration has been postponed to May 7th. However, after May 3th, we shall not accept any talk request any more. The meeting will be partly supported by ° the Marie Curie Initial Training Network "UNILHC" PITN-GA-2009-23792, ° the ERC Advanced Grant "MassTeV" 226371, ° and the CERN-TH unit.

Measured and simulated heavy-ion beam loss patterns at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Hermes, P. D.; Bruce, R.; Jowett, J. M.; Redaelli, S.; Salvachua Ferrando, B.; Valentino, G.; Wollmann, D.

2016-05-01

The Large Hadron Collider (LHC) at CERN pushes forward to new regimes in terms of beam energy and intensity. In view of the combination of very energetic and intense beams together with sensitive machine components, in particular the superconducting magnets, the LHC is equipped with a collimation system to provide protection and intercept uncontrolled beam losses. Beam losses could cause a superconducting magnet to quench, or in the worst case, damage the hardware. The collimation system, which is optimized to provide a good protection with proton beams, has shown a cleaning efficiency with heavy-ion beams which is worse by up to two orders of magnitude. The reason for this reduced cleaning efficiency is the fragmentation of heavy-ion beams into isotopes with a different mass to charge ratios because of the interaction with the collimator material. In order to ensure sufficient collimation performance in future ion runs, a detailed theoretical understanding of ion collimation is needed. The simulation of heavy-ion collimation must include processes in which 82 + 208Pb ions fragment into dozens of new isotopes. The ions and their fragments must be tracked inside the magnetic lattice of the LHC to determine their loss positions. This paper gives an overview of physical processes important for the description of heavy-ion loss patterns. Loss maps simulated by means of the two tools ICOSIM [1,2] and the newly developed STIER (SixTrack with Ion-Equivalent Rigidities) are compared with experimental data measured during LHC operation. The comparison shows that the tool STIER is in better agreement.

Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider

DOE PAGES

Adam, J.

2016-01-19

ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic ray interactions in the upper atmosphere. Here, we present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. Our analysis exploits the large size and excellent tracking capability of the ALICE Time Projection Chamber. A special emphasis is given to the study of high multiplicity events containing more thanmore » 100 reconstructed muons and corresponding to a muon areal density rho(mu) > 5.9 m(-2). Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP. While these experiments were able to reproduce the measured muon multiplicity distribution with Monte Carlo simulations at low and intermediate multiplicities, their simulations failed to describe the frequency of the highest multiplicity events. In this work we show that the high multiplicity events observed in ALICE stem from primary cosmic rays with energies above 10(16) eV and that the frequency of these events can be successfully described by assuming a heavy mass composition of primary cosmic rays in this energy range. Furthermore, the development of the resulting air showers was simulated using the latest version of QGSJET to model hadronic interactions. This observation places significant constraints on alternative, more exotic, production mechanisms for these events.« less

[The Big Data Game : On the Ludic Constitution of the Collaborative Production of Knowledge in High-Energy Physics at CERN].

PubMed

Dippel, Anne

2017-12-01

This article looks at how games and play contribute to the big data-driven production of knowledge in High-Energy Physics, with a particular focus on the Large Hadron Collider (LHC) at the European Organization for Nuclear Research (CERN), where the author has been conducting anthropological fieldwork since 2014. The ludic (playful) aspect of knowledge production is analyzed here in three different dimensions: the Symbolic, the Ontological, and the Epistemic. The first one points towards CERN as place where a cosmological game of probability is played with the help of Monte-Carlo simulations. The second one can be seen in the agonistic infrastructures of competing experimental collaborations. The third dimension unfolds in ludic platforms, such as online Challenges and citizen science games, which contribute to the development of machine learning algorithms, whose function is necessary in order to process the huge amount of data gathered from experimental events. Following Clifford Geertz, CERN itself is characterized as a site of deep play, a concept that contributes to understanding wider social and cultural orders through the analysis of ludic collective phenomena. The article also engages with Peter Galison's idea of the trading zone, proposing to comprehend it in the age of big data as a Playground. Thus the author hopes to contribute to a wider discussion in the historiographical and social study of science and technology, as well as in cultural anthropology, by recognizing the ludic in science as a central element of understanding collaborative knowledge production.

Quadrupole Alignment and Trajectory Correction for Future Linear Colliders: SLC Tests of a Dispersion-Free Steering Algorithm

DOE Office of Scientific and Technical Information (OSTI.GOV)

Assmann, R

2004-06-08

The feasibility of future linear colliders depends on achieving very tight alignment and steering tolerances. All proposals (NLC, JLC, CLIC, TESLA and S-BAND) currently require a total emittance growth in the main linac of less than 30-100% [1]. This should be compared with a 100% emittance growth in the much smaller SLC linac [2]. Major advances in alignment and beam steering techniques beyond those used in the SLC are necessary for the next generation of linear colliders. In this paper, we present an experimental study of quadrupole alignment with a dispersion-free steering algorithm. A closely related method (wakefield-free steering) takesmore » into account wakefield effects [3]. However, this method can not be studied at the SLC. The requirements for future linear colliders lead to new and unconventional ideas about alignment and beam steering. For example, no dipole correctors are foreseen for the standard trajectory correction in the NLC [4]; beam steering will be done by moving the quadrupole positions with magnet movers. This illustrates the close symbiosis between alignment, beam steering and beam dynamics that will emerge. It is no longer possible to consider the accelerator alignment as static with only a few surveys and realignments per year. The alignment in future linear colliders will be a dynamic process in which the whole linac, with thousands of beam-line elements, is aligned in a few hours or minutes, while the required accuracy of about 5 pm for the NLC quadrupole alignment [4] is a factor of 20 higher than in existing accelerators. The major task in alignment and steering is the accurate determination of the optimum beam-line position. Ideally one would like all elements to be aligned along a straight line. However, this is not practical. Instead a ''smooth curve'' is acceptable as long as its wavelength is much longer than the betatron wavelength of the accelerated beam. Conventional alignment methods are limited in accuracy by errors in the survey and the fiducials. Beam-based alignment methods ideally only depend upon the BPM resolution and generally provide much better precision. Many of those techniques are described in other contributions to this workshop. In this paper we describe our experiences with a dispersion-free steering algorithm for linacs. This algorithm was first suggested by Raubenheimer and Ruth in 1990 [5]. It h as been studied in simulations for NLC [5], TESLA [6], the S-BAND proposal [7] and CLIC [8]. The dispersion-free steering technique can be applied to the whole linac at once and returns the alignment (or trajectory) that minimizes the dispersive emittance growth of the beam. Thus it allows an extremely fast alignment of the beam-line. As we will show dispersion-free steering is only sensitive to quadrupole misalignments. Wakefield-free steering [3] as mentioned before is a closely related technique that minimizes the emittance growth caused by both dispersion and wakefields. Due to hardware limitations (i.e. insufficient relative range of power supplies) we could not study this method experimentally in the SLC. However, its systematics are very similar to those of dispersion-free steering. The studies of dispersion-free steering which are presented made extensive use of the unique potential of the SLC as the only operating linear collider. We used it to study the performance and problems of advanced beam-based optimization tools in a real beam-line environment and on a large scale. We should mention that the SLC has utilized beam-based alignment for years [9], using the difference of electron and positron trajectories. This method, however, cannot be used in future linear colliders. The goal of our work is to demonstrate the performance of advanced beam-based alignment techniques in linear colliders and to anticipate possible reality-related problems. Those can then be solved in the design state for the next generation of linear colliders.« less

Some Alignment Considerations for the Next Linear Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ruland, R

Next Linear Collider type accelerators require a new level of alignment quality. The relative alignment of these machines is to be maintained in an error envelope dimensioned in micrometers and for certain parts in nanometers. In the nanometer domain our terra firma cannot be considered monolithic but compares closer to jelly. Since conventional optical alignment methods cannot deal with the dynamics and cannot approach the level of accuracy, special alignment and monitoring techniques must be pursued.

Leading twist nuclear shadowing phenomena in hard processes with nuclei

DOE PAGES

L. Franfurt; Guzey, V.; Strikman, M.

2012-01-08

We present and discuss the theory and phenomenology of the leading twist theory of nuclear shadowing which is based on the combination of the generalization of Gribov-Glauber theory, QCD factorization theorems, and HERA QCD analysis of diffraction in lepton-proton deep inelastic scattering (DIS). We apply this technique for the analysis of a wide range of hard processes with nuclei-inclusive DIS on deuterons, medium-range and heavy nuclei, coherent and incoherent diffractive DIS with nuclei, and hard diffraction in proton-nucleus scattering - and make predictions for the effect of nuclear shadowing in the corresponding sea quark and gluon parton distributions. We alsomore » analyze the role of the leading twist nuclear shadowing in generalized parton distributions in nuclei and certain characteristics of final states in nuclear DIS. We discuss the limits of applicability of the leading twist approximation for small x scattering off nuclei and the onset of the black disk regime and methods of detecting it. It will be possible to check many of our predictions in the near future in the studies of the ultraperipheral collisions at the Large Hadron Collider (LHC). Further checks will be possible in pA collisions at the LHC and forward hadron production at Relativistic Heavy Ion Collider (RHIC). As a result, detailed tests will be possible at an Electon-Ion Collider (EIC) in USA and at the Large Hadron-Electron Collider (LHeC) at CERN.« less

Exploration of a High Luminosity 100 TeV Proton Antiproton Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Oliveros, Sandra J.; Summers, Don; Cremaldi, Lucien

New physics is being explored with the Large Hadron Collider at CERN and with Intensity Frontier programs at Fermilab and KEK. The energy scale for new physics is known to be in the multi-TeV range, signaling the need for a future collider which well surpasses this energy scale. We explore a 10more » $$^{\\,34}$$ cm$$^{-2}$$ s$$^{-1}$$ luminosity, 100 TeV $$p\\bar{p}$$ collider with 7$$\\times$$ the energy of the LHC but only 2$$\\times$$ as much NbTi superconductor, motivating the choice of 4.5 T single bore dipoles. The cross section for many high mass states is 10 times higher in $$p\\bar{p}$$ than $pp$ collisions. Antiquarks for production can come directly from an antiproton rather than indirectly from gluon splitting. The higher cross sections reduce the synchrotron radiation in superconducting magnets and the number of events per beam crossing, because lower beam currents can produce the same rare event rates. Events are more centrally produced, allowing a more compact detector with less space between quadrupole triplets and a smaller $$\\beta^{*}$$ for higher luminosity. A Fermilab-like $$\\bar p$$ source would disperse the beam into 12 momentum channels to capture more antiprotons. Because stochastic cooling time scales as the number of particles, 12 cooling ring sets would be used. Each set would include phase rotation to lower momentum spreads, equalize all momentum channels, and stochastically cool. One electron cooling ring would follow the stochastic cooling rings. Finally antiprotons would be recycled during runs without leaving the collider ring by joining them to new bunches with synchrotron damping.« less

RF pulse compression for future linear colliders

NASA Astrophysics Data System (ADS)

Wilson, Perry B.

1995-07-01

Future (nonsuperconducting) linear colliders will require very high values of peak rf power per meter of accelerating structure. The role of rf pulse compression in producing this power is examined within the context of overall rf system design for three future colliders at energies of 1.0-1.5 TeV, 5 TeV, and 25 TeV. In order to keep the average AC input power and the length of the accelerator within reasonable limits, a collider in the 1.0-1.5 TeV energy range will probably be built at an x-band rf frequency, and will require a peak power on the order of 150-200 MW per meter of accelerating structure. A 5 TeV collider at 34 GHz with a reasonable length (35 km) and AC input power (225 MW) would require about 550 MW per meter of structure. Two-beam accelerators can achieve peak powers of this order by applying dc pulse compression techniques (induction linac modules) to produce the drive beam. Klystron-driven colliders achieve high peak power by a combination of dc pulse compression (modulators) and rf pulse compression, with about the same overall rf system efficiency (30-40%) as a two-beam collider. A high gain (6.8) three-stage binary pulse compression system with high efficiency (80%) is described, which (compared to a SLED-II system) can be used to reduce the klystron peak power by about a factor of two, or alternatively, to cut the number of klystrons in half for a 1.0-1.5 TeV x-band collider. For a 5 TeV klystron-driven collider, a high gain, high efficiency rf pulse compression system is essential.

Computing the qg → qg cross section using the BCFW recursion and introduction to jet tomography in heavy ion collisions via MHV techniques

NASA Astrophysics Data System (ADS)

Rabemananajara, Tanjona R.; Horowitz, W. A.

2017-09-01

To make predictions for the particle physics processes, one has to compute the cross section of the specific process as this is what one can measure in a modern collider experiment such as the Large Hadron Collider (LHC) at CERN. Theoretically, it has been proven to be extremely difficult to compute scattering amplitudes using conventional methods of Feynman. Calculations with Feynman diagrams are realizations of a perturbative expansion and when doing calculations one has to set up all topologically different diagrams, for a given process up to a given order of coupling in the theory. This quickly makes the calculation of scattering amplitudes a hot mess. Fortunately, one can simplify calculations by considering the helicity amplitude for the Maximally Helicity Violating (MHV). This can be extended to the formalism of on-shell recursion, which is able to derive, in a much simpler way the expression of a high order scattering amplitude from lower orders.

Managing operational documentation in the ALICE Detector Control System

NASA Astrophysics Data System (ADS)

Lechman, M.; Augustinus, A.; Bond, P.; Chochula, P.; Kurepin, A.; Pinazza, O.; Rosinsky, P.

2012-12-01

ALICE (A Large Ion Collider Experiment) is one of the big LHC (Large Hadron Collider) experiments at CERN in Geneve, Switzerland. The experiment is composed of 18 sub-detectors controlled by an integrated Detector Control System (DCS) that is implemented using the commercial SCADA package PVSSII. The DCS includes over 1200 network devices, over 1,000,000 monitored parameters and numerous custom made software components that are prepared by over 100 developers from all around the world. This complex system is controlled by a single operator via a central user interface. One of his/her main tasks is the recovery of anomalies and errors that may occur during operation. Therefore, clear, complete and easily accessible documentation is essential to guide the shifter through the expert interfaces of different subsystems. This paper describes the idea of the management of the operational documentation in ALICE using a generic repository that is built on a relational database and is integrated with the control system. The experience gained and the conclusions drawn from the project are also presented.

Big Bang Day : Afternoon Play - Torchwood: Lost Souls

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2009-10-13

Martha Jones, ex-time traveller and now working as a doctor for a UN task force, has been called to CERN where they're about to activate the Large Hadron Collider. Once activated, the Collider will fire beams of protons together recreating conditions a billionth of a second after the Big Bang - and potentially allowing the human race a greater insight into what the Universe is made of. But so much could go wrong - it could open a gateway to a parallel dimension, or create a black hole - and now voices from the past are calling out to peoplemore » and scientists have started to disappear... Where have the missing scientists gone? What is the secret of the glowing man? What is lurking in the underground tunnel? And do the dead ever really stay dead? Lost Souls is a spin-off from the award-winning BBC Wales TV production Torchwood. It stars John Barrowman, Freema Agyeman, Eve Myles, Gareth David-Lloyd, Lucy Montgomery (of Titty Bang Bang) and Stephen Critchlow.« less

The Beginning of the Physics of Leptons

NASA Astrophysics Data System (ADS)

Ting, Samuel C. C.

Over the last 30 years the study of lepton pairs from both hadron and electron accelerators and colliders has led to the discovery of J, ϒ, Z and W particles. The study of acoplanar eμ pairs + missing energy has led to the discovery of the heavy lepton, now called τ lepton. Indeed, the study of lepton pairs with and without missing energy has become the main method in high energy colliders for searching new particles. This paper presents some of the important contributions made by Antonino Zichichi over a 10 year period at CERN and Frascati in opening this new field of physics. This includes the development of instrumentation to distinguish leptons from hadrons, the first experiment on lepton pair production from hadron machines, the precision tests of electrodynamics at very small distances, the production of hadrons from e+e- collisions and most importantly his invention of a new method e+e- → eμ + missing momenta, experimentally proving that, thanks to his new electron and muon detection technology, these signals have very little background.

Big Bang Day : Afternoon Play - Torchwood: Lost Souls

ScienceCinema

None

2017-12-09

Martha Jones, ex-time traveller and now working as a doctor for a UN task force, has been called to CERN where they're about to activate the Large Hadron Collider. Once activated, the Collider will fire beams of protons together recreating conditions a billionth of a second after the Big Bang - and potentially allowing the human race a greater insight into what the Universe is made of. But so much could go wrong - it could open a gateway to a parallel dimension, or create a black hole - and now voices from the past are calling out to people and scientists have started to disappear... Where have the missing scientists gone? What is the secret of the glowing man? What is lurking in the underground tunnel? And do the dead ever really stay dead? Lost Souls is a spin-off from the award-winning BBC Wales TV production Torchwood. It stars John Barrowman, Freema Agyeman, Eve Myles, Gareth David-Lloyd, Lucy Montgomery (of Titty Bang Bang) and Stephen Critchlow.

Precision Timing with Silicon Sensors for Use in Calorimetry

NASA Astrophysics Data System (ADS)

Bornheim, A.; Ronzhin, A.; Kim, H.; Bolla, G.; Pena, C.; Xie, S.; Apresyan, A.; Los, S.; Spiropulu, M.; Ramberg, E.

2017-11-01

The high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN is expected to provide instantaneous luminosities of 5 × 1034 cm -2 s -1. The high luminosities expected at the HL-LHC will be accompanied by a factor of 5 to 10 more pileup compared with LHC conditions in 2015, causing general confusion for particle identification and event reconstruction. Precision timing allows to extend calorimetric measurements into such a high density environment by subtracting the energy deposits from pileup interactions. Calorimeters employing silicon as the active component have recently become a popular choice for the HL- LHC and future collider experiments which face very high radiation environments. We present studies of basic calorimetric and precision timing measurements using a prototype composed of tungsten absorber and silicon sensor as the active medium. We show that for the bulk of electromagnetic showers induced by electrons in the range of 20 GeV to 30 GeV, we can achieve time resolutions better than 25 ps per single pad sensor.

A large hadron electron collider at CERN

DOE PAGES

Abelleira Fernandez, J. L.

2015-04-06

This document provides a brief overview of the recently published report on the design of the Large Hadron Electron Collider (LHeC), which comprises its physics programme, accelerator physics, technology and main detector concepts. The LHeC exploits and develops challenging, though principally existing, accelerator and detector technologies. This summary is complemented by brief illustrations of some of the highlights of the physics programme, which relies on a vastly extended kinematic range, luminosity and unprecedented precision in deep inelastic scattering. Illustrations are provided regarding high precision QCD, new physics (Higgs, SUSY) and eletron-ion physics. The LHeC is designed to run synchronously withmore » the LHC in the twenties and to achieve an integrated luminosity of O(100)fb –1. It will become the cleanest high resolution microscope of mankind and will substantially extend as well as complement the investigation of the physics of the TeV energy scale, which has been enabled by the LHC.« less

Development of superconducting links for the Large Hadron Collider machine

NASA Astrophysics Data System (ADS)

Ballarino, Amalia

2014-04-01

In the framework of the upgrade of the Large Hadron Collider (LHC) machine, new superconducting lines are being developed for the feeding of the LHC magnets. The proposed electrical layout envisages the location of the power converters in surface buildings, and the transfer of the current from the surface to the LHC tunnel, where the magnets are located, via superconducting links containing tens of cables feeding different circuits and transferring altogether more than 150 kA. Depending on the location, the links will have a length ranging from 300 m to 500 m, and they will span a vertical distance of about 80 m. An overview of the R&D program that has been launched by CERN is presented, with special attention to the development of novel types of cables made from MgB2 and high temperature superconductors (Bi-2223 and REBCO) and to the results of the tests performed on prototype links. Plans for future activities are presented, together with a timeline for potential future integration in the LHC machine.

Design of an Inductive Adder for the FCC injection kicker pulse generator

NASA Astrophysics Data System (ADS)

Woog, D.; Barnes, M. J.; Ducimetière, L.; Holma, J.; Kramer, T.

2017-07-01

The injection system for a 100 TeV centre-of-mass collider is an important part of the Future Circular Collider (FCC) study. Due to issues with conventional kicker systems, such as self-triggering and long term availability of thyratrons and limitations of HV-cables, innovative design changes are planned for the FCC injection kicker pulse generator. An inductive adder (IA) based on semiconductor (SC) switches is a promising technology for kicker systems. Its modular design, and the possibility of an active ripple suppression are significant advantages. Since the IA is a complex device, with multiple components whose characteristics are important, a detailed design study and construction of a prototype is necessary. This paper summarizes the system requirements and constraints, and describes the main components and design challenges of the prototype IA. It outlines the results from simulations and measurements on different magnetic core materials as well as on SC switches. The paper concludes on the design choices and progress for the prototype to be built at CERN.

Physics at the e⁺e⁻ linear collider

DOE PAGES

Moortgat-Picka, G.; Kronfeld, A. S.

2015-08-14

A comprehensive review of physics at an e⁺e⁻ linear collider in the energy range of √s = 92 GeV–3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focuses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.

Contributions to the mini-workshop on beam-beam compensation in the Tevatron

DOE Office of Scientific and Technical Information (OSTI.GOV)

Shiltsev, V.

1998-02-01

The purpose of the Workshop was to assay the current understanding of compensation of the beam-beam effects in the Tevatron with use of low-energy high-current electron beam, relevant accelerator technology, along with other novel techniques of the compensation and previous attempts. About 30 scientists representing seven institutions from four countries--FNAL, SLAC, BNL, Novosibirsk, CERN, and Dubna were in attendance. Twenty one talks were presented. The event gave firm ground for wider collaboration on experimental test of the compensation at the Tevatron collider. This report consists of vugraphs of talks given at the meeting.

Elastic pp-bar and pp scattering up to. sqrt. s = 546 GeV and the flavored perturbative Reggeon field theory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dash, J.W.; Jones, S.T.

We show that the perturbative Reggeon field theory (RFT) with flavoring corrections added reproduces the pp and pp-bar differential cross sections from Fermilab to the CERN SPS collider (Spp-bar S). This completes a long program of phenomenology which is now capable of providing a unified framework for soft hadronic scattering at current energies. Our scenario of data being influenced by finite scales at least up to ..sqrt..s = 546 GeV is compatible with the truly asymptotic limit being described by the critical RFT scaling laws.

[Towards an unified theory of the universe basic forces ("the everything theory")].

PubMed

Aguilar Peris, José

2004-01-01

Numerous efforts have been made in order to unify all the basic forces in nature. In 1967 the fusion of electromagnetic and weak forces was obtained and in 1973 a theoretical bridge between the electroweak and the strong forces have been constructed. This theory is waiting for experimental proofs in the CERN large hadron collider. The last stage would be "the everything theory", which includes the gravitational force. Only the so called superstring theory is a good candidate to overcome the incompatibility of the quantum mechanics and the general relativity, but this theory is not already achieved.

Top Quark and Higgs Boson Physics at LHC-ATLAS

NASA Astrophysics Data System (ADS)

Tomoto, M.

2013-03-01

One of the main goal of the Large Hadron Collider (LHC) experiments at CERN in Switzerland is to aim to solve the "origin of the mass" by discovering the Higgs boson and understanding the interaction of the Higgs boson with the elementary particles. The ATLAS, which is one of the LHC experiments has taken about 5 fb-1 of physics quality data and published several results with regard to the "origin of the mass" since March 2010. This presentation focuses on the latest results of the heaviest elementary particle, namely, top quark physics and the Higgs boson searches from ATLAS.

Elementary Particle Physics Experiment at the University of Massachusetts, Amherst

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brau, Benjamin; Dallapiccola, Carlo; Willocq, Stephane

2013-07-30

In this progress report we summarize the activities of the University of Massachusetts- Amherst group for the three years of this research project. We are fully engaged in research at the energy frontier with the ATLAS experiment at the CERN Large Hadron Collider. We have made leading contributions in software development and performance studies for the ATLAS Muon Spectrometer, as well as on physics analysis with an emphasis on Standard Model measurements and searches for physics beyond the Standard Model. In addition, we have increased our contributions to the Muon Spectrometer New Small Wheel upgrade project.

Web life: Planet SciCast

NASA Astrophysics Data System (ADS)

2009-08-01

So what is the site about? Planet SciCast is an online repository for short films about science - a bit like a science-specific, moderated version of YouTube. As of July 2009, the site hosts over 150 films on topics ranging from CERN's Large Hadron Collider to fun things to do with treacle. New content appears on the site every few weeks, and some films include links to information about related experiments, demos and activities. The site also runs an annual competition aimed at getting more people involved in making science films, with prizes in categories like "best original score" and "best presenter".

Design of an AdvancedTCA board management controller (IPMC)

NASA Astrophysics Data System (ADS)

Mendez, J.; Bobillier, V.; Haas, S.; Joos, M.; Mico, S.; Vasey, F.

2017-03-01

The AdvancedTCA (ATCA) standard has been selected as the hardware platform for the upgrade of the back-end electronics of the CMS and ATLAS experiments of the Large Hadron Collider (LHC) . In this context, the electronic systems for experiments group at CERN is running a project to evaluate, specify, design and support xTCA equipment. As part of this project, an Intelligent Platform Management Controller (IPMC) for ATCA blades, based on a commercial solution, has been designed to be used on existing and future ATCA blades. This paper reports on the status of this project presenting the hardware and software developments.

A MOdular System for Acquisition, Interface and Control (MOSAIC) of detectors and their related electronics for high energy physics experiment

NASA Astrophysics Data System (ADS)

Robertis, G. De; Fanizzi, G.; Loddo, F.; Manzari, V.; Rizzi, M.

2018-02-01

In this work the MOSAIC ("MOdular System for Acquisition, Interface and Control") board, designed for the readout and testing of the pixel modules for the silicon tracker upgrade of the ALICE (A Large Ion Collider Experiment) experiment at teh CERN LHC, is described. It is based on an Artix7 Field Programmable Gate Array device by Xilinx and is compliant with the six unit "Versa Modular Eurocard" standard (6U-VME) for easy housing in a standard VMEbus crate from which it takes only power supplies and cooling.

Flowgen: Flowchart-based documentation for C + + codes

NASA Astrophysics Data System (ADS)

Kosower, David A.; Lopez-Villarejo, J. J.

2015-11-01

We present the Flowgen tool, which generates flowcharts from annotated C + + source code. The tool generates a set of interconnected high-level UML activity diagrams, one for each function or method in the C + + sources. It provides a simple and visual overview of complex implementations of numerical algorithms. Flowgen is complementary to the widely-used Doxygen documentation tool. The ultimate aim is to render complex C + + computer codes accessible, and to enhance collaboration between programmers and algorithm or science specialists. We describe the tool and a proof-of-concept application to the VINCIA plug-in for simulating collisions at CERN's Large Hadron Collider.

Robert R. Wilson Prize III: Applications of Intrabeam Scattering Formulae to a Myriad of Accelerator Systems

NASA Astrophysics Data System (ADS)

Mtingwa, Sekazi K.

2017-01-01

We discuss our entree into accelerator physics and the problem of intrabeam scattering in particular. We focus on the historical importance of understanding intrabeam scattering for the successful operation of Fermilab's Accumulator and Tevatron and the subsequent hunt for the top quark, and its importance for successful operation of CERN's Large Hadron Collider that discovered the Higgs boson. We provide details on intrabeam scattering formalisms for hadron and electron beams at high energies, concluding with an Ansatz by Karl Bane that has applications to electron damping rings and synchrotron light sources.

Probing New Physics with Jets at the LHC

ScienceCinema

Harris, Robert

2017-12-09

The Large Hadron Collider at CERN has the potential to make a major discovery as early as 2008 from simple measurements of events with two high energy jets. This talk will present the jet trigger and analysis plans of the CMS collaboration, which were produced at the LHC Physics Center at Fermilab. Plans to search the two jet channel for generic signals of new particles and forces will be discussed. I will present the anticipated sensitivity of the CMS experiment to a variety of models of new physics, including quark compositeness, technicolor, superstrings, extra dimensions and grand unification.

Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adamczyk, L.; Adkins, J. K.; Agakishiev, G.

Balance functions have been measured in terms of relative pseudorapidity ( Δη ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider (RHIC) from Au + Au collisions atmore » $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at $$\\sqrt{s}$$$_{NN}$$ = 2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). Finally, the narrowing of the balance function in central collisions at $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV implies that a QGP is still being created at this relatively low energy.« less

Chiral magnetic and vortical effects in high-energy nuclear collisions—A status report

DOE PAGES

Kharzeev, D. E.; Liao, J.; Voloshin, S. A.; ...

2016-05-01

Here, the interplay of quantum anomalies with magnetic field and vorticity results in a variety of novel non-dissipative transport phenomena in systems with chiral fermions, including the quark–gluon plasma. Among them is the Chiral Magnetic Effect (CME)—the generation of electric current along an external magnetic field induced by chirality imbalance. Because the chirality imbalance is related to the global topology of gauge fields, the CME current is topologically protected and hence non-dissipative even in the presence of strong interactions. As a result, the CME and related quantum phenomena affect the hydrodynamical and transport behavior of strongly coupled quark–gluon plasma, andmore » can be studied in relativistic heavy ion collisions where strong magnetic fields are created by the colliding ions. Evidence for the CME and related phenomena has been reported by the STAR Collaboration at Relativistic Heavy Ion Collider at BNL, and by the ALICE Collaboration at the Large Hadron Collider at CERN. The goal of the present review is to provide an elementary introduction into the physics of anomalous chiral effects, to describe the current status of experimental studies in heavy ion physics, and to outline the future work, both in experiment and theory, needed to eliminate the existing uncertainties in the interpretation of the data.« less

Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

NASA Astrophysics Data System (ADS)

Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; Aggarwal, M. M.; Ahammed, Z.; Alekseev, I.; Alford, J.; Aparin, A.; Arkhipkin, D.; Aschenauer, E. C.; Averichev, G. S.; Banerjee, A.; Bellwied, R.; Bhasin, A.; Bhati, A. K.; Bhattarai, P.; Bielcik, J.; Bielcikova, J.; Bland, L. C.; Bordyuzhin, I. G.; Bouchet, J.; Brandin, A. V.; Bunzarov, I.; Burton, T. P.; Butterworth, J.; Caines, H.; Calderón de la Barca Sánchez, M.; Campbell, J. M.; Cebra, D.; Cervantes, M. C.; Chakaberia, I.; Chaloupka, P.; Chang, Z.; Chattopadhyay, S.; Chen, J. H.; Chen, H. F.; Cheng, J.; Cherney, M.; Christie, W.; Codrington, M. J. M.; Contin, G.; Crawford, H. J.; Cui, X.; Das, S.; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Deng, J.; Derevschikov, A. A.; Derradi de Souza, R.; di Ruzza, B.; Didenko, L.; Dilks, C.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, C. M.; Dunkelberger, L. E.; Dunlop, J. C.; Efimov, L. G.; Engelage, J.; Eppley, G.; Esha, R.; Evdokimov, O.; Eyser, O.; Fatemi, R.; Fazio, S.; Federic, P.; Fedorisin, J.; Feng, Filip, P.; Fisyak, Y.; Flores, C. E.; Gagliardi, C. A.; Garand, D.; Geurts, F.; Gibson, A.; Girard, M.; Greiner, L.; Grosnick, D.; Gunarathne, D. S.; Guo, Y.; Gupta, A.; Gupta, S.; Guryn, W.; Hamad, A.; Hamed, A.; Han, L.-X.; Haque, R.; Harris, J. W.; Heppelmann, S.; Hirsch, A.; Hoffmann, G. W.; Hofman, D. J.; Horvat, S.; Huang, B.; Huang, X.; Huang, H. Z.; Huck, P.; Humanic, T. J.; Igo, G.; Jacobs, W. W.; Jang, H.; Judd, E. G.; Kabana, S.; Kalinkin, D.; Kang, K.; Kauder, K.; Ke, H. W.; Keane, D.; Kechechyan, A.; Khan, Z. H.; Kikola, D. P.; Kisel, I.; Kisiel, A.; Klein, S. R.; Koetke, D. D.; Kollegger, T.; Kosarzewski, L. K.; Kotchenda, L.; Kraishan, A. F.; Kravtsov, P.; Krueger, K.; Kulakov, I.; Kumar, L.; Kycia, R. A.; Lamont, M. A. C.; Landgraf, J. M.; Landry, K. D.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, J. H.; Li, Z. M.; Li, X.; Li, W.; Li, Y.; Li, X.; Li, C.; Lisa, M. A.; Liu, F.; Ljubicic, T.; Llope, W. J.; Lomnitz, M.; Longacre, R. S.; Luo, X.; Ma, G. L.; Ma, R. M.; Ma, Y. G.; Magdy, N.; Mahapatra, D. P.; Majka, R.; Manion, A.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; McDonald, D.; Minaev, N. G.; Mioduszewski, S.; Mohanty, B.; Mondal, M. M.; Morozov, D. A.; Mustafa, M. K.; Nandi, B. K.; Nasim, Md.; Nayak, T. K.; Nigmatkulov, G.; Nogach, L. V.; Noh, S. Y.; Novak, J.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Oh, K.; Okorokov, V.; Olvitt, D. L.; Page, B. S.; Pan, Y. X.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Pawlik, B.; Pei, H.; Perkins, C.; Pile, P.; Planinic, M.; Pluta, J.; Poljak, N.; Poniatowska, K.; Porter, J.; Poskanzer, A. M.; Pruthi, N. K.; Przybycien, M.; Putschke, J.; Qiu, H.; Quintero, A.; Ramachandran, S.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Roy, A.; Ruan, L.; Rusnak, J.; Rusnakova, O.; Sahoo, N. R.; Sahu, P. K.; Sakrejda, I.; Salur, S.; Sandacz, A.; Sandweiss, J.; Sarkar, A.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmidke, W. B.; Schmitz, N.; Seger, J.; Seyboth, P.; Shah, N.; Shahaliev, E.; Shanmuganathan, P. V.; Shao, M.; Sharma, B.; Shen, W. Q.; Shi, S. S.; Shou, Q. Y.; Sichtermann, E. P.; Simko, M.; Skoby, M. J.; Smirnov, N.; Smirnov, D.; Solanki, D.; Song, L.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Sumbera, M.; Summa, B. J.; Sun, X. M.; Sun, Z.; Sun, Y.; Sun, X.; Surrow, B.; Svirida, D. N.; Szelezniak, M. A.; Takahashi, J.; Tang, Z.; Tang, A. H.; Tarnowsky, T.; Tawfik, A. N.; Thomas, J. H.; Timmins, A. R.; Tlusty, D.; Tokarev, M.; Trentalange, S.; Tribble, R. E.; Tribedy, P.; Tripathy, S. K.; Trzeciak, B. A.; Tsai, O. D.; Turnau, J.; Ullrich, T.; Underwood, D. G.; Upsal, I.; Van Buren, G.; van Nieuwenhuizen, G.; Vandenbroucke, M.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Vertesi, R.; Videbæk, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Vossen, A.; Wang, J. S.; Wang, X. L.; Wang, Y.; Wang, H.; Wang, F.; Wang, G.; Webb, G.; Webb, J. C.; Wen, L.; Westfall, G. D.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xiao, Z.; Xie, W.; Xin, K.; Xu, N.; Xu, Z.; Xu, H.; Xu, Y.; Xu, Q. H.; Yan, W.; Yang, Y.; Yang, C.; Yang, Y.; Ye, Z.; Yepes, P.; Yi, L.; Yip, K.; Yoo, I.-K.; Yu, N.; Zbroszczyk, H.; Zha, W.; Zhang, X. P.; Zhang, Z. P.; Zhang, J. B.; Zhang, J. L.; Zhang, Y.; Zhang, S.; Zhao, F.; Zhao, J.; Zhong, C.; Zhu, Y. H.; Zhu, X.; Zoulkarneeva, Y.; Zyzak, M.; STAR Collaboration

2016-08-01

Balance functions have been measured in terms of relative pseudorapidity (Δ η ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider from Au + Au collisions at √{sNN}=7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at √{sNN}=2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). The narrowing of the balance function in central collisions at √{sNN}=7.7 GeV implies that a QGP is still being created at this relatively low energy.

Conceptual design of hollow electron lenses for beam halo control in the Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stancari, Giulio; Previtali, Valentina; Valishev, Alexander

Collimation with hollow electron beams is a technique for halo control in high-power hadron beams. It is based on an electron beam (possibly pulsed or modulated in intensity) guided by strong axial magnetic fields which overlaps with the circulating beam in a short section of the ring. The concept was tested experimentally at the Fermilab Tevatron collider using a hollow electron gun installed in one of the Tevatron electron lenses. We are proposing a conceptual design for applying this technique to the Large Hadron Collider at CERN. A prototype hollow electron gun for the LHC was built and tested. Themore » expected performance of the hollow electron beam collimator was based on Tevatron experiments and on numerical tracking simulations. Halo removal rates and enhancements of halo diffusivity were estimated as a function of beam and lattice parameters. Proton beam core lifetimes and emittance growth rates were checked to ensure that undesired effects were suppressed. Hardware specifications were based on the Tevatron devices and on preliminary engineering integration studies in the LHC machine. Required resources and a possible timeline were also outlined, together with a brief discussion of alternative halo-removal schemes and of other possible uses of electron lenses to improve the performance of the LHC.« less

Beam-energy dependence of charge balance functions from Au + Au collisions at energies available at the BNL Relativistic Heavy Ion Collider

DOE PAGES

Adamczyk, L.; Adkins, J. K.; Agakishiev, G.; ...

2016-08-16

Balance functions have been measured in terms of relative pseudorapidity ( Δη ) for charged particle pairs at the BNL Relativistic Heavy Ion Collider (RHIC) from Au + Au collisions atmore » $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV to 200 GeV using the STAR detector. These results are compared with balance functions measured at the CERN Large Hadron Collider from Pb + Pb collisions at $$\\sqrt{s}$$$_{NN}$$ = 2.76 TeV by the ALICE Collaboration. The width of the balance function decreases as the collisions become more central and as the beam energy is increased. In contrast, the widths of the balance functions calculated using shuffled events show little dependence on centrality or beam energy and are larger than the observed widths. Balance function widths calculated using events generated by UrQMD are wider than the measured widths in central collisions and show little centrality dependence. The measured widths of the balance functions in central collisions are consistent with the delayed hadronization of a deconfined quark gluon plasma (QGP). Finally, the narrowing of the balance function in central collisions at $$\\sqrt{s}$$$_{NN}$$ = 7.7 GeV implies that a QGP is still being created at this relatively low energy.« less

Improved formalism for precision Higgs coupling fits

NASA Astrophysics Data System (ADS)

Barklow, Tim; Fujii, Keisuke; Jung, Sunghoon; Karl, Robert; List, Jenny; Ogawa, Tomohisa; Peskin, Michael E.; Tian, Junping

2018-03-01

Future e+e- colliders give the promise of model-independent determinations of the couplings of the Higgs boson. In this paper, we present an improved formalism for extracting Higgs boson couplings from e+e- data, based on the effective field theory description of corrections to the Standard Model. We apply this formalism to give projections of Higgs coupling accuracies for stages of the International Linear Collider and for other proposed e+e- colliders.

Design of a 6 TeV muon collider

DOE PAGES

Wang, M-H.; Nosochkov, Y.; Cai, Y.; ...

2016-09-09

Here, a preliminary design of a muon collider ring with the center of mass (CM) energy of 6 TeV is presented. The ring circumference is 6.3 km, and themore » $$\\beta$$ functions at collision point are 1 cm in each plane. The ring linear optics, the non-linear chromaticity compensation in the Interaction Region (IR), and the additional non-linear orthogonal correcting knobs are described. Magnet specifications are based on the maximum pole-tip field of 20T in dipoles and 15T in quadrupoles. Careful compensation of the non-linear chromatic and amplitude dependent effects provide a sufficiently large dynamic aperture for the momentum range of up to $$\\pm$$0.5% without considering magnet errors.« less

Pulse-by-pulse energy measurement at the Stanford Linear Collider

NASA Astrophysics Data System (ADS)

Blaylock, G.; Briggs, D.; Collins, B.; Petree, M.

1992-01-01

The Stanford Linear Collider (SLC) collides a beam of electrons and positrons at 92 GeV. It is the first colliding linac, and produces Z(sup 0) particles for High-Energy Physics measurements. The energy of each beam must be measured to one part in 10(exp 4) on every collision (120 Hz). An Energy Spectrometer in each beam line after the collision produces two stripes of high-energy synchrotron radiation with critical energy of a few MeV. The distance between these two stripes at an imaging plane measures the beam energy. The Wire-Imaging Synchrotron Radiation Detector (WISRD) system comprises a novel detector, data acquisition electronics, readout, and analysis. The detector comprises an array of wires for each synchrotron stripe. The electronics measure secondary emission charge on each wire of each array. A Macintosh II (using THINK C, THINK Class Library) and DSP coprocessor (using ANSI C) acquire and analyze the data, and display and report the results for SLC operation.

Preparation of a primary argon beam for the CERN fixed target physics.

PubMed

Küchler, D; O'Neil, M; Scrivens, R; Thomae, R

2014-02-01

The fixed target experiment NA61 in the North Area of the Super Proton Synchrotron is studying phase transitions in strongly interacting matter. Up to now they used the primary beams available from the CERN accelerator complex (protons and lead ions) or fragmented beams created from the primary lead ion beam. To explore a wider range of energies and densities a request was made to provide primary argon and xenon beams. This paper describes the results of the setting up and 10 week test run of the Ar(11+) beam from the 14.5 GHz ECR ion source and the linear accelerator (Linac3) at CERN.

Linear polarization of gluons and photons in unpolarized collider experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pisano, Cristian; Boer, Daniël; Brodsky, Stanley J.

2013-10-01

We study azimuthal asymmetries in heavy quark pair production in unpolarized electron-proton and proton-proton collisions, where the asymmetries originate from the linear polarization of gluons inside unpolarized hadrons. We provide cross section expressions and study the maximal asymmetries allowed by positivity, for both charm and bottom quark pair production. The upper bounds on the asymmetries are shown to be very large depending on the transverse momentum of the heavy quarks, which is promising especially for their measurements at a possible future Electron-Ion Collider or a Large Hadron electron Collider. We also study the analogous processes and asymmetries in muon pairmore » production as a means to probe linearly polarized photons inside unpolarized protons. For increasing invariant mass of the muon pair the asymmetries become very similar to the heavy quark pair ones. Finally, we discuss the process dependence of the results that arises due to differences in color flow and address the problem with factorization in case of proton-proton collisions.« less

A free-jet Hg target operating in a high magnetic field intersecting a high-power proton beam

NASA Astrophysics Data System (ADS)

Graves, Van; Spampinato, Philip; Gabriel, Tony; Kirk, Harold; Simos, Nicholas; Tsang, Thomas; McDonald, Kirk; Peter Titus; Fabich, Adrian; Haseroth, Helmut; Lettry, Jacques

2006-06-01

A proof-of-principal experiment to investigate the interaction of a proton beam, high magnetic field, and high-Z target is planned to take place at CERN in early 2007. This experiment is part of the Muon Collider Collaboration, with participants from Brookhaven National Laboratory, Princeton University, Massachusetts Institute Of Technology, European Organization for Nuclear Research-CERN, Rutherford Appleton Laboratory, and Oak Ridge National Laboratory. An unconstrained mercury jet target system that interacts with a high power (1 MW) proton beam in a high magnetic field (15 T) is being designed. The Hg jet diameter is 1-cm with a velocity up to 20 m/s. A laser optical diagnostic system will be incorporated into the target design to permit observation of the dispersal of the jet resulting from interaction with a 24 GeV proton beam with up to 20×1012 ppp. The target system includes instruments for sensing mercury vapor, temperature, flow rate, and sump tank level, and the means to position the jet relative to the magnetic axis of a solenoid and the proton beam. The design considerations for the system include all issues dealing with safely handling approximately 23 l of Hg, transporting the target system and the mercury to CERN, decommissioning the experiment, and returning the mildly activated equipment and Hg to the US.

A free-jet Hg target operating in a high magnetic field intersecting a high-power proton beam

NASA Astrophysics Data System (ADS)

Van Graves; Spampinato, Philip; Gabriel, Tony; Kirk, Harold; Simos, Nicholas; Tsang, Thomas; McDonald, Kirk; Peter Titus; Fabich, Adrian; Haseroth, Helmut; Lettry, Jacques

2006-06-01

A proof-of-principal experiment to investigate the interaction of a proton beam, high magnetic field, and high- Z target is planned to take place at CERN in early 2007. This experiment is part of the Muon Collider Collaboration, with participants from Brookhaven National Laboratory, Princeton University, Massachusetts Institute Of Technology, European Organization for Nuclear Research-CERN, Rutherford Appleton Laboratory, and Oak Ridge National Laboratory. An unconstrained mercury jet target system that interacts with a high power (1 MW) proton beam in a high magnetic field (15 T) is being designed. The Hg jet diameter is 1-cm with a velocity up to 20 m/s. A laser optical diagnostic system will be incorporated into the target design to permit observation of the dispersal of the jet resulting from interaction with a 24 GeV proton beam with up to 20×10 12 ppp. The target system includes instruments for sensing mercury vapor, temperature, flow rate, and sump tank level, and the means to position the jet relative to the magnetic axis of a solenoid and the proton beam. The design considerations for the system include all issues dealing with safely handling approximately 23 l of Hg, transporting the target system and the mercury to CERN, decommissioning the experiment, and returning the mildly activated equipment and Hg to the US.

SHiP: a new facility with a dedicated detector to search for new neutral particles and studying tau neutrino properties

NASA Astrophysics Data System (ADS)

Shevchenko, V.

2017-12-01

SHiP (Search for Hidden Particles) is a new general purpose fixed target facility, whose Technical Proposal has been recently reviewed by the CERN SPS Committee and by the CERN Research Board. The two boards recommended that the experiment proceeds further to a Comprehensive Design phase in the context of the new CERNWorking group "Physics Beyond Colliders", aiming at presenting a CERN strategy for the European Strategy meeting of 2019. In the initial phase of SHiP, the 400 GeV proton beam extracted from the SPS will be dumped on a heavy target with the aim of integrating 2×1020 pot in 5 years. A dedicated detector, based on a long vacuum tank followed by a spectrometer and particle identification detectors, will allow probing a variety of models with light long-lived exotic particles and masses below O(10) GeV/c2. The main focus will be the physics of the so-called Hidden Portals, i.e. search for Dark Photons, Light scalars and pseudo-scalars, and Heavy Neutrinos. The sensitivity to Heavy Neutrinos will allow for the first time to probe, in the mass range between the kaon and the charm meson mass, a coupling range for which Baryogenesis and active neutrino masses could also be explained. Another dedicated detector will allow the study of neutrino cross-sections and angular distributions.

Testing the scalar sector of the twin Higgs model at colliders

NASA Astrophysics Data System (ADS)

Chacko, Zackaria; Kilic, Can; Najjari, Saereh; Verhaaren, Christopher B.

2018-03-01

We consider mirror twin Higgs models in which the breaking of the global symmetry is realized linearly. In this scenario, the radial mode in the Higgs potential is present in the spectrum and constitutes a second portal between the twin and SM sectors. We show that a study of the properties of this particle at colliders, when combined with precision measurements of the light Higgs, can be used to overdetermine the form of the scalar potential, thereby confirming that it possesses an enhanced global symmetry as dictated by the twin Higgs mechanism. We find that, although the reach of the LHC for this state is limited, future linear colliders will be able to explore a significant part of the preferred parameter space, allowing the possibility of directly testing the twin Higgs framework.

Design study of an optical cavity for a future photon collider at ILC

NASA Astrophysics Data System (ADS)

Klemz, G.; Mönig, K.; Will, I.

2006-08-01

Hard photons well above 100 GeV have to be generated in a future photon collider which essentially will be based on the infrastructure of the planned International Linear Collider (ILC). The energy of near-infrared laser photons will be boosted by Compton backscattering against a high-energy relativistic electron beam. For high effectiveness, a very powerful laser system is required that exceeds today's state-of-the-art capabilities. In this paper a design of an auxiliary passive cavity is discussed that resonantly enhances the peak-power of the laser. The properties and prospects of such a cavity are addressed on the basis of the specifications for the European TeV Energy Superconducting Linear Accelerator (TESLA) proposal. Those of the ILC are expected to be similar.

Zeroth-order design report for the next linear collider. Volume 1

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raubenheimer, T.O.

1996-05-01

This Zeroth Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The design presented here is not fully engineered in any sense, but to be assured that themore » NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume one covers the following: the introduction; electron source; positron source; NLC damping rings; bunch compressors and prelinac; low-frequency linacs and compressors; main linacs; design and dynamics; and RF systems for main linacs.« less

Improved formalism for precision Higgs coupling fits

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barklow, Tim; Fujii, Keisuke; Jung, Sunghoon

Future e +e – colliders give the promise of model-independent determinations of the couplings of the Higgs boson. In this paper, we present an improved formalism for extracting Higgs boson couplings from e +e – data, based on the effective field theory description of corrections to the Standard Model. Lastly, we apply this formalism to give projections of Higgs coupling accuracies for stages of the International Linear Collider and for other proposed e +e – colliders.

Improved formalism for precision Higgs coupling fits

DOE PAGES

Barklow, Tim; Fujii, Keisuke; Jung, Sunghoon; ...

2018-03-20

Future e +e – colliders give the promise of model-independent determinations of the couplings of the Higgs boson. In this paper, we present an improved formalism for extracting Higgs boson couplings from e +e – data, based on the effective field theory description of corrections to the Standard Model. Lastly, we apply this formalism to give projections of Higgs coupling accuracies for stages of the International Linear Collider and for other proposed e +e – colliders.

High fidelity 3-dimensional models of beam-electron cloud interactions in circular accelerators

NASA Astrophysics Data System (ADS)

Feiz Zarrin Ghalam, Ali

Electron cloud is a low-density electron profile created inside the vacuum chamber of circular machines with positively charged beams. Electron cloud limits the peak current of the beam and degrades the beams' quality through luminosity degradation, emittance growth and head to tail or bunch to bunch instability. The adverse effects of electron cloud on long-term beam dynamics becomes more and more important as the beams go to higher and higher energies. This problem has become a major concern in many future circular machines design like the Large Hadron Collider (LHC) under construction at European Center for Nuclear Research (CERN). Due to the importance of the problem several simulation models have been developed to model long-term beam-electron cloud interaction. These models are based on "single kick approximation" where the electron cloud is assumed to be concentrated at one thin slab around the ring. While this model is efficient in terms of computational costs, it does not reflect the real physical situation as the forces from electron cloud to the beam are non-linear contrary to this model's assumption. To address the existing codes limitation, in this thesis a new model is developed to continuously model the beam-electron cloud interaction. The code is derived from a 3-D parallel Particle-In-Cell (PIC) model (QuickPIC) originally used for plasma wakefield acceleration research. To make the original model fit into circular machines environment, betatron and synchrotron equations of motions have been added to the code, also the effect of chromaticity, lattice structure have been included. QuickPIC is then benchmarked against one of the codes developed based on single kick approximation (HEAD-TAIL) for the transverse spot size of the beam in CERN-LHC. The growth predicted by QuickPIC is less than the one predicted by HEAD-TAIL. The code is then used to investigate the effect of electron cloud image charges on the long-term beam dynamics, particularly on the transverse tune shift of the beam at CERN Super Proton Synchrotron (SPS) ring. The force from the electron cloud image charges on the beam cancels the force due to cloud compression formed on the beam axis and therefore the tune shift is mainly due to the uniform electron cloud density. (Abstract shortened by UMI.)

Direct-photon spectrum and elliptic flow produced from Pb+Pb collisions at √{sN N}=2.76 TeV at the CERN Large Hadron Collider within an integrated hydrokinetic model

NASA Astrophysics Data System (ADS)

Naboka, V. Yu.; Sinyukov, Yu. M.; Zinovjev, G. M.

2018-05-01

The photon transverse momentum spectrum and its anisotropy from Pb+Pb collisions at the CERN Large Hadron Collider energy √{sN N}=2.76 TeV are investigated within the integrated hydrokinetic model (iHKM). Photon production is accumulated from the different processes at the various stages of relativistic heavy ion collisions: from the primary hard photons of very early stage of parton collisions to the thermal photons from equilibrated quark-gluon and hadron gas stages. Along the way a hadronic medium evolution is treated in two distinct, in a sense opposite, approaches: chemically equilibrated and chemically frozen system expansion. Studying the centrality dependence of the results obtained allows us to conclude that a relatively strong transverse momentum anisotropy of thermal radiation is suppressed by prompt photon emission which is an isotropic. We find out that this effect is getting stronger as centrality increases because of the simultaneous increase in the relative contribution of prompt photons in the soft part of the spectra. The substantial results obtained in iHKM with nonzero viscosity (η /s =0.08 ) for photon spectra and v2 coefficients are mostly within the error bars of experimental data, but there is some systematic underestimation of both observables for the near central events. We claim that a situation could be significantly improved if an additional photon radiation that accompanies the presence of a deconfined environment is included. Since a matter of a space-time layer where hadronization takes place is actively involved in anisotropic transverse flow, both positive contributions to the spectra and v2 are considerable, albeit such an argument needs further research and elaboration.

Gaseous Electron Multiplier (GEM) Detectors

NASA Astrophysics Data System (ADS)

Gnanvo, Kondo

2017-09-01

Gaseous detectors have played a pivotal role as tracking devices in the field of particle physics experiments for the last fifty years. Recent advances in photolithography and micro processing techniques have enabled the transition from Multi Wire Proportional Chambers (MWPCs) and Drift Chambers to a new family of gaseous detectors refer to as Micro Pattern Gaseous Detectors (MPGDs). MPGDs combine the basic gas amplification principle with micro-structure printed circuits to provide detectors with excellent spatial and time resolution, high rate capability, low material budget and high radiation tolerance. Gas Electron Multiplier (GEMs) is a well-established MPGD technology invented by F. Sauli at CERN in 1997 and deployed various high energy physics (HEP) and nuclear NP experiment for tracking systems of current and future NP experiments. GEM detector combines an exceptional high rate capability (1 MHz / mm2) and robustness against harsh radiation environment with excellent position and timing resolution performances. Recent breakthroughs over the past decade have allowed the possibility for large area GEMs, making them cost effective and high-performance detector candidates to play pivotal role in current and future particle physics experiments. After a brief introduction of the basic principle of GEM technology, I will give a brief overview of the GEM detectors used in particle physics experiments over the past decades and especially in the NP community at Thomas Jefferson National Laboratory (JLab) and Brookhaven National Laboratory (BNL). I will follow by a review of state of the art of the new GEM development for the next generation of colliders such as Electron Ion Collider (EIC) or High Luminosity LHC and future Nuclear Physics experiments. I will conclude with a presentation of the CERN-based RD51 collaboration established in 2008 and its major achievements regarding technological developments and applications of MPGDs.

Study of cosmic ray events with high muon multiplicity using the ALICE detector at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Collaboration: ALICE Collaboration

2016-01-01

ALICE is one of four large experiments at the CERN Large Hadron Collider near Geneva, specially designed to study particle production in ultra-relativistic heavy-ion collisions. Located 52 meters underground with 28 meters of overburden rock, it has also been used to detect muons produced by cosmic ray interactions in the upper atmosphere. In this paper, we present the multiplicity distribution of these atmospheric muons and its comparison with Monte Carlo simulations. This analysis exploits the large size and excellent tracking capability of the ALICE Time Projection Chamber. A special emphasis is given to the study of high multiplicity events containingmore » more than 100 reconstructed muons and corresponding to a muon areal density ρ{sub μ} > 5.9 m{sup −2}. Similar events have been studied in previous underground experiments such as ALEPH and DELPHI at LEP. While these experiments were able to reproduce the measured muon multiplicity distribution with Monte Carlo simulations at low and intermediate multiplicities, their simulations failed to describe the frequency of the highest multiplicity events. In this work we show that the high multiplicity events observed in ALICE stem from primary cosmic rays with energies above 10{sup 16} eV and that the frequency of these events can be successfully described by assuming a heavy mass composition of primary cosmic rays in this energy range. The development of the resulting air showers was simulated using the latest version of QGSJET to model hadronic interactions. This observation places significant constraints on alternative, more exotic, production mechanisms for these events.« less

Characteristic W-ino signals in a linear collider from anomaly mediated supersymmetry breaking

NASA Astrophysics Data System (ADS)

Ghosh, Dilip Kumar; Kundu, Anirban; Roy, Probir; Roy, Sourov

2001-12-01

Though the minimal model of anomaly-mediated supersymmetry breaking has been significantly constrained by recent experimental and theoretical work, there are still allowed regions of the parameter space for moderate to large values of tan β. We show that these regions will be comprehensively probed in a s=1 TeV e+e- linear collider. Diagnostic signals to this end are studied by zeroing in on a unique and distinct feature of a large class of models in this genre: a neutral W-ino-like lightest supersymmetric particle closely degenerate in mass with a W-ino-like chargino. The pair production processes e+e--->e+/-Le-/+L, e+/-Re-/+R, e+/-Le-/+R, ν~νbar, χ~01χ~02, χ~02χ~02 are all considered at s=1 TeV corresponding to the proposed DESY TEV Energy Superconducting Linear Accelerator linear collider in two natural categories of mass ordering in the sparticle spectra. The signals analyzed comprise multiple combinations of fast charged leptons (any of which can act as the trigger) plus displaced vertices XD (any of which can be identified by a heavy ionizing track terminating in the detector) and/or associated soft pions with characteristic momentum distributions.

Impact of detector simulation in particle physics collider experiments

DOE Office of Scientific and Technical Information (OSTI.GOV)

Elvira, V. Daniel

Through the last three decades, precise simulation of the interactions of particles with matter and modeling of detector geometries has proven to be of critical importance to the success of the international high-energy physics experimental programs. For example, the detailed detector modeling and accurate physics of the Geant4-based simulation software of the CMS and ATLAS particle physics experiments at the European Center of Nuclear Research (CERN) Large Hadron Collider (LHC) was a determinant factor for these collaborations to deliver physics results of outstanding quality faster than any hadron collider experiment ever before. This review article highlights the impact of detectormore » simulation on particle physics collider experiments. It presents numerous examples of the use of simulation, from detector design and optimization, through software and computing development and testing, to cases where the use of simulation samples made a difference in the accuracy of the physics results and publication turnaround, from data-taking to submission. It also presents the economic impact and cost of simulation in the CMS experiment. Future experiments will collect orders of magnitude more data, taxing heavily the performance of simulation and reconstruction software for increasingly complex detectors. Consequently, it becomes urgent to find solutions to speed up simulation software in order to cope with the increased demand in a time of flat budgets. The study ends with a short discussion on the potential solutions that are being explored, by leveraging core count growth in multicore machines, using new generation coprocessors, and re-engineering of HEP code for concurrency and parallel computing.« less

Impact of detector simulation in particle physics collider experiments

DOE PAGES

Elvira, V. Daniel

2017-06-01

Through the last three decades, precise simulation of the interactions of particles with matter and modeling of detector geometries has proven to be of critical importance to the success of the international high-energy physics experimental programs. For example, the detailed detector modeling and accurate physics of the Geant4-based simulation software of the CMS and ATLAS particle physics experiments at the European Center of Nuclear Research (CERN) Large Hadron Collider (LHC) was a determinant factor for these collaborations to deliver physics results of outstanding quality faster than any hadron collider experiment ever before. This review article highlights the impact of detectormore » simulation on particle physics collider experiments. It presents numerous examples of the use of simulation, from detector design and optimization, through software and computing development and testing, to cases where the use of simulation samples made a difference in the accuracy of the physics results and publication turnaround, from data-taking to submission. It also presents the economic impact and cost of simulation in the CMS experiment. Future experiments will collect orders of magnitude more data, taxing heavily the performance of simulation and reconstruction software for increasingly complex detectors. Consequently, it becomes urgent to find solutions to speed up simulation software in order to cope with the increased demand in a time of flat budgets. The study ends with a short discussion on the potential solutions that are being explored, by leveraging core count growth in multicore machines, using new generation coprocessors, and re-engineering of HEP code for concurrency and parallel computing.« less

Impact of detector simulation in particle physics collider experiments

NASA Astrophysics Data System (ADS)

Daniel Elvira, V.

2017-06-01

Through the last three decades, accurate simulation of the interactions of particles with matter and modeling of detector geometries has proven to be of critical importance to the success of the international high-energy physics (HEP) experimental programs. For example, the detailed detector modeling and accurate physics of the Geant4-based simulation software of the CMS and ATLAS particle physics experiments at the European Center of Nuclear Research (CERN) Large Hadron Collider (LHC) was a determinant factor for these collaborations to deliver physics results of outstanding quality faster than any hadron collider experiment ever before. This review article highlights the impact of detector simulation on particle physics collider experiments. It presents numerous examples of the use of simulation, from detector design and optimization, through software and computing development and testing, to cases where the use of simulation samples made a difference in the precision of the physics results and publication turnaround, from data-taking to submission. It also presents estimates of the cost and economic impact of simulation in the CMS experiment. Future experiments will collect orders of magnitude more data with increasingly complex detectors, taxing heavily the performance of simulation and reconstruction software. Consequently, exploring solutions to speed up simulation and reconstruction software to satisfy the growing demand of computing resources in a time of flat budgets is a matter that deserves immediate attention. The article ends with a short discussion on the potential solutions that are being considered, based on leveraging core count growth in multicore machines, using new generation coprocessors, and re-engineering HEP code for concurrency and parallel computing.

Optimization of detectors for the ILC

NASA Astrophysics Data System (ADS)

Suehara, Taikan; ILD Group; SID Group

2016-04-01

International Linear Collider (ILC) is a next-generation e+e- linear collider to explore Higgs, Beyond-Standard-Models, top and electroweak particles with great precision. We are optimizing our two detectors, International Large Detector (ILD) and Silicon Detector (SiD) to maximize the physics reach expected in ILC with reasonable detector cost and good reliability. The optimization study on vertex detectors, main trackers and calorimeters is underway. We aim to conclude the optimization to establish final designs in a few years, to finish detector TDR and proposal in reply to expected ;green sign; of the ILC project.

Staging optics considerations for a plasma wakefield acceleration linear collider

NASA Astrophysics Data System (ADS)

Lindstrøm, C. A.; Adli, E.; Allen, J. M.; Delahaye, J. P.; Hogan, M. J.; Joshi, C.; Muggli, P.; Raubenheimer, T. O.; Yakimenko, V.

2016-09-01

Plasma wakefield acceleration offers acceleration gradients of several GeV/m, ideal for a next-generation linear collider. The beam optics requirements between plasma cells include injection and extraction of drive beams, matching the main beam beta functions into the next cell, canceling dispersion as well as constraining bunch lengthening and chromaticity. To maintain a high effective acceleration gradient, this must be accomplished in the shortest distance possible. A working example is presented, using novel methods to correct chromaticity, as well as scaling laws for a high energy regime.

Physics at the [Formula: see text] linear collider.

PubMed

Moortgat-Pick, G; Baer, H; Battaglia, M; Belanger, G; Fujii, K; Kalinowski, J; Heinemeyer, S; Kiyo, Y; Olive, K; Simon, F; Uwer, P; Wackeroth, D; Zerwas, P M; Arbey, A; Asano, M; Bagger, J; Bechtle, P; Bharucha, A; Brau, J; Brümmer, F; Choi, S Y; Denner, A; Desch, K; Dittmaier, S; Ellwanger, U; Englert, C; Freitas, A; Ginzburg, I; Godfrey, S; Greiner, N; Grojean, C; Grünewald, M; Heisig, J; Höcker, A; Kanemura, S; Kawagoe, K; Kogler, R; Krawczyk, M; Kronfeld, A S; Kroseberg, J; Liebler, S; List, J; Mahmoudi, F; Mambrini, Y; Matsumoto, S; Mnich, J; Mönig, K; Mühlleitner, M M; Pöschl, R; Porod, W; Porto, S; Rolbiecki, K; Schmitt, M; Serpico, P; Stanitzki, M; Stål, O; Stefaniak, T; Stöckinger, D; Weiglein, G; Wilson, G W; Zeune, L; Moortgat, F; Xella, S; Bagger, J; Brau, J; Ellis, J; Kawagoe, K; Komamiya, S; Kronfeld, A S; Mnich, J; Peskin, M; Schlatter, D; Wagner, A; Yamamoto, H

A comprehensive review of physics at an [Formula: see text] linear collider in the energy range of [Formula: see text] GeV-3 TeV is presented in view of recent and expected LHC results, experiments from low-energy as well as astroparticle physics. The report focusses in particular on Higgs-boson, top-quark and electroweak precision physics, but also discusses several models of beyond the standard model physics such as supersymmetry, little Higgs models and extra gauge bosons. The connection to cosmology has been analysed as well.

GARLIC: GAmma Reconstruction at a LInear Collider experiment

NASA Astrophysics Data System (ADS)

Jeans, D.; Brient, J.-C.; Reinhard, M.

2012-06-01

The precise measurement of hadronic jet energy is crucial to maximise the physics reach of a future Linear Collider. An important ingredient required to achieve this is the efficient identification of photons within hadronic showers. One configuration of the ILD detector concept employs a highly granular silicon-tungsten sampling calorimeter to identify and measure photons, and the GARLIC algorithm described in this paper has been developed to identify photons in such a calorimeter. We describe the algorithm and characterise its performance using events fully simulated in a model of the ILD detector.

Construction and performance of a silicon photomultiplier/extruded scintillator tail-catcher and muon-tracker

NASA Astrophysics Data System (ADS)

Adloff, C.; Blaha, J.; Blaising, J.-J.; Drancourt, C.; Espargilière, A.; Gaglione, R.; Geffroy, N.; Karyotakis, Y.; Prast, J.; Vouters, G.; Bilki, B.; Francis, K.; Repond, J.; Smith, J.; Xia, L.; Baldolemar, E.; Li, J.; Park, S. T.; Sosebee, M.; White, A. P.; Yu, J.; Buanes, T.; Eigen, G.; Mikami, Y.; Watson, N. K.; Mavromanolakis, G.; Thomson, M. A.; Ward, D. R.; Yan, W.; Benchekroun, D.; Hoummada, A.; Khoulaki, Y.; Benyamna, M.; Cârloganu, C.; Fehr, F.; Gay, P.; Manen, S.; Royer, L.; Blazey, G. C.; Boona, S.; Chakraborty, D.; Dyshkant, A.; Hedin, D.; Lima, J. G. R.; Powell, J.; Rykalin, V.; Scurti, N.; Smith, M.; Tran, N.; Zutshi, V.; Hostachy, J.-Y.; Morin, L.; Cornett, U.; David, D.; Dietrich, J.; Falley, G.; Gadow, K.; Göttlicher, P.; Günter, C.; Hermberg, B.; Karstensen, S.; Krivan, F.; Lucaci-Timoce, A.-I.; Lu, S.; Lutz, B.; Marchesini, I.; Morozov, S.; Morgunov, V.; Reinecke, M.; Sefkow, F.; Smirnov, P.; Terwort, M.; Vargas-Trevino, A.; Feege, N.; Garutti, E.; Eckert, P.; Kaplan, A.; Schultz-Coulon, H.-Ch; Shen, W.; Stamen, R.; Tadday, A.; Norbeck, E.; Onel, Y.; Wilson, G. W.; Kawagoe, K.; Uozumi, S.; Dauncey, P. D.; Magnan, A.-M.; Bartsch, V.; Wing, M.; Salvatore, F.; Calvo Alamillo, E.; Fouz, M.-C.; Puerta-Pelayo, J.; Bobchenko, B.; Chadeeva, M.; Danilov, M.; Epifantsev, A.; Markin, O.; Mizuk, R.; Novikov, E.; Rusinov, V.; Tarkovsky, E.; Kirikova, N.; Kozlov, V.; Soloviev, Y.; Buzhan, P.; Dolgoshein, B.; Ilyin, A.; Kantserov, V.; Kaplin, V.; Karakash, A.; Popova, E.; Smirnov, S.; Frey, A.; Kiesling, C.; Seidel, K.; Simon, F.; Soldner, C.; Weuste, L.; Bonis, J.; Bouquet, B.; Callier, S.; Cornebise, P.; Doublet, Ph; Dulucq, F.; Faucci Giannelli, M.; Fleury, J.; Li, H.; Martin-Chassard, G.; Richard, F.; de la Taille, Ch; Pöschl, R.; Raux, L.; Seguin-Moreau, N.; Wicek, F.; Anduze, M.; Boudry, V.; Brient, J.-C.; Jeans, D.; Mora de Freitas, P.; Musat, G.; Reinhard, M.; Ruan, M.; Videau, H.; Bulanek, B.; Zacek, J.; Cvach, J.; Gallus, P.; Havranek, M.; Janata, M.; Kvasnicka, J.; Lednicky, D.; Marcisovsky, M.; Polak, I.; Popule, J.; Tomasek, L.; Tomasek, M.; Ruzicka, P.; Sicho, P.; Smolik, J.; Vrba, V.; Zalesak, J.; Belhorma, B.; Ghazlane, H.; Takeshita, T.

2012-04-01

A prototype module for an International Linear Collider (ILC) detector was built, installed, and tested between 2006 and 2009 at CERN and Fermilab as part of the CALICE test beam program, in order to study the possibilities of extending energy sampling behind a hadronic calorimeter and to study the possibilities of providing muon tracking. The ``tail catcher/muon tracker'' (TCMT) is composed of 320 extruded scintillator strips (dimensions 1000 × 50 × 5 mm3) packaged in 16 one-meter square planes interleaved between steel plates. The scintillator strips were read out with wavelength shifting fibers and silicon photomultipliers. The planes were arranged with alternating horizontal and vertical strip orientations. Data were collected for muons and pions in the energy range 6 GeV to 80 GeV. Utilizing data taken in 2006, this paper describes the design and construction of the TCMT, performance characteristics, and a beam-based evaluation of the ability of the TCMT to improve hadronic energy resolution in a prototype ILC detector. For a typical configuration of an ILC detector with a coil situated outside a calorimeter system with a thickness of 5.5 nuclear interaction lengths, a TCMT would improve relative energy resolution by 6-16% for pions between 20 and 80 GeV.

The key particle and quark energy equality E W + E Z = E top

NASA Astrophysics Data System (ADS)

Mac Gregor, Malcolm H.

2017-11-01

Precision Tevatron and Linear Hadron Collider measurements at Fermilab and CERN have revealed the numerically accurate mass equality W + Z = t. This equality between two gauge bosons ( gb) and the top quark t is only valid if reinterpreted as an energy equality, where E = mc 2, since energy is a shared property of particles and quarks. The experimental data indicate that the LHC particle excitation energy is quantized in the form of gauge boson energy packets E gb , which are created by factor-of-137 proton-quark energy increases denoted as α- boosts, where α 1/137 is the fine structure constant. These α-boosts occur during the rare head-on quark-quark collisions in the proton beams. The α-boost energy quantization mechanism also occurs in low-energy electron-positron boson and fermion particle production channels, where it generates E b and E f energy packets. These α-boost energy channels link together coherently, as demonstrated by the accurate top quark energy equation E top = (18/α2) E electron. Particle production energy equations are derived which combine to create an overall energy pattern that accurately reproduces the energies of the ( u, d), s, c, b, t fermion constituent quarks, the µ and τ leptons, and the proton.

Design of a high power TM01 mode launcher optimized for manufacturing by milling

DOE Office of Scientific and Technical Information (OSTI.GOV)

Dal Forno, Massimo

2016-12-15

Recent research on high-gradient rf acceleration found that hard metals, such as hard copper and hard copper-silver, have lower breakdown rate than soft metals. Traditional high-gradient accelerating structures are manufactured with parts joined by high-temperature brazing. The high temperature used in brazing makes the metal soft; therefore, this process cannot be used to manufacture structures out of hard metal alloys. In order to build the structure with hard metals, the components must be designed for joining without high-temperature brazing. One method is to build the accelerating structures out of two halves, and join them by using a low-temperature technique, atmore » the symmetry plane along the beam axis. The structure has input and output rf power couplers. We use a TM01 mode launcher as a rf power coupler, which was introduced during the Next Linear Collider (NLC) work. The part of the mode launcher will be built in each half of the structure. This paper presents a novel geometry of a mode launcher, optimized for manufacturing by milling. The coupler was designed for the CERN CLIC working frequency f = 11.9942 GHz; the same geometry can be scaled to any other frequency.« less

Static beam-based alignment for the Ring-To-Main-Linac of the Compact Linear Collider

NASA Astrophysics Data System (ADS)

Han, Y.; Latina, A.; Ma, L.; Schulte, D.

2017-06-01

The Compact Linear Collider (CLIC) is a future multi-TeV collider for the post-Large Hadron Collider era. It features high-gradient acceleration and ultra-low emittance to achieve its ambitious goals of high collision energy and peak luminosity. Beam-based alignment (BBA) techniques are mandatory for CLIC to preserve the ultra-low emittances from the damping rings to the interaction point. In this paper, a detailed study of BBA techniques has been carried out for the entire 27 km long ``Ring-To-Main-Linac'' (RTML) section of the CLIC, to correct realistic static errors such as element position offsets, angle, magnetic strength and dynamic magnetic centre shifts. The correction strategy is proved to be very effective and leads to a relaxation of the pre-alignment tolerances for the component installation in the tunnel. This is the first time such a large scale and complex lattice has been corrected to match the design budgets. The techniques proposed could be applied to similarly sized facilities, such as the International Linear Collider, where a similar RTML section is used, or free-electron lasers, which, being equipped with linacs and bunch compressors, present challenges similar to those of the CLIC RTML. Moreover, a new technique is investigated for the emittance tuning procedure: the direct measurement of the interactions between the beams and a set of a few consecutive laser wires. The speed of this technique can be faster comparing to the traditional techniques based on emittance reconstructed from beam size measurements at several positions.

Preparation of a primary argon beam for the CERN fixed target physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Küchler, D., E-mail: detlef.kuchler@cern.ch; O’Neil, M.; Scrivens, R.

2014-02-15

The fixed target experiment NA61 in the North Area of the Super Proton Synchrotron is studying phase transitions in strongly interacting matter. Up to now they used the primary beams available from the CERN accelerator complex (protons and lead ions) or fragmented beams created from the primary lead ion beam. To explore a wider range of energies and densities a request was made to provide primary argon and xenon beams. This paper describes the results of the setting up and 10 week test run of the Ar{sup 11+} beam from the 14.5 GHz ECR ion source and the linear acceleratormore » (Linac3) at CERN.« less

Experimental Results Obtained with Air Liquide Cold Compression System: CERN LHC and SNS Projects

NASA Astrophysics Data System (ADS)

Delcayre, F.; Courty, J.-C.; Hamber, F.; Hilbert, B.; Monneret, E.; Toia, J.-L.

2006-04-01

Large scale collider facilities will make intensive use of superconducting magnets, operating below 2.0 K. This dictates high-capacity refrigeration systems operating below 2.0 K. These systems, making use of cryogenic centrifugal compressors in a series arrangement with room temperature screw compressors will be coupled to a refrigerator, providing a certain power at 4.5 K. A first Air Liquide Cold Compression System (CCS) unit was built and delivered to CERN in 2001. Installed at the beginning of 2002, it was commissioned and tested successfully during year 2002. A series of four sets of identical CCS were then tested in 2004. Another set of four cryogenic centrifugal compressors (CCC) has been delivered to Thomas Jefferson National Accelerator Facility (JLAB) for the Spallation Neutron Source (SNS) in 2002. These compressors were tested and commissioned from December 2004 to July 2005. The experimental results obtained with these systems will be presented and discussed: the characteristics of the CCC will be detailed. The principles of control for the CCC in series will be detailed.

Planck 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2010-06-02

Planck 2010 From the Planck Scale to the ElectroWeak Scale The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC.Topics to be discussed: Supersymmetry Supergravity & string phenomenology Extra dimensions Electroweak symmetry breaking LHC and Tevatron Physics Collider physics Flavor & neutrinos physics Astroparticle & cosmology Gravity & holography Strongly coupled physics & CFT Registration: registration will be open until May 1st.more » Registration fees amount to 150 CHF and cover the cost of the coffee breaks and the social dinner. Payment has to be made online. The deadline for registration has been postponed to May 7th. However, after May 3th, we shall not accept any talk request any more. The meeting will be partly supported by ° the Marie Curie Initial Training Network "UNILHC" PITN-GA-2009-23792, ° the ERC Advanced Grant "MassTeV" 226371, ° and the CERN-TH unit.« less

Planck 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Covi, Laura; Hasenkamp, J.

2010-06-02

Planck 2010 From the Planck Scale to the ElectroWeak Scale The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC.Topics to be discussed: Supersymmetry Supergravity & string phenomenology. Extra dimensions; Electroweak symmetry breaking; LHC and Tevatron Physics; Collider physics; Flavor & neutrinos physics Astroparticle & cosmology; Gravity & holography; BStrongly coupled physics & CFT. Registration: registration will be open until May 1st.more » Registration fees amount to 150 CHF and cover the cost of the coffee breaks and the social dinner. Payment has to be made online. The deadline for registration has been postponed to May 7th. However, after May 3th, we shall not accept any talk request any more. The meeting will be partly supported by; the Marie Curie Initial Training Network UNILHC PITN-GA-2009-23792; the ERC Advanced Grant "MassTeV" 226371; and the CERN-TH unit.« less

Planck 2010

DOE Office of Scientific and Technical Information (OSTI.GOV)

Murayama, Hitoshi

2010-06-02

Planck 2010 From the Planck Scale to the ElectroWeak Scale The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC.Topics to be discussed: SupersymmetrySupergravity & string phenomenology Extra dimensions Electroweak symmetry breaking LHC and Tevatron Physics Collider physics Flavor & neutrinos physics Astroparticle & cosmology Gravity & holography Strongly coupled physics & CFT Registration: registration will be open until May 1st. Registrationmore » fees amount to 150 CHF and cover the cost of the coffee breaks and the social dinner. Payment has to be made online. The deadline for registration has been postponed to May 7th. However, after May 3th, we shall not accept any talk request any more. The meeting will be partly supported by; the Marie Curie Initial Training Network "UNILHC" PITN-GA-2009-23792, the ERC Advanced Grant "MassTeV" 226371, and the CERN-TH unit.« less

Assembly Tests of the First Nb 3 Sn Low-Beta Quadrupole Short Model for the Hi-Lumi LHC

DOE PAGES

Pan, H.; Felice, H.; Cheng, D. W.; ...

2016-01-18

In preparation for the high-luminosity upgrade of the Large Hadron Collider (LHC), the LHC Accelerator Research Program (LARP) in collaboration with CERN is pursuing the development of MQXF: a 150-mm-aperture high-field Nb3Sn quadrupole magnet. Moreover, the development phase starts with the fabrication and test of several short models (1.2-m magnetic length) and will continue with the development of several long prototypes. All of them are mechanically supported using a shell-based support structure, which has been extensively demonstrated on several R&D models within LARP. The first short model MQXFS-AT has been assembled at LBNL with coils fabricated by LARP and CERN.more » In our paper, we summarize the assembly process and show how it relies strongly on experience acquired during the LARP 120-mm-aperture HQ magnet series. We also present comparison between strain gauges data and finite-element model analysis. Finally, we present the implication of the MQXFS-AT experience on the design of the long prototype support structure.« less

PREFACE: International Workshop on Discovery Physics at the LHC (Kruger2012)

NASA Astrophysics Data System (ADS)

Cleymans, Jean

2013-08-01

The second conference on 'Discovery Physics at the LHC' was held on 3-7 December 2012 at the Kruger Gate Hotel in South Africa. In total there were 110 participants from Armenia, Belgium, Brazil, Canada, Czech Republic, France, Germany, Greece, Israel, Italy, Norway, Poland, USA, Russia, Slovakia, Spain, Sweden, United Kingdom, Switzerland and South Africa. The latest results from the Large Hadron Collider, Brookhaven National Laboratory, Jefferson Laboratory and BABAR experiments, as well as the latest theoretical insights were presented. Set against the backdrop of the majestic Kruger National Park a very stimulating conference with many exchanges took place. The proceedings reflect the high standard of the conference. The financial contributions from the National Institute for Theoretical Physics (NITHeP), the SA-CERN programme, the UCT-CERN Research Centre, the University of Johannesburg, the University of the Witwatersrand and iThemba Labs—Laboratory for Accelerator Based Science are gratefully acknowledged. Jean Cleymans Chair of the Local Organizing Committee Local Organizing Committee Oana Boeriu Jean Cleymans Simon H Connell Alan S Cornell William A Horowitz Andre Peshier Trevor Vickey Zeblon Z Vilakazi Group picture

Talking the Higgs Boson with Dr. Joseph Incandela: Third Lecture in the DOE Science Speaker Series (includes opening remarks from Dr. Bill Brinkman and introduction by Energy Secretary, Dr. Steven Chu)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Incandela, Joseph

In July of 2012, scientists leading two different research teams, working independently of each other, announced that they had almost certain proof of the long-sought Higgs boson. Though Cern did not call the discovery "official", many physicists conceded the evidence was now so compelling they had surely found the missing particle. The formal confirmation will come over the next few months of further investigation. The experiments are taking place at the Large Hadron Collider (LHC), and this third lecture in the DOE Science Speaker Series is given by one of those announcing scientists in July. He is Dr. Joseph Incandela,more » the current spokesperson for the Compact Muon Solenoid (CMS) Experiment at CERN. He was heavily involved in the search for the top quark at Fermi and is from the University of California, Santa Barbara. The title he gives his presentation is "Searching for the genetic code of our universe: Discovery at the LHC."« less

One Year of FOS Measurements in CMS Experiment at CERN

NASA Astrophysics Data System (ADS)

Szillási, Zoltán; Buontempo, Salvatore; Béni, Noémi; Breglio, Giovanni; Cusano, Andrea; Laudati, Armando; Giordano, Michele; Saccomanno, Andrea; Druzhkin, Dmitry; Tsirou, Andromachi

Results are presented on the activity carried out by our research group, in collaboration with the SME Optosmart s.r.l. (an Italian spin-off company), on the application of Fiber Optic Sensor (FOS) techniques to monitor high-energy physics (HEP) detectors. Assuming that Fiber Bragg Grating sensors (FBGs) radiation hardness has been deeply studied for other field of application, we have applied the FBG technology to the HEP research domain. We present here the experimental evidences of the solid possibility to use such a class of sensors also in HEP detector very complex environmental side conditions. In particular we present more than one year data results of FBG measurements in the Compact Muon Solenoid (CMS) experiment set up at the CERN, where we have monitored temperatures (within CMS core) and strains in different locations by using FBG sensors during the detector operation with the Large Hadron Collider (LHC) collisions and high magnetic field. FOS data and FOS readout system stability and reliability is demonstrated, with continuous 24/24 h 7/7d data taking under severe and complex side conditions.

Final Report for U.S. DOE GRANT No. DEFG02-96ER41015 November 1, 2010 - April 30, 2013 entitled HIGH ENERGY ACCELERATOR AND COLLIDING BEAM USER GROUP at the UNIVERSITY of MARYLAND

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hadley, Nicholas; Jawahery, Abolhassan; Eno, Sarah C

2013-07-26

We have finished the third year of a three year grant cycle with the U.S. Department of Energy for which we were given a five month extension (U.S. D.O.E. Grant No. DEFG02-96ER41015). This document is the fi nal report for this grant and covers the period from November 1, 2010 to April 30, 2013. The Maryland program is administered as a single task with Professor Nicholas Hadley as Principal Investigator. The Maryland experimental HEP group is focused on two major research areas. We are members of the CMS experiment at the LHC at CERN working on the physics of themore » Energy Frontier. We are also analyzing the data from the Babar experiment at SLAC while doing design work and R&D towards a Super B experiment as part of the Intensity Frontier. We have recently joined the LHCb experiment at CERN. We concluded our activities on the D experiment at Fermilab in 2009.« less

Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN.

PubMed

Toivanen, V; Bellodi, G; Dimov, V; Küchler, D; Lombardi, A M; Maintrot, M

2016-02-01

Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT) section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented.

Testing the scalar sector of the twin Higgs model at colliders

DOE PAGES

Chacko, Zackaria; Kilic, Can; Najjari, Saereh; ...

2018-03-22

We consider Mirror Twin Higgs models in which the breaking of the global symmetry is realized linearly. In this scenario, the radial mode in the Higgs potential is present in the spectrum, and constitutes a second portal between the twin and SM sectors. We show that a study of the properties of this particle at colliders, when combined with precision measurements of the light Higgs, can be used to overdetermine the form of the scalar potential, thereby confirming that it possesses an enhanced global symmetry as dictated by the Twin Higgs mechanism. We find that, although the reach of themore » LHC for this state is limited, future linear colliders will be able to explore a significant part of the preferred parameter space, allowing the possibility of directly testing the Twin Higgs framework.« less

Testing the scalar sector of the twin Higgs model at colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chacko, Zackaria; Kilic, Can; Najjari, Saereh

We consider Mirror Twin Higgs models in which the breaking of the global symmetry is realized linearly. In this scenario, the radial mode in the Higgs potential is present in the spectrum, and constitutes a second portal between the twin and SM sectors. We show that a study of the properties of this particle at colliders, when combined with precision measurements of the light Higgs, can be used to overdetermine the form of the scalar potential, thereby confirming that it possesses an enhanced global symmetry as dictated by the Twin Higgs mechanism. We find that, although the reach of themore » LHC for this state is limited, future linear colliders will be able to explore a significant part of the preferred parameter space, allowing the possibility of directly testing the Twin Higgs framework.« less

CCD developments for particle colliders

NASA Astrophysics Data System (ADS)

Stefanov, Konstantin D.

2006-09-01

Charge Coupled Devices (CCDs) have been successfully used in several high-energy physics experiments over the last 20 years. Their small pixel size and excellent precision provide superb tool for studying of short-lived particles and understanding the nature at fundamental level. Over the last years the Linear Collider Flavour Identification (LCFI) collaboration has developed Column-Parallel CCDs (CPCCD) and CMOS readout chips to be used for the vertex detector at the International Linear Collider (ILC). The CPCCDs are very fast devices capable of satisfying the challenging requirements imposed by the beam structure of the superconducting accelerator. First set of prototype devices have been designed, manufactured and successfully tested, with second-generation chips on the way. Another idea for CCD-based device, the In-situ Storage Image Sensor (ISIS) is also under development and the first prototype is in production.

Singlet-catalyzed electroweak phase transitions and precision Higgs boson studies

NASA Astrophysics Data System (ADS)

Profumo, Stefano; Ramsey-Musolf, Michael J.; Wainwright, Carroll L.; Winslow, Peter

2015-02-01

We update the phenomenology of gauge-singlet extensions of the Standard Model scalar sector and their implications for the electroweak phase transition. Considering the introduction of one real scalar singlet to the scalar potential, we analyze present constraints on the potential parameters from Higgs coupling measurements at the Large Hadron Collider (LHC) and electroweak precision observables for the kinematic regime in which no new scalar decay modes arise. We then show how future precision measurements of Higgs boson signal strengths and the Higgs self-coupling could probe the scalar potential parameter space associated with a strong first-order electroweak phase transition. We illustrate using benchmark precision for several future collider options, including the high-luminosity LHC, the International Linear Collider, Triple-Large Electron-Positron collider, the China Electron-Positron Collider, and a 100 TeV proton-proton collider, such as the Very High Energy LHC or the Super Proton-Proton Collider. For the regions of parameter space leading to a strong first-order electroweak phase transition, we find that there exists considerable potential for observable deviations from purely Standard Model Higgs properties at these prospective future colliders.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Andre, J.M.; et al.

The data acquisition system (DAQ) of the CMS experiment at the CERN Large Hadron Collider assembles events at a rate of 100 kHz, transporting event data at an aggregate throughput of to the high-level trigger farm. The DAQ architecture is based on state-of-the-art network technologies for the event building. For the data concentration, 10/40 Gbit/s Ethernet technologies are used together with a reduced TCP/IP protocol implemented in FPGA for a reliable transport between custom electronics and commercial computing hardware. A 56 Gbit/s Infiniband FDR Clos network has been chosen for the event builder. This paper presents the implementation and performancemore » of the event-building system.« less

Planck 2010: From the Planck Scale to the ElectroWeak Scale (Part 9)

ScienceCinema

None

2018-06-27

"Planck 2010: From the Planck Scale to the ElectroWeak Scale". The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC. The main topic covered will be "Supersymmetry", with discussions on: supergravity and string phenomenology, extra dimensions, electroweak symmetry breaking, LHC and Tevatron physics, collider physics, flavor and neutrino physics, astroparticle and cosmology, gravity and holography, and strongly coupled physics and CFT.

Evolution of user analysis on the grid in ATLAS

NASA Astrophysics Data System (ADS)

Dewhurst, A.; Legger, F.; ATLAS Collaboration

2017-10-01

More than one thousand physicists analyse data collected by the ATLAS experiment at the Large Hadron Collider (LHC) at CERN through 150 computing facilities around the world. Efficient distributed analysis requires optimal resource usage and the interplay of several factors: robust grid and software infrastructures, and system capability to adapt to different workloads. The continuous automatic validation of grid sites and the user support provided by a dedicated team of expert shifters have been proven to provide a solid distributed analysis system for ATLAS users. Typical user workflows on the grid, and their associated metrics, are discussed. Measurements of user job performance and typical requirements are also shown.

ATLAS computing on Swiss Cloud SWITCHengines

NASA Astrophysics Data System (ADS)

Haug, S.; Sciacca, F. G.; ATLAS Collaboration

2017-10-01

Consolidation towards more computing at flat budgets beyond what pure chip technology can offer, is a requirement for the full scientific exploitation of the future data from the Large Hadron Collider at CERN in Geneva. One consolidation measure is to exploit cloud infrastructures whenever they are financially competitive. We report on the technical solutions and the performances used and achieved running simulation tasks for the ATLAS experiment on SWITCHengines. SWITCHengines is a new infrastructure as a service offered to Swiss academia by the National Research and Education Network SWITCH. While solutions and performances are general, financial considerations and policies, on which we also report, are country specific.

Incoherent vector mesons production in PbPb ultraperipheral collisions at the LHC

NASA Astrophysics Data System (ADS)

Xie, Ya-Ping; Chen, Xurong

2017-03-01

The incoherent rapidity distributions of vector mesons are computed in dipole model in PbPb ultraperipheral collisions at the CERN Large Hadron Collider (LHC). The IIM model fitted from newer data is employed in the dipole amplitude. The Boosted Gaussian and Gaus-LC wave functions for vector mesons are implemented in the calculations as well. Predictions for the J / ψ, ψ (2 s), ρ and ϕ incoherent rapidity distributions are evaluated and compared with experimental data and other theoretical predictions in this paper. We obtain closer predictions of the incoherent rapidity distributions for J / ψ than previous calculations in the IIM model.

Planck 2010: From the Planck Scale to the ElectroWeak Scale (Part 5)

ScienceCinema

None

2018-06-27

"Planck 2010: From the Planck Scale to the ElectroWeak Scale". The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC. The main topic covered will be "Supersymmetry", with discussions on: supergravity and string phenomenology, extra dimensions, electroweak symmetry breaking, LHC and Tevatron physics, collider physics, flavor and neutrino physics, astroparticle and cosmology, gravity and holography, and strongly coupled physics and CFT.

Planck 2010: From the Planck Scale to the ElectroWeak Scale (Part 6)

ScienceCinema

None

2018-06-28

"Planck 2010: From the Planck Scale to the ElectroWeak Scale". The conference will be the twelfth one in a series of meetings on physics beyond the Standard Model, organized jointly by several European groups: Bonn, CERN, Ecole Polytechnique, ICTP, Madrid, Oxford, Padua, Pisa, SISSA and Warsaw as part of activities in the framework of the European network UNILHC. The main topic covered will be "Supersymmetry", with discussions on: supergravity and string phenomenology, extra dimensions, electroweak symmetry breaking, LHC and Tevatron physics, collider physics, flavor and neutrino physics, astroparticle and cosmology, gravity and holography, and strongly coupled physics and CFT.

The MoEDAL Experiment at the Lhc — a New Light on the High Energy Frontier

NASA Astrophysics Data System (ADS)

Pinfold, James L.

2014-01-01

In 2010, the CERN (European Centre for Particle Physics Research) Research Board unanimously approved MoEDAL, the seventh international experiment at the Large Hadron Collider (LHC), which is designed to search for avatars of new physics signified by highly ionizing particles. A MoEDAL discovery would have revolutionary implications for our understanding of the microcosm, providing insights into such fundamental questions as: do magnetic monopoles exist, are there extra dimensions or new symmetries of nature; what is the mechanism for the generation of mass; what is the nature of dark matter and how did the big bang unfurl at the earliest times.

The MoEDAL Experiment at the Lhc -- a New Light on the High Energy Frontier

NASA Astrophysics Data System (ADS)

Pinfold, James L.

2014-04-01

In 2010, the CERN (European Centre for Particle Physics Research) Research Board unanimously approved MoEDAL, the seventh international experiment at the Large Hadron Collider (LHC), which is designed to search for avatars of new physics signified by highly ionizing particles. A MoEDAL discovery would have revolutionary implications for our understanding of the microcosm, providing insights into such fundamental questions as: do magnetic monopoles exist, are there extra dimensions or new symmetries of nature; what is the mechanism for the generation of mass; what is the nature of dark matter and how did the big bang unfurl at the earliest times.

Production and integration of the ATLAS Insertable B-Layer

NASA Astrophysics Data System (ADS)

Abbott, B.; Albert, J.; Alberti, F.; Alex, M.; Alimonti, G.; Alkire, S.; Allport, P.; Altenheiner, S.; Ancu, L. S.; Anderssen, E.; Andreani, A.; Andreazza, A.; Axen, B.; Arguin, J.; Backhaus, M.; Balbi, G.; Ballansat, J.; Barbero, M.; Barbier, G.; Bassalat, A.; Bates, R.; Baudin, P.; Battaglia, M.; Beau, T.; Beccherle, R.; Bell, A.; Benoit, M.; Bermgan, A.; Bertsche, C.; Bertsche, D.; Bilbao de Mendizabal, J.; Bindi, F.; Bomben, M.; Borri, M.; Bortolin, C.; Bousson, N.; Boyd, R. G.; Breugnon, P.; Bruni, G.; Brossamer, J.; Bruschi, M.; Buchholz, P.; Budun, E.; Buttar, C.; Cadoux, F.; Calderini, G.; Caminada, L.; Capeans, M.; Carney, R.; Casse, G.; Catinaccio, A.; Cavalli-Sforza, M.; Červ, M.; Cervelli, A.; Chau, C. C.; Chauveau, J.; Chen, S. P.; Chu, M.; Ciapetti, M.; Cindro, V.; Citterio, M.; Clark, A.; Cobal, M.; Coelli, S.; Collot, J.; Crespo-Lopez, O.; Dalla Betta, G. F.; Daly, C.; D'Amen, G.; Dann, N.; Dao, V.; Darbo, G.; DaVia, C.; David, P.; Debieux, S.; Delebecque, P.; De Lorenzi, F.; de Oliveira, R.; Dette, K.; Dietsche, W.; Di Girolamo, B.; Dinu, N.; Dittus, F.; Diyakov, D.; Djama, F.; Dobos, D.; Dondero, P.; Doonan, K.; Dopke, J.; Dorholt, O.; Dube, S.; Dzahini, D.; Egorov, K.; Ehrmann, O.; Einsweiler, K.; Elles, S.; Elsing, M.; Eraud, L.; Ereditato, A.; Eyring, A.; Falchieri, D.; Falou, A.; Fausten, C.; Favareto, A.; Favre, Y.; Feigl, S.; Fernandez Perez, S.; Ferrere, D.; Fleury, J.; Flick, T.; Forshaw, D.; Fougeron, D.; Franconi, L.; Gabrielli, A.; Gaglione, R.; Gallrapp, C.; Gan, K. K.; Garcia-Sciveres, M.; Gariano, G.; Gastaldi, T.; Gavrilenko, I.; Gaudiello, A.; Geffroy, N.; Gemme, C.; Gensolen, F.; George, M.; Ghislain, P.; Giangiacomi, N.; Gibson, S.; Giordani, M. P.; Giugni, D.; Gjersdal, H.; Glitza, K. W.; Gnani, D.; Godlewski, J.; Gonella, L.; Gonzalez-Sevilla, S.; Gorelov, I.; Gorišek, A.; Gössling, C.; Grancagnolo, S.; Gray, H.; Gregor, I.; Grenier, P.; Grinstein, S.; Gris, A.; Gromov, V.; Grondin, D.; Grosse-Knetter, J.; Guescini, F.; Guido, E.; Gutierrez, P.; Hallewell, G.; Hartman, N.; Hauck, S.; Hasi, J.; Hasib, A.; Hegner, F.; Heidbrink, S.; Heim, T.; Heinemann, B.; Hemperek, T.; Hessey, N. P.; Hetmánek, M.; Hinman, R. R.; Hoeferkamp, M.; Holmes, T.; Hostachy, J.; Hsu, S. C.; Hügging, F.; Husi, C.; Iacobucci, G.; Ibragimov, I.; Idarraga, J.; Ikegami, Y.; Ince, T.; Ishmukhametov, R.; Izen, J. M.; Janoška, Z.; Janssen, J.; Jansen, L.; Jeanty, L.; Jensen, F.; Jentzsch, J.; Jezequel, S.; Joseph, J.; Kagan, H.; Kagan, M.; Karagounis, M.; Kass, R.; Kastanas, A.; Kenney, C.; Kersten, S.; Kind, P.; Klein, M.; Klingenberg, R.; Kluit, R.; Kocian, M.; Koffeman, E.; Korchak, O.; Korolkov, I.; Kostyukhina-Visoven, I.; Kovalenko, S.; Kretz, M.; Krieger, N.; Krüger, H.; Kruth, A.; Kugel, A.; Kuykendall, W.; La Rosa, A.; Lai, C.; Lantzsch, K.; Lapoire, C.; Laporte, D.; Lari, T.; Latorre, S.; Leyton, M.; Lindquist, B.; Looper, K.; Lopez, I.; Lounis, A.; Lu, Y.; Lubatti, H. J.; Maeland, S.; Maier, A.; Mallik, U.; Manca, F.; Mandelli, B.; Mandić, I.; Marchand, D.; Marchiori, G.; Marx, M.; Massol, N.; Mättig, P.; Mayer, J.; McGoldrick, G.; Mekkaoui, A.; Menouni, M.; Menu, J.; Meroni, C.; Mesa, J.; Michal, S.; Miglioranzi, S.; Mikuž, M.; Miucci, A.; Mochizuki, K.; Monti, M.; Moore, J.; Morettini, P.; Morley, A.; Moss, J.; Muenstermann, D.; Murray, P.; Nakamura, K.; Nellist, C.; Nelson, D.; Nessi, M.; Nisius, R.; Nordberg, M.; Nuiry, F.; Obermann, T.; Ockenfels, W.; Oide, H.; Oriunno, M.; Ould-Saada, F.; Padilla, C.; Pangaud, P.; Parker, S.; Pelleriti, G.; Pernegger, H.; Piacquadio, G.; Picazio, A.; Pohl, D.; Polini, A.; Pons, X.; Popule, J.; Portell Bueso, X.; Potamianos, K.; Povoli, M.; Puldon, D.; Pylypchenko, Y.; Quadt, A.; Quayle, B.; Rarbi, F.; Ragusa, F.; Rambure, T.; Richards, E.; Riegel, C.; Ristic, B.; Rivière, F.; Rizatdinova, F.; RØhne, O.; Rossi, C.; Rossi, L. P.; Rovani, A.; Rozanov, A.; Rubinskiy, I.; Rudolph, M. S.; Rummler, A.; Ruscino, E.; Sabatini, F.; Salek, D.; Salzburger, A.; Sandaker, H.; Sannino, M.; Sanny, B.; Scanlon, T.; Schipper, J.; Schmidt, U.; Schneider, B.; Schorlemmer, A.; Schroer, N.; Schwemling, P.; Sciuccati, A.; Seidel, S.; Seiden, A.; Šícho, P.; Skubic, P.; Sloboda, M.; Smith, D. S.; Smith, M.; Sood, A.; Spencer, E.; Stramaglia, M.; Strauss, M.; Stucci, S.; Stugu, B.; Stupak, J.; Styles, N.; Su, D.; Takubo, Y.; Tassan, J.; Teng, P.; Teixeira, A.; Terzo, S.; Therry, X.; Todorov, T.; Tomášek, M.; Toms, K.; Travaglini, R.; Trischuk, W.; Troncon, C.; Troska, G.; Tsiskaridze, S.; Tsurin, I.; Tsybychev, D.; Unno, Y.; Vacavant, L.; Verlaat, B.; Vigeolas, E.; Vogt, M.; Vrba, V.; Vuillermet, R.; Wagner, W.; Walkowiak, W.; Wang, R.; Watts, S.; Weber, M. S.; Weber, M.; Weingarten, J.; Welch, S.; Wenig, S.; Wensing, M.; Wermes, N.; Wittig, T.; Wittgen, M.; Yildizkaya, T.; Yang, Y.; Yao, W.; Yi, Y.; Zaman, A.; Zaidan, R.; Zeitnitz, C.; Ziolkowski, M.; Zivkovic, V.; Zoccoli, A.; Zwalinski, L.

2018-05-01

During the shutdown of the CERN Large Hadron Collider in 2013-2014, an additional pixel layer was installed between the existing Pixel detector of the ATLAS experiment and a new, smaller radius beam pipe. The motivation for this new pixel layer, the Insertable B-Layer (IBL), was to maintain or improve the robustness and performance of the ATLAS tracking system, given the higher instantaneous and integrated luminosities realised following the shutdown. Because of the extreme radiation and collision rate environment, several new radiation-tolerant sensor and electronic technologies were utilised for this layer. This paper reports on the IBL construction and integration prior to its operation in the ATLAS detector.

Dissecting the Science of "Angels and Demons" or Antimatter and Other Matters (Vernon W. Hughes Memorial Lecture)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gordon, Howard

2009-05-27

Howard Gordon, a physicist from the U.S. Department of Energy’s Brookhaven National Laboratory, and local educators will separate the science facts from the science fiction of “Angels & Demons,” a major motion picture based on Dan Brown’s best-selling novel. The film, which opens nationally in theaters today, focuses on a plot to destroy the Vatican using antimatter stolen from the Large Hadron Collider (LHC) at the European particle physics laboratory CERN. Speakers will explain the real science of the LHC, including antimatter – oppositely charged cousins of ordinary matter with intriguing properties.

Luminosity limits for liquid argon calorimetry

NASA Astrophysics Data System (ADS)

J, Rutherfoord; B, Walker R.

2012-12-01

We have irradiated liquid argon ionization chambers with betas using high-activity Strontium-90 sources. The radiation environment is comparable to that in the liquid argon calorimeters which are part of the ATLAS detector installed at CERN's Large Hadron Collider. We measure the ionization current over a wide range of applied potential for two different source activities and for three different chamber gaps. These studies provide operating experience at exceptionally high ionization rates. We can operate these chambers either in the normal mode or in the space-charge limited regime and thereby determine the transition point between the two. From the transition point we indirectly extract the positive argon ion mobility.

Angels and Demons: The Science Behind the Scenes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Graf, Norman

Does antimatter really exist? How and why do scientists produce and use it? Does CERN exist and is there an underground complex deep beneath the Swiss/French border? Is truth stranger than fiction? Find out at the coming public lecture. On Tuesday, May 12, SLAC physicist Norman Graf will discuss the real science behind Angels & Demons, Dan Brown's blockbuster novel and the basis of an upcoming Tom Hanks movie. Graf's' talk is one in a series of public lectures across the U.S., Canada and Puerto Rico to share the science of antimatter and the Large Hadron Collider, and the excitementmore » of particle physics research.« less

Shadowing effects on J/ψ and Υ production at energies available at the CERN Large Hadron Collider

DOE PAGES

Vogt, R.

2015-09-17

Proton-nucleus collisions have been used as a intermediate baseline for the determination of cold medium effects. They lie between proton-proton collisions in vacuum and nucleus-nucleus collisions which are expected to be dominated by hot matter effects. Modifications of the quark densities in nuclei relative to those of the proton are well established although those of the gluons in the nucleus are not well understood. We focus on the effect of these on quarkonium production in proton-lead collisions at the LHC at a center of mass energy of 5.02 TeV.

Higgs radiation off top quarks at the Tevatron and the LHC.

PubMed

Beenakker, W; Dittmaier, S; Krämer, M; Plümper, B; Spira, M; Zerwas, P M

2001-11-12

Higgs bosons can be searched for in the channels pp macro/pp-->tt macro H + X at the Fermilab Tevatron and the Cern Large Hadron Collider (LHC). We have calculated the QCD corrections to these processes in the standard model at next-to-leading order. The higher-order corrections reduce the renormalization and factorization scale dependence considerably and stabilize the theoretical predictions for the cross sections. At the central scale mu = (2m(t)+M(H))/2 the properly defined K factors are slightly below unity for the Tevatron (K approximately 0.8) and slightly above unity for the LHC (K approximately 1.2).

Exclusive photoproduction of vector mesons in proton-lead ultraperipheral collisions at the LHC

NASA Astrophysics Data System (ADS)

Xie, Ya-Ping; Chen, Xurong

2018-02-01

Rapidity distributions of vector mesons are computed in dipole model proton-lead ultraperipheral collisions (UPCs) at the CERN Larger Hadron Collider (LHC). The dipole model framework is implemented in the calculations of cross sections in the photon-hadron interaction. The bCGC model and Boosted Gaussian wave functions are employed in the scattering amplitude. We obtain predictions of rapidity distributions of J / ψ meson proton-lead ultraperipheral collisions. The predictions give a good description to the experimental data of ALICE. The rapidity distributions of ϕ, ω and ψ (2 s) mesons in proton-lead ultraperipheral collisions are also presented in this paper.

Longitudinal decorrelation measures of flow magnitude and event-plane angles in ultrarelativistic nuclear collisions

NASA Astrophysics Data System (ADS)

BoŻek, Piotr; Broniowski, Wojciech

2018-03-01

We discuss the forward-backward correlations of harmonic flow in Pb +Pb collisions at the CERN Large Hadron Collider, applying standard multibin measures as well as new measures proposed here. We illustrate the methods with hydrodynamic model simulations based on event-by-event initial conditions from the wounded quark model with asymmetric rapidity emission profiles. Within the model, we examine independently the event-plane angle and the flow magnitude decorrelations. We find a specific hierarchy between various flow decorrelation measures and confirm certain factorization relations. We find qualitative agreement of the model and the data from the ATLAS and CMS Collaborations.

Compendium of Instrumentation Whitepapers on Frontier Physics Needs for Snowmass 2013

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lipton, R.

2013-01-01

Contents of collection of whitepapers include: Operation of Collider Experiments at High Luminosity; Level 1 Track Triggers at HL-LHC; Tracking and Vertex Detectors for a Muon Collider; Triggers for hadron colliders at the energy frontier; ATLAS Upgrade Instrumentation; Instrumentation for the Energy Frontier; Particle Flow Calorimetry for CMS; Noble Liquid Calorimeters; Hadronic dual-readout calorimetry for high energy colliders; Another Detector for the International Linear Collider; e+e- Linear Colliders Detector Requirements and Limitations; Electromagnetic Calorimetry in Project X Experiments The Project X Physics Study; Intensity Frontier Instrumentation; Project X Physics Study Calorimetry Report; Project X Physics Study Tracking Report; The LHCbmore » Upgrade; Neutrino Detectors Working Group Summary; Advanced Water Cherenkov R&D for WATCHMAN; Liquid Argon Time Projection Chamber (LArTPC); Liquid Scintillator Instrumentation for Physics Frontiers; A readout architecture for 100,000 pixel Microwave Kinetic In- ductance Detector array; Instrumentation for New Measurements of the Cosmic Microwave Background polarization; Future Atmospheric and Water Cherenkov ?-ray Detectors; Dark Energy; Can Columnar Recombination Provide Directional Sensitivity in WIMP Search?; Instrumentation Needs for Detection of Ultra-high Energy Neu- trinos; Low Background Materials for Direct Detection of Dark Matter; Physics Motivation for WIMP Dark Matter Directional Detection; Solid Xenon R&D at Fermilab; Ultra High Energy Neutrinos; Instrumentation Frontier: Direct Detection of WIMPs; nEXO detector R&D; Large Arrays of Air Cherenkov Detectors; and Applications of Laser Interferometry in Fundamental Physics Experiments.« less

Beam dynamic simulations of the CLIC crab cavity and implications on the BDS

NASA Astrophysics Data System (ADS)

Shinton, I. R. R.; Burt, G.; Glasman, C. J.; Jones, R. M.; Wolski, A.

2011-11-01

The Compact Linear Collider (CLIC) is a proposed electron positron linear collider design aiming to achieve a centre of mass energy of up to 3 TeV. The main accelerating structures in CLIC operate at an X-band frequency of 11.994 GHz with an accelerating gradient of 100 MV/m. The present design requires the beams to collide at a small crossing angle of 10 mrad per line giving a resultant overall crossing angle of 20 mrad. Transverse deflecting cavities, referred to as "Crab cavities", are installed in the beam delivery system (BDS) of linear collider designs in order to ensure the final luminosity at the interaction point (IP) is comparable to that in a head on collision. We utilise the beam tracking code PLACET combined with the beam-beam code GUINEA-PIG to calculate the resulting luminosity at the IP. We follow a similar tuning procedure to that used for the design of the ILC crab cavities and anitcrab cavities. However an unexpected loss in luminosity of 10% was observed for the 20 mrad design was observed. It was discovered that the action of the crab cavities can affect the geometric aberrations resulting from the sextupoles used to correct chromatic effects in the beam delivery system. This has direct consequences regarding the design of the present CLIC BDS.

The International Linear Collider Technical Design Report - Volume 2: Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Baer, Howard; Barklow, Tim; Fujii, Keisuke

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carriedmore » out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.« less

The International Linear Collider Technical Design Report - Volume 4: Detectors

DOE Office of Scientific and Technical Information (OSTI.GOV)

Behnke, Ties

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carriedmore » out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.« less

USLCSG Task Force

Science.gov Websites

Unites States Linear Collider Steering Group dot dot dot dot What's New! June 2003 Meeting Welcome to the USLCSG Task Force at the Stanford Linear Accelerator Center [Enter] dot dot SLAC Page Owners

Applications of electron lenses: scraping of high-power beams, beam-beam compensation, and nonlinear optics

DOE Office of Scientific and Technical Information (OSTI.GOV)

Stancari, Giulio

Electron lenses are pulsed, magnetically confined electron beams whose current-density profile is shaped to obtain the desired effect on the circulating beam. Electron lenses were used in the Fermilab Tevatron collider for bunch-by-bunch compensation of long-range beam-beam tune shifts, for removal of uncaptured particles in the abort gap, for preliminary experiments on head-on beam-beam compensation, and for the demonstration of halo scraping with hollow electron beams. Electron lenses for beam-beam compensation are being commissioned in the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL). Hollow electron beam collimation and halo control were studied as an option to complementmore » the collimation system for the upgrades of the Large Hadron Collider (LHC) at CERN; a conceptual design was recently completed. Because of their electric charge and the absence of materials close to the proton beam, electron lenses may also provide an alternative to wires for long-range beam-beam compensation in LHC luminosity upgrade scenarios with small crossing angles. At Fermilab, we are planning to install an electron lens in the Integrable Optics Test Accelerator (IOTA, a 40-m ring for 150-MeV electrons) as one of the proof-of-principle implementations of nonlinear integrable optics to achieve large tune spreads and more stable beams without loss of dynamic aperture.« less

Extracting muon momentum scale corrections for hadron collider experiments

NASA Astrophysics Data System (ADS)

Bodek, A.; van Dyne, A.; Han, J. Y.; Sakumoto, W.; Strelnikov, A.

2012-10-01

We present a simple method for the extraction of corrections for bias in the measurement of the momentum of muons in hadron collider experiments. Such bias can originate from a variety of sources such as detector misalignment, software reconstruction bias, and uncertainties in the magnetic field. The two step method uses the mean <1/p^{μ}T rangle for muons from Z→ μμ decays to determine the momentum scale corrections in bins of charge, η and ϕ. In the second step, the corrections are tuned by using the average invariant mass < MZ_{μμ }rangle of Z→ μμ events in the same bins of charge η and ϕ. The forward-backward asymmetry of Z/ γ ∗→ μμ pairs as a function of μ + μ - mass, and the ϕ distribution of Z bosons in the Collins-Soper frame are used to ascertain that the corrections remove the bias in the momentum measurements for positive versus negatively charged muons. By taking the sum and difference of the momentum scale corrections for positive and negative muons, we isolate additive corrections to 1/p^{μ}T that may originate from misalignments and multiplicative corrections that may originate from mis-modeling of the magnetic field (∫ Bṡ d L). This method has recently been used in the CDF experiment at Fermilab and in the CMS experiment at the Large Hadron Collider at CERN.

Potential and challenges of the physics measurements with very forward detectors at linear colliders

NASA Astrophysics Data System (ADS)

Božović Jelisavčić, Ivanka; Kačarević, G.; Lukić, S.; Poss, S.; Sailer, A.; Smiljanić, I.; FCAL Collaboration

2016-04-01

The instrumentation of the very forward region of a detector at a future linear collider (ILC, CLIC) is briefly reviewed. The status of the FCAL R&D activity is given with emphasis on physics and technological challenges. The current status of studies on absolute luminosity measurement, luminosity spectrum reconstruction and high-energy electron identification with the forward calorimeters is given. The impact of FCAL measurements on physics studies is illustrated with an example of the σHWW ṡBR (H →μ+μ-) measurement at 1.4 TeV CLIC.

Calorimetry at the International Linear Collider

NASA Astrophysics Data System (ADS)

Repond, José

2007-03-01

The physics potential of the International Linear Collider depends critically on the jet energy resolution of its detector. Detector concepts are being developed which optimize the jet energy resolution, with the aim of achieving σjet=30%/√{Ejet}. Under the assumption that Particle Flow Algorithms (PFAs), which combine tracking and calorimeter information to reconstruct the energy of hadronic jets, can provide this unprecedented jet energy resolution, calorimeters with very fine granularity are being developed. After a brief introduction outlining the principles of PFAs, the current status of various calorimeter prototype construction projects and their plans for the next few years will be reviewed.

Infrared weak corrections to strongly interacting gauge boson scattering

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ciafaloni, Paolo; Urbano, Alfredo

2010-04-15

We evaluate the impact of electroweak corrections of infrared origin on strongly interacting longitudinal gauge boson scattering, calculating all-order resummed expressions at the double log level. As a working example, we consider the standard model with a heavy Higgs. At energies typical of forthcoming experiments (LHC, International Linear Collider, Compact Linear Collider), the corrections are in the 10%-40% range, with the relative sign depending on the initial state considered and on whether or not additional gauge boson emission is included. We conclude that the effect of radiative electroweak corrections should be included in the analysis of longitudinal gauge boson scattering.

Baryon anomaly and strong color fields in Pb + Pb collisions at 2.76A TeV at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Topor Pop, V.; Gyulassy, M.; Barrette, J.; Gale, C.

2011-10-01

With the HIJING/B¯B v2.0 heavy ion event generator, we explore the phenomenological consequences of several high parton density dynamical effects predicted in central Pb+Pb collisions at the Large Hadron Collider (LHC) energies. These include (1) jet quenching due to parton energy loss (dE/dx), (2) strangeness and hyperon enhancement due to strong longitudinal color field (SCF), and (3) enhancement of baryon-to-meson ratios due to baryon-antibaryon junction (J¯J) loops and SCF effects. The saturation/minijet cutoff scale p0(s,A) and effective string tension κ(s,A) are constrained by our previous analysis of LHC p+p data and recent data on the charged multiplicity for Pb+Pb collisions reported by the ALICE collaboration. We predict the hadron flavor dependence (mesons and baryons) of the nuclear modification factor RAA(pT) and emphasize the possibility that the baryon anomaly could persist at the LHC up to pT˜10 GeV, well beyond the range observed in central Au+Au collisions at RHIC energies.

Colliders as a simultaneous probe of supersymmetric dark matter and Terascale cosmology

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barenboim, Gabriela; /Valencia U.; Lykken, Joseph D.

2006-08-01

Terascale supersymmetry has the potential to provide a natural explanation of the dominant dark matter component of the standard {Lambda}CDM cosmology. However once we impose the constraints on minimal supersymmetry parameters from current particle physics data, a satisfactory dark matter abundance is no longer prima facie natural. This Neutralino Tuning Problem could be a hint of nonstandard cosmology during and/or after the Terascale era. To quantify this possibility, we introduce an alternative cosmological benchmark based upon a simple model of quintessential inflation. This benchmark has no free parameters, so for a given supersymmetry model it allows an unambiguous prediction ofmore » the dark matter relic density. As a example, we scan over the parameter space of the CMSSM, comparing the neutralino relic density predictions with the bounds from WMAP. We find that the WMAP-allowed regions of the CMSSM are an order of magnitude larger if we use the alternative cosmological benchmark, as opposed to {Lambda}CDM. Initial results from the CERN Large Hadron Collider will distinguish between the two allowed regions.« less

Event-by-event gluon multiplicity, energy density, and eccentricities in ultrarelativistic heavy-ion collisions

NASA Astrophysics Data System (ADS)

Schenke, Björn; Tribedy, Prithwish; Venugopalan, Raju

2012-09-01

The event-by-event multiplicity distribution, the energy densities and energy density weighted eccentricity moments ɛn (up to n=6) at early times in heavy-ion collisions at both the BNL Relativistic Heavy Ion Collider (RHIC) (s=200GeV) and the CERN Large Hardron Collider (LHC) (s=2.76TeV) are computed in the IP-Glasma model. This framework combines the impact parameter dependent saturation model (IP-Sat) for nucleon parton distributions (constrained by HERA deeply inelastic scattering data) with an event-by-event classical Yang-Mills description of early-time gluon fields in heavy-ion collisions. The model produces multiplicity distributions that are convolutions of negative binomial distributions without further assumptions or parameters. In the limit of large dense systems, the n-particle gluon distribution predicted by the Glasma-flux tube model is demonstrated to be nonperturbatively robust. In the general case, the effect of additional geometrical fluctuations is quantified. The eccentricity moments are compared to the MC-KLN model; a noteworthy feature is that fluctuation dominated odd moments are consistently larger than in the MC-KLN model.

Beam energy dependence of pseudorapidity distributions of charged particles produced in relativistic heavy-ion collisions

NASA Astrophysics Data System (ADS)

Basu, Sumit; Nayak, Tapan K.; Datta, Kaustuv

2016-06-01

Heavy-ion collisions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the Large Hadron Collider at CERN probe matter at extreme conditions of temperature and energy density. Most of the global properties of the collisions can be extracted from the measurements of charged-particle multiplicity and pseudorapidity (η ) distributions. We have shown that the available experimental data on beam energy and centrality dependence of η distributions in heavy-ion (Au +Au or Pb +Pb ) collisions from √{sNN}=7.7 GeV to 2.76 TeV are reasonably well described by the AMPT model, which is used for further exploration. The nature of the η distributions has been described by a double Gaussian function using a set of fit parameters, which exhibit a regular pattern as a function of beam energy. By extrapolating the parameters to a higher energy of √{sNN}=5.02 TeV, we have obtained the charged-particle multiplicity densities, η distributions, and energy densities for various centralities. Incidentally, these results match well with some of the recently published data by the ALICE Collaboration.

Test beam studies of silicon timing for use in calorimetry

DOE PAGES

Apresyan, A.; Bolla, G.; Bornheim, A.; ...

2016-04-12

The high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN is expected to provide instantaneous luminosities of 5 X 10 34 cm –2 s –1. The high luminosities expected at the HL-LHC will be accompanied by a factor of 5 to 10 more pileup compared with LHC conditions in 2015, causing general confusion for particle identification and event reconstruction. Precision timing allows to extend calorimetric measurements into such a high density environment by subtracting the energy deposits from pileup interactions. Calorimeters employing silicon as the active component have recently become a popular choice for the HL-LHC and futuremore » collider experiments which face very high radiation environments. In this article, we present studies of basic calorimetric and precision timing measurements using a prototype composed of tungsten absorber and silicon sensor as the active medium. Lastly, we show that for the bulk of electromagnetic showers induced by electrons in the range of 20 GeV to 30 GeV, we can achieve time resolutions better than 25 ps per single pad sensor.« less

In-medium Υ suppression and feed-down in UU and PbPb collisions

NASA Astrophysics Data System (ADS)

Hoelck, J.; Nendzig, F.; Wolschin, G.

2017-02-01

The suppression of Υ mesons in the hot quark-gluon plasma (QGP) versus reduced feed-down is investigated in UU collisions at energies currently available at the BNL Relativistic Heavy Ion Collider and PbPb collisions at energies available at the CERN Large Hadron Collider. Our centrality- and pT-dependent model encompasses screening, collisional damping, and gluodissociation in the QGP. For Υ (1 S ) it is in agreement with data from both STAR and CMS collaborations provided the relativistic Doppler effect and the reduced feed-down from the Υ (n S ) and χb(n P ) states are properly considered. At both energies, most of the Υ (1 S ) suppression is found to be due to reduced feed-down, whereas most of the Υ (2 S ) suppression is caused by hot-medium effects. The importance of the latter increases with energy. The pT dependence is flat due to the relativistic Doppler effect and reduced feed-down. We predict the Υ (1 S ) suppression in PbPb at √{sN N}=5.02 T e V .

Freeze-out conditions in proton-proton collisions at the highest energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Das, Sabita; Mishra, Debadeepti; Chatterjee, Sandeep; Mohanty, Bedangadas

2017-01-01

The freeze-out conditions in proton-proton collisions at √{sNN}=200 , 900, and 7000 GeV have been extracted by fits to the mean hadron yields at midrapidity within the framework of the statistical model of an ideal gas of hadrons and resonances in the grand canonical ensemble. The variation of the extracted freeze-out thermal parameters and the goodness of the fits with √{sN N} are discussed. We find the extracted temperature and baryon chemical potential of the freeze-out surface to be similar in p +p and heavy-ion collisions. On the other hand, the thermal behavior of the strange hadrons is qualitatively different in p +p as compared to A +A collisions. We find an additional parameter accounting for nonequilibrium strangeness production is essential for describing the p +p data. This is in contrast to A +A where the nonequilibrium framework could be successfully replaced by a sequential and complete equilibrium model with an early freeze-out of the strange hadrons.

Orthos, an alarm system for the ALICE DAQ operations

NASA Astrophysics Data System (ADS)

Chapeland, Sylvain; Carena, Franco; Carena, Wisla; Chibante Barroso, Vasco; Costa, Filippo; Denes, Ervin; Divia, Roberto; Fuchs, Ulrich; Grigore, Alexandru; Simonetti, Giuseppe; Soos, Csaba; Telesca, Adriana; Vande Vyvre, Pierre; von Haller, Barthelemy

2012-12-01

ALICE (A Large Ion Collider Experiment) is the heavy-ion detector studying the physics of strongly interacting matter and the quark-gluon plasma at the CERN LHC (Large Hadron Collider). The DAQ (Data Acquisition System) facilities handle the data flow from the detectors electronics up to the mass storage. The DAQ system is based on a large farm of commodity hardware consisting of more than 600 devices (Linux PCs, storage, network switches), and controls hundreds of distributed hardware and software components interacting together. This paper presents Orthos, the alarm system used to detect, log, report, and follow-up abnormal situations on the DAQ machines at the experimental area. The main objective of this package is to integrate alarm detection and notification mechanisms with a full-featured issues tracker, in order to prioritize, assign, and fix system failures optimally. This tool relies on a database repository with a logic engine, SQL interfaces to inject or query metrics, and dynamic web pages for user interaction. We describe the system architecture, the technologies used for the implementation, and the integration with existing monitoring tools.

Colliders as a simultaneous probe of supersymmetric dark matter and Terascale cosmology

NASA Astrophysics Data System (ADS)

Barenboim, Gabriela; Lykken, Joseph D.

2006-12-01

Terascale supersymmetry has the potential to provide a natural explanation of the dominant dark matter component of the standard ΛCDM cosmology. However once we impose the constraints on minimal supersymmetry parameters from current particle physics data, a satisfactory dark matter abundance is no longer prima facie natural. This Neutralino Tuning Problem could be a hint of nonstandard cosmology during and/or after the Terascale era. To quantify this possibility, we introduce an alternative cosmological benchmark based upon a simple model of quintessential inflation. This benchmark has no free parameters, so for a given supersymmetry model it allows an unambiguous prediction of the dark matter relic density. As a example, we scan over the parameter space of the CMSSM, comparing the neutralino relic density predictions with the bounds from WMAP. We find that the WMAP allowed regions of the CMSSM are an order of magnitude larger if we use the alternative cosmological benchmark, as opposed to ΛCDM. Initial results from the CERN Large Hadron Collider will distinguish between the two allowed regions.

Track and vertex reconstruction: From classical to adaptive methods

NASA Astrophysics Data System (ADS)

Strandlie, Are; Frühwirth, Rudolf

2010-04-01

This paper reviews classical and adaptive methods of track and vertex reconstruction in particle physics experiments. Adaptive methods have been developed to meet the experimental challenges at high-energy colliders, in particular, the CERN Large Hadron Collider. They can be characterized by the obliteration of the traditional boundaries between pattern recognition and statistical estimation, by the competition between different hypotheses about what constitutes a track or a vertex, and by a high level of flexibility and robustness achieved with a minimum of assumptions about the data. The theoretical background of some of the adaptive methods is described, and it is shown that there is a close connection between the two main branches of adaptive methods: neural networks and deformable templates, on the one hand, and robust stochastic filters with annealing, on the other hand. As both classical and adaptive methods of track and vertex reconstruction presuppose precise knowledge of the positions of the sensitive detector elements, the paper includes an overview of detector alignment methods and a survey of the alignment strategies employed by past and current experiments.

Precision Timing with Silicon Sensors for Use in Calorimetry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bornheim, A.; Ronzhin, A.; Kim, H.

2017-11-27

The high luminosity upgrade of the Large Hadron Collider (HL-LHC) at CERN is expected to provide instantaneous luminosities of 5 × 10 34 cm -2 s -1. The high luminosities expected at the HL-LHC will be accompanied by a factor of 5 to 10 more pileup compared with LHC conditions in 2015, causing general confusion for particle identification and event reconstruction. Precision timing allows to extend calorimetric measurements into such a high density environment by subtracting the energy deposits from pileup interactions. Calorimeters employing silicon as the active component have recently become a popular choice for the HL- LHC andmore » future collider experiments which face very high radiation environments. We present studies of basic calorimetric and precision timing measurements using a prototype composed of tungsten absorber and silicon sensor as the active medium. We show that for the bulk of electromagnetic showers induced by electrons in the range of 20 GeV to 30 GeV, we can achieve time resolutions better than 25 ps per single pad sensor.« less

Frequency and temperature dependence of electrical breakdown at 21, 30, and 39 GHz.

PubMed

Braun, H H; Döbert, S; Wilson, I; Wuensch, W

2003-06-06

A TeV-range e(+)e(-) linear collider has emerged as one of the most promising candidates to extend the high energy frontier of experimental elementary particle physics. A high accelerating gradient for such a collider is desirable to limit its overall length. Accelerating gradient is mainly limited by electrical breakdown, and it has been generally assumed that this limit increases with increasing frequency for normal-conducting accelerating structures. Since the choice of frequency has a profound influence on the design of a linear collider, the frequency dependence of breakdown has been measured using six exactly scaled single-cell cavities at 21, 30, and 39 GHz. The influence of temperature on breakdown behavior was also investigated. The maximum obtainable surface fields were found to be in the range of 300 to 400 MV/m for copper, with no significant dependence on either frequency or temperature.

Frequency and Temperature Dependence of Electrical Breakdown at 21, 30, and 39GHz

NASA Astrophysics Data System (ADS)

Braun, H. H.; Döbert, S.; Wilson, I.; Wuensch, W.

2003-06-01

A TeV-range e+e- linear collider has emerged as one of the most promising candidates to extend the high energy frontier of experimental elementary particle physics. A high accelerating gradient for such a collider is desirable to limit its overall length. Accelerating gradient is mainly limited by electrical breakdown, and it has been generally assumed that this limit increases with increasing frequency for normal-conducting accelerating structures. Since the choice of frequency has a profound influence on the design of a linear collider, the frequency dependence of breakdown has been measured using six exactly scaled single-cell cavities at 21, 30, and 39GHz. The influence of temperature on breakdown behavior was also investigated. The maximum obtainable surface fields were found to be in the range of 300 to 400 MV/m for copper, with no significant dependence on either frequency or temperature.

Precision studies of observables in p p → W → lν _l and pp → γ ,Z → l^+ l^- processes at the LHC

NASA Astrophysics Data System (ADS)

Alioli, S.; Arbuzov, A. B.; Bardin, D. Yu.; Barzè, L.; Bernaciak, C.; Bondarenko, S. G.; Carloni Calame, C. M.; Chiesa, M.; Dittmaier, S.; Ferrera, G.; de Florian, D.; Grazzini, M.; Höche, S.; Huss, A.; Jadach, S.; Kalinovskaya, L. V.; Karlberg, A.; Krauss, F.; Li, Y.; Martinez, H.; Montagna, G.; Mück, A.; Nason, P.; Nicrosini, O.; Petriello, F.; Piccinini, F.; Płaczek, W.; Prestel, S.; Re, E.; Sapronov, A. A.; Schönherr, M.; Schwinn, C.; Vicini, A.; Wackeroth, D.; Was, Z.; Zanderighi, G.

2017-05-01

This report was prepared in the context of the LPCC Electroweak Precision Measurements at the LHC WG (https://lpcc.web.cern.ch/lpcc/index.php?page=electroweak_wg) and summarizes the activity of a subgroup dedicated to the systematic comparison of public Monte Carlo codes, which describe the Drell-Yan processes at hadron colliders, in particular at the CERN Large Hadron Collider (LHC). This work represents an important step towards the definition of an accurate simulation framework necessary for very high-precision measurements of electroweak (EW) observables such as the W boson mass and the weak mixing angle. All the codes considered in this report share at least next-to-leading-order (NLO) accuracy in the prediction of the total cross sections in an expansion either in the strong or in the EW coupling constant. The NLO fixed-order predictions have been scrutinized at the technical level, using exactly the same inputs, setup and perturbative accuracy, in order to quantify the level of agreement of different implementations of the same calculation. A dedicated comparison, again at the technical level, of three codes that reach next-to-next-to-leading-order (NNLO) accuracy in quantum chromodynamics (QCD) for the total cross section has also been performed. These fixed-order results are a well-defined reference that allows a classification of the impact of higher-order sets of radiative corrections. Several examples of higher-order effects due to the strong or the EW interaction are discussed in this common framework. Also the combination of QCD and EW corrections is discussed, together with the ambiguities that affect the final result, due to the choice of a specific combination recipe. All the codes considered in this report have been run by the respective authors, and the results presented here constitute a benchmark that should be always checked/reproduced before any high-precision analysis is conducted based on these codes. In order to simplify these benchmarking procedures, the codes used in this report, together with the relevant input files and running instructions, can be found in a repository at https://twiki.cern.ch/twiki/bin/view/Main/DrellYanComparison.

Simulation and measurements of the response of an air ionisation chamber exposed to a mixed high-energy radiation field.

PubMed

Vincke, Helmut; Forkel-Wirth, Doris; Perrin, Daniel; Theis, Chris

2005-01-01

CERN's radiation protection group operates a network of simple and robust ionisation chambers that are installed inside CERN's accelerator tunnels. These ionisation chambers are used for the remote reading of ambient dose rate equivalents inside the machines during beam-off periods. This Radiation Protection Monitor for dose rates due to Induced Radioactivity ('PMI', trade name: PTW, Type 34031) is a non-confined air ionisation plastic chamber which is operated under atmospheric pressure. Besides its current field of operation it is planned to extend the use of this detector in the Large Hadron Collider to measure radiation under beam operation conditions to obtain an indication of the machine performance. Until now, studies of the PMI detector have been limited to the response to photons. In order to evaluate its response to other radiation components, this chamber type was tested at CERF, the high-energy reference field facility at CERN. Six PMI detectors were installed around a copper target being irradiated by a mixed hadron beam with a momentum of 120 GeV c(-1). Each of the chosen detector positions was defined by a different radiation field, varying in type and energy of the incident particles. For all positions, detailed measurements and FLUKA simulations of the detector response were performed. This paper presents the promising comparison between the measurements and simulations and analyses the influence of the different particle types on the resulting detector response.

Estimating the charm quark diffusion coefficient and thermalization time from D meson spectra at energies available at the BNL Relativistic Heavy Ion Collider and the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Scardina, Francesco; Das, Santosh K.; Minissale, Vincenzo; Plumari, Salvatore; Greco, Vincenzo

2017-10-01

We describe the propagation of charm quarks in the quark-gluon plasma (QGP) by means of a Boltzmann transport approach. Nonperturbative interaction between heavy quarks and light quarks have been taken into account through a quasiparticle approach in which light partons are dressed with thermal masses tuned to lattice quantum chromodynamics (lQCD) thermodynamics. Such a model is able to describe the main feature of the nonperturbative dynamics: the enhancement of the interaction strength near Tc. We show that the resulting charm in-medium evolution is able to correctly predict simultaneously the nuclear suppression factor, RAA, and the elliptic flow, v2, at both Relativistic Heavy Ion Collider and Large Hadron Collider (LHC) energies and at different centralities. The hadronization of charm quarks is described by mean of an hybrid model of fragmentation plus coalescence and plays a key role toward the agreement with experimental data. We also performed calculations within the Langevin approach, which can lead to very similar RAA(pT) as Boltzmann, but the charm drag coefficient as to be reduced by about a 30 % and also generates an elliptic flow v2(pT) is about a 15 % smaller. We finally compare the space diffusion coefficient 2 π T Ds extracted by our phenomenological approach to lattice QCD results, finding a satisfying agreement within the present systematic uncertainties. Our analysis implies a charm thermalization time, in the p →0 limit, of about 4 -6 fm/c , which is smaller than the QGP lifetime at LHC energy.

A Bridge Too Far: The Demise of the Superconducting Super Collider, 1989-1993

NASA Astrophysics Data System (ADS)

Riordan, Michael

2015-04-01

In October 1993 the US Congress terminated the Superconducting Super Collider -- at over 10 billion the largest and costliest basic-science project ever attempted. It was a disastrous loss for the nation's once-dominant high-energy physics community, which has been slowly declining since then. With the 2012 discovery of the Higgs boson at CERN's Large Hadron Collider, Europe has assumed world leadership in this field. A combination of fiscal austerity, continuing SSC cost overruns, intense Congressional scrutiny, lack of major foreign contributions, waning Presidential support, and the widespread public perception of mismanagement led to the project's demise nearly five years after it had begun. Its termination occurred against the political backdrop of changing scientific needs as US science policy shifted to a post-Cold War footing during the early 1990s. And the growing cost of the SSC inevitably exerted undue pressure upon other worthy research, thus weakening its support in Congress and the broader scientific community. As underscored by the Higgs boson discovery, at a mass substantially below that of the top quark, the SSC did not need to collide protons at 40 TeV in order to attain its premier physics goal. The selection of this design energy was governed more by politics than by physics, given that Europeans could build the LHC by eventually installing superconducting magnets in the LEP tunnel under construction in the mid-1980s. In hindsight, there were good alternative projects the US high-energy physics community could have pursued that did not involve building a gargantuan, multibillion-dollar machine at a green-field site in Texas. Research supported by the National Science Foundation, Department of Energy, and the Richard Lounsbery Foundation.

HOM-Free Linear Accelerating Structure for e+ e- Linear Collider at C-Band

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kubo, Kiyoshi

2003-07-07

HOM-free linear acceleration structure using the choke mode cavity (damped cavity) is now under design for e{sup +}e{sup -} linear collider project at C-band frequency (5712 MHz). Since this structure shows powerful damping effect on most of all HOMs, there is no multibunch problem due to long range wakefields. The structure will be equipped with the microwave absorbers in each cells and also the in-line dummy load in the last few cells. The straightness tolerance for 1.8 m long structure is closer than 30 {micro}m for 25% emittance dilution limit, which can be achieved by standard machining and braising techniques.more » Since it has good vacuum pumping conductance through annular gaps in each cell, instabilities due to the interaction of beam with the residual-gas and ions can be minimized.« less

Review of hydrodynamic tunneling issues in high power particle accelerators

NASA Astrophysics Data System (ADS)

Tahir, N. A.; Burkart, F.; Schmidt, R.; Shutov, A.; Piriz, A. R.

2018-07-01

Full impact of one Large Hadron Collider (LHC) 7 TeV proton beam on solid targets made of different materials including copper and carbon, was simulated using an energy deposition code, FLUKA and a two-dimensional hydrodynamic code, BIG2, iteratively. These studies showed that the penetration depth of the entire beam comprised of 2808 proton bunches significantly increases due to a phenomenon named hydrodynamic tunneling of the protons and the shower. For example, the static range of a single 7 TeV proton and its shower is about 1 m in solid copper, but the full LHC beam will penetrate up to about 35 m in the target, if the hydrodynamic effects were included. Due to the potential implications of this result on the machine protection considerations, it was decided to have an experimental verification of the hydrodynamic tunneling effect. For this purpose, experiments were carried out at the CERN HiRadMat (High Radiation to Materials) facility in which extended solid copper cylindrical targets were irradiated with the 440 GeV proton beam generated by the Super Proton Synchrotron (SPS). Simulations of beam-target heating considering the same beam parameters that were used in the experiments, were also performed. These experiments not only confirmed the existence of the hydrodynamic tunneling, but the experimental measurements showed very good agreement with the experimental results as well. This provided confidence in the work on LHC related beam-matter heating simulations. Currently, a design study is being carried out by the international community (with CERN taking the leading role) for a post LHC collider named, the Future Circular Collider (FCC) which will accelerate two counter rotating proton beams up to a particle energy of 50 TeV. Simulations of the full impact of one FCC beam comprised of 10,600 proton bunches with a solid copper target have also been done. These simulations have shown that although the static range of a single 50 TeV proton and its shower in solid copper is around 1.8 m, the entire beam will penetrate up to about 350 m in the target. Feasibility studies of developing a water beam dump for the FCC have also been carried out. A review of this work and its implications on machine protection system are presented in this paper.

PREFACE: Hot Quarks 2014: Workshop for young scientists on the physics of ultrarelativistic nucleus-nucleus collisions

NASA Astrophysics Data System (ADS)

2015-05-01

The 6th edition of the Workshop for Young Scientists on the Physics of Ultrarelativistic Nucleus-Nucleus Collisions (Hot Quarks 2014) was held in Las Negras, Spain from 21-28 September 2014. Following the traditions of the conference, this meeting gathered more than 70 participants in the first years of their scientific careers. The present issue contains the proceedings of this workshop. As in the past, the Hot Quarks workshop offered a unique atmosphere for a lively discussion and interpretation of the current measurements from high energy nuclear collisions. Recent results and upgrades at CERN's Large Hadron Collider (LHC) and Brookhaven's Relativistic Heavy Ion Collider (RHIC) were presented. Recent theoretical developments were also extensively discussed as well as the perspectives for future facilities such as the Facility for Antiproton and Ion Research (FAIR) at Darmstadt and the Electron-Ion Collider at Brookhaven. The conference's goal to provide a platform for young researchers to learn and foster their interactions was successfully met. We wish to thank the sponsors of the Hot Quarks 2014 Conference, who supported the authors of this volume: Brookhaven National Laboratory (USA), CPAN (Spain), Czech Science Foundation (GACR) under grant 13-20841S (Czech Republic), European Laboratory for Particle Physics CERN (Switzerland), European Research Council under grant 259612 (EU), ExtreMe Matter Institute EMMI (Germany), Helmholtz Association and GSI under grant VH-NG-822, Helmholtz International Center for FAIR (Germany), National Science Foundation under grant No.1359622 (USA), Nuclear Physics Institute ASCR (Czech Republic), Patronato de la Alhambra y Generalife (Spain) and the Universidad de Granada (Spain). Javier López Albacete, Universidad de Granada (Spain) Jana Bielcikova, Nuclear Physics Inst. and Academy of Sciences (Czech Republic) Rainer J. Fries, Texas A&M University (USA) Raphaël Granier de Cassagnac, CNRS-IN2P3 and École polytechnique (France) Boris Hippolyte, CNRS-IN2P3 and Université de Strasbourg (France) Jiangyong Jia, Stony Brook University and Brookhaven National Laboratory (USA) André Mischke, Utrecht University and Nikhef Amsterdam (The Netherlands) Ágnes Mócsy, Pratt Institute and Brookhaven National Laboratory (USA) Hannah Petersen, Goethe University, FIAS and GSI (Germany) Lijuan Ruan, Brookhaven National Laboratory (USA) Sevil Salur, Rutgers University, (USA)

Fourth standard model family neutrino at future linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ciftci, A.K.; Ciftci, R.; Sultansoy, S.

2005-09-01

It is known that flavor democracy favors the existence of the fourth standard model (SM) family. In order to give nonzero masses for the first three-family fermions flavor democracy has to be slightly broken. A parametrization for democracy breaking, which gives the correct values for fundamental fermion masses and, at the same time, predicts quark and lepton Cabibbo-Kobayashi-Maskawa (CKM) matrices in a good agreement with the experimental data, is proposed. The pair productions of the fourth SM family Dirac ({nu}{sub 4}) and Majorana (N{sub 1}) neutrinos at future linear colliders with {radical}(s)=500 GeV, 1 TeV, and 3 TeV are considered.more » The cross section for the process e{sup +}e{sup -}{yields}{nu}{sub 4}{nu}{sub 4}(N{sub 1}N{sub 1}) and the branching ratios for possible decay modes of the both neutrinos are determined. The decays of the fourth family neutrinos into muon channels ({nu}{sub 4}(N{sub 1}){yields}{mu}{sup {+-}}W{sup {+-}}) provide cleanest signature at e{sup +}e{sup -} colliders. Meanwhile, in our parametrization this channel is dominant. W bosons produced in decays of the fourth family neutrinos will be seen in detector as either di-jets or isolated leptons. As an example, we consider the production of 200 GeV mass fourth family neutrinos at {radical}(s)=500 GeV linear colliders by taking into account di-muon plus four jet events as signatures.« less

Zeroth-order design report for the next linear collider. Volume 2

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raubenheimer, T.O.

This Zeroth-Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The ``design`` presented here is not fully engineered in any sense, but to be assured that the NLCmore » can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume II covers the following: collimation systems; IP switch and big bend; final focus; the interaction region; multiple bunch issues; control systems; instrumentation; machine protection systems; NLC reliability considerations; NLC conventional facilities. Also included are four appendices on the following topics: An RF power source upgrade to the NLC; a second interaction region for gamma-gamma, gamma-electron; ground motion: theory and measurement; and beam-based feedback: theory and implementation.« less

Superstrong Adjustable Permanent Magnet for a Linear Collider Final Focus

DOE Office of Scientific and Technical Information (OSTI.GOV)

Mihara, T.

A superstrong permanent magnet quadrupole (PMQ) is one of the candidates for the final focus lens for the linear collider because of its compactness and low power consumption. The first fabricated prototype of our PMQ achieved a 300T/m superstrong field gradient with a 100mm overall magnet radius and a 7mm bore radius, but a drawback is its fixed strength. Therefore, a second prototype of PMQ, whose strength is adjustable, was fabricated. Its strength adjustability is based on the ''double ring structure'', rotating subdivided magnet slices separately. This second prototype is being tested. Some of the early results are presented.

Heavy neutrino mixing and single production at linear collider

NASA Astrophysics Data System (ADS)

Gluza, J.; Maalampi, J.; Raidal, M.; Zrałek, M.

1997-02-01

We study the single production of heavy neutrinos via the processes e- e+ -> νN and e- γ -> W- N at future linear colliders. As a base of our considerations we take a wide class of models, both with vanishing and non-vanishing left-handed Majorana neutrino mass matrix mL. We perform a model independent analyses of the existing experimental data and find connections between the characteristic of heavy neutrinos (masses, mixings, CP eigenvalues) and the mL parameters. We show that with the present experimental constraints heavy neutrino masses almost up to the collision energy can be tested in the future experiments.

The International Linear Collider Technical Design Report - Volume 3.II: Accelerator Baseline Design

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adolphsen, Chris

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carriedmore » out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.« less

The International Linear Collider Technical Design Report - Volume 1: Executive Summary

DOE Office of Scientific and Technical Information (OSTI.GOV)

Behnke, Ties; Brau, James E.; Foster, Brian

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carriedmore » out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.« less

The International Linear Collider Technical Design Report - Volume 3.I: Accelerator \\& in the Technical Design Phase

DOE Office of Scientific and Technical Information (OSTI.GOV)

Adolphsen, Chris

2013-06-26

The International Linear Collider Technical Design Report (TDR) describes in four volumes the physics case and the design of a 500 GeV centre-of-mass energy linear electron-positron collider based on superconducting radio-frequency technology using Niobium cavities as the accelerating structures. The accelerator can be extended to 1 TeV and also run as a Higgs factory at around 250 GeV and on the Z0 pole. A comprehensive value estimate of the accelerator is give, together with associated uncertainties. It is shown that no significant technical issues remain to be solved. Once a site is selected and the necessary site-dependent engineering is carriedmore » out, construction can begin immediately. The TDR also gives baseline documentation for two high-performance detectors that can share the ILC luminosity by being moved into and out of the beam line in a "push-pull" configuration. These detectors, ILD and SiD, are described in detail. They form the basis for a world-class experimental programme that promises to increase significantly our understanding of the fundamental processes that govern the evolution of the Universe.« less

Cryogenic Design of the New High Field Magnet Test Facility at CERN

NASA Astrophysics Data System (ADS)

Benda, V.; Pirotte, O.; De Rijk, G.; Bajko, M.; Craen, A. Vande; Perret, Ph.; Hanzelka, P.

In the framework of the R&D program related to the Large Hadron Collider (LHC) upgrades, a new High Field Magnet (HFM) vertical test bench is required. This facility located in the SM18 cryogenic test hall shall allow testing of up to 15 tons superconducting magnets with energy up to 10 MJ in a temperature range between 1.9 K and 4.5 K. The article describes the cryogenic architecture to be inserted in the general infrastructure of SM18 including the process and instrumentation diagram, the different operating phases including strategy for magnet cool down and warm up at controlled speed and quench management as well as the design of the main components.

Resistive Plate Chambers for imaging calorimetry — The DHCAL

NASA Astrophysics Data System (ADS)

Repond, J.

2014-09-01

The DHCAL — the Digital Hadron Calorimeter — is a prototype calorimeter based on Resistive Plate Chambers (RPCs). The design emphasizes the imaging capabilities of the detector in an effort to optimize the calorimeter for the application of Particle Flow Algorithms (PFAs) to the reconstruction of hadronic jet energies in a colliding beam environment. The readout of the chambers is segmented into 1 × 1 cm2 pads, each read out with a 1-bit (single threshold) resolution. The prototype with approximately 500,000 readout channels underwent extensive testing in both the Fermilab and CERN test beams. This talk presents preliminary findings from the analysis of data collected at the test beams.

From the Proton Synchroton to the Large Hadron Collider - 50 Years of Nobel Memories in High-Energy Physics

ScienceCinema

None

2018-06-19

The seminars will be held in the Main Auditorium with transmission to : Council Chamber, IT Auditorium, Prévessin BE Auditorium , Kjell Johnssen Auditorium in Building 30, Room 40-S2-A01, and via webcast. Confirmed Speakers include: Prof. Jack Steinberger, Dr. Guenther Plass, Prof. Emilio Picasso, Dr. Steve Myers, Prof. Carlo Rubbia, Prof. Burton Richter, Dr. Lyndon Evans, Prof. Rolf-Dieter Heuer, Prof. Leon Lederman, Prof. Jim Cronin, Prof. Sheldon Glashow, Prof. Jerome Friedman, Prof. Frank Wilczek, Prof. Martinus Veltman, Prof. Gerardus 't Hooft, Prof. David Gross, Prof. Samuel Ting, Prof. Steven Weinberg (via teleconference) --- Contact: Directorate.Office@cern.ch

From the Proton Synchroton to the Large Hadron Collider - 50 Years of Nobel Memories in High-Energy Physics

ScienceCinema

Friedman, Jerome

2018-06-15

The seminars will be held in the Main Auditorium with transmission to : Council Chamber, IT Auditorium, Prévessin BE Auditorium , Kjell Johnssen Auditorium in Building 30, Room 40-S2-A01, and via webcast. Confirmed Speakers include: Prof. Jack Steinberger, Dr. Guenther Plass, Prof. Emilio Picasso, Dr. Steve Myers, Prof. Carlo Rubbia, Prof. Burton Richter, Dr. Lyndon Evans, Prof. Rolf-Dieter Heuer, Prof. Leon Lederman, Prof. Jim Cronin, Prof. Sheldon Glashow, Prof. Jerome Friedman, Prof. Frank Wilczek, Prof. Martinus Veltman, Prof. Gerardus 't Hooft, Prof. David Gross, Prof. Samuel Ting, Prof. Steven Weinberg (via teleconference) --- Contact: Directorate.Office@cern.ch

Measurement of shower development and its Molière radius with a four-plane LumiCal test set-up

NASA Astrophysics Data System (ADS)

Abramowicz, H.; Abusleme, A.; Afanaciev, K.; Benhammou, Y.; Bortko, L.; Borysov, O.; Borysova, M.; Bozovic-Jelisavcic, I.; Chelkov, G.; Daniluk, W.; Dannheim, D.; Elsener, K.; Firlej, M.; Firu, E.; Fiutowski, T.; Ghenescu, V.; Gostkin, M.; Hempel, M.; Henschel, H.; Idzik, M.; Ignatenko, A.; Ishikawa, A.; Kananov, S.; Karacheban, O.; Klempt, W.; Kotov, S.; Kotula, J.; Kozhevnikov, D.; Kruchonok, V.; Krupa, B.; Kulis, Sz.; Lange, W.; Leonard, J.; Lesiak, T.; Levy, A.; Levy, I.; Lohmann, W.; Lukic, S.; Moron, J.; Moszczynski, A.; Neagu, A. T.; Nuiry, F.-X.; Pandurovic, M.; Pawlik, B.; Preda, T.; Rosenblat, O.; Sailer, A.; Schumm, B.; Schuwalow, S.; Smiljanic, I.; Smolyanskiy, P.; Swientek, K.; Terlecki, P.; Uggerhoj, U. I.; Wistisen, T. N.; Wojton, T.; Yamamoto, H.; Zawiejski, L.; Zgura, I. S.; Zhemchugov, A.

2018-02-01

A prototype of a luminometer, designed for a future e^+e^- collider detector, and consisting at present of a four-plane module, was tested in the CERN PS accelerator T9 beam. The objective of this beam test was to demonstrate a multi-plane tungsten/silicon operation, to study the development of the electromagnetic shower and to compare it with MC simulations. The Molière radius has been determined to be 24.0 ± 0.6 (stat.) ± 1.5 (syst.) mm using a parametrization of the shower shape. Very good agreement was found between data and a detailed Geant4 simulation.

Applying physical science techniques and CERN technology to an unsolved problem in radiation treatment for cancer: the multidisciplinary ‘VoxTox’ research programme

PubMed Central

Burnet, Neil G; Scaife, Jessica E; Romanchikova, Marina; Thomas, Simon J; Bates, Amy M; Wong, Emma; Noble, David J; Shelley, Leila EA; Bond, Simon J; Forman, Julia R; Hoole, Andrew CF; Barnett, Gillian C; Brochu, Frederic M; Simmons, Michael PD; Jena, Raj; Harrison, Karl; Yeap, Ping Lin; Drew, Amelia; Silvester, Emma; Elwood, Patrick; Pullen, Hannah; Sultana, Andrew; Seah, Shannon YK; Wilson, Megan Z; Russell, Simon G; Benson, Richard J; Rimmer, Yvonne L; Jefferies, Sarah J; Taku, Nicolette; Gurnell, Mark; Powlson, Andrew S; Schönlieb, Carola-Bibiane; Cai, Xiaohao; Sutcliffe, Michael PF; Parker, Michael A

2017-01-01

The VoxTox research programme has applied expertise from the physical sciences to the problem of radiotherapy toxicity, bringing together expertise from engineering, mathematics, high energy physics (including the Large Hadron Collider), medical physics and radiation oncology. In our initial cohort of 109 men treated with curative radiotherapy for prostate cancer, daily image guidance computed tomography (CT) scans have been used to calculate delivered dose to the rectum, as distinct from planned dose, using an automated approach. Clinical toxicity data have been collected, allowing us to address the hypothesis that delivered dose provides a better predictor of toxicity than planned dose. PMID:29177202

Measurement of the W +W - cross section in √s = 7 TeV pp collisions with ATLAS

DOE PAGES

Aad, Georges

2011-07-20

This Letter presents a measurement of the W +W - production cross section in √s = 7 TeV pp collisions by the ATLAS experiment, using 34 inverse pb -1 of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7±0.6 events. The measured cross section is 41 +20 -16(stat) ± 5(syst) ± 1(lumi) pb, which is consistent with the standard model prediction of 44 ± 3 pb calculated at next-to-leading order in QCD.

From the Proton Synchroton to the Large Hadron Collider - 50 Years of Nobel Memories in High-Energy Physics

DOE Office of Scientific and Technical Information (OSTI.GOV)

None

2009-12-07

The seminars will be held in the Main Auditorium with transmission to : Council Chamber, IT Auditorium, Prévessin BE Auditorium , Kjell Johnssen Auditorium in Building 30, Room 40-S2-A01, and via webcast. Confirmed Speakers include: Prof. Jack Steinberger, Dr. Guenther Plass, Prof. Emilio Picasso, Dr. Steve Myers, Prof. Carlo Rubbia, Prof. Burton Richter, Dr. Lyndon Evans, Prof. Rolf-Dieter Heuer, Prof. Leon Lederman, Prof. Jim Cronin, Prof. Sheldon Glashow, Prof. Jerome Friedman, Prof. Frank Wilczek, Prof. Martinus Veltman, Prof. Gerardus 't Hooft, Prof. David Gross, Prof. Samuel Ting, Prof. Steven Weinberg (via teleconference) --- Contact: Directorate.Office@cern.ch

Performance of the CMS Event Builder

NASA Astrophysics Data System (ADS)

Andre, J.-M.; Behrens, U.; Branson, J.; Brummer, P.; Chaze, O.; Cittolin, S.; Contescu, C.; Craigs, B. G.; Darlea, G.-L.; Deldicque, C.; Demiragli, Z.; Dobson, M.; Doualot, N.; Erhan, S.; Fulcher, J. F.; Gigi, D.; Gładki, M.; Glege, F.; Gomez-Ceballos, G.; Hegeman, J.; Holzner, A.; Janulis, M.; Jimenez-Estupiñán, R.; Masetti, L.; Meijers, F.; Meschi, E.; Mommsen, R. K.; Morovic, S.; O'Dell, V.; Orsini, L.; Paus, C.; Petrova, P.; Pieri, M.; Racz, A.; Reis, T.; Sakulin, H.; Schwick, C.; Simelevicius, D.; Zejdl, P.

2017-10-01

The data acquisition system (DAQ) of the CMS experiment at the CERN Large Hadron Collider assembles events at a rate of 100 kHz, transporting event data at an aggregate throughput of {\\mathscr{O}}(100 {{GB}}/{{s}}) to the high-level trigger farm. The DAQ architecture is based on state-of-the-art network technologies for the event building. For the data concentration, 10/40 Gbit/s Ethernet technologies are used together with a reduced TCP/IP protocol implemented in FPGA for a reliable transport between custom electronics and commercial computing hardware. A 56 Gbit/s Infiniband FDR Clos network has been chosen for the event builder. This paper presents the implementation and performance of the event-building system.

Reliability and degradation of oxide VCSELs due to reaction to atmospheric water vapor

NASA Astrophysics Data System (ADS)

Dafinca, Alexandru; Weidberg, Anthony R.; McMahon, Steven J.; Grillo, Alexander A.; Farthouat, Philippe; Ziolkowski, Michael; Herrick, Robert W.

2013-03-01

850nm oxide-aperture VCSELs are susceptible to premature failure if operated while exposed to atmospheric water vapor, and not protected by hermetic packaging. The ATLAS detector in CERN's Large Hadron Collider (LHC) has had approximately 6000 channels of Parallel Optic VCSELs fielded under well-documented ambient conditions. Exact time-to-failure data has been collected on this large sample, providing for the first time actual failure data at use conditions. In addition, the same VCSELs were tested under a variety of accelerated conditions to allow us to construct a more accurate acceleration model. Failure analysis information will also be presented to show what we believe causes corrosion-related failure for such VCSELs.

From the Proton Synchroton to the Large Hadron Collider - 50 Years of Nobel Memories in High-Energy Physics

ScienceCinema

None

2017-12-09

The seminars will be held in the Main Auditorium with transmission to : Council Chamber, IT Auditorium, Prévessin BE Auditorium , Kjell Johnssen Auditorium in Building 30, Room 40-S2-A01, and via webcast. Confirmed Speakers include: Prof. Jack Steinberger, Dr. Guenther Plass, Prof. Emilio Picasso, Dr. Steve Myers, Prof. Carlo Rubbia, Prof. Burton Richter, Dr. Lyndon Evans, Prof. Rolf-Dieter Heuer, Prof. Leon Lederman, Prof. Jim Cronin, Prof. Sheldon Glashow, Prof. Jerome Friedman, Prof. Frank Wilczek, Prof. Martinus Veltman, Prof. Gerardus 't Hooft, Prof. David Gross, Prof. Samuel Ting, Prof. Steven Weinberg (via teleconference) --- Contact: Directorate.Office@cern.ch

Measurement of the W+W- Cross Section in s=7TeV pp Collisions with ATLAS

NASA Astrophysics Data System (ADS)

Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; Acerbi, E.; Acharya, B. S.; Adams, D. L.; Addy, T. N.; Adelman, J.; Aderholz, M.; Adomeit, S.; Adragna, P.; Adye, T.; Aefsky, S.; Aguilar-Saavedra, J. A.; Aharrouche, M.; Ahlen, S. P.; Ahles, F.; Ahmad, A.; Ahsan, M.; Aielli, G.; Akdogan, T.; Åkesson, T. P. A.; Akimoto, G.; Akimov, A. V.; Akiyama, A.; Alam, M. S.; Alam, M. A.; Albrand, S.; Aleksa, M.; Aleksandrov, I. N.; Alessandria, F.; Alexa, C.; Alexander, G.; Alexandre, G.; Alexopoulos, T.; Alhroob, M.; Aliev, M.; Alimonti, G.; Alison, J.; Aliyev, M.; Allport, P. P.; Allwood-Spiers, S. E.; Almond, J.; Aloisio, A.; Alon, R.; Alonso, A.; Alviggi, M. G.; Amako, K.; Amaral, P.; Amelung, C.; Ammosov, V. V.; Amorim, A.; Amorós, G.; Amram, N.; Anastopoulos, C.; Andeen, T.; Anders, C. F.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Andrieux, M.-L.; Anduaga, X. S.; Angerami, A.; Anghinolfi, F.; Anjos, N.; Annovi, A.; Antonaki, A.; Antonelli, M.; Antonelli, S.; Antonov, A.; Antos, J.; Anulli, F.; Aoun, S.; Aperio Bella, L.; Apolle, R.; Arabidze, G.; Aracena, I.; Arai, Y.; Arce, A. T. H.; Archambault, J. P.; Arfaoui, S.; Arguin, J.-F.; Arik, E.; Arik, M.; Armbruster, A. J.; Arnaez, O.; Arnault, C.; Artamonov, A.; Artoni, G.; Arutinov, D.; Asai, S.; Asfandiyarov, R.; Ask, S.; Åsman, B.; Asquith, L.; Assamagan, K.; Astbury, A.; Astvatsatourov, A.; Atoian, G.; Aubert, B.; Auerbach, B.; Auge, E.; Augsten, K.; Aurousseau, M.; Austin, N.; Avramidou, R.; Axen, D.; Ay, C.; Azuelos, G.; Azuma, Y.; Baak, M. A.; Baccaglioni, G.; Bacci, C.; Bach, A. M.; Bachacou, H.; Bachas, K.; Bachy, G.; Backes, M.; Backhaus, M.; Badescu, E.; Bagnaia, P.; Bahinipati, S.; Bai, Y.; Bailey, D. C.; Bain, T.; Baines, J. T.; Baker, O. K.; Baker, M. D.; Baker, S.; Baltasar Dos Santos Pedrosa, F.; Banas, E.; Banerjee, P.; Banerjee, Sw.; Banfi, D.; Bangert, A.; Bansal, V.; Bansil, H. S.; Barak, L.; Baranov, S. P.; Barashkou, A.; Barbaro Galtieri, A.; Barber, T.; Barberio, E. L.; Barberis, D.; Barbero, M.; Bardin, D. Y.; Barillari, T.; Barisonzi, M.; Barklow, T.; Barlow, N.; Barnett, B. M.; Barnett, R. M.; Baroncelli, A.; Barr, A. J.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Barrillon, P.; Bartoldus, R.; Barton, A. E.; Bartsch, D.; Bartsch, V.; Bates, R. L.; Batkova, L.; Batley, J. R.; Battaglia, A.; Battistin, M.; Battistoni, G.; Bauer, F.; Bawa, H. S.; Beare, B.; Beau, T.; Beauchemin, P. H.; Beccherle, R.; Bechtle, P.; Beck, H. P.; Beckingham, M.; Becks, K. H.; Beddall, A. J.; Beddall, A.; Bedikian, S.; Bednyakov, V. A.; Bee, C. P.; Begel, M.; Behar Harpaz, S.; Behera, P. K.; Beimforde, M.; Belanger-Champagne, C.; Bell, P. J.; Bell, W. H.; Bella, G.; Bellagamba, L.; Bellina, F.; Bellomo, M.; Belloni, A.; Beloborodova, O.; Belotskiy, K.; Beltramello, O.; Ben Ami, S.; Benary, O.; Benchekroun, D.; Benchouk, C.; Bendel, M.; Benedict, B. H.; Benekos, N.; Benhammou, Y.; Benjamin, D. P.; Benoit, M.; Bensinger, J. R.; Benslama, K.; Bentvelsen, S.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Berghaus, F.; Berglund, E.; Beringer, J.; Bernardet, K.; Bernat, P.; Bernhard, R.; Bernius, C.; Berry, T.; Bertin, A.; Bertinelli, F.; Bertolucci, F.; Besana, M. I.; Besson, N.; Bethke, S.; Bhimji, W.; Bianchi, R. M.; Bianco, M.; Biebel, O.; Bieniek, S. P.; Biesiada, J.; Biglietti, M.; Bilokon, H.; Bindi, M.; Binet, S.; Bingul, A.; Bini, C.; Biscarat, C.; Bitenc, U.; Black, K. M.; Blair, R. E.; Blanchard, J.-B.; Blanchot, G.; Blazek, T.; Blocker, C.; Blocki, J.; Blondel, A.; Blum, W.; Blumenschein, U.; Bobbink, G. J.; Bobrovnikov, V. B.; Bocchetta, S. S.; Bocci, A.; Boddy, C. R.; Boehler, M.; Boek, J.; Boelaert, N.; Böser, S.; Bogaerts, J. A.; Bogdanchikov, A.; Bogouch, A.; Bohm, C.; Boisvert, V.; Bold, T.; Boldea, V.; Bolnet, N. M.; Bona, M.; Bondarenko, V. G.; Boonekamp, M.; Boorman, G.; Booth, C. N.; Bordoni, S.; Borer, C.; Borisov, A.; Borissov, G.; Borjanovic, I.; Borroni, S.; Bos, K.; Boscherini, D.; Bosman, M.; Boterenbrood, H.; Botterill, D.; Bouchami, J.; Boudreau, J.; Bouhova-Thacker, E. V.; Boulahouache, C.; Bourdarios, C.; Bousson, N.; Boveia, A.; Boyd, J.; Boyko, I. R.; Bozhko, N. I.; Bozovic-Jelisavcic, I.; Bracinik, J.; Braem, A.; Branchini, P.; Brandenburg, G. W.; Brandt, A.; Brandt, G.; Brandt, O.; Bratzler, U.; Brau, B.; Brau, J. E.; Braun, H. M.; Brelier, B.; Bremer, J.; Brenner, R.; Bressler, S.; Breton, D.; Britton, D.; Brochu, F. M.; Brock, I.; Brock, R.; Brodbeck, T. J.; Brodet, E.; Broggi, F.; Bromberg, C.; Brooijmans, G.; Brooks, W. K.; Brown, G.; Brown, H.; Brubaker, E.; Bruckman de Renstrom, P. A.; Bruncko, D.; Bruneliere, R.; Brunet, S.; Bruni, A.; Bruni, G.; Bruschi, M.; Buanes, T.; Bucci, F.; Buchanan, J.; Buchanan, N. J.; Buchholz, P.; Buckingham, R. M.; Buckley, A. G.; Buda, S. I.; Budagov, I. A.; Budick, B.; Büscher, V.; Bugge, L.; Buira-Clark, D.; Bulekov, O.; Bunse, M.; Buran, T.; Burckhart, H.; Burdin, S.; Burgess, T.; Burke, S.; Busato, E.; Bussey, P.; Buszello, C. P.; Butin, F.; Butler, B.; Butler, J. M.; Buttar, C. M.; Butterworth, J. M.; Buttinger, W.; Byatt, T.; Cabrera Urbán, S.; Caforio, D.; Cakir, O.; Calafiura, P.; Calderini, G.; Calfayan, P.; Calkins, R.; Caloba, L. P.; Caloi, R.; Calvet, D.; Calvet, S.; Camacho Toro, R.; Camard, A.; Camarri, P.; Cambiaghi, M.; Cameron, D.; Cammin, J.; Campana, S.; Campanelli, M.; Canale, V.; Canelli, F.; Canepa, A.; Cantero, J.; Capasso, L.; Capeans Garrido, M. D. M.; Caprini, I.; Caprini, M.; Capriotti, D.; Capua, M.; Caputo, R.; Caramarcu, C.; Cardarelli, R.; Carli, T.; Carlino, G.; Carminati, L.; Caron, B.; Caron, S.; Carrillo Montoya, G. D.; Carter, A. A.; Carter, J. R.; Carvalho, J.; Casadei, D.; Casado, M. P.; Cascella, M.; Caso, C.; Castaneda Hernandez, A. M.; Castaneda-Miranda, E.; Castillo Gimenez, V.; Castro, N. F.; Cataldi, G.; Cataneo, F.; Catinaccio, A.; Catmore, J. R.; Cattai, A.; Cattani, G.; Caughron, S.; Cauz, D.; Cavalleri, P.; Cavalli, D.; Cavalli-Sforza, M.; Cavasinni, V.; Cazzato, A.; Ceradini, F.; Cerqueira, A. S.; Cerri, A.; Cerrito, L.; Cerutti, F.; Cetin, S. A.; Cevenini, F.; Chafaq, A.; Chakraborty, D.; Chan, K.; Chapleau, B.; Chapman, J. D.; Chapman, J. W.; Chareyre, E.; Charlton, D. G.; Chavda, V.; Cheatham, S.; Chekanov, S.; Chekulaev, S. V.; Chelkov, G. A.; Chelstowska, M. A.; Chen, C.; Chen, H.; Chen, L.; Chen, S.; Chen, T.; Chen, X.; Cheng, S.; Cheplakov, A.; Chepurnov, V. F.; Cherkaoui El Moursli, R.; Chernyatin, V.; Cheu, E.; Cheung, S. L.; Chevalier, L.; Chiefari, G.; Chikovani, L.; Childers, J. T.; Chilingarov, A.; Chiodini, G.; Chizhov, M. V.; Choudalakis, G.; Chouridou, S.; Christidi, I. A.; Christov, A.; Chromek-Burckhart, D.; Chu, M. L.; Chudoba, J.; Ciapetti, G.; Ciba, K.; Ciftci, A. K.; Ciftci, R.; Cinca, D.; Cindro, V.; Ciobotaru, M. D.; Ciocca, C.; Ciocio, A.; Cirilli, M.; Ciubancan, M.; Clark, A.; Clark, P. J.; Cleland, W.; Clemens, J. C.; Clement, B.; Clement, C.; Clifft, R. W.; Coadou, Y.; Cobal, M.; Coccaro, A.; Cochran, J.; Coe, P.; Cogan, J. G.; Coggeshall, J.; Cogneras, E.; Cojocaru, C. D.; Colas, J.; Colijn, A. P.; Collard, C.; Collins, N. J.; Collins-Tooth, C.; Collot, J.; Colon, G.; Conde Muiño, P.; Coniavitis, E.; Conidi, M. C.; Consonni, M.; Constantinescu, S.; Conta, C.; Conventi, F.; Cook, J.; Cooke, M.; Cooper, B. D.; Cooper-Sarkar, A. M.; Cooper-Smith, N. J.; Copic, K.; Cornelissen, T.; Corradi, M.; Corriveau, F.; Cortes-Gonzalez, A.; Cortiana, G.; Costa, G.; Costa, M. J.; Costanzo, D.; Costin, T.; Côté, D.; Coura Torres, R.; Courneyea, L.; Cowan, G.; Cowden, C.; Cox, B. E.; Cranmer, K.; Crescioli, F.; Cristinziani, M.; Crosetti, G.; Crupi, R.; Crépé-Renaudin, S.; Cuciuc, C.-M.; Cuenca Almenar, C.; Cuhadar Donszelmann, T.; Cuneo, S.; Curatolo, M.; Curtis, C. J.; Cwetanski, P.; Czirr, H.; Czyczula, Z.; D'Auria, S.; D'Onofrio, M.; D'Orazio, A.; da Rocha Gesualdi Mello, A.; da Silva, P. V. M.; da Via, C.; Dabrowski, W.; Dahlhoff, A.; Dai, T.; Dallapiccola, C.; Dam, M.; Dameri, M.; Damiani, D. S.; Danielsson, H. O.; Dannheim, D.; Dao, V.; Darbo, G.; Darlea, G. L.; Daum, C.; Dauvergne, J. P.; Davey, W.; Davidek, T.; Davidson, N.; Davidson, R.; Davies, M.; Davison, A. R.; Dawe, E.; Dawson, I.; Dawson, J. W.; Daya, R. K.; de, K.; de Asmundis, R.; de Castro, S.; de Castro Faria Salgado, P. E.; de Cecco, S.; de Graat, J.; de Groot, N.; de Jong, P.; de La Taille, C.; de la Torre, H.; de Lotto, B.; de Mora, L.; de Nooij, L.; de Oliveira Branco, M.; de Pedis, D.; de Saintignon, P.; de Salvo, A.; de Sanctis, U.; de Santo, A.; de Vivie de Regie, J. B.; Dean, S.; Dedovich, D. V.; Degenhardt, J.; Dehchar, M.; Deile, M.; Del Papa, C.; Del Peso, J.; Del Prete, T.; Dell'Acqua, A.; Dell'Asta, L.; Della Pietra, M.; Della Volpe, D.; Delmastro, M.; Delpierre, P.; Delruelle, N.; Delsart, P. A.; Deluca, C.; Demers, S.; Demichev, M.; Demirkoz, B.; Deng, J.; Denisov, S. P.; Derendarz, D.; Derkaoui, J. E.; Derue, F.; Dervan, P.; Desch, K.; Devetak, E.; Deviveiros, P. O.; Dewhurst, A.; Dewilde, B.; Dhaliwal, S.; Dhullipudi, R.; di Ciaccio, A.; di Ciaccio, L.; di Girolamo, A.; di Girolamo, B.; di Luise, S.; di Mattia, A.; di Micco, B.; di Nardo, R.; di Simone, A.; di Sipio, R.; Diaz, M. A.; Diblen, F.; Diehl, E. B.; Dietl, H.; Dietrich, J.; Dietzsch, T. A.; Diglio, S.; Dindar Yagci, K.; Dingfelder, J.; Dionisi, C.; Dita, P.; Dita, S.; Dittus, F.; Djama, F.; Djilkibaev, R.; Djobava, T.; Do Vale, M. A. B.; Do Valle Wemans, A.; Doan, T. K. O.; Dobbs, M.; Dobinson, R.; Dobos, D.; Dobson, E.; Dobson, M.; Dodd, J.; Dogan, O. B.; Doglioni, C.; Doherty, T.; Doi, Y.; Dolejsi, J.; Dolenc, I.; Dolezal, Z.; Dolgoshein, B. A.; Dohmae, T.; Donadelli, M.; Donega, M.; Donini, J.; Dopke, J.; Doria, A.; Dos Anjos, A.; Dosil, M.; Dotti, A.; Dova, M. T.; Dowell, J. D.; Doxiadis, A. D.; Doyle, A. T.; Drasal, Z.; Drees, J.; Dressnandt, N.; Drevermann, H.; Driouichi, C.; Dris, M.; Dubbert, J.; Dubbs, T.; Dube, S.; Duchovni, E.; Duckeck, G.; Dudarev, A.; Dudziak, F.; Dührssen, M.; Duerdoth, I. P.; Duflot, L.; Dufour, M.-A.; Dunford, M.; Duran Yildiz, H.; Duxfield, R.; Dwuznik, M.; Dydak, F.; Dzahini, D.; Düren, M.; Ebenstein, W. L.; Ebke, J.; Eckert, S.; Eckweiler, S.; Edmonds, K.; Edwards, C. A.; Ehrenfeld, W.; Ehrich, T.; Eifert, T.; Eigen, G.; Einsweiler, K.; Eisenhandler, E.; Ekelof, T.; El Kacimi, M.; Ellert, M.; Elles, S.; Ellinghaus, F.; Ellis, K.; Ellis, N.; Elmsheuser, J.; Elsing, M.; Ely, R.; Emeliyanov, D.; Engelmann, R.; Engl, A.; Epp, B.; Eppig, A.; Erdmann, J.; Ereditato, A.; Eriksson, D.; Ernst, J.; Ernst, M.; Ernwein, J.; Errede, D.; Errede, S.; Ertel, E.; Escalier, M.; Escobar, C.; Espinal Curull, X.; Esposito, B.; Etienne, F.; Etienvre, A. I.; Etzion, E.; Evangelakou, D.; Evans, H.; Fabbri, L.; Fabre, C.; Fakhrutdinov, R. M.; Falciano, S.; Falou, A. C.; Fang, Y.; Fanti, M.; Farbin, A.; Farilla, A.; Farley, J.; Farooque, T.; Farrington, S. M.; Farthouat, P.; Fassnacht, P.; Fassouliotis, D.; Fatholahzadeh, B.; Favareto, A.; Fayard, L.; Fazio, S.; Febbraro, R.; Federic, P.; Fedin, O. L.; Fedorko, I.; Fedorko, W.; Fehling-Kaschek, M.; Feligioni, L.; Fellmann, D.; Felzmann, C. U.; Feng, C.; Feng, E. J.; Fenyuk, A. B.; Ferencei, J.; Ferland, J.; Fernando, W.; Ferrag, S.; Ferrando, J.; Ferrara, V.; Ferrari, A.; Ferrari, P.; Ferrari, R.; Ferrer, A.; Ferrer, M. L.; Ferrere, D.; Ferretti, C.; Ferretto Parodi, A.; Fiascaris, M.; Fiedler, F.; Filipčič, A.; Filippas, A.; Filthaut, F.; Fincke-Keeler, M.; Fiolhais, M. C. N.; Fiorini, L.; Firan, A.; Fischer, G.; Fischer, P.; Fisher, M. J.; Fisher, S. M.; Flechl, M.; Fleck, I.; Fleckner, J.; Fleischmann, P.; Fleischmann, S.; Flick, T.; Flores Castillo, L. R.; Flowerdew, M. J.; Föhlisch, F.; Fokitis, M.; Fonseca Martin, T.; Forbush, D. A.; Formica, A.; Forti, A.; Fortin, D.; Foster, J. M.; Fournier, D.; Foussat, A.; Fowler, A. J.; Fowler, K.; Fox, H.; Francavilla, P.; Franchino, S.; Francis, D.; Frank, T.; Franklin, M.; Franz, S.; Fraternali, M.; Fratina, S.; French, S. T.; Froeschl, R.; Froidevaux, D.; Frost, J. A.; Fukunaga, C.; Fullana Torregrosa, E.; Fuster, J.; Gabaldon, C.; Gabizon, O.; Gadfort, T.; Gadomski, S.; Gagliardi, G.; Gagnon, P.; Galea, C.; Gallas, E. J.; Gallas, M. V.; Gallo, V.; Gallop, B. J.; Gallus, P.; Galyaev, E.; Gan, K. K.; Gao, Y. S.; Gapienko, V. A.; Gaponenko, A.; Garberson, F.; Garcia-Sciveres, M.; García, C.; García Navarro, J. E.; Gardner, R. W.; Garelli, N.; Garitaonandia, H.; Garonne, V.; Garvey, J.; Gatti, C.; Gaudio, G.; Gaumer, O.; Gaur, B.; Gauthier, L.; Gavrilenko, I. L.; Gay, C.; Gaycken, G.; Gayde, J.-C.; Gazis, E. N.; Ge, P.; Gee, C. N. P.; Geerts, D. A. A.; Geich-Gimbel, Ch.; Gellerstedt, K.; Gemme, C.; Gemmell, A.; Genest, M. H.; Gentile, S.; George, M.; George, S.; Gerlach, P.; Gershon, A.; Geweniger, C.; Ghazlane, H.; Ghez, P.; Ghodbane, N.; Giacobbe, B.; Giagu, S.; Giakoumopoulou, V.; Giangiobbe, V.; Gianotti, F.; Gibbard, B.; Gibson, A.; Gibson, S. M.; Gilbert, L. M.; Gilchriese, M.; Gilewsky, V.; Gillberg, D.; Gillman, A. R.; Gingrich, D. M.; Ginzburg, J.; Giokaris, N.; Giordano, R.; Giorgi, F. M.; Giovannini, P.; Giraud, P. F.; Giugni, D.; Giunta, M.; Giusti, P.; Gjelsten, B. K.; Gladilin, L. K.; Glasman, C.; Glatzer, J.; Glazov, A.; Glitza, K. W.; Glonti, G. L.; Godfrey, J.; Godlewski, J.; Goebel, M.; Göpfert, T.; Goeringer, C.; Gössling, C.; Göttfert, T.; Goldfarb, S.; Goldin, D.; Golling, T.; Golovnia, S. N.; Gomes, A.; Gomez Fajardo, L. S.; Gonçalo, R.; Goncalves Pinto Firmino da Costa, J.; Gonella, L.; Gonidec, A.; Gonzalez, S.; González de La Hoz, S.; Gonzalez Silva, M. L.; Gonzalez-Sevilla, S.; Goodson, J. J.; Goossens, L.; Gorbounov, P. A.; Gordon, H. A.; Gorelov, I.; Gorfine, G.; Gorini, B.; Gorini, E.; Gorišek, A.; Gornicki, E.; Gorokhov, S. A.; Goryachev, V. N.; Gosdzik, B.; Gosselink, M.; Gostkin, M. I.; Gouanère, M.; Gough Eschrich, I.; Gouighri, M.; Goujdami, D.; Goulette, M. P.; Goussiou, A. G.; Goy, C.; Grabowska-Bold, I.; Grabski, V.; Grafström, P.; Grah, C.; Grahn, K.-J.; Grancagnolo, F.; Grancagnolo, S.; Grassi, V.; Gratchev, V.; Grau, N.; Gray, H. M.; Gray, J. A.; Graziani, E.; Grebenyuk, O. G.; Greenfield, D.; Greenshaw, T.; Greenwood, Z. D.; Gregor, I. M.; Grenier, P.; Griesmayer, E.; Griffiths, J.; Grigalashvili, N.; Grillo, A. A.; Grinstein, S.; Gris, Ph.; Grishkevich, Y. V.; Grivaz, J.-F.; Grognuz, J.; Groh, M.; Gross, E.; Grosse-Knetter, J.; Groth-Jensen, J.; Grybel, K.; Guarino, V. J.; Guest, D.; Guicheney, C.; Guida, A.; Guillemin, T.; Guindon, S.; Guler, H.; Gunther, J.; Guo, B.; Guo, J.; Gupta, A.; Gusakov, Y.; Gushchin, V. N.; Gutierrez, A.; Gutierrez, P.; Guttman, N.; Gutzwiller, O.; Guyot, C.; Gwenlan, C.; Gwilliam, C. B.; Haas, A.; Haas, S.; Haber, C.; Hackenburg, R.; Hadavand, H. K.; Hadley, D. R.; Haefner, P.; Hahn, F.; Haider, S.; Hajduk, Z.; Hakobyan, H.; Haller, J.; Hamacher, K.; Hamal, P.; Hamilton, A.; Hamilton, S.; Han, H.; Han, L.; Hanagaki, K.; Hance, M.; Handel, C.; Hanke, P.; Hansen, J. R.; Hansen, J. B.; Hansen, J. D.; Hansen, P. H.; Hansson, P.; Hara, K.; Hare, G. A.; Harenberg, T.; Harkusha, S.; Harper, D.; Harrington, R. D.; Harris, O. M.; Harrison, K.; Hartert, J.; Hartjes, F.; Haruyama, T.; Harvey, A.; Hasegawa, S.; Hasegawa, Y.; Hassani, S.; Hatch, M.; Hauff, D.; Haug, S.; Hauschild, M.; Hauser, R.; Havranek, M.; Hawes, B. M.; Hawkes, C. M.; Hawkings, R. J.; Hawkins, D.; Hayakawa, T.; Hayden, D.; Hayward, H. S.; Haywood, S. J.; Hazen, E.; He, M.; Head, S. J.; Hedberg, V.; Heelan, L.; Heim, S.; Heinemann, B.; Heisterkamp, S.; Helary, L.; Heldmann, M.; Heller, M.; Hellman, S.; Helsens, C.; Henderson, R. C. W.; Henke, M.; Henrichs, A.; Henriques Correia, A. M.; Henrot-Versille, S.; Henry-Couannier, F.; Hensel, C.; Henß, T.; Hernandez, C. M.; Hernández Jiménez, Y.; Herrberg, R.; Hershenhorn, A. D.; Herten, G.; Hertenberger, R.; Hervas, L.; Hessey, N. P.; Hidvegi, A.; Higón-Rodriguez, E.; Hill, D.; Hill, J. C.; Hill, N.; Hiller, K. H.; Hillert, S.; Hillier, S. J.; Hinchliffe, I.; Hines, E.; Hirose, M.; Hirsch, F.; Hirschbuehl, D.; Hobbs, J.; Hod, N.; Hodgkinson, M. C.; Hodgson, P.; Hoecker, A.; Hoeferkamp, M. R.; Hoffman, J.; Hoffmann, D.; Hohlfeld, M.; Holder, M.; Holmes, A.; Holmgren, S. O.; Holy, T.; Holzbauer, J. L.; Homma, Y.; Hong, T. M.; Hooft van Huysduynen, L.; Horazdovsky, T.; Horn, C.; Horner, S.; Horton, K.; Hostachy, J.-Y.; Hou, S.; Houlden, M. A.; Hoummada, A.; Howarth, J.; Howell, D. F.; Hristova, I.; Hrivnac, J.; Hruska, I.; Hryn'Ova, T.; Hsu, P. J.; Hsu, S.-C.; Huang, G. S.; Hubacek, Z.; Hubaut, F.; Huegging, F.; Huffman, T. B.; Hughes, E. W.; Hughes, G.; Hughes-Jones, R. E.; Huhtinen, M.; Hurst, P.; Hurwitz, M.; Husemann, U.; Huseynov, N.; Huston, J.; Huth, J.; Iacobucci, G.; Iakovidis, G.; Ibbotson, M.; Ibragimov, I.; Ichimiya, R.; Iconomidou-Fayard, L.; Idarraga, J.; Idzik, M.; Iengo, P.; Igonkina, O.; Ikegami, Y.; Ikeno, M.; Ilchenko, Y.; Iliadis, D.; Imbault, D.; Imhaeuser, M.; Imori, M.; Ince, T.; Inigo-Golfin, J.; Ioannou, P.; Iodice, M.; Ionescu, G.; Irles Quiles, A.; Ishii, K.; Ishikawa, A.; Ishino, M.; Ishmukhametov, R.; Issever, C.; Istin, S.; Itoh, Y.; Ivashin, A. V.; Iwanski, W.; Iwasaki, H.; Izen, J. M.; Izzo, V.; Jackson, B.; Jackson, J. N.; Jackson, P.; Jaekel, M. R.; Jain, V.; Jakobs, K.; Jakobsen, S.; Jakubek, J.; Jana, D. K.; Jankowski, E.; Jansen, E.; Jantsch, A.; Janus, M.; Jarlskog, G.; Jeanty, L.; Jelen, K.; Jen-La Plante, I.; Jenni, P.; Jeremie, A.; Jež, P.; Jézéquel, S.; Jha, M. K.; Ji, H.; Ji, W.; Jia, J.; Jiang, Y.; Jimenez Belenguer, M.; Jin, G.; Jin, S.; Jinnouchi, O.; Joergensen, M. D.; Joffe, D.; Johansen, L. G.; Johansen, M.; Johansson, K. E.; Johansson, P.; Johnert, S.; Johns, K. A.; Jon-And, K.; Jones, G.; Jones, R. W. L.; Jones, T. W.; Jones, T. J.; Jonsson, O.; Joram, C.; Jorge, P. M.; Joseph, J.; Ju, X.; Juranek, V.; Jussel, P.; Kabachenko, V. V.; Kabana, S.; Kaci, M.; Kaczmarska, A.; Kadlecik, P.; Kado, M.; Kagan, H.; Kagan, M.; Kaiser, S.; Kajomovitz, E.; Kalinin, S.; Kalinovskaya, L. V.; Kama, S.; Kanaya, N.; Kaneda, M.; Kanno, T.; Kantserov, V. A.; Kanzaki, J.; Kaplan, B.; Kapliy, A.; Kaplon, J.; Kar, D.; Karagoz, M.; Karnevskiy, M.; Karr, K.; Kartvelishvili, V.; Karyukhin, A. N.; Kashif, L.; Kasmi, A.; Kass, R. D.; Kastanas, A.; Kataoka, M.; Kataoka, Y.; Katsoufis, E.; Katzy, J.; Kaushik, V.; Kawagoe, K.; Kawamoto, T.; Kawamura, G.; Kayl, M. S.; Kazanin, V. A.; Kazarinov, M. Y.; Keates, J. R.; Keeler, R.; Kehoe, R.; Keil, M.; Kekelidze, G. D.; Kelly, M.; Kennedy, J.; Kenney, C. J.; Kenyon, M.; Kepka, O.; Kerschen, N.; Kerševan, B. P.; Kersten, S.; Kessoku, K.; Ketterer, C.; Keung, J.; Khakzad, M.; Khalil-Zada, F.; Khandanyan, H.; Khanov, A.; Kharchenko, D.; Khodinov, A.; Kholodenko, A. G.; Khomich, A.; Khoo, T. J.; Khoriauli, G.; Khoroshilov, A.; Khovanskiy, N.; Khovanskiy, V.; Khramov, E.; Khubua, J.; Kim, H.; Kim, M. S.; Kim, P. C.; Kim, S. H.; Kimura, N.; Kind, O.; King, B. T.; King, M.; King, R. S. B.; Kirk, J.; Kirsch, G. P.; Kirsch, L. E.; Kiryunin, A. E.; Kisielewska, D.; Kittelmann, T.; Kiver, A. M.; Kiyamura, H.; Kladiva, E.; Klaiber-Lodewigs, J.; Klein, M.; Klein, U.; Kleinknecht, K.; Klemetti, M.; Klier, A.; Klimentov, A.; Klingenberg, R.; Klinkby, E. B.; Klioutchnikova, T.; Klok, P. F.; Klous, S.; Kluge, E.-E.; Kluge, T.; Kluit, P.; Kluth, S.; Kneringer, E.; Knobloch, J.; Knoops, E. B. F. G.; Knue, A.; Ko, B. R.; Kobayashi, T.; Kobel, M.; Koblitz, B.; Kocian, M.; Kocnar, A.; Kodys, P.; Köneke, K.; König, A. C.; Koenig, S.; Köpke, L.; Koetsveld, F.; Koevesarki, P.; Koffas, T.; Koffeman, E.; Kohn, F.; Kohout, Z.; Kohriki, T.; Koi, T.; Kokott, T.; Kolachev, G. M.; Kolanoski, H.; Kolesnikov, V.; Koletsou, I.; Koll, J.; Kollar, D.; Kollefrath, M.; Kolya, S. D.; Komar, A. A.; Komaragiri, J. R.; Kondo, T.; Kono, T.; Kononov, A. I.; Konoplich, R.; Konstantinidis, N.; Kootz, A.; Koperny, S.; Kopikov, S. V.; Korcyl, K.; Kordas, K.; Koreshev, V.; Korn, A.; Korol, A.; Korolkov, I.; Korolkova, E. V.; Korotkov, V. A.; Kortner, O.; Kortner, S.; Kostyukhin, V. V.; Kotamäki, M. J.; Kotov, S.; Kotov, V. M.; Kotwal, A.; Kourkoumelis, C.; Kouskoura, V.; Koutsman, A.; Kowalewski, R.; Kowalski, T. Z.; Kozanecki, W.; Kozhin, A. S.; Kral, V.; Kramarenko, V. A.; Kramberger, G.; Krasel, O.; Krasny, M. W.; Krasznahorkay, A.; Kraus, J.; Kreisel, A.; Krejci, F.; Kretzschmar, J.; Krieger, N.; Krieger, P.; Kroeninger, K.; Kroha, H.; Kroll, J.; Kroseberg, J.; Krstic, J.; Kruchonak, U.; Krüger, H.; Krumshteyn, Z. V.; Kruth, A.; Kubota, T.; Kuehn, S.; Kugel, A.; Kuhl, T.; Kuhn, D.; Kukhtin, V.; Kulchitsky, Y.; Kuleshov, S.; Kummer, C.; Kuna, M.; Kundu, N.; Kunkle, J.; Kupco, A.; Kurashige, H.; Kurata, M.; Kurochkin, Y. A.; Kus, V.; Kuykendall, W.; Kuze, M.; Kuzhir, P.; Kvasnicka, O.; Kvita, J.; Kwee, R.; La Rosa, A.; La Rotonda, L.; Labarga, L.; Labbe, J.; Lablak, S.; Lacasta, C.; Lacava, F.; Lacker, H.; Lacour, D.; Lacuesta, V. R.; Ladygin, E.; Lafaye, R.; Laforge, B.; Lagouri, T.; Lai, S.; Laisne, E.; Lamanna, M.; Lampen, C. L.; Lampl, W.; Lancon, E.; Landgraf, U.; Landon, M. P. J.; Landsman, H.; Lane, J. L.; Lange, C.; Lankford, A. J.; Lanni, F.; Lantzsch, K.; Lapin, V. V.; Laplace, S.; Lapoire, C.; Laporte, J. F.; Lari, T.; Larionov, A. V.; Larner, A.; Lasseur, C.; Lassnig, M.; Lau, W.; Laurelli, P.; Lavorato, A.; Lavrijsen, W.; Laycock, P.; Lazarev, A. B.; Lazzaro, A.; Le Dortz, O.; Le Guirriec, E.; Le Maner, C.; Le Menedeu, E.; Lebedev, A.; Lebel, C.; Lecompte, T.; Ledroit-Guillon, F.; Lee, H.; Lee, J. S. H.; Lee, S. C.; Lee, L.; Lefebvre, M.; Legendre, M.; Leger, A.; Legeyt, B. C.; Legger, F.; Leggett, C.; Lehmacher, M.; Lehmann Miotto, G.; Lei, X.; Leite, M. A. L.; Leitner, R.; Lellouch, D.; Lellouch, J.; Leltchouk, M.; Lendermann, V.; Leney, K. J. C.; Lenz, T.; Lenzen, G.; Lenzi, B.; Leonhardt, K.; Leontsinis, S.; Leroy, C.; Lessard, J.-R.; Lesser, J.; Lester, C. G.; Leung Fook Cheong, A.; Levêque, J.; Levin, D.; Levinson, L. J.; Levitski, M. S.; Lewandowska, M.; Lewis, A.; Lewis, G. H.; Leyko, A. M.; Leyton, M.; Li, B.; Li, H.; Li, S.; Li, X.; Liang, Z.; Liang, Z.; Liberti, B.; Lichard, P.; Lichtnecker, M.; Lie, K.; Liebig, W.; Lifshitz, R.; Lilley, J. N.; Limbach, C.; Limosani, A.; Limper, M.; Lin, S. C.; Linde, F.; Linnemann, J. T.; Lipeles, E.; Lipinsky, L.; Lipniacka, A.; Liss, T. M.; Lissauer, D.; Lister, A.; Litke, A. M.; Liu, C.; Liu, D.; Liu, H.; Liu, J. B.; Liu, M.; Liu, S.; Liu, Y.; Livan, M.; Livermore, S. S. A.; Lleres, A.; Llorente Merino, J.; Lloyd, S. L.; Lobodzinska, E.; Loch, P.; Lockman, W. S.; Lockwitz, S.; Loddenkoetter, T.; Loebinger, F. K.; Loginov, A.; Loh, C. W.; Lohse, T.; Lohwasser, K.; Lokajicek, M.; Loken, J.; Lombardo, V. P.; Long, R. E.; Lopes, L.; Lopez Mateos, D.; Losada, M.; Loscutoff, P.; Lo Sterzo, F.; Losty, M. J.; Lou, X.; Lounis, A.; Loureiro, K. F.; Love, J.; Love, P. A.; Lowe, A. J.; Lu, F.; Lu, L.; Lubatti, H. J.; Luci, C.; Lucotte, A.; Ludwig, A.; Ludwig, D.; Ludwig, I.; Ludwig, J.; Luehring, F.; Luijckx, G.; Lumb, D.; Luminari, L.; Lund, E.; Lund-Jensen, B.; Lundberg, B.; Lundberg, J.; Lundquist, J.; Lungwitz, M.; Lupi, A.; Lutz, G.; Lynn, D.; Lys, J.; Lytken, E.; Ma, H.; Ma, L. L.; Macana Goia, J. A.; Maccarrone, G.; Macchiolo, A.; Maček, B.; Machado Miguens, J.; Macina, D.; Mackeprang, R.; Madaras, R. J.; Mader, W. F.; Maenner, R.; Maeno, T.; Mättig, P.; Mättig, S.; Magalhaes Martins, P. J.; Magnoni, L.; Magradze, E.; Mahalalel, Y.; Mahboubi, K.; Mahout, G.; Maiani, C.; Maidantchik, C.; Maio, A.; Majewski, S.; Makida, Y.; Makovec, N.; Mal, P.; Malecki, Pa.; Malecki, P.; Maleev, V. P.; Malek, F.; Mallik, U.; Malon, D.; Maltezos, S.; Malyshev, V.; Malyukov, S.; Mameghani, R.; Mamuzic, J.; Manabe, A.; Mandelli, L.; Mandić, I.; Mandrysch, R.; Maneira, J.; Mangeard, P. S.; Manjavidze, I. D.; Mann, A.; Manning, P. M.; Manousakis-Katsikakis, A.; Mansoulie, B.; Manz, A.; Mapelli, A.; Mapelli, L.; March, L.; Marchand, J. F.; Marchese, F.; Marchiori, G.; Marcisovsky, M.; Marin, A.; Marino, C. P.; Marroquim, F.; Marshall, R.; Marshall, Z.; Martens, F. K.; Marti-Garcia, S.; Martin, A. J.; Martin, B.; Martin, B.; Martin, F. F.; Martin, J. P.; Martin, Ph.; Martin, T. A.; Martin Dit Latour, B.; Martinez, M.; Martinez Outschoorn, V.; Martyniuk, A. C.; Marx, M.; Marzano, F.; Marzin, A.; Masetti, L.; Mashimo, T.; Mashinistov, R.; Masik, J.; Maslennikov, A. L.; Maß, M.; Massa, I.; Massaro, G.; Massol, N.; Mastrandrea, P.; Mastroberardino, A.; Masubuchi, T.; Mathes, M.; Matricon, P.; Matsumoto, H.; Matsunaga, H.; Matsushita, T.; Mattravers, C.; Maugain, J. M.; Maxfield, S. J.; Maximov, D. A.; May, E. N.; Mayne, A.; Mazini, R.; Mazur, M.; Mazzanti, M.; Mazzoni, E.; Mc Kee, S. P.; McCarn, A.; McCarthy, R. L.; McCarthy, T. G.; McCubbin, N. A.; McFarlane, K. W.; McFayden, J. A.; McGlone, H.; McHedlidze, G.; McLaren, R. A.; McLaughlan, T.; McMahon, S. J.; McPherson, R. A.; Meade, A.; Mechnich, J.; Mechtel, M.; Medinnis, M.; Meera-Lebbai, R.; Meguro, T.; Mehdiyev, R.; Mehlhase, S.; Mehta, A.; Meier, K.; Meinhardt, J.; Meirose, B.; Melachrinos, C.; Mellado Garcia, B. R.; Mendoza Navas, L.; Meng, Z.; Mengarelli, A.; Menke, S.; Menot, C.; Meoni, E.; Mercurio, K. M.; Mermod, P.; Merola, L.; Meroni, C.; Merritt, F. S.; Messina, A.; Metcalfe, J.; Mete, A. S.; Meuser, S.; Meyer, C.; Meyer, J.-P.; Meyer, J.; Meyer, J.; Meyer, T. C.; Meyer, W. T.; Miao, J.; Michal, S.; Micu, L.; Middleton, R. P.; Miele, P.; Migas, S.; Mijović, L.; Mikenberg, G.; Mikestikova, M.; Mikuž, M.; Miller, D. W.; Miller, R. J.; Mills, W. J.; Mills, C.; Milov, A.; Milstead, D. A.; Milstein, D.; Minaenko, A. A.; Miñano, M.; Minashvili, I. A.; Mincer, A. I.; Mindur, B.; Mineev, M.; Ming, Y.; Mir, L. M.; Mirabelli, G.; Miralles Verge, L.; Misiejuk, A.; Mitrevski, J.; Mitrofanov, G. Y.; Mitsou, V. A.; Mitsui, S.; Miyagawa, P. S.; Miyazaki, K.; Mjörnmark, J. U.; Moa, T.; Mockett, P.; Moed, S.; Moeller, V.; Mönig, K.; Möser, N.; Mohapatra, S.; Mohn, B.; Mohr, W.; Mohrdieck-Möck, S.; Moisseev, A. M.; Moles-Valls, R.; Molina-Perez, J.; Monk, J.; Monnier, E.; Montesano, S.; Monticelli, F.; Monzani, S.; Moore, R. W.; Moorhead, G. F.; Mora Herrera, C.; Moraes, A.; Morais, A.; Morange, N.; Morello, G.; Moreno, D.; Moreno Llácer, M.; Morettini, P.; Morii, M.; Morin, J.; Morita, Y.; Morley, A. K.; Mornacchi, G.; Morone, M.-C.; Morozov, S. V.; Morris, J. D.; Moser, H. G.; Mosidze, M.; Moss, J.; Mount, R.; Mountricha, E.; Mouraviev, S. V.; Moyse, E. J. W.; Mudrinic, M.; Mueller, F.; Mueller, J.; Mueller, K.; Müller, T. A.; Muenstermann, D.; Muijs, A.; Muir, A.; Munwes, Y.; Murakami, K.; Murray, W. J.; Mussche, I.; Musto, E.; Myagkov, A. G.; Myska, M.; Nadal, J.; Nagai, K.; Nagano, K.; Nagasaka, Y.; Nairz, A. M.; Nakahama, Y.; Nakamura, K.; Nakano, I.; Nanava, G.; Napier, A.; Nash, M.; Nation, N. R.; Nattermann, T.; Naumann, T.; Navarro, G.; Neal, H. A.; Nebot, E.; Nechaeva, P. Yu.; Negri, A.; Negri, G.; Nektarijevic, S.; Nelson, A.; Nelson, S.; Nelson, T. K.; Nemecek, S.; Nemethy, P.; Nepomuceno, A. A.; Nessi, M.; Nesterov, S. Y.; Neubauer, M. S.; Neusiedl, A.; Neves, R. M.; Nevski, P.; Newman, P. R.; Nickerson, R. B.; Nicolaidou, R.; Nicolas, L.; Nicquevert, B.; Niedercorn, F.; Nielsen, J.; Niinikoski, T.; Nikiforov, A.; Nikolaenko, V.; Nikolaev, K.; Nikolic-Audit, I.; Nikolopoulos, K.; Nilsen, H.; Nilsson, P.; Ninomiya, Y.; Nisati, A.; Nishiyama, T.; Nisius, R.; Nodulman, L.; Nomachi, M.; Nomidis, I.; Nomoto, H.; Nordberg, M.; Nordkvist, B.; Norton, P. R.; Novakova, J.; Nozaki, M.; Nožička, M.; Nozka, L.; Nugent, I. M.; Nuncio-Quiroz, A.-E.; Nunes Hanninger, G.; Nunnemann, T.; Nurse, E.; Nyman, T.; O'Brien, B. J.; O'Neale, S. W.; O'Neil, D. C.; O'Shea, V.; Oakham, F. G.; Oberlack, H.; Ocariz, J.; Ochi, A.; Oda, S.; Odaka, S.; Odier, J.; Ogren, H.; Oh, A.; Oh, S. H.; Ohm, C. C.; Ohshima, T.; Ohshita, H.; Ohska, T. K.; Ohsugi, T.; Okada, S.; Okawa, H.; Okumura, Y.; Okuyama, T.; Olcese, M.; Olchevski, A. G.; Oliveira, M.; Oliveira Damazio, D.; Oliver Garcia, E.; Olivito, D.; Olszewski, A.; Olszowska, J.; Omachi, C.; Onofre, A.; Onyisi, P. U. E.; Oram, C. J.; Oreglia, M. J.; Oren, Y.; Orestano, D.; Orlov, I.; Oropeza Barrera, C.; Orr, R. S.; Ortega, E. O.; Osculati, B.; Ospanov, R.; Osuna, C.; Otero Y Garzon, G.; Ottersbach, J. P.; Ouchrif, M.; Ould-Saada, F.; Ouraou, A.; Ouyang, Q.; Owen, M.; Owen, S.; Øye, O. K.; Ozcan, V. E.; Ozturk, N.; Pacheco Pages, A.; Padilla Aranda, C.; Paganis, E.; Paige, F.; Pajchel, K.; Palestini, S.; Pallin, D.; Palma, A.; Palmer, J. D.; Pan, Y. B.; Panagiotopoulou, E.; Panes, B.; Panikashvili, N.; Panitkin, S.; Pantea, D.; Panuskova, M.; Paolone, V.; Papadelis, A.; Papadopoulou, Th. D.; Paramonov, A.; Park, W.; Parker, M. A.; Parodi, F.; Parsons, J. A.; Parzefall, U.; Pasqualucci, E.; Passeri, A.; Pastore, F.; Pastore, Fr.; Pásztor, G.; Pataraia, S.; Patel, N.; Pater, J. R.; Patricelli, S.; Pauly, T.; Pecsy, M.; Pedraza Morales, M. I.; Peleganchuk, S. V.; Peng, H.; Pengo, R.; Penson, A.; Penwell, J.; Perantoni, M.; Perez, K.; Perez Cavalcanti, T.; Perez Codina, E.; Pérez García-Estañ, M. T.; Perez Reale, V.; Peric, I.; Perini, L.; Pernegger, H.; Perrino, R.; Perrodo, P.; Persembe, S.; Peshekhonov, V. D.; Peters, O.; Petersen, B. A.; Petersen, J.; Petersen, T. C.; Petit, E.; Petridis, A.; Petridou, C.; Petrolo, E.; Petrucci, F.; Petschull, D.; Petteni, M.; Pezoa, R.; Phan, A.; Phillips, A. W.; Phillips, P. W.; Piacquadio, G.; Piccaro, E.; Piccinini, M.; Pickford, A.; Piec, S. M.; Piegaia, R.; Pilcher, J. E.; Pilkington, A. D.; Pina, J.; Pinamonti, M.; Pinder, A.; Pinfold, J. L.; Ping, J.; Pinto, B.; Pirotte, O.; Pizio, C.; Placakyte, R.; Plamondon, M.; Plano, W. G.; Pleier, M.-A.; Pleskach, A. V.; Poblaguev, A.; Poddar, S.; Podlyski, F.; Poggioli, L.; Poghosyan, T.; Pohl, M.; Polci, F.; Polesello, G.; Policicchio, A.; Polini, A.; Poll, J.; Polychronakos, V.; Pomarede, D. M.; Pomeroy, D.; Pommès, K.; Pontecorvo, L.; Pope, B. G.; Popeneciu, G. A.; Popovic, D. S.; Poppleton, A.; Portell Bueso, X.; Porter, R.; Posch, C.; Pospelov, G. E.; Pospisil, S.; Potrap, I. N.; Potter, C. J.; Potter, C. T.; Poulard, G.; Poveda, J.; Prabhu, R.; Pralavorio, P.; Pranko, A.; Prasad, S.; Pravahan, R.; Prell, S.; Pretzl, K.; Pribyl, L.; Price, D.; Price, L. E.; Price, M. J.; Prichard, P. M.; Prieur, D.; Primavera, M.; Prokofiev, K.; Prokoshin, F.; Protopopescu, S.; Proudfoot, J.; Prudent, X.; Przysiezniak, H.; Psoroulas, S.; Ptacek, E.; Purdham, J.; Purohit, M.; Puzo, P.; Pylypchenko, Y.; Qian, J.; Qian, Z.; Qin, Z.; Quadt, A.; Quarrie, D. R.; Quayle, W. B.; Quinonez, F.; Raas, M.; Radescu, V.; Radics, B.; Rador, T.; Ragusa, F.; Rahal, G.; Rahimi, A. M.; Rahm, D.; Rajagopalan, S.; Rammensee, M.; Rammes, M.; Ramstedt, M.; Randrianarivony, K.; Ratoff, P. N.; Rauscher, F.; Rauter, E.; Raymond, M.; Read, A. L.; Rebuzzi, D. M.; Redelbach, A.; Redlinger, G.; Reece, R.; Reeves, K.; Reichold, A.; Reinherz-Aronis, E.; Reinsch, A.; Reisinger, I.; Reljic, D.; Rembser, C.; Ren, Z. L.; Renaud, A.; Renkel, P.; Rensch, B.; Rescigno, M.; Resconi, S.; Resende, B.; Reznicek, P.; Rezvani, R.; Richards, A.; Richter, R.; Richter-Was, E.; Ridel, M.; Rieke, S.; Rijpstra, M.; Rijssenbeek, M.; Rimoldi, A.; Rinaldi, L.; Rios, R. R.; Riu, I.; Rivoltella, G.; Rizatdinova, F.; Rizvi, E.; Robertson, S. H.; Robichaud-Veronneau, A.; Robinson, D.; Robinson, J. E. M.; Robinson, M.; Robson, A.; Rocha de Lima, J. G.; Roda, C.; Roda Dos Santos, D.; Rodier, S.; Rodriguez, D.; Rodriguez Garcia, Y.; Roe, A.; Roe, S.; Røhne, O.; Rojo, V.; Rolli, S.; Romaniouk, A.; Romanov, V. M.; Romeo, G.; Romero Maltrana, D.; Roos, L.; Ros, E.; Rosati, S.; Rosbach, K.; Rose, M.; Rosenbaum, G. A.; Rosenberg, E. I.; Rosendahl, P. L.; Rosselet, L.; Rossetti, V.; Rossi, E.; Rossi, L. P.; Rossi, L.; Rotaru, M.; Roth, I.; Rothberg, J.; Rousseau, D.; Royon, C. R.; Rozanov, A.; Rozen, Y.; Ruan, X.; Rubinskiy, I.; Ruckert, B.; Ruckstuhl, N.; Rud, V. I.; Rudolph, G.; Rühr, F.; Ruggieri, F.; Ruiz-Martinez, A.; Rulikowska-Zarebska, E.; Rumiantsev, V.; Rumyantsev, L.; Runge, K.; Runolfsson, O.; Rurikova, Z.; Rusakovich, N. A.; Rust, D. R.; Rutherfoord, J. P.; Ruwiedel, C.; Ruzicka, P.; Ryabov, Y. F.; Ryadovikov, V.; Ryan, P.; Rybar, M.; Rybkin, G.; Ryder, N. C.; Rzaeva, S.; Saavedra, A. F.; Sadeh, I.; Sadrozinski, H. F.-W.; Sadykov, R.; Safai Tehrani, F.; Sakamoto, H.; Salamanna, G.; Salamon, A.; Saleem, M.; Salihagic, D.; Salnikov, A.; Salt, J.; Salvachua Ferrando, B. M.; Salvatore, D.; Salvatore, F.; Salvucci, A.; Salzburger, A.; Sampsonidis, D.; Samset, B. H.; Sandaker, H.; Sander, H. G.; Sanders, M. P.; Sandhoff, M.; Sandhu, P.; Sandoval, T.; Sandstroem, R.; Sandvoss, S.; Sankey, D. P. C.; Sansoni, A.; Santamarina Rios, C.; Santoni, C.; Santonico, R.; Santos, H.; Saraiva, J. G.; Sarangi, T.; Sarkisyan-Grinbaum, E.; Sarri, F.; Sartisohn, G.; Sasaki, O.; Sasaki, T.; Sasao, N.; Satsounkevitch, I.; Sauvage, G.; Sauvan, J. B.; Savard, P.; Savinov, V.; Savu, D. O.; Savva, P.; Sawyer, L.; Saxon, D. H.; Says, L. P.; Sbarra, C.; Sbrizzi, A.; Scallon, O.; Scannicchio, D. A.; Schaarschmidt, J.; Schacht, P.; Schäfer, U.; Schaepe, S.; Schaetzel, S.; Schaffer, A. C.; Schaile, D.; Schamberger, R. D.; Schamov, A. G.; Scharf, V.; Schegelsky, V. A.; Scheirich, D.; Scherzer, M. I.; Schiavi, C.; Schieck, J.; Schioppa, M.; Schlenker, S.; Schlereth, J. L.; Schmidt, E.; Schmidt, M. P.; Schmieden, K.; Schmitt, C.; Schmitt, S.; Schmitz, M.; Schöning, A.; Schott, M.; Schouten, D.; Schovancova, J.; Schram, M.; Schroeder, C.; Schroer, N.; Schuh, S.; Schuler, G.; Schultes, J.; Schultz-Coulon, H.-C.; Schulz, H.; Schumacher, J. W.; Schumacher, M.; Schumm, B. A.; Schune, Ph.; Schwanenberger, C.; Schwartzman, A.; Schwemling, Ph.; Schwienhorst, R.; Schwierz, R.; Schwindling, J.; Scott, W. G.; Searcy, J.; Sedykh, E.; Segura, E.; Seidel, S. C.; Seiden, A.; Seifert, F.; Seixas, J. M.; Sekhniaidze, G.; Seliverstov, D. M.; Sellden, B.; Sellers, G.; Seman, M.; Semprini-Cesari, N.; Serfon, C.; Serin, L.; Seuster, R.; Severini, H.; Sevior, M. E.; Sfyrla, A.; Shabalina, E.; Shamim, M.; Shan, L. Y.; Shank, J. T.; Shao, Q. T.; Shapiro, M.; Shatalov, P. B.; Shaver, L.; Shaw, C.; Shaw, K.; Sherman, D.; Sherwood, P.; Shibata, A.; Shimizu, S.; Shimojima, M.; Shin, T.; Shmeleva, A.; Shochet, M. J.; Short, D.; Shupe, M. A.; Sicho, P.; Sidoti, A.; Siebel, A.; Siegert, F.; Siegrist, J.; Sijacki, Dj.; Silbert, O.; Silva, J.; Silver, Y.; Silverstein, D.; Silverstein, S. B.; Simak, V.; Simard, O.; Simic, Lj.; Simion, S.; Simmons, B.; Simonyan, M.; Sinervo, P.; Sinev, N. B.; Sipica, V.; Siragusa, G.; Sisakyan, A. N.; Sivoklokov, S. Yu.; Sjölin, J.; Sjursen, T. B.; Skinnari, L. A.; Skovpen, K.; Skubic, P.; Skvorodnev, N.; Slater, M.; Slavicek, T.; Sliwa, K.; Sloan, T. J.; Sloper, J.; Smakhtin, V.; Smirnov, S. Yu.; Smirnova, L. N.; Smirnova, O.; Smith, B. C.; Smith, D.; Smith, K. M.; Smizanska, M.; Smolek, K.; Snesarev, A. A.; Snow, S. W.; Snow, J.; Snuverink, J.; Snyder, S.; Soares, M.; Sobie, R.; Sodomka, J.; Soffer, A.; Solans, C. A.; Solar, M.; Solc, J.; Soldatov, E.; Soldevila, U.; Solfaroli Camillocci, E.; Solodkov, A. A.; Solovyanov, O. V.; Sondericker, J.; Soni, N.; Sopko, V.; Sopko, B.; Sorbi, M.; Sosebee, M.; Soukharev, A.; Spagnolo, S.; Spanò, F.; Spighi, R.; Spigo, G.; Spila, F.; Spiriti, E.; Spiwoks, R.; Spousta, M.; Spreitzer, T.; Spurlock, B.; St. Denis, R. D.; Stahl, T.; Stahlman, J.; Stamen, R.; Stanecka, E.; Stanek, R. W.; Stanescu, C.; Stapnes, S.; Starchenko, E. A.; Stark, J.; Staroba, P.; Starovoitov, P.; Staude, A.; Stavina, P.; Stavropoulos, G.; Steele, G.; Steinbach, P.; Steinberg, P.; Stekl, I.; Stelzer, B.; Stelzer, H. J.; Stelzer-Chilton, O.; Stenzel, H.; Stevenson, K.; Stewart, G. A.; Stillings, J. A.; Stockmanns, T.; Stockton, M. C.; Stoerig, K.; Stoicea, G.; Stonjek, S.; Strachota, P.; Stradling, A. R.; Straessner, A.; Strandberg, J.; Strandberg, S.; Strandlie, A.; Strang, M.; Strauss, E.; Strauss, M.; Strizenec, P.; Ströhmer, R.; Strom, D. M.; Strong, J. A.; Stroynowski, R.; Strube, J.; Stugu, B.; Stumer, I.; Stupak, J.; Sturm, P.; Soh, D. A.; Su, D.; Subramania, Hs.; Succurro, A.; Sugaya, Y.; Sugimoto, T.; Suhr, C.; Suita, K.; Suk, M.; Sulin, V. V.; Sultansoy, S.; Sumida, T.; Sun, X.; Sundermann, J. E.; Suruliz, K.; Sushkov, S.; Susinno, G.; Sutton, M. R.; Suzuki, Y.; Svatos, M.; Sviridov, Yu. M.; Swedish, S.; Sykora, I.; Sykora, T.; Szeless, B.; Sánchez, J.; Ta, D.; Tackmann, K.; Taffard, A.; Tafirout, R.; Taga, A.; Taiblum, N.; Takahashi, Y.; Takai, H.; Takashima, R.; Takeda, H.; Takeshita, T.; Talby, M.; Talyshev, A.; Tamsett, M. C.; Tanaka, J.; Tanaka, R.; Tanaka, S.; Tanaka, S.; Tanaka, Y.; Tani, K.; Tannoury, N.; Tappern, G. P.; Tapprogge, S.; Tardif, D.; Tarem, S.; Tarrade, F.; Tartarelli, G. F.; Tas, P.; Tasevsky, M.; Tassi, E.; Tatarkhanov, M.; Taylor, C.; Taylor, F. E.; Taylor, G. N.; Taylor, W.; Teixeira Dias Castanheira, M.; Teixeira-Dias, P.; Temming, K. K.; Ten Kate, H.; Teng, P. K.; Terada, S.; Terashi, K.; Terron, J.; Terwort, M.; Testa, M.; Teuscher, R. J.; Thadome, J.; Therhaag, J.; Theveneaux-Pelzer, T.; Thioye, M.; Thoma, S.; Thomas, J. P.; Thompson, E. N.; Thompson, P. D.; Thompson, P. D.; Thompson, A. S.; Thomson, E.; Thomson, M.; Thun, R. P.; Tic, T.; Tikhomirov, V. O.; Tikhonov, Y. A.; Timmermans, C. J. W. P.; Tipton, P.; Tique Aires Viegas, F. J.; Tisserant, S.; Tobias, J.; Toczek, B.; Todorov, T.; Todorova-Nova, S.; Toggerson, B.; Tojo, J.; Tokár, S.; Tokunaga, K.; Tokushuku, K.; Tollefson, K.; Tomoto, M.; Tompkins, L.; Toms, K.; Tong, G.; Tonoyan, A.; Topfel, C.; Topilin, N. D.; Torchiani, I.; Torrence, E.; Torró Pastor, E.; Toth, J.; Touchard, F.; Tovey, D. R.; Traynor, D.; Trefzger, T.; Treis, J.; Tremblet, L.; Tricoli, A.; Trigger, I. M.; Trincaz-Duvoid, S.; Trinh, T. N.; Tripiana, M. F.; Triplett, N.; Trischuk, W.; Trivedi, A.; Trocmé, B.; Troncon, C.; Trottier-McDonald, M.; Trzupek, A.; Tsarouchas, C.; Tseng, J. C.-L.; Tsiakiris, M.; Tsiareshka, P. V.; Tsionou, D.; Tsipolitis, G.; Tsiskaridze, V.; Tskhadadze, E. G.; Tsukerman, I. I.; Tsulaia, V.; Tsung, J.-W.; Tsuno, S.; Tsybychev, D.; Tua, A.; Tuggle, J. M.; Turala, M.; Turecek, D.; Turk Cakir, I.; Turlay, E.; Turra, R.; Tuts, P. M.; Tykhonov, A.; Tylmad, M.; Tyndel, M.; Tyrvainen, H.; Tzanakos, G.; Uchida, K.; Ueda, I.; Ueno, R.; Ugland, M.; Uhlenbrock, M.; Uhrmacher, M.; Ukegawa, F.; Unal, G.; Underwood, D. G.; Undrus, A.; Unel, G.; Unno, Y.; Urbaniec, D.; Urkovsky, E.; Urrejola, P.; Usai, G.; Uslenghi, M.; Vacavant, L.; Vacek, V.; Vachon, B.; Vahsen, S.; Valenta, J.; Valente, P.; Valentinetti, S.; Valkar, S.; Valladolid Gallego, E.; Vallecorsa, S.; Valls Ferrer, J. A.; van der Graaf, H.; van der Kraaij, E.; van der Leeuw, R.; van der Poel, E.; van der Ster, D.; van Eijk, B.; van Eldik, N.; van Gemmeren, P.; van Kesteren, Z.; van Vulpen, I.; Vandelli, W.; Vandoni, G.; Vaniachine, A.; Vankov, P.; Vannucci, F.; Varela Rodriguez, F.; Vari, R.; Varnes, E. W.; Varouchas, D.; Vartapetian, A.; Varvell, K. E.; Vassilakopoulos, V. I.; Vazeille, F.; Vegni, G.; Veillet, J. J.; Vellidis, C.; Veloso, F.; Veness, R.; Veneziano, S.; Ventura, A.; Ventura, D.; Venturi, M.; Venturi, N.; Vercesi, V.; Verducci, M.; Verkerke, W.; Vermeulen, J. C.; Vest, A.; Vetterli, M. C.; Vichou, I.; Vickey, T.; Viehhauser, G. H. A.; Viel, S.; Villa, M.; Villaplana Perez, M.; Vilucchi, E.; Vincter, M. G.; Vinek, E.; Vinogradov, V. B.; Virchaux, M.; Viret, S.; Virzi, J.; Vitale, A.; Vitells, O.; Viti, M.; Vivarelli, I.; Vives Vaque, F.; Vlachos, S.; Vlasak, M.; Vlasov, N.; Vogel, A.; Vokac, P.; Volpi, G.; Volpi, M.; Volpini, G.; von der Schmitt, H.; von Loeben, J.; von Radziewski, H.; von Toerne, E.; Vorobel, V.; Vorobiev, A. P.; Vorwerk, V.; Vos, M.; Voss, R.; Voss, T. T.; Vossebeld, J. H.; Vranjes, N.; Vranjes Milosavljevic, M.; Vrba, V.; Vreeswijk, M.; Vu Anh, T.; Vuillermet, R.; Vukotic, I.; Wagner, W.; Wagner, P.; Wahlen, H.; Wakabayashi, J.; Walbersloh, J.; Walch, S.; Walder, J.; Walker, R.; Walkowiak, W.; Wall, R.; Waller, P.; Wang, C.; Wang, H.; Wang, H.; Wang, J.; Wang, J.; Wang, J. C.; Wang, R.; Wang, S. M.; Warburton, A.; Ward, C. P.; Warsinsky, M.; Watkins, P. M.; Watson, A. T.; Watson, M. F.; Watts, G.; Watts, S.; Waugh, A. T.; Waugh, B. M.; Weber, J.; Weber, M.; Weber, M. S.; Weber, P.; Weidberg, A. R.; Weigell, P.; Weingarten, J.; Weiser, C.; Wellenstein, H.; Wells, P. S.; Wen, M.; Wenaus, T.; Wendler, S.; Weng, Z.; Wengler, T.; Wenig, S.; Wermes, N.; Werner, M.; Werner, P.; Werth, M.; Wessels, M.; Weydert, C.; Whalen, K.; Wheeler-Ellis, S. J.; Whitaker, S. P.; White, A.; White, M. J.; White, S.; Whitehead, S. R.; Whiteson, D.; Whittington, D.; Wicek, F.; Wicke, D.; Wickens, F. J.; Wiedenmann, W.; Wielers, M.; Wienemann, P.; Wiik, L. A. M.; Wijeratne, P. A.; Wildauer, A.; Wildt, M. A.; Wilhelm, I.; Wilkens, H. G.; Will, J. Z.; Williams, E.; Williams, H. H.; Willis, W.; Willocq, S.; Wilson, J. A.; Wilson, M. G.; Wilson, A.; Wingerter-Seez, I.; Winkelmann, S.; Winklmeier, F.; Wittgen, M.; Wolter, M. W.; Wolters, H.; Wooden, G.; Wosiek, B. K.; Wotschack, J.; Woudstra, M. J.; Wraight, K.; Wright, C.; Wrona, B.; Wu, S. L.; Wu, X.; Wu, Y.; Wulf, E.; Wunstorf, R.; Wynne, B. M.; Xaplanteris, L.; Xella, S.; Xie, S.; Xie, Y.; Xu, C.; Xu, D.; Xu, G.; Yabsley, B.; Yamada, M.; Yamamoto, A.; Yamamoto, K.; Yamamoto, S.; Yamamura, T.; Yamaoka, J.; Yamazaki, T.; Yamazaki, Y.; Yan, Z.; Yang, H.; Yang, U. K.; Yang, Y.; Yang, Y.; Yang, Z.; Yanush, S.; Yao, W.-M.; Yao, Y.; Yasu, Y.; Ybeles Smit, G. V.; Ye, J.; Ye, S.; Yilmaz, M.; Yoosoofmiya, R.; Yorita, K.; Yoshida, R.; Young, C.; Youssef, S.; Yu, D.; Yu, J.; Yu, J.; Yuan, L.; Yurkewicz, A.; Zaets, V. G.; Zaidan, R.; Zaitsev, A. M.; Zajacova, Z.; Zalite, Yo. K.; Zanello, L.; Zarzhitsky, P.; Zaytsev, A.; Zeitnitz, C.; Zeller, M.; Zemla, A.; Zendler, C.; Zenin, A. V.; Zenin, O.; Ženiš, T.; Zenonos, Z.; Zenz, S.; Zerwas, D.; Zevi Della Porta, G.; Zhan, Z.; Zhang, D.; Zhang, H.; Zhang, J.; Zhang, X.; Zhang, Z.; Zhao, L.; Zhao, T.; Zhao, Z.; Zhemchugov, A.; Zheng, S.; Zhong, J.; Zhou, B.; Zhou, N.; Zhou, Y.; Zhu, C. G.; Zhu, H.; Zhu, Y.; Zhuang, X.; Zhuravlov, V.; Zieminska, D.; Zimmermann, R.; Zimmermann, S.; Zimmermann, S.; Ziolkowski, M.; Zitoun, R.; Živković, L.; Zmouchko, V. V.; Zobernig, G.; Zoccoli, A.; Zolnierowski, Y.; Zsenei, A.; Zur Nedden, M.; Zutshi, V.; Zwalinski, L.

2011-07-01

This Letter presents a measurement of the W+W- production cross section in s=7TeV pp collisions by the ATLAS experiment, using 34pb-1 of integrated luminosity produced by the Large Hadron Collider at CERN. Selecting events with two isolated leptons, each either an electron or a muon, 8 candidate events are observed with an expected background of 1.7±0.6 events. The measured cross section is 41-16+20(stat)±5(syst)±1(lumi)pb, which is consistent with the standard model prediction of 44±3pb calculated at next-to-leading order in QCD.

Applying physical science techniques and CERN technology to an unsolved problem in radiation treatment for cancer: the multidisciplinary 'VoxTox' research programme.

PubMed

Burnet, Neil G; Scaife, Jessica E; Romanchikova, Marina; Thomas, Simon J; Bates, Amy M; Wong, Emma; Noble, David J; Shelley, Leila Ea; Bond, Simon J; Forman, Julia R; Hoole, Andrew Cf; Barnett, Gillian C; Brochu, Frederic M; Simmons, Michael Pd; Jena, Raj; Harrison, Karl; Yeap, Ping Lin; Drew, Amelia; Silvester, Emma; Elwood, Patrick; Pullen, Hannah; Sultana, Andrew; Seah, Shannon Yk; Wilson, Megan Z; Russell, Simon G; Benson, Richard J; Rimmer, Yvonne L; Jefferies, Sarah J; Taku, Nicolette; Gurnell, Mark; Powlson, Andrew S; Schönlieb, Carola-Bibiane; Cai, Xiaohao; Sutcliffe, Michael Pf; Parker, Michael A

2017-06-01

The VoxTox research programme has applied expertise from the physical sciences to the problem of radiotherapy toxicity, bringing together expertise from engineering, mathematics, high energy physics (including the Large Hadron Collider), medical physics and radiation oncology. In our initial cohort of 109 men treated with curative radiotherapy for prostate cancer, daily image guidance computed tomography (CT) scans have been used to calculate delivered dose to the rectum, as distinct from planned dose, using an automated approach. Clinical toxicity data have been collected, allowing us to address the hypothesis that delivered dose provides a better predictor of toxicity than planned dose.

Efficiency Versus Instability in Plasma Accelerators

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lebedev, Valeri; Burov, Alexey; Nagaitsev, Sergei

2017-01-05

Plasma wake-field acceleration in a strongly nonlinear (a.k.a. the blowout) regime is one of the main candidates for future high-energy colliders. For this case, we derive a universal efficiency-instability relation, between the power efficiency and the key instability parameter of the witness bunch. We also show that in order to stabilize the witness bunch in a regime with high power efficiency, the bunch needs to have high energy spread, which is not presently compatible with collider-quality beam properties. It is unclear how such limitations could be overcome for high-luminosity linear colliders.

High Energy Physics Research with the CMS Experiment at CERN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Hanson, Gail G.

2013-05-31

The highlight of our last budget period, June 1, 2010, to May 31, 2013, was the discovery of the Higgs boson by the ATLAS and CMS experiments at the CERN Large Hadron Collider (LHC), announced on July 4, 2012, and for which François Englert and Peter Higgs were awarded the 2013 Nobel Prize in Physics on October 8, 2013. The Higgs boson was postulated in 1964 to explain how elementary particles obtain mass and was the missing piece of the Standard Model. However, the Standard Model does not describe everything that we know. There are many unanswered questions, such asmore » how can the Higgs boson have the mass that we have observed, are there more Higgs bosons, why is there more matter than antimatter, and what is the invisible dark matter, which constitutes about 85% of the matter in the universe. Our group played a significant role in the discovery of the Higgs boson and in subsequent analyses. We also carried out searches for new physics, in ways that could help elucidate some of the remaining questions. Our role in the CMS detector focused on the Tracker, a silicon strip outer tracker and pixel inner tracker.« less

Upgrade of the beam extraction system of the GTS-LHC electron cyclotron resonance ion source at CERN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Toivanen, V., E-mail: ville.aleksi.toivanen@cern.ch; Bellodi, G.; Dimov, V.

2016-02-15

Linac3 is the first accelerator in the heavy ion injector chain of the Large Hadron Collider (LHC), providing multiply charged heavy ion beams for the CERN experimental program. The ion beams are produced with GTS-LHC, a 14.5 GHz electron cyclotron resonance ion source, operated in afterglow mode. Improvement of the GTS-LHC beam formation and beam transport along Linac3 is part of the upgrade program of the injector chain in preparation for the future high luminosity LHC. A mismatch between the ion beam properties in the ion source extraction region and the acceptance of the following Low Energy Beam Transport (LEBT)more » section has been identified as one of the factors limiting the Linac3 performance. The installation of a new focusing element, an einzel lens, into the GTS-LHC extraction region is foreseen as a part of the Linac3 upgrade, as well as a redesign of the first section of the LEBT. Details of the upgrade and results of a beam dynamics study of the extraction region and LEBT modifications will be presented.« less

Detectors for Linear Colliders: Calorimetry at a Future Electron-Positron Collider (3/4)

ScienceCinema

Thomson, Mark

2018-04-16

Calorimetry will play a central role in determining the physics reach at a future e+e- collider. The requirements for calorimetry place the emphasis on achieving an excellent jet energy resolution. The currently favoured option for calorimetry at a future e+e- collider is the concept of high granularity particle flow calorimetry. Here granularity and a high pattern recognition capability is more important than the single particle calorimetric response. In this lecture I will describe the recent progress in understanding the reach of high granularity particle flow calorimetry and the related R&D; efforts which concentrate on test beam demonstrations of the technological options for highly granular calorimeters. I will also discuss alternatives to particle flow, for example the technique of dual readout calorimetry.

CP-violating top quark couplings at future linear e^+e^- colliders

NASA Astrophysics Data System (ADS)

Bernreuther, W.; Chen, L.; García, I.; Perelló, M.; Poeschl, R.; Richard, F.; Ros, E.; Vos, M.

2018-02-01

We study the potential of future lepton colliders to probe violation of the CP symmetry in the top quark sector. In certain extensions of the Standard Model, such as the two-Higgs-doublet model (2HDM), sizeable anomalous top quark dipole moments can arise, which may be revealed by a precise measurement of top quark pair production. We present results from detailed Monte Carlo studies for the ILC at 500 GeV and CLIC at 380 GeV and use parton-level simulations to explore the potential of high-energy operation. We find that precise measurements in e^+e^- → t\\bar{t} production with subsequent decay to lepton plus jets final states can provide sufficient sensitivity to detect Higgs-boson-induced CP violation in a viable two-Higgs-doublet model. The potential of a linear e^+e^- collider to detect CP-violating electric and weak dipole form factors of the top quark exceeds the prospects of the HL-LHC by over an order of magnitude.

Minimal supersymmetric B - L extension of the standard model, heavy H and light h Higgs boson production and decay at future e + e - linear colliders

NASA Astrophysics Data System (ADS)

Ramírez-Sánchez, F.; Gutierrez-Rodríguez, A.; Hernández-Ruiz, M. A.

2017-10-01

We study the phenomenology of the light h and heavy H Higgs boson production and decay in the context of a U(1) B - L extension of the standard model with an additional Z´ boson at future e + e - linear colliders with center-of-mass energies of √𝑠 = 500 - 3000 GeV and integrated luminosities of L = 500 - 2000 fb-1. The study includes the processes e + e - → (Z, Z´) → Zh and e + e - → (Z, Z´) → ZH, considering both the resonant and non-resonant effects. We find that the total number of expected Zh and ZH events can reach 106 and 105, respectively, which is a very optimistic scenario allowing us to perform precision measurements for both Higgs bosons h and H, as well as for the Z‧ boson in future high-energy and high-luminosity e + e - colliders.

Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in p p and p +Pb collisions with the ATLAS detector at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aaboud, M.; Aad, G.; Abbott, B.

A detailed study of multiparticle azimuthal correlations is presented using pp data at √s = 5.02 and 13 TeV, and p+Pb data at √ sNN = 5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants c n {4} and flow coefficients v n {4} = (-c n{4}) 1/4 for n = 2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of c n {4} are obtained as a function of the average number of charged particles permore » event, (N ch), using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to c n {4}. The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c 2 {4}, and therefore a well-defined v 2 {4}, nearly independent of (N ch), which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v 2 {4} is found to be smaller than the v 2 {2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v 2 {4} and v 2 {2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. The results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.« less

Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in p p and p +Pb collisions with the ATLAS detector at the CERN Large Hadron Collider

DOE Office of Scientific and Technical Information (OSTI.GOV)

Aaboud, M.; Aad, G.; Abbott, B.

A demore » tailed study of multiparticle azimuthal correlations is presented using pp data at $$\\sqrt{s}$$=5.02 and 13 TeV, and p+Pb data at s NN =5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants c n{4} and flow coefficients v n{4}=(-c n{4}) 1/4 for n=2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of c n{4} are obtained as a function of the average number of charged particles per event, N ch, using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to cn{4}. The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c 2{4}, and therefore a well-defined v 2{4}, nearly independent of N ch, which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v 2{4} is found to be smaller than the v 2{2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v 2{4} and v 2{2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. Finally, the results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.« less

Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in p p and p +Pb collisions with the ATLAS detector at the CERN Large Hadron Collider

DOE PAGES

Aaboud, M.; Aad, G.; Abbott, B.; ...

2018-02-12

A demore » tailed study of multiparticle azimuthal correlations is presented using pp data at $$\\sqrt{s}$$=5.02 and 13 TeV, and p+Pb data at s NN =5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants c n{4} and flow coefficients v n{4}=(-c n{4}) 1/4 for n=2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of c n{4} are obtained as a function of the average number of charged particles per event, N ch, using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to cn{4}. The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c 2{4}, and therefore a well-defined v 2{4}, nearly independent of N ch, which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v 2{4} is found to be smaller than the v 2{2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v 2{4} and v 2{2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. Finally, the results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.« less

Analysis of 440 GeV proton beam-matter interaction experiments at the High Radiation Materials test facility at CERN

NASA Astrophysics Data System (ADS)

Burkart, F.; Schmidt, R.; Raginel, V.; Wollmann, D.; Tahir, N. A.; Shutov, A.; Piriz, A. R.

2015-08-01

In a previous paper [Schmidt et al., Phys. Plasmas 21, 080701 (2014)], we presented the first results on beam-matter interaction experiments that were carried out at the High Radiation Materials test facility at CERN. In these experiments, extended cylindrical targets of solid copper were irradiated with beam of 440 GeV protons delivered by the Super Proton Synchrotron (SPS). The beam comprised of a large number of high intensity proton bunches, each bunch having a length of 0.5 ns with a 50 ns gap between two neighboring bunches, while the length of this entire bunch train was about 7 μs. These experiments established the existence of the hydrodynamic tunneling phenomenon the first time. Detailed numerical simulations of these experiments were also carried out which were reported in detail in another paper [Tahir et al., Phys. Rev. E 90, 063112 (2014)]. Excellent agreement was found between the experimental measurements and the simulation results that validate our previous simulations done using the Large Hadron Collider (LHC) beam of 7 TeV protons [Tahir et al., Phys. Rev. Spec. Top.--Accel. Beams 15, 051003 (2012)]. According to these simulations, the range of the full LHC proton beam and the hadronic shower can be increased by more than an order of magnitude due to the hydrodynamic tunneling, compared to that of a single proton. This effect is of considerable importance for the design of machine protection system for hadron accelerators such as SPS, LHC, and Future Circular Collider. Recently, using metal cutting technology, the targets used in these experiments have been dissected into finer pieces for visual and microscopic inspection in order to establish the precise penetration depth of the protons and the corresponding hadronic shower. This, we believe will be helpful in studying the very important phenomenon of hydrodynamic tunneling in a more quantitative manner. The details of this experimental work together with a comparison with the numerical simulations are presented in this paper.

Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in p p and p +Pb collisions with the ATLAS detector at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

Aaboud, M.; Aad, G.; Abbott, B.; Abdinov, O.; Abeloos, B.; Abidi, S. H.; Abouzeid, O. S.; Abraham, N. L.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B. S.; Adachi, S.; Adamczyk, L.; Adelman, J.; Adersberger, M.; Adye, T.; Affolder, A. A.; Afik, Y.; Agatonovic-Jovin, T.; Agheorghiesei, C.; Aguilar-Saavedra, J. A.; Ahlen, S. P.; Ahmadov, F.; Aielli, G.; Akatsuka, S.; Akerstedt, H.; Åkesson, T. P. A.; Akilli, E.; Akimov, A. V.; Alberghi, G. L.; Albert, J.; Albicocco, P.; Alconada Verzini, M. J.; Alderweireldt, S. C.; Aleksa, M.; Aleksandrov, I. N.; Alexa, C.; Alexander, G.; Alexopoulos, T.; Alhroob, M.; Ali, B.; Aliev, M.; Alimonti, G.; Alison, J.; Alkire, S. P.; Allbrooke, B. M. M.; Allen, B. W.; Allport, P. P.; Aloisio, A.; Alonso, A.; Alonso, F.; Alpigiani, C.; Alshehri, A. A.; Alstaty, M. I.; Alvarez Gonzalez, B.; Álvarez Piqueras, D.; Alviggi, M. G.; Amadio, B. T.; Amaral Coutinho, Y.; Amelung, C.; Amidei, D.; Amor Dos Santos, S. P.; Amoroso, S.; Amundsen, G.; Anastopoulos, C.; Ancu, L. S.; Andari, N.; Andeen, T.; Anders, C. F.; Anders, J. K.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Angelidakis, S.; Angelozzi, I.; Angerami, A.; Anisenkov, A. V.; Anjos, N.; Annovi, A.; Antel, C.; Antonelli, M.; Antonov, A.; Antrim, D. J.; Anulli, F.; Aoki, M.; Aperio Bella, L.; Arabidze, G.; Arai, Y.; Araque, J. P.; Araujo Ferraz, V.; Arce, A. T. H.; Ardell, R. E.; Arduh, F. A.; Arguin, J.-F.; Argyropoulos, S.; Arik, M.; Armbruster, A. J.; Armitage, L. J.; Arnaez, O.; Arnold, H.; Arratia, M.; Arslan, O.; Artamonov, A.; Artoni, G.; Artz, S.; Asai, S.; Asbah, N.; Ashkenazi, A.; Asquith, L.; Assamagan, K.; Astalos, R.; Atkinson, M.; Atlay, N. B.; Augsten, K.; Avolio, G.; Axen, B.; Ayoub, M. K.; Azuelos, G.; Baas, A. E.; Baca, M. J.; Bachacou, H.; Bachas, K.; Backes, M.; Bagnaia, P.; Bahmani, M.; Bahrasemani, H.; Baines, J. T.; Bajic, M.; Baker, O. K.; Bakker, P. J.; Baldin, E. M.; Balek, P.; Balli, F.; Balunas, W. K.; Banas, E.; Bandyopadhyay, A.; Banerjee, Sw.; Bannoura, A. A. E.; Barak, L.; Barberio, E. L.; Barberis, D.; Barbero, M.; Barillari, T.; Barisits, M.-S.; Barkeloo, J. T.; Barklow, T.; Barlow, N.; Barnes, S. L.; Barnett, B. M.; Barnett, R. M.; Barnovska-Blenessy, Z.; Baroncelli, A.; Barone, G.; Barr, A. J.; Barranco Navarro, L.; Barreiro, F.; Barreiro Guimarães da Costa, J.; Bartoldus, R.; Barton, A. E.; Bartos, P.; Basalaev, A.; Bassalat, A.; Bates, R. L.; Batista, S. J.; Batley, J. R.; Battaglia, M.; Bauce, M.; Bauer, F.; Bawa, H. S.; Beacham, J. B.; Beattie, M. D.; Beau, T.; Beauchemin, P. H.; Bechtle, P.; Beck, H. P.; Beck, H. C.; Becker, K.; Becker, M.; Becot, C.; Beddall, A. J.; Beddall, A.; Bednyakov, V. A.; Bedognetti, M.; Bee, C. P.; Beermann, T. A.; Begalli, M.; Begel, M.; Behr, J. K.; Bell, A. S.; Bella, G.; Bellagamba, L.; Bellerive, A.; Bellomo, M.; Belotskiy, K.; Beltramello, O.; Belyaev, N. L.; Benary, O.; Benchekroun, D.; Bender, M.; Benekos, N.; Benhammou, Y.; Benhar Noccioli, E.; Benitez, J.; Benjamin, D. P.; Benoit, M.; Bensinger, J. R.; Bentvelsen, S.; Beresford, L.; Beretta, M.; Berge, D.; Bergeaas Kuutmann, E.; Berger, N.; Beringer, J.; Berlendis, S.; Bernard, N. R.; Bernardi, G.; Bernius, C.; Bernlochner, F. U.; Berry, T.; Berta, P.; Bertella, C.; Bertoli, G.; Bertram, I. A.; Bertsche, C.; Bertsche, D.; Besjes, G. J.; Bessidskaia Bylund, O.; Bessner, M.; Besson, N.; Bethani, A.; Bethke, S.; Betti, A.; Bevan, A. J.; Beyer, J.; Bianchi, R. M.; Biebel, O.; Biedermann, D.; Bielski, R.; Bierwagen, K.; Biesuz, N. V.; Biglietti, M.; Billoud, T. R. V.; Bilokon, H.; Bindi, M.; Bingul, A.; Bini, C.; Biondi, S.; Bisanz, T.; Bittrich, C.; Bjergaard, D. M.; Black, J. E.; Black, K. M.; Blair, R. E.; Blazek, T.; Bloch, I.; Blocker, C.; Blue, A.; Blumenschein, U.; Blunier, S.; Bobbink, G. J.; Bobrovnikov, V. S.; Bocchetta, S. 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M.; Cardarelli, R.; Cardillo, F.; Carli, I.; Carli, T.; Carlino, G.; Carlson, B. T.; Carminati, L.; Carney, R. M. D.; Caron, S.; Carquin, E.; Carrá, S.; Carrillo-Montoya, G. D.; Casadei, D.; Casado, M. P.; Casolino, M.; Casper, D. W.; Castelijn, R.; Castillo Gimenez, V.; Castro, N. F.; Catinaccio, A.; Catmore, J. R.; Cattai, A.; Caudron, J.; Cavaliere, V.; Cavallaro, E.; Cavalli, D.; Cavalli-Sforza, M.; Cavasinni, V.; Celebi, E.; Ceradini, F.; Cerda Alberich, L.; Cerqueira, A. S.; Cerri, A.; Cerrito, L.; Cerutti, F.; Cervelli, A.; Cetin, S. A.; Chafaq, A.; Chakraborty, D.; Chan, S. K.; Chan, W. S.; Chan, Y. L.; Chang, P.; Chapman, J. D.; Charlton, D. G.; Chau, C. C.; Chavez Barajas, C. A.; Che, S.; Cheatham, S.; Chegwidden, A.; Chekanov, S.; Chekulaev, S. V.; Chelkov, G. A.; Chelstowska, M. A.; Chen, C.; Chen, C.; Chen, H.; Chen, J.; Chen, S.; Chen, S.; Chen, X.; Chen, Y.; Cheng, H. C.; Cheng, H. J.; Cheplakov, A.; Cheremushkina, E.; Cherkaoui El Moursli, R.; Cheu, E.; Cheung, K.; Chevalier, L.; Chiarella, V.; Chiarelli, G.; Chiodini, G.; Chisholm, A. S.; Chitan, A.; Chiu, Y. H.; Chizhov, M. V.; Choi, K.; Chomont, A. R.; Chouridou, S.; Chow, Y. S.; Christodoulou, V.; Chu, M. C.; Chudoba, J.; Chuinard, A. J.; Chwastowski, J. J.; Chytka, L.; Ciftci, A. K.; Cinca, D.; Cindro, V.; Cioara, I. A.; Ciocio, A.; Cirotto, F.; Citron, Z. H.; Citterio, M.; Ciubancan, M.; Clark, A.; Clark, B. L.; Clark, M. R.; Clark, P. J.; Clarke, R. N.; Clement, C.; Coadou, Y.; Cobal, M.; Coccaro, A.; Cochran, J.; Colasurdo, L.; Cole, B.; Colijn, A. P.; Collot, J.; Colombo, T.; Conde Muiño, P.; Coniavitis, E.; Connell, S. H.; Connelly, I. A.; Constantinescu, S.; Conti, G.; Conventi, F.; Cooke, M.; Cooper-Sarkar, A. M.; Cormier, F.; Cormier, K. J. R.; Corradi, M.; Corriveau, F.; Cortes-Gonzalez, A.; Costa, G.; Costa, M. J.; Costanzo, D.; Cottin, G.; Cowan, G.; Cox, B. E.; Cranmer, K.; Crawley, S. 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V.; Dehghanian, N.; Deigaard, I.; Del Gaudio, M.; Del Peso, J.; Delgove, D.; Deliot, F.; Delitzsch, C. M.; Dell'Acqua, A.; Dell'Asta, L.; Dell'Orso, M.; Della Pietra, M.; Della Volpe, D.; Delmastro, M.; Delporte, C.; Delsart, P. A.; Demarco, D. A.; Demers, S.; Demichev, M.; Demilly, A.; Denisov, S. P.; Denysiuk, D.; Derendarz, D.; Derkaoui, J. E.; Derue, F.; Dervan, P.; Desch, K.; Deterre, C.; Dette, K.; Devesa, M. R.; Deviveiros, P. O.; Dewhurst, A.; Dhaliwal, S.; di Bello, F. A.; di Ciaccio, A.; di Ciaccio, L.; di Clemente, W. K.; di Donato, C.; di Girolamo, A.; di Girolamo, B.; di Micco, B.; di Nardo, R.; di Petrillo, K. F.; di Simone, A.; di Sipio, R.; di Valentino, D.; Diaconu, C.; Diamond, M.; Dias, F. A.; Diaz, M. A.; Diehl, E. B.; Dietrich, J.; Díez Cornell, S.; Dimitrievska, A.; Dingfelder, J.; Dita, P.; Dita, S.; Dittus, F.; Djama, F.; Djobava, T.; Djuvsland, J. I.; Do Vale, M. A. B.; Dobos, D.; Dobre, M.; Dodsworth, D.; Doglioni, C.; Dolejsi, J.; Dolezal, Z.; Donadelli, M.; Donati, S.; Dondero, P.; Donini, J.; Dopke, J.; Doria, A.; Dova, M. T.; Doyle, A. T.; Drechsler, E.; Dris, M.; Du, Y.; Duarte-Campderros, J.; Dubinin, F.; Dubreuil, A.; Duchovni, E.; Duckeck, G.; Ducourthial, A.; Ducu, O. A.; Duda, D.; Dudarev, A.; Dudder, A. Chr.; Duffield, E. M.; Duflot, L.; Dührssen, M.; Dulsen, C.; Dumancic, M.; Dumitriu, A. E.; Duncan, A. K.; Dunford, M.; Duperrin, A.; Duran Yildiz, H.; Düren, M.; Durglishvili, A.; Duschinger, D.; Dutta, B.; Duvnjak, D.; Dyndal, M.; Dziedzic, B. S.; Eckardt, C.; Ecker, K. M.; Edgar, R. C.; Eifert, T.; Eigen, G.; Einsweiler, K.; Ekelof, T.; El Kacimi, M.; El Kosseifi, R.; Ellajosyula, V.; Ellert, M.; Elles, S.; Ellinghaus, F.; Elliot, A. A.; Ellis, N.; Elmsheuser, J.; Elsing, M.; Emeliyanov, D.; Enari, Y.; Ennis, J. S.; Epland, M. B.; Erdmann, J.; Ereditato, A.; Ernst, M.; Errede, S.; Escalier, M.; Escobar, C.; Esposito, B.; Estrada Pastor, O.; Etienvre, A. I.; Etzion, E.; Evans, H.; Ezhilov, A.; Ezzi, M.; Fabbri, F.; Fabbri, L.; Fabiani, V.; Facini, G.; Fakhrutdinov, R. M.; Falciano, S.; Falla, R. J.; Faltova, J.; Fang, Y.; Fanti, M.; Farbin, A.; Farilla, A.; Farina, C.; Farina, E. M.; Farooque, T.; Farrell, S.; Farrington, S. M.; Farthouat, P.; Fassi, F.; Fassnacht, P.; Fassouliotis, D.; Faucci Giannelli, M.; Favareto, A.; Fawcett, W. J.; Fayard, L.; Fedin, O. L.; Fedorko, W.; Feigl, S.; Feligioni, L.; Feng, C.; Feng, E. J.; Fenton, M. J.; Fenyuk, A. B.; Feremenga, L.; Fernandez Martinez, P.; Ferrando, J.; Ferrari, A.; Ferrari, P.; Ferrari, R.; Ferreira de Lima, D. E.; Ferrer, A.; Ferrere, D.; Ferretti, C.; Fiedler, F.; Filipčič, A.; Filipuzzi, M.; Filthaut, F.; Fincke-Keeler, M.; Finelli, K. D.; Fiolhais, M. C. N.; Fiorini, L.; Fischer, A.; Fischer, C.; Fischer, J.; Fisher, W. C.; Flaschel, N.; Fleck, I.; Fleischmann, P.; Fletcher, R. R. M.; Flick, T.; Flierl, B. M.; Flores Castillo, L. R.; Flowerdew, M. J.; Forcolin, G. T.; Formica, A.; Förster, F. A.; Forti, A.; Foster, A. G.; Fournier, D.; Fox, H.; Fracchia, S.; Francavilla, P.; Franchini, M.; Franchino, S.; Francis, D.; Franconi, L.; Franklin, M.; Frate, M.; Fraternali, M.; Freeborn, D.; Fressard-Batraneanu, S. M.; Freund, B.; Froidevaux, D.; Frost, J. A.; Fukunaga, C.; Fusayasu, T.; Fuster, J.; Gabizon, O.; Gabrielli, A.; Gabrielli, A.; Gach, G. P.; Gadatsch, S.; Gadomski, S.; Gagliardi, G.; Gagnon, L. G.; Galea, C.; Galhardo, B.; Gallas, E. J.; Gallop, B. J.; Gallus, P.; Galster, G.; Gan, K. K.; Ganguly, S.; Gao, Y.; Gao, Y. S.; Garay Walls, F. M.; García, C.; García Navarro, J. E.; García Pascual, J. A.; Garcia-Sciveres, M.; Gardner, R. W.; Garelli, N.; Garonne, V.; Gascon Bravo, A.; Gasnikova, K.; Gatti, C.; Gaudiello, A.; Gaudio, G.; Gavrilenko, I. L.; Gay, C.; Gaycken, G.; Gazis, E. N.; Gee, C. N. P.; Geisen, J.; Geisen, M.; Geisler, M. P.; Gellerstedt, K.; Gemme, C.; Genest, M. H.; Geng, C.; Gentile, S.; Gentsos, C.; George, S.; Gerbaudo, D.; Geßner, G.; Ghasemi, S.; Ghneimat, M.; Giacobbe, B.; Giagu, S.; Giangiacomi, N.; Giannetti, P.; Gibson, S. M.; Gignac, M.; Gilchriese, M.; Gillberg, D.; Gilles, G.; Gingrich, D. M.; Giordani, M. P.; Giorgi, F. M.; Giraud, P. F.; Giromini, P.; Giugliarelli, G.; Giugni, D.; Giuli, F.; Giuliani, C.; Giulini, M.; Gjelsten, B. K.; Gkaitatzis, S.; Gkialas, I.; Gkougkousis, E. L.; Gkountoumis, P.; Gladilin, L. K.; Glasman, C.; Glatzer, J.; Glaysher, P. C. F.; Glazov, A.; Goblirsch-Kolb, M.; Godlewski, J.; Goldfarb, S.; Golling, T.; Golubkov, D.; Gomes, A.; Gonçalo, R.; Goncalves Gama, R.; Goncalves Pinto Firmino da Costa, J.; Gonella, G.; Gonella, L.; Gongadze, A.; Gonski, J. L.; González de La Hoz, S.; Gonzalez-Sevilla, S.; Goossens, L.; Gorbounov, P. A.; Gordon, H. A.; Gorelov, I.; Gorini, B.; Gorini, E.; Gorišek, A.; Goshaw, A. T.; Gössling, C.; Gostkin, M. I.; Gottardo, C. A.; Goudet, C. R.; Goujdami, D.; Goussiou, A. G.; Govender, N.; Gozani, E.; Grabowska-Bold, I.; Gradin, P. O. J.; Gramling, J.; Gramstad, E.; Grancagnolo, S.; Gratchev, V.; Gravila, P. M.; Gray, C.; Gray, H. M.; Greenwood, Z. D.; Grefe, C.; Gregersen, K.; Gregor, I. M.; Grenier, P.; Grevtsov, K.; Griffiths, J.; Grillo, A. A.; Grimm, K.; Grinstein, S.; Gris, Ph.; Grivaz, J.-F.; Groh, S.; Gross, E.; Grosse-Knetter, J.; Grossi, G. C.; Grout, Z. J.; Grummer, A.; Guan, L.; Guan, W.; Guenther, J.; Guescini, F.; Guest, D.; Gueta, O.; Gui, B.; Guido, E.; Guillemin, T.; Guindon, S.; Gul, U.; Gumpert, C.; Guo, J.; Guo, W.; Guo, Y.; Gupta, R.; Gurbuz, S.; Gustavino, G.; Gutelman, B. J.; Gutierrez, P.; Gutierrez Ortiz, N. G.; Gutschow, C.; Guyot, C.; Guzik, M. P.; Gwenlan, C.; Gwilliam, C. B.; Haas, A.; Haber, C.; Hadavand, H. K.; Haddad, N.; Hadef, A.; Hageböck, S.; Hagihara, M.; Hakobyan, H.; Haleem, M.; Haley, J.; Halladjian, G.; Hallewell, G. D.; Hamacher, K.; Hamal, P.; Hamano, K.; Hamilton, A.; Hamity, G. N.; Hamnett, P. G.; Han, L.; Han, S.; Hanagaki, K.; Hanawa, K.; Hance, M.; Handl, D. M.; Haney, B.; Hanke, P.; Hansen, J. B.; Hansen, J. D.; Hansen, M. C.; Hansen, P. H.; Hara, K.; Hard, A. S.; Harenberg, T.; Hariri, F.; Harkusha, S.; Harrison, P. F.; Hartmann, N. M.; Hasegawa, Y.; Hasib, A.; Hassani, S.; Haug, S.; Hauser, R.; Hauswald, L.; Havener, L. B.; Havranek, M.; Hawkes, C. M.; Hawkings, R. J.; Hayakawa, D.; Hayden, D.; Hays, C. P.; Hays, J. M.; Hayward, H. S.; Haywood, S. J.; Head, S. J.; Heck, T.; Hedberg, V.; Heelan, L.; Heer, S.; Heidegger, K. K.; Heim, S.; Heim, T.; Heinemann, B.; Heinrich, J. J.; Heinrich, L.; Heinz, C.; Hejbal, J.; Helary, L.; Held, A.; Hellman, S.; Helsens, C.; Henderson, R. C. W.; Heng, Y.; Henkelmann, S.; Henriques Correia, A. M.; Henrot-Versille, S.; Herbert, G. H.; Herde, H.; Herget, V.; Hernández Jiménez, Y.; Herr, H.; Herten, G.; Hertenberger, R.; Hervas, L.; Herwig, T. C.; Hesketh, G. G.; Hessey, N. P.; Hetherly, J. W.; Higashino, S.; Higón-Rodriguez, E.; Hildebrand, K.; Hill, E.; Hill, J. C.; Hiller, K. H.; Hillier, S. J.; Hils, M.; Hinchliffe, I.; Hirose, M.; Hirschbuehl, D.; Hiti, B.; Hladik, O.; Hlaluku, D. R.; Hoad, X.; Hobbs, J.; Hod, N.; Hodgkinson, M. C.; Hodgson, P.; Hoecker, A.; Hoeferkamp, M. R.; Hoenig, F.; Hohn, D.; Holmes, T. R.; Homann, M.; Honda, S.; Honda, T.; Hong, T. M.; Hooberman, B. H.; Hopkins, W. H.; Horii, Y.; Horton, A. J.; Hostachy, J.-Y.; Hostiuc, A.; Hou, S.; Hoummada, A.; Howarth, J.; Hoya, J.; Hrabovsky, M.; Hrdinka, J.; Hristova, I.; Hrivnac, J.; Hryn'ova, T.; Hrynevich, A.; Hsu, P. J.; Hsu, S.-C.; Hu, Q.; Hu, S.; Huang, Y.; Hubacek, Z.; Hubaut, F.; Huegging, F.; Huffman, T. B.; Hughes, E. W.; Huhtinen, M.; Hunter, R. F. H.; Huo, P.; Huseynov, N.; Huston, J.; Huth, J.; Hyneman, R.; Iacobucci, G.; Iakovidis, G.; Ibragimov, I.; Iconomidou-Fayard, L.; Idrissi, Z.; Iengo, P.; Igonkina, O.; Iizawa, T.; Ikegami, Y.; Ikeno, M.; Ilchenko, Y.; Iliadis, D.; Ilic, N.; Iltzsche, F.; Introzzi, G.; Ioannou, P.; Iodice, M.; Iordanidou, K.; Ippolito, V.; Isacson, M. F.; Ishijima, N.; Ishino, M.; Ishitsuka, M.; Issever, C.; Istin, S.; Ito, F.; Iturbe Ponce, J. M.; Iuppa, R.; Iwasaki, H.; Izen, J. M.; Izzo, V.; Jabbar, S.; Jackson, P.; Jacobs, R. M.; Jain, V.; Jakobi, K. B.; Jakobs, K.; Jakobsen, S.; Jakoubek, T.; Jamin, D. O.; Jana, D. K.; Jansky, R.; Janssen, J.; Janus, M.; Janus, P. A.; Jarlskog, G.; Javadov, N.; Javå¯Rek, T.; Javurkova, M.; Jeanneau, F.; Jeanty, L.; Jejelava, J.; Jelinskas, A.; Jenni, P.; Jeske, C.; Jézéquel, S.; Ji, H.; Jia, J.; Jiang, H.; Jiang, Y.; Jiang, Z.; Jiggins, S.; Jimenez Pena, J.; Jin, S.; Jinaru, A.; Jinnouchi, O.; Jivan, H.; Johansson, P.; Johns, K. A.; Johnson, C. A.; Johnson, W. J.; Jon-And, K.; Jones, R. W. L.; Jones, S. D.; Jones, S.; Jones, T. J.; Jongmanns, J.; Jorge, P. M.; Jovicevic, J.; Ju, X.; Juste Rozas, A.; Köhler, M. K.; Kaczmarska, A.; Kado, M.; Kagan, H.; Kagan, M.; Kahn, S. J.; Kaji, T.; Kajomovitz, E.; Kalderon, C. W.; Kaluza, A.; Kama, S.; Kamenshchikov, A.; Kanaya, N.; Kanjir, L.; Kantserov, V. A.; Kanzaki, J.; Kaplan, B.; Kaplan, L. S.; Kar, D.; Karakostas, K.; Karastathis, N.; Kareem, M. J.; Karentzos, E.; Karpov, S. N.; Karpova, Z. M.; Karthik, K.; Kartvelishvili, V.; Karyukhin, A. N.; Kasahara, K.; Kashif, L.; Kass, R. D.; Kastanas, A.; Kataoka, Y.; Kato, C.; Katre, A.; Katzy, J.; Kawade, K.; Kawagoe, K.; Kawamoto, T.; Kawamura, G.; Kay, E. F.; Kazanin, V. F.; Keeler, R.; Kehoe, R.; Keller, J. S.; Kellermann, E.; Kempster, J. J.; Kendrick, J.; Keoshkerian, H.; Kepka, O.; Kerševan, B. P.; Kersten, S.; Keyes, R. A.; Khader, M.; Khalil-Zada, F.; Khanov, A.; Kharlamov, A. G.; Kharlamova, T.; Khodinov, A.; Khoo, T. J.; Khovanskiy, V.; Khramov, E.; Khubua, J.; Kido, S.; Kilby, C. R.; Kim, H. Y.; Kim, S. H.; Kim, Y. K.; Kimura, N.; Kind, O. M.; King, B. T.; Kirchmeier, D.; Kirk, J.; Kiryunin, A. E.; Kishimoto, T.; Kisielewska, D.; Kitali, V.; Kivernyk, O.; Kladiva, E.; Klapdor-Kleingrothaus, T.; Klein, M. H.; Klein, M.; Klein, U.; Kleinknecht, K.; Klimek, P.; Klimentov, A.; Klingenberg, R.; Klingl, T.; Klioutchnikova, T.; Klitzner, F. F.; Kluge, E.-E.; Kluit, P.; Kluth, S.; Kneringer, E.; Knoops, E. B. F. G.; Knue, A.; Kobayashi, A.; Kobayashi, D.; Kobayashi, T.; Kobel, M.; Kocian, M.; Kodys, P.; Koffas, T.; Koffeman, E.; Köhler, N. M.; Koi, T.; Kolb, M.; Koletsou, I.; Komar, A. A.; Kondo, T.; Kondrashova, N.; Köneke, K.; König, A. C.; Kono, T.; Konoplich, R.; Konstantinidis, N.; Konya, B.; Kopeliansky, R.; Koperny, S.; Kopp, A. K.; Korcyl, K.; Kordas, K.; Korn, A.; Korol, A. A.; Korolkov, I.; Korolkova, E. V.; Kortner, O.; Kortner, S.; Kosek, T.; Kostyukhin, V. V.; Kotwal, A.; Koulouris, A.; Kourkoumeli-Charalampidi, A.; Kourkoumelis, C.; Kourlitis, E.; Kouskoura, V.; Kowalewska, A. B.; Kowalewski, R.; Kowalski, T. Z.; Kozakai, C.; Kozanecki, W.; Kozhin, A. S.; Kramarenko, V. A.; Kramberger, G.; Krasnopevtsev, D.; Krasny, M. W.; Krasznahorkay, A.; Krauss, D.; Kremer, J. A.; Kretzschmar, J.; Kreutzfeldt, K.; Krieger, P.; Krizka, K.; Kroeninger, K.; Kroha, H.; Kroll, J.; Kroll, J.; Kroseberg, J.; Krstic, J.; Kruchonak, U.; Krüger, H.; Krumnack, N.; Kruse, M. C.; Kubota, T.; Kucuk, H.; Kuday, S.; Kuechler, J. T.; Kuehn, S.; Kugel, A.; Kuger, F.; Kuhl, T.; Kukhtin, V.; Kukla, R.; Kulchitsky, Y.; Kuleshov, S.; Kulinich, Y. P.; Kuna, M.; Kunigo, T.; Kupco, A.; Kupfer, T.; Kuprash, O.; Kurashige, H.; Kurchaninov, L. L.; Kurochkin, Y. A.; Kurth, M. G.; Kuwertz, E. S.; Kuze, M.; Kvita, J.; Kwan, T.; Kyriazopoulos, D.; La Rosa, A.; La Rosa Navarro, J. L.; La Rotonda, L.; La Ruffa, F.; Lacasta, C.; Lacava, F.; Lacey, J.; Lack, D. P. J.; Lacker, H.; Lacour, D.; Ladygin, E.; Lafaye, R.; Laforge, B.; Lagouri, T.; Lai, S.; Lammers, S.; Lampl, W.; Lançon, E.; Landgraf, U.; Landon, M. P. J.; Lanfermann, M. C.; Lang, V. S.; Lange, J. C.; Langenberg, R. J.; Lankford, A. J.; Lanni, F.; Lantzsch, K.; Lanza, A.; Lapertosa, A.; Laplace, S.; Laporte, J. F.; Lari, T.; Lasagni Manghi, F.; Lassnig, M.; Lau, T. S.; Laurelli, P.; Lavrijsen, W.; Law, A. T.; Laycock, P.; Lazovich, T.; Lazzaroni, M.; Le, B.; Le Dortz, O.; Le Guirriec, E.; Le Quilleuc, E. P.; Leblanc, M.; Lecompte, T.; Ledroit-Guillon, F.; Lee, C. A.; Lee, G. R.; Lee, S. C.; Lee, L.; Lefebvre, B.; Lefebvre, G.; Lefebvre, M.; Legger, F.; Leggett, C.; Lehmann Miotto, G.; Lei, X.; Leight, W. A.; Leite, M. A. L.; Leitner, R.; Lellouch, D.; Lemmer, B.; Leney, K. J. C.; Lenz, T.; Lenzi, B.; Leone, R.; Leone, S.; Leonidopoulos, C.; Lerner, G.; Leroy, C.; Les, R.; Lesage, A. A. J.; Lester, C. G.; Levchenko, M.; Levêque, J.; Levin, D.; Levinson, L. J.; Levy, M.; Lewis, D.; Li, B.; Li, Changqiao; Li, H.; Li, L.; Li, Q.; Li, Q.; Li, S.; Li, X.; Li, Y.; Liang, Z.; Liberti, B.; Liblong, A.; Lie, K.; Liebal, J.; Liebig, W.; Limosani, A.; Lin, K.; Lin, S. C.; Lin, T. H.; Linck, R. A.; Lindquist, B. E.; Lionti, A. E.; Lipeles, E.; Lipniacka, A.; Lisovyi, M.; Liss, T. M.; Lister, A.; Litke, A. M.; Liu, B.; Liu, H.; Liu, H.; Liu, J. K. K.; Liu, J.; Liu, J. B.; Liu, K.; Liu, L.; Liu, M.; Liu, Y. L.; Liu, Y.; Livan, M.; Lleres, A.; Llorente Merino, J.; Lloyd, S. L.; Lo, C. Y.; Lo Sterzo, F.; Lobodzinska, E. M.; Loch, P.; Loebinger, F. K.; Loesle, A.; Loew, K. M.; Lohse, T.; Lohwasser, K.; Lokajicek, M.; Long, B. A.; Long, J. D.; Long, R. E.; Longo, L.; Looper, K. A.; Lopez, J. A.; Lopez Paz, I.; Lopez Solis, A.; Lorenz, J.; Lorenzo Martinez, N.; Losada, M.; Lösel, P. J.; Lou, X.; Lounis, A.; Love, J.; Love, P. A.; Lu, H.; Lu, N.; Lu, Y. J.; Lubatti, H. J.; Luci, C.; Lucotte, A.; Luedtke, C.; Luehring, F.; Lukas, W.; Luminari, L.; Lundberg, O.; Lund-Jensen, B.; Lutz, M. S.; Luzi, P. M.; Lynn, D.; Lysak, R.; Lytken, E.; Lyu, F.; Lyubushkin, V.; Ma, H.; Ma, L. L.; Ma, Y.; Maccarrone, G.; Macchiolo, A.; MacDonald, C. M.; Maček, B.; Machado Miguens, J.; Madaffari, D.; Madar, R.; Mader, W. F.; Madsen, A.; Madysa, N.; Maeda, J.; Maeland, S.; Maeno, T.; Maevskiy, A. S.; Magerl, V.; Maiani, C.; Maidantchik, C.; Maier, T.; Maio, A.; Majersky, O.; Majewski, S.; Makida, Y.; Makovec, N.; Malaescu, B.; Malecki, Pa.; Maleev, V. P.; Malek, F.; Mallik, U.; Malon, D.; Malone, C.; Maltezos, S.; Malyukov, S.; Mamuzic, J.; Mancini, G.; Mandić, I.; Maneira, J.; Manhaes de Andrade Filho, L.; Manjarres Ramos, J.; Mankinen, K. H.; Mann, A.; Manousos, A.; Mansoulie, B.; Mansour, J. D.; Mantifel, R.; Mantoani, M.; Manzoni, S.; Mapelli, L.; Marceca, G.; March, L.; Marchese, L.; Marchiori, G.; Marcisovsky, M.; Marin Tobon, C. A.; Marjanovic, M.; Marley, D. E.; Marroquim, F.; Marsden, S. P.; Marshall, Z.; Martensson, M. U. F.; Marti-Garcia, S.; Martin, C. B.; Martin, T. A.; Martin, V. J.; Martin Dit Latour, B.; Martinez, M.; Martinez Outschoorn, V. I.; Martin-Haugh, S.; Martoiu, V. S.; Martyniuk, A. C.; Marzin, A.; Masetti, L.; Mashimo, T.; Mashinistov, R.; Masik, J.; Maslennikov, A. L.; Mason, L. H.; Massa, L.; Mastrandrea, P.; Mastroberardino, A.; Masubuchi, T.; Mättig, P.; Maurer, J.; Maxfield, S. J.; Maximov, D. A.; Mazini, R.; Maznas, I.; Mazza, S. M.; Mc Fadden, N. C.; Mc Goldrick, G.; Mc Kee, S. P.; McCarn, A.; McCarthy, R. L.; McCarthy, T. G.; McClymont, L. I.; McDonald, E. F.; McFayden, J. A.; McHedlidze, G.; McMahon, S. J.; McNamara, P. C.; McNicol, C. J.; McPherson, R. A.; Meehan, S.; Megy, T. J.; Mehlhase, S.; Mehta, A.; Meideck, T.; Meier, K.; Meirose, B.; Melini, D.; Mellado Garcia, B. R.; Mellenthin, J. D.; Melo, M.; Meloni, F.; Melzer, A.; Menary, S. B.; Meng, L.; Meng, X. T.; Mengarelli, A.; Menke, S.; Meoni, E.; Mergelmeyer, S.; Merlassino, C.; Mermod, P.; Merola, L.; Meroni, C.; Merritt, F. S.; Messina, A.; Metcalfe, J.; Mete, A. S.; Meyer, C.; Meyer, J.-P.; Meyer, J.; Meyer Zu Theenhausen, H.; Miano, F.; Middleton, R. P.; Miglioranzi, S.; Mijović, L.; Mikenberg, G.; Mikestikova, M.; Mikuž, M.; Milesi, M.; Milic, A.; Millar, D. A.; Miller, D. W.; Mills, C.; Milov, A.; Milstead, D. A.; Minaenko, A. A.; Minami, Y.; Minashvili, I. A.; Mincer, A. I.; Mindur, B.; Mineev, M.; Minegishi, Y.; Ming, Y.; Mir, L. M.; Mirto, A.; Mistry, K. P.; Mitani, T.; Mitrevski, J.; Mitsou, V. A.; Miucci, A.; Miyagawa, P. S.; Mizukami, A.; Mjörnmark, J. U.; Mkrtchyan, T.; Mlynarikova, M.; Moa, T.; Mochizuki, K.; Mogg, P.; Mohapatra, S.; Molander, S.; Moles-Valls, R.; Mondragon, M. C.; Mönig, K.; Monk, J.; Monnier, E.; Montalbano, A.; Montejo Berlingen, J.; Monticelli, F.; Monzani, S.; Moore, R. W.; Morange, N.; Moreno, D.; Moreno Llácer, M.; Morettini, P.; Morgenstern, S.; Mori, D.; Mori, T.; Morii, M.; Morinaga, M.; Morisbak, V.; Morley, A. K.; Mornacchi, G.; Morris, J. D.; Morvaj, L.; Moschovakos, P.; Mosidze, M.; Moss, H. J.; Moss, J.; Motohashi, K.; Mount, R.; Mountricha, E.; Moyse, E. J. W.; Muanza, S.; Mueller, F.; Mueller, J.; Mueller, R. S. P.; Muenstermann, D.; Mullen, P.; Mullier, G. A.; Munoz Sanchez, F. J.; Murray, W. J.; Musheghyan, H.; Muškinja, M.; Myagkov, A. G.; Myska, M.; Nachman, B. P.; Nackenhorst, O.; Nagai, K.; Nagai, R.; Nagano, K.; Nagasaka, Y.; Nagata, K.; Nagel, M.; Nagy, E.; Nairz, A. M.; Nakahama, Y.; Nakamura, K.; Nakamura, T.; Nakano, I.; Naranjo Garcia, R. F.; Narayan, R.; Narrias Villar, D. I.; Naryshkin, I.; Naumann, T.; Navarro, G.; Nayyar, R.; Neal, H. A.; Nechaeva, P. Yu.; Neep, T. J.; Negri, A.; Negrini, M.; Nektarijevic, S.; Nellist, C.; Nelson, A.; Nelson, M. E.; Nemecek, S.; Nemethy, P.; Nessi, M.; Neubauer, M. S.; Neumann, M.; Newman, P. R.; Ng, T. Y.; Nguyen Manh, T.; Nickerson, R. B.; Nicolaidou, R.; Nielsen, J.; Nikiforou, N.; Nikolaenko, V.; Nikolic-Audit, I.; Nikolopoulos, K.; Nilsen, J. K.; Nilsson, P.; Ninomiya, Y.; Nisati, A.; Nishu, N.; Nisius, R.; Nitsche, I.; Nitta, T.; Nobe, T.; Noguchi, Y.; Nomachi, M.; Nomidis, I.; Nomura, M. A.; Nooney, T.; Nordberg, M.; Norjoharuddeen, N.; Novgorodova, O.; Nozaki, M.; Nozka, L.; Ntekas, K.; Nurse, E.; Nuti, F.; O'Connor, K.; O'Neil, D. C.; O'Rourke, A. A.; O'Shea, V.; Oakham, F. G.; Oberlack, H.; Obermann, T.; Ocariz, J.; Ochi, A.; Ochoa, I.; Ochoa-Ricoux, J. P.; Oda, S.; Odaka, S.; Oh, A.; Oh, S. H.; Ohm, C. C.; Ohman, H.; Oide, H.; Okawa, H.; Okumura, Y.; Okuyama, T.; Olariu, A.; Oleiro Seabra, L. F.; Olivares Pino, S. A.; Oliveira Damazio, D.; Olszewski, A.; Olszowska, J.; Onofre, A.; Onogi, K.; Onyisi, P. U. E.; Oppen, H.; Oreglia, M. J.; Oren, Y.; Orestano, D.; Orlando, N.; Orr, R. S.; Osculati, B.; Ospanov, R.; Otero Y Garzon, G.; Otono, H.; Ouchrif, M.; Ould-Saada, F.; Ouraou, A.; Oussoren, K. P.; Ouyang, Q.; Owen, M.; Owen, R. E.; Ozcan, V. E.; Ozturk, N.; Pachal, K.; Pacheco Pages, A.; Pacheco Rodriguez, L.; Padilla Aranda, C.; Pagan Griso, S.; Paganini, M.; Paige, F.; Palacino, G.; Palazzo, S.; Palestini, S.; Palka, M.; Pallin, D.; Panagiotopoulou, E. St.; Panagoulias, I.; Pandini, C. E.; Panduro Vazquez, J. G.; Pani, P.; Panitkin, S.; Pantea, D.; Paolozzi, L.; Papadopoulou, Th. D.; Papageorgiou, K.; Paramonov, A.; Paredes Hernandez, D.; Parker, A. J.; Parker, M. A.; Parker, K. A.; Parodi, F.; Parsons, J. A.; Parzefall, U.; Pascuzzi, V. R.; Pasner, J. M.; Pasqualucci, E.; Passaggio, S.; Pastore, Fr.; Pataraia, S.; Pater, J. R.; Pauly, T.; Pearson, B.; Pedraza Lopez, S.; Pedro, R.; Peleganchuk, S. V.; Penc, O.; Peng, C.; Peng, H.; Penwell, J.; Peralva, B. S.; Perego, M. M.; Perepelitsa, D. V.; Peri, F.; Perini, L.; Pernegger, H.; Perrella, S.; Peschke, R.; Peshekhonov, V. D.; Peters, K.; Peters, R. F. Y.; Petersen, B. A.; Petersen, T. C.; Petit, E.; Petridis, A.; Petridou, C.; Petroff, P.; Petrolo, E.; Petrov, M.; Petrucci, F.; Pettersson, N. E.; Peyaud, A.; Pezoa, R.; Phillips, F. H.; Phillips, P. W.; Piacquadio, G.; Pianori, E.; Picazio, A.; Pickering, M. A.; Piegaia, R.; Pilcher, J. E.; Pilkington, A. D.; Pinamonti, M.; Pinfold, J. L.; Pirumov, H.; Pitt, M.; Plazak, L.; Pleier, M.-A.; Pleskot, V.; Plotnikova, E.; Pluth, D.; Podberezko, P.; Poettgen, R.; Poggi, R.; Poggioli, L.; Pogrebnyak, I.; Pohl, D.; Pokharel, I.; Polesello, G.; Poley, A.; Policicchio, A.; Polifka, R.; Polini, A.; Pollard, C. S.; Polychronakos, V.; Pommès, K.; Ponomarenko, D.; Pontecorvo, L.; Popeneciu, G. A.; Portillo Quintero, D. M.; Pospisil, S.; Potamianos, K.; Potrap, I. N.; Potter, C. J.; Potti, H.; Poulsen, T.; Poveda, J.; Pozo Astigarraga, M. E.; Pralavorio, P.; Pranko, A.; Prell, S.; Price, D.; Primavera, M.; Prince, S.; Proklova, N.; Prokofiev, K.; Prokoshin, F.; Protopopescu, S.; Proudfoot, J.; Przybycien, M.; Puri, A.; Puzo, P.; Qian, J.; Qin, G.; Qin, Y.; Quadt, A.; Queitsch-Maitland, M.; Quilty, D.; Raddum, S.; Radeka, V.; Radescu, V.; Radhakrishnan, S. K.; Radloff, P.; Rados, P.; Ragusa, F.; Rahal, G.; Raine, J. A.; Rajagopalan, S.; Rangel-Smith, C.; Rashid, T.; Raspopov, S.; Ratti, M. G.; Rauch, D. M.; Rauscher, F.; Rave, S.; Ravinovich, I.; Rawling, J. H.; Raymond, M.; Read, A. L.; Readioff, N. P.; Reale, M.; Rebuzzi, D. M.; Redelbach, A.; Redlinger, G.; Reece, R.; Reed, R. G.; Reeves, K.; Rehnisch, L.; Reichert, J.; Reiss, A.; Rembser, C.; Ren, H.; Rescigno, M.; Resconi, S.; Resseguie, E. D.; Rettie, S.; Reynolds, E.; Rezanova, O. L.; Reznicek, P.; Rezvani, R.; Richter, R.; Richter, S.; Richter-Was, E.; Ricken, O.; Ridel, M.; Rieck, P.; Riegel, C. J.; Rieger, J.; Rifki, O.; Rijssenbeek, M.; Rimoldi, A.; Rimoldi, M.; Rinaldi, L.; Ripellino, G.; Ristić, B.; Ritsch, E.; Riu, I.; Rizatdinova, F.; Rizvi, E.; Rizzi, C.; Roberts, R. T.; Robertson, S. H.; Robichaud-Veronneau, A.; Robinson, D.; Robinson, J. E. M.; Robson, A.; Rocco, E.; Roda, C.; Rodina, Y.; Rodriguez Bosca, S.; Rodriguez Perez, A.; Rodriguez Rodriguez, D.; Roe, S.; Rogan, C. S.; Røhne, O.; Roloff, J.; Romaniouk, A.; Romano, M.; Romano Saez, S. M.; Romero Adam, E.; Rompotis, N.; Ronzani, M.; Roos, L.; Rosati, S.; Rosbach, K.; Rose, P.; Rosien, N.-A.; Rossi, E.; Rossi, L. P.; Rosten, J. H. N.; Rosten, R.; Rotaru, M.; Rothberg, J.; Rousseau, D.; Rozanov, A.; Rozen, Y.; Ruan, X.; Rubbo, F.; Ruettinger, E. M.; Rühr, F.; Ruiz-Martinez, A.; Rurikova, Z.; Rusakovich, N. A.; Russell, H. L.; Rutherfoord, J. P.; Ruthmann, N.; Ryabov, Y. F.; Rybar, M.; Rybkin, G.; Ryu, S.; Ryzhov, A.; Rzehorz, G. F.; Saavedra, A. F.; Sabato, G.; Sacerdoti, S.; Sadrozinski, H. F.-W.; Sadykov, R.; Safai Tehrani, F.; Saha, P.; Sahinsoy, M.; Saimpert, M.; Saito, M.; Saito, T.; Sakamoto, H.; Sakurai, Y.; Salamanna, G.; Salazar Loyola, J. E.; Salek, D.; Sales de Bruin, P. H.; Salihagic, D.; Salnikov, A.; Salt, J.; Salvatore, D.; Salvatore, F.; Salvucci, A.; Salzburger, A.; Sammel, D.; Sampsonidis, D.; Sampsonidou, D.; Sánchez, J.; Sanchez Martinez, V.; Sanchez Pineda, A.; Sandaker, H.; Sandbach, R. L.; Sander, C. O.; Sandhoff, M.; Sandoval, C.; Sankey, D. P. C.; Sannino, M.; Sano, Y.; Sansoni, A.; Santoni, C.; Santos, H.; Santoyo Castillo, I.; Sapronov, A.; Saraiva, J. G.; Sarrazin, B.; Sasaki, O.; Sato, K.; Sauvan, E.; Savage, G.; Savard, P.; Savic, N.; Sawyer, C.; Sawyer, L.; Saxon, J.; Sbarra, C.; Sbrizzi, A.; Scanlon, T.; Scannicchio, D. A.; Schaarschmidt, J.; Schacht, P.; Schachtner, B. M.; Schaefer, D.; Schaefer, L.; Schaefer, R.; Schaeffer, J.; Schaepe, S.; Schaetzel, S.; Schäfer, U.; Schaffer, A. C.; Schaile, D.; Schamberger, R. D.; Schegelsky, V. A.; Scheirich, D.; Schernau, M.; Schiavi, C.; Schier, S.; Schildgen, L. K.; Schillo, C.; Schioppa, M.; Schlenker, S.; Schmidt-Sommerfeld, K. R.; Schmieden, K.; Schmitt, C.; Schmitt, S.; Schmitz, S.; Schnoor, U.; Schoeffel, L.; Schoening, A.; Schoenrock, B. D.; Schopf, E.; Schott, M.; Schouwenberg, J. F. P.; Schovancova, J.; Schramm, S.; Schuh, N.; Schulte, A.; Schultens, M. J.; Schultz-Coulon, H.-C.; Schulz, H.; Schumacher, M.; Schumm, B. A.; Schune, Ph.; Schwartzman, A.; Schwarz, T. A.; Schweiger, H.; Schwemling, Ph.; Schwienhorst, R.; Schwindling, J.; Sciandra, A.; Sciolla, G.; Scornajenghi, M.; Scuri, F.; Scutti, F.; Searcy, J.; Seema, P.; Seidel, S. C.; Seiden, A.; Seixas, J. M.; Sekhniaidze, G.; Sekhon, K.; Sekula, S. J.; Semprini-Cesari, N.; Senkin, S.; Serfon, C.; Serin, L.; Serkin, L.; Sessa, M.; Seuster, R.; Severini, H.; Sfiligoj, T.; Sforza, F.; Sfyrla, A.; Shabalina, E.; Shaikh, N. W.; Shan, L. Y.; Shang, R.; Shank, J. T.; Shapiro, M.; Shatalov, P. B.; Shaw, K.; Shaw, S. M.; Shcherbakova, A.; Shehu, C. Y.; Shen, Y.; Sherafati, N.; Sherwood, P.; Shi, L.; Shimizu, S.; Shimmin, C. O.; Shimojima, M.; Shipsey, I. P. J.; Shirabe, S.; Shiyakova, M.; Shlomi, J.; Shmeleva, A.; Shoaleh Saadi, D.; Shochet, M. J.; Shojaii, S.; Shope, D. R.; Shrestha, S.; Shulga, E.; Shupe, M. A.; Sicho, P.; Sickles, A. M.; Sidebo, P. E.; Sideras Haddad, E.; Sidiropoulou, O.; Sidoti, A.; Siegert, F.; Sijacki, Dj.; Silva, J.; Silverstein, S. B.; Simak, V.; Simic, L.; Simion, S.; Simioni, E.; Simmons, B.; Simon, M.; Sinervo, P.; Sinev, N. B.; Sioli, M.; Siragusa, G.; Siral, I.; Sivoklokov, S. Yu.; Sjölin, J.; Skinner, M. B.; Skubic, P.; Slater, M.; Slavicek, T.; Slawinska, M.; Sliwa, K.; Slovak, R.; Smakhtin, V.; Smart, B. H.; Smiesko, J.; Smirnov, N.; Smirnov, S. Yu.; Smirnov, Y.; Smirnova, L. N.; Smirnova, O.; Smith, J. W.; Smith, M. N. K.; Smith, R. W.; Smizanska, M.; Smolek, K.; Snesarev, A. A.; Snyder, I. M.; Snyder, S.; Sobie, R.; Socher, F.; Soffer, A.; Søgaard, A.; Soh, D. A.; Sokhrannyi, G.; Solans Sanchez, C. A.; Solar, M.; Soldatov, E. Yu.; Soldevila, U.; Solodkov, A. A.; Soloshenko, A.; Solovyanov, O. V.; Solovyev, V.; Sommer, P.; Son, H.; Sopczak, A.; Sosa, D.; Sotiropoulou, C. L.; Sottocornola, S.; Soualah, R.; Soukharev, A. M.; South, D.; Sowden, B. C.; Spagnolo, S.; Spalla, M.; Spangenberg, M.; Spanò, F.; Sperlich, D.; Spettel, F.; Spieker, T. M.; Spighi, R.; Spigo, G.; Spiller, L. A.; Spousta, M.; St. Denis, R. D.; Stabile, A.; Stamen, R.; Stamm, S.; Stanecka, E.; Stanek, R. W.; Stanescu, C.; Stanitzki, M. M.; Stapf, B. S.; Stapnes, S.; Starchenko, E. A.; Stark, G. H.; Stark, J.; Stark, S. H.; Staroba, P.; Starovoitov, P.; Stärz, S.; Staszewski, R.; Stegler, M.; Steinberg, P.; Stelzer, B.; Stelzer, H. J.; Stelzer-Chilton, O.; Stenzel, H.; Stevenson, T. J.; Stewart, G. A.; Stockton, M. C.; Stoebe, M.; Stoicea, G.; Stolte, P.; Stonjek, S.; Stradling, A. R.; Straessner, A.; Stramaglia, M. E.; Strandberg, J.; Strandberg, S.; Strauss, M.; Strizenec, P.; Ströhmer, R.; Strom, D. M.; Stroynowski, R.; Strubig, A.; Stucci, S. A.; Stugu, B.; Styles, N. A.; Su, D.; Su, J.; Suchek, S.; Sugaya, Y.; Suk, M.; Sulin, V. V.; Sultan, D. M. S.; Sultansoy, S.; Sumida, T.; Sun, S.; Sun, X.; Suruliz, K.; Suster, C. J. E.; Sutton, M. R.; Suzuki, S.; Svatos, M.; Swiatlowski, M.; Swift, S. P.; Sykora, I.; Sykora, T.; Ta, D.; Tackmann, K.; Taenzer, J.; Taffard, A.; Tafirout, R.; Tahirovic, E.; Taiblum, N.; Takai, H.; Takashima, R.; Takasugi, E. H.; Takeda, K.; Takeshita, T.; Takubo, Y.; Talby, M.; Talyshev, A. A.; Tanaka, J.; Tanaka, M.; Tanaka, R.; Tanaka, S.; Tanioka, R.; Tannenwald, B. B.; Tapia Araya, S.; Tapprogge, S.; Tarem, S.; Tartarelli, G. F.; Tas, P.; Tasevsky, M.; Tashiro, T.; Tassi, E.; Tavares Delgado, A.; Tayalati, Y.; Taylor, A. C.; Taylor, A. J.; Taylor, G. N.; Taylor, P. T. E.; Taylor, W.; Teixeira-Dias, P.; Temple, D.; Ten Kate, H.; Teng, P. K.; Teoh, J. J.; Tepel, F.; Terada, S.; Terashi, K.; Terron, J.; Terzo, S.; Testa, M.; Teuscher, R. J.; Thais, S. J.; Theveneaux-Pelzer, T.; Thiele, F.; Thomas, J. P.; Thomas-Wilsker, J.; Thompson, P. D.; Thompson, A. S.; Thomsen, L. A.; Thomson, E.; Tian, Y.; Tibbetts, M. J.; Ticse Torres, R. E.; Tikhomirov, V. O.; Tikhonov, Yu. A.; Timoshenko, S.; Tipton, P.; Tisserant, S.; Todome, K.; Todorova-Nova, S.; Todt, S.; Tojo, J.; Tokár, S.; Tokushuku, K.; Tolley, E.; Tomlinson, L.; Tomoto, M.; Tompkins, L.; Toms, K.; Tong, B.; Tornambe, P.; Torrence, E.; Torres, H.; Torró Pastor, E.; Toth, J.; Touchard, F.; Tovey, D. R.; Treado, C. J.; Trefzger, T.; Tresoldi, F.; Tricoli, A.; Trigger, I. M.; Trincaz-Duvoid, S.; Tripiana, M. F.; Trischuk, W.; Trocmé, B.; Trofymov, A.; Troncon, C.; Trottier-McDonald, M.; Trovatelli, M.; Truong, L.; Trzebinski, M.; Trzupek, A.; Tsang, K. W.; Tseng, J. C.-L.; Tsiareshka, P. V.; Tsipolitis, G.; Tsirintanis, N.; Tsiskaridze, S.; Tsiskaridze, V.; Tskhadadze, E. G.; Tsukerman, I. I.; Tsulaia, V.; Tsuno, S.; Tsybychev, D.; Tu, Y.; Tudorache, A.; Tudorache, V.; Tulbure, T. T.; Tuna, A. N.; Turchikhin, S.; Turgeman, D.; Turk Cakir, I.; Turra, R.; Tuts, P. M.; Ucchielli, G.; Ueda, I.; Ughetto, M.; Ukegawa, F.; Unal, G.; Undrus, A.; Unel, G.; Ungaro, F. C.; Unno, Y.; Uno, K.; Unverdorben, C.; Urban, J.; Urquijo, P.; Urrejola, P.; Usai, G.; Usui, J.; Vacavant, L.; Vacek, V.; Vachon, B.; Vadla, K. O. H.; Vaidya, A.; Valderanis, C.; Valdes Santurio, E.; Valente, M.; Valentinetti, S.; Valero, A.; Valéry, L.; Valkar, S.; Vallier, A.; Valls Ferrer, J. A.; van den Wollenberg, W.; van der Graaf, H.; van Gemmeren, P.; van Nieuwkoop, J.; van Vulpen, I.; van Woerden, M. C.; Vanadia, M.; Vandelli, W.; Vaniachine, A.; Vankov, P.; Vardanyan, G.; Vari, R.; Varnes, E. W.; Varni, C.; Varol, T.; Varouchas, D.; Vartapetian, A.; Varvell, K. E.; Vasquez, J. G.; Vasquez, G. A.; Vazeille, F.; Vazquez Furelos, D.; Vazquez Schroeder, T.; Veatch, J.; Veeraraghavan, V.; Veloce, L. M.; Veloso, F.; Veneziano, S.; Ventura, A.; Venturi, M.; Venturi, N.; Venturini, A.; Vercesi, V.; Verducci, M.; Verkerke, W.; Vermeulen, A. T.; Vermeulen, J. C.; Vetterli, M. C.; Viaux Maira, N.; Viazlo, O.; Vichou, I.; Vickey, T.; Vickey Boeriu, O. E.; Viehhauser, G. H. A.; Viel, S.; Vigani, L.; Villa, M.; Villaplana Perez, M.; Vilucchi, E.; Vincter, M. G.; Vinogradov, V. B.; Vishwakarma, A.; Vittori, C.; Vivarelli, I.; Vlachos, S.; Vogel, M.; Vokac, P.; Volpi, G.; von der Schmitt, H.; von Toerne, E.; Vorobel, V.; Vorobev, K.; Vos, M.; Voss, R.; Vossebeld, J. H.; Vranjes, N.; Vranjes Milosavljevic, M.; Vrba, V.; Vreeswijk, M.; Vuillermet, R.; Vukotic, I.; Wagner, P.; Wagner, W.; Wagner-Kuhr, J.; Wahlberg, H.; Wahrmund, S.; Walder, J.; Walker, R.; Walkowiak, W.; Wallangen, V.; Wang, C.; Wang, C.; Wang, F.; Wang, H.; Wang, H.; Wang, J.; Wang, J.; Wang, Q.; Wang, R.-J.; Wang, R.; Wang, S. M.; Wang, T.; Wang, W.; Wang, W.; Wang, Z.; Wanotayaroj, C.; Warburton, A.; Ward, C. P.; Wardrope, D. R.; Washbrook, A.; Watkins, P. M.; Watson, A. T.; Watson, M. F.; Watts, G.; Watts, S.; Waugh, B. M.; Webb, A. F.; Webb, S.; Weber, M. S.; Weber, S. M.; Weber, S. W.; Weber, S. A.; Webster, J. S.; Weidberg, A. R.; Weinert, B.; Weingarten, J.; Weirich, M.; Weiser, C.; Weits, H.; Wells, P. S.; Wenaus, T.; Wengler, T.; Wenig, S.; Wermes, N.; Werner, M. D.; Werner, P.; Wessels, M.; Weston, T. D.; Whalen, K.; Whallon, N. L.; Wharton, A. M.; White, A. S.; White, A.; White, M. J.; White, R.; Whiteson, D.; Whitmore, B. W.; Wickens, F. J.; Wiedenmann, W.; Wielers, M.; Wiglesworth, C.; Wiik-Fuchs, L. A. M.; Wildauer, A.; Wilk, F.; Wilkens, H. G.; Williams, H. H.; Williams, S.; Willis, C.; Willocq, S.; Wilson, J. A.; Wingerter-Seez, I.; Winkels, E.; Winklmeier, F.; Winston, O. J.; Winter, B. T.; Wittgen, M.; Wobisch, M.; Wolf, A.; Wolf, T. M. H.; Wolff, R.; Wolter, M. W.; Wolters, H.; Wong, V. W. S.; Woods, N. L.; Worm, S. D.; Wosiek, B. K.; Wotschack, J.; Wozniak, K. W.; Wu, M.; Wu, S. L.; Wu, X.; Wu, Y.; Wyatt, T. R.; Wynne, B. M.; Xella, S.; Xi, Z.; Xia, L.; Xu, D.; Xu, L.; Xu, T.; Xu, W.; Yabsley, B.; Yacoob, S.; Yamaguchi, D.; Yamaguchi, Y.; Yamamoto, A.; Yamamoto, S.; Yamanaka, T.; Yamane, F.; Yamatani, M.; Yamazaki, T.; Yamazaki, Y.; Yan, Z.; Yang, H.; Yang, H.; Yang, Y.; Yang, Z.; Yao, W.-M.; Yap, Y. C.; Yasu, Y.; Yatsenko, E.; Yau Wong, K. H.; Ye, J.; Ye, S.; Yeletskikh, I.; Yigitbasi, E.; Yildirim, E.; Yorita, K.; Yoshihara, K.; Young, C.; Young, C. J. S.; Yu, J.; Yu, J.; Yuen, S. P. Y.; Yusuff, I.; Zabinski, B.; Zacharis, G.; Zaidan, R.; Zaitsev, A. M.; Zakharchuk, N.; Zalieckas, J.; Zaman, A.; Zambito, S.; Zanzi, D.; Zeitnitz, C.; Zemaityte, G.; Zemla, A.; Zeng, J. C.; Zeng, Q.; Zenin, O.; Ženiš, T.; Zerwas, D.; Zhang, D.; Zhang, D.; Zhang, F.; Zhang, G.; Zhang, H.; Zhang, J.; Zhang, L.; Zhang, L.; Zhang, M.; Zhang, P.; Zhang, R.; Zhang, R.; Zhang, X.; Zhang, Y.; Zhang, Z.; Zhao, X.; Zhao, Y.; Zhao, Z.; Zhemchugov, A.; Zhou, B.; Zhou, C.; Zhou, L.; Zhou, M.; Zhou, M.; Zhou, N.; Zhu, C. G.; Zhu, H.; Zhu, J.; Zhu, Y.; Zhuang, X.; Zhukov, K.; Zibell, A.; Zieminska, D.; Zimine, N. I.; Zimmermann, C.; Zimmermann, S.; Zinonos, Z.; Zinser, M.; Ziolkowski, M.; Živković, L.; Zobernig, G.; Zoccoli, A.; Zou, R.; Zur Nedden, M.; Zwalinski, L.; Atlas Collaboration

2018-02-01

A detailed study of multiparticle azimuthal correlations is presented using p p data at √{s }=5.02 and 13 TeV, and p +Pb data at √{sNN}=5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants cn{4 } and flow coefficients vn{4 } =(-cn{4 } ) 1 /4 for n =2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of cn{4 } are obtained as a function of the average number of charged particles per event, <" close=">Nch>">Nch, using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to cn{4 } . The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c2{4 } , and therefore a well-defined v2{4 } , nearly independent of Measurement of long-range multiparticle azimuthal correlations with the subevent cumulant method in p p and p +Pb collisions with the ATLAS detector at the CERN Large Hadron Collider

DOE PAGES

Aaboud, M.; Aad, G.; Abbott, B.; ...

2018-02-12

A detailed study of multiparticle azimuthal correlations is presented using pp data at √s = 5.02 and 13 TeV, and p+Pb data at √ sNN = 5.02 TeV, recorded with the ATLAS detector at the CERN Large Hadron Collider. The azimuthal correlations are probed using four-particle cumulants c n {4} and flow coefficients v n {4} = (-c n{4}) 1/4 for n = 2 and 3, with the goal of extracting long-range multiparticle azimuthal correlation signals and suppressing the short-range correlations. The values of c n {4} are obtained as a function of the average number of charged particles permore » event, (N ch), using the recently proposed two-subevent and three-subevent cumulant methods, and compared with results obtained with the standard cumulant method. The standard method is found to be strongly biased by short-range correlations, which originate mostly from jets with a positive contribution to c n {4}. The three-subevent method, on the other hand, is found to be least sensitive to short-range correlations. The three-subevent method gives a negative c 2 {4}, and therefore a well-defined v 2 {4}, nearly independent of (N ch), which implies that the long-range multiparticle azimuthal correlations persist to events with low multiplicity. Furthermore, v 2 {4} is found to be smaller than the v 2 {2} measured using the two-particle correlation method, as expected for long-range collective behavior. Finally, the measured values of v 2 {4} and v 2 {2} are used to estimate the number of sources relevant for the initial eccentricity in the collision geometry. The results based on the subevent cumulant technique provide direct evidence, in small collision systems, for a long-range collectivity involving many particles distributed across a broad rapidity interval.« less

Physics with e{sup +}e{sup -} Linear Colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Barklow, Timothy L

2003-05-05

We describe the physics potential of e{sup +}e{sup -} linear colliders in this report. These machines are planned to operate in the first phase at a center-of-mass energy of 500 GeV, before being scaled up to about 1 TeV. In the second phase of the operation, a final energy of about 2 TeV is expected. The machines will allow us to perform precision tests of the heavy particles in the Standard Model, the top quark and the electroweak bosons. They are ideal facilities for exploring the properties of Higgs particles, in particular in the intermediate mass range. New vector bosonsmore » and novel matter particles in extended gauge theories can be searched for and studied thoroughly. The machines provide unique opportunities for the discovery of particles in supersymmetric extensions of the Standard Model, the spectrum of Higgs particles, the supersymmetric partners of the electroweak gauge and Higgs bosons, and of the matter particles. High precision analyses of their properties and interactions will allow for extrapolations to energy scales close to the Planck scale where gravity becomes significant. In alternative scenarios, like compositeness models, novel matter particles and interactions can be discovered and investigated in the energy range above the existing colliders up to the TeV scale. Whatever scenario is realized in Nature, the discovery potential of e{sup +}e{sup -} linear colliders and the high-precision with which the properties of particles and their interactions can be analyzed, define an exciting physics programme complementary to hadron machines.« less

Pair Production of the Doubly Charged Leptons Associated with a Gauge Boson γ or Z in e+e- and γγ Collisions at Future Linear Colliders

NASA Astrophysics Data System (ADS)

Zeng, Qing-Guo; Ji, Li; Yang, Shuo

2015-03-01

In this paper, we investigate the production of a pair of doubly charged leptons associated with a gauge boson V(γ or Z) at future linear colliders via e+e- and γγ collisions. The numerical results show that the possible signals of the doubly charged leptons may be detected via the processes e+e- → VX++X-- and γγ → VX++X-- at future ILC or CLIC experiments. Supported in part by the National Natural Science Foundation of China under Grants Nos. 11275088, 11205023, 11375248 and the Program for Liaoning Excellent Talents in University under Grant No. LJQ2014135

Mechanism of vacuum breakdown in radio-frequency accelerating structures

NASA Astrophysics Data System (ADS)

Barengolts, S. A.; Mesyats, V. G.; Oreshkin, V. I.; Oreshkin, E. V.; Khishchenko, K. V.; Uimanov, I. V.; Tsventoukh, M. M.

2018-06-01

It has been investigated whether explosive electron emission may be the initiating mechanism of vacuum breakdown in the accelerating structures of TeV linear electron-positron colliders (Compact Linear Collider). The physical processes involved in a dc vacuum breakdown have been considered, and the relationship between the voltage applied to the diode and the time delay to breakdown has been found. Based on the results obtained, the development of a vacuum breakdown in an rf electric field has been analyzed and the main parameters responsible for the initiation of explosive electron emission have been estimated. The formation of craters on the cathode surface during explosive electron emission has been numerically simulated, and the simulation results are discussed.

Online beam energy measurement of Beijing electron positron collider II linear accelerator

NASA Astrophysics Data System (ADS)

Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

2016-02-01

This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

Online beam energy measurement of Beijing electron positron collider II linear accelerator.

PubMed

Wang, S; Iqbal, M; Liu, R; Chi, Y

2016-02-01

This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

Low emittance electron storage rings

NASA Astrophysics Data System (ADS)

Levichev, E. B.

2018-01-01

Low-emittance electron (positron) beams are essential for synchrotron light sources, linear collider damping rings, and circular Crab Waist colliders. In this review, the principles and methods of emittance minimization are discussed, prospects for developing relativistic electron storage rings with small beam phase volume are assessed, and problems related to emittance minimization are examined together with their possible solutions. The special features and engineering implementation aspects of various facilities are briefly reviewed.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bane, K.L.F.; Adolphsen, C.; Li, Z.

In a future linear collider, such as the International Linear Collider (ILC), trains of high current, low emittance bunches will be accelerated in a linac before colliding at the interaction point. Asymmetries in the accelerating cavities of the linac will generate fields that will kick the beam transversely and degrade the beam emittance and thus the collider performance. In the main linac of the ILC, which is filled with TESLA-type superconducting cavities, it is the fundamental (FM) and higher mode (HM) couplers that are asymmetric and thus the source of such kicks. The kicks are of two types: one, duemore » to (the asymmetry in) the fundamental RF fields and the other, due to transverse wakefields that are generated by the beam even when it is on axis. In this report we calculate the strength of these kicks and estimate their effect on the ILC beam. The TESLA cavity comprises nine cells, one HM coupler in the upstream end, and one (identical, though rotated) HM coupler and one FM coupler in the downstream end (for their shapes and location see Figs. 1, 2) [1]. The cavity is 1.1 m long, the iris radius 35 mm, and the coupler beam pipe radius 39 mm. Note that the couplers reach closer to the axis than the irises, down to a distance of 30 mm.« less

Left-handed and right-handed U(1) gauge symmetry

NASA Astrophysics Data System (ADS)

Nomura, Takaaki; Okada, Hiroshi

2018-01-01

We propose a model with the left-handed and right-handed continuous Abelian gauge symmetry; U(1) L × U(1) R . Then three right-handed neutrinos are naturally required to achieve U(1) R anomaly cancellations, while several mirror fermions are also needed to do U(1) L anomaly cancellations. Then we formulate the model, and discuss its testability of the new gauge interactions at collider physics such as the large hadron collider (LHC) and the international linear collider (ILC). In particular, we can investigate chiral structure of the interactions by the analysis of forward-backward asymmetry based on polarized beam at the ILC.

Commissioning and initial experience with the ALICE on-line

NASA Astrophysics Data System (ADS)

Altini, V.; Anticic, T.; Carena, F.; Carena, W.; Chapeland, S.; Chibante Barroso, V.; Costa, F.; Dénes, E.; Divià, R.; Fuchs, U.; Kiss, T.; Makhlyueva, I.; Roukoutakis, F.; Schossmaier, K.; Soós, C.; Vande Vyvre, P.; von Haller, B.; ALICE Collaboration

2010-04-01

ALICE (A Large Ion Collider Experiment) is the heavy-ion detector designed to study the physics of strongly interacting matter and the quark-gluon plasma at the CERN Large Hadron Collider (LHC). A large bandwidth and flexible Data Acquisition System (DAQ) has been designed and deployed to collect sufficient statistics in the short running time available per year for heavy ions and to accommodate very different requirements originated from the 18 sub-detectors. This paper will present the large scale tests conducted to assess the standalone DAQ performances, the interfaces with the other online systems and the extensive commissioning performed in order to be fully prepared for physics data taking. It will review the experience accumulated since May 2007 during the standalone commissioning of the main detectors and the global cosmic runs and the lessons learned from this exposure on the "battle field". It will also discuss the test protocol followed to integrate and validate each sub-detector with the online systems and it will conclude with the first results of the LHC injection tests and startup in September 2008. Several papers of the same conference present in more details some elements of the ALICE DAQ system.

Evidence for x -dependent proton color fluctuations in p A collisions at the CERN Large Hadron Collider

DOE PAGES

Alvioli, M.; Cole, B. A.; Frankfurt, L.; ...

2016-01-21

The centrality dependence of forward jet production in pA collisions at the Large Hadron Collider (LHC) has been found to grossly violate the Glauber model prediction in a way that depends on the x in the proton. In this paper, we argue that this modification pattern provides the first experimental evidence for x-dependent proton color fluctuation effects. On average, parton configurations in the projectile proton containing a parton with large x interact with a nuclear target with a significantly smaller than average cross section and have smaller than average size. We implement the effects of fluctuations of the interaction strengthmore » and, using the ATLAS analysis of how hadron production at backward rapidities depends on the number of wounded nucleons, make quantitative predictions for the centrality dependence of the jet production rate as a function of the x-dependent interaction strength σ(x). We find that σ(x) ~ 0.6(σ) gives a good description of the data at x = 0.6. Finally, these findings support an explanation of the European Muon Collaboration effect as arising from the suppression of small-size nucleon configurations in the nucleus.« less

Electromagnetic fields in small systems from a multiphase transport model

NASA Astrophysics Data System (ADS)

Zhao, Xin-Li; Ma, Yu-Gang; Ma, Guo-Liang

2018-02-01

We calculate the electromagnetic fields generated in small systems by using a multiphase transport (AMPT) model. Compared to A +A collisions, we find that the absolute electric and magnetic fields are not small in p +Au and d +Au collisions at energies available at the BNL Relativistic Heavy Ion Collider and in p +Pb collisions at energies available at the CERN Large Hadron Collider. We study the centrality dependencies and the spatial distributions of electromagnetic fields. We further investigate the azimuthal fluctuations of the magnetic field and its correlation with the fluctuating geometry using event-by-event simulations. We find that the azimuthal correlation 〈" close="〉cos(ϕα+ϕβ-2 ΨRP)〉">cos2 (ΨB-Ψ2) between the magnetic field direction and the second-harmonic participant plane is almost zero in small systems with high multiplicities, but not in those with low multiplicities. This indicates that the charge azimuthal correlation is not a valid probe to study the chiral magnetic effect (CME) in small systems with high multiplicities. However, we suggest searching for possible CME effects in small systems with low multiplicities.

Using Data from the Large Hadron Collider in the Classroom

NASA Astrophysics Data System (ADS)

Smith, Jeremy

2017-01-01

Now is an exciting time for physics students, because they have access to technology and experiments all over the world that were unthinkable a generation ago. Therefore, now is also the ideal time to bring these experiments into the classroom, so students can see what cutting edge science looks like, both in terms of the underlying physics and in terms of the technology used to gather data. With the continued running of the Large Hadron Collider at CERN, and the lab's continued dedication to providing open, worldwide access to their data, there is a unique opportunity for students to use these data in a manner very similar to how it's done in the particle physics community. In this session, we will explore ways for students to analyze real data from the CMS experiment at the LHC, plot these data to discover patterns and signals, and use these plots to determine quantities such as the invariant masses of the W, Z and Higgs bosons. Furthermore, we will show how such activities already fit well into standard introductory physics classes, and can in fact enhance already-existing lessons in the topics of momentum, kinematics, energy and electromagnetism.

Probing anomalous W W γ triple gauge bosons coupling at the LHeC

NASA Astrophysics Data System (ADS)

Li, Ruibo; Shen, Xiao-Min; Wang, Kai; Xu, Tao; Zhang, Liangliang; Zhu, Guohuai

2018-04-01

The precision measurement of the W W γ vertex at the future Large Hadron electron Collider (LHeC) at CERN is discussed in this paper. We propose to measure this vertex in the e-p →e-W±j channel as a complement to the conventional charged current νeγ j channel. In addition to the cross section measurement, χ2 method studies of angular variables provide powerful tools to probe the anomalous structure of triple gauge boson couplings. We study the distribution of the well-known azimuthal angle between the final state forward electron and jet in this vector-boson fusion process. On the other hand, full reconstruction of leptonic W decay opens a new opportunity to measure W polarization that is also sensitive to the anomalous triple gauge boson couplings. Taking into consideration the superior determination of parton distribution functions based on future LHeC data, the constraints of λγ and Δ κγ might reach up to O (10-3) level in the most ideal case with the 2 - 3 ab-1 data set, which shows a potential advantage compared to those from LHC and Large Electron-Positron Collider (LEP) data.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Calva-Tellez, E.

The angular distributions of the process e/sup +/e/sup -/ yields e/sup +/e/sup / measured by the Bologna-CERN-Frascati group at the electron-positron colliding-beam facility Adonc are analyzed in terms of standard quantum 3/ including soft-and hard-photon emission. An analytical expression is given for the cross section of the process e/sup +/e/sup -/ yields e/sup +/e gamma for hard photons. Detailed numerical r esults for that specific experimental setup are obtained by a Monte Carlo progrm. It is found that this bremsstrahlung process is responsible for the noncollinear and noncoplanar events observed at Frasscati. Therefore, these data, together with the present calculation,more » provide a test of QED for this particular physical situation involving high energies and large momentum transfers. (auth)« less

Answering Gauguin’s Questions: Where Are We Coming From, Where Are We Going, and What Are We?

ScienceCinema

Ellis, John [CERN

2017-12-09

The knowledge of matter revealed by the current reigning theory of particle physics, the so-called Standard Model, still leaves open many basic questions. What is the origin of the matter in the Universe? How does its mass originate? What is the nature of the dark matter that fills the Universe? Are there additional dimensions of space? The Large Hadron Collider (LHC) at the CERN Laboratory in Geneva, Switzerland, where high-energy experiments have now started, will take physics into a new realm of energy and time, and will address these physics analogues of Gauguin's questions. The answers will set the stage for possible future experiments beyond the scope of the LHC.

Measurement of the W+W- production cross section in pp collisions at a centre-of-mass energy of √{ s} = 13 TeV with the ATLAS experiment

NASA Astrophysics Data System (ADS)

Aaboud, M.; Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Abeloos, B.; Aben, R.; Abouzeid, O. S.; Abraham, N. L.; Abramowicz, H.; Abreu, H.; Abreu, R.; Abulaiti, Y.; Acharya, B. S.; Adachi, S.; Adamczyk, L.; Adams, D. L.; Adelman, J.; Adomeit, S.; Adye, T.; Affolder, A. A.; Agatonovic-Jovin, T.; Aguilar-Saavedra, J. A.; Ahlen, S. P.; Ahmadov, F.; Aielli, G.; Akerstedt, H.; Åkesson, T. P. A.; Akimov, A. V.; Alberghi, G. L.; Albert, J.; Albrand, S.; Alconada Verzini, M. J.; Aleksa, M.; Aleksandrov, I. N.; Alexa, C.; Alexander, G.; Alexopoulos, T.; Alhroob, M.; Ali, B.; Aliev, M.; Alimonti, G.; Alison, J.; Alkire, S. P.; Allbrooke, B. M. M.; Allen, B. W.; Allport, P. P.; Aloisio, A.; Alonso, A.; Alonso, F.; Alpigiani, C.; Alshehri, A. A.; Alstaty, M.; Alvarez Gonzalez, B.; Álvarez Piqueras, D.; Alviggi, M. G.; Amadio, B. T.; Amaral Coutinho, Y.; Amelung, C.; Amidei, D.; Amor Dos Santos, S. P.; Amorim, A.; Amoroso, S.; Amundsen, G.; Anastopoulos, C.; Ancu, L. S.; Andari, N.; Andeen, T.; Anders, C. F.; Anders, G.; Anders, J. K.; Anderson, K. J.; Andreazza, A.; Andrei, V.; Angelidakis, S.; Angelozzi, I.; Angerami, A.; Anghinolfi, F.; Anisenkov, A. V.; Anjos, N.; Annovi, A.; Antel, C.; Antonelli, M.; Antonov, A.; Antrim, D. J.; Anulli, F.; Aoki, M.; Aperio Bella, L.; Arabidze, G.; Arai, Y.; Araque, J. P.; Arce, A. T. H.; Arduh, F. A.; Arguin, J.-F.; Argyropoulos, S.; Arik, M.; Armbruster, A. J.; Armitage, L. J.; Arnaez, O.; Arnold, H.; Arratia, M.; Arslan, O.; Artamonov, A.; Artoni, G.; Artz, S.; Asai, S.; Asbah, N.; Ashkenazi, A.; Åsman, B.; Asquith, L.; Assamagan, K.; Astalos, R.; Atkinson, M.; Atlay, N. B.; Augsten, K.; Avolio, G.; Axen, B.; Ayoub, M. K.; Azuelos, G.; Baak, M. A.; Baas, A. E.; Baca, M. J.; Bachacou, H.; Bachas, K.; Backes, M.; Backhaus, M.; Bagiacchi, P.; Bagnaia, P.; Bai, Y.; Baines, J. T.; Bajic, M.; Baker, O. K.; Baldin, E. M.; Balek, P.; Balestri, T.; Balli, F.; Balunas, W. K.; Banas, E.; Banerjee, Sw.; Bannoura, A. A. 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H.; Hopkins, W. H.; Horii, Y.; Horton, A. J.; Hostachy, J.-Y.; Hou, S.; Hoummada, A.; Howarth, J.; Hoya, J.; Hrabovsky, M.; Hristova, I.; Hrivnac, J.; Hryn'ova, T.; Hrynevich, A.; Hsu, P. J.; Hsu, S.-C.; Hu, Q.; Hu, S.; Huang, Y.; Hubacek, Z.; Hubaut, F.; Huegging, F.; Huffman, T. B.; Hughes, E. W.; Hughes, G.; Huhtinen, M.; Huo, P.; Huseynov, N.; Huston, J.; Huth, J.; Iacobucci, G.; Iakovidis, G.; Ibragimov, I.; Iconomidou-Fayard, L.; Ideal, E.; Idrissi, Z.; Iengo, P.; Igonkina, O.; Iizawa, T.; Ikegami, Y.; Ikeno, M.; Ilchenko, Y.; Iliadis, D.; Ilic, N.; Introzzi, G.; Ioannou, P.; Iodice, M.; Iordanidou, K.; Ippolito, V.; Ishijima, N.; Ishino, M.; Ishitsuka, M.; Ishmukhametov, R.; Issever, C.; Istin, S.; Ito, F.; Iturbe Ponce, J. M.; Iuppa, R.; Iwanski, W.; Iwasaki, H.; Izen, J. M.; Izzo, V.; Jabbar, S.; Jackson, B.; Jackson, P.; Jain, V.; Jakobi, K. B.; Jakobs, K.; Jakobsen, S.; Jakoubek, T.; Jamin, D. O.; Jana, D. K.; Jansky, R.; Janssen, J.; Janus, M.; Janus, P. A.; Jarlskog, G.; Javadov, N.; Javůrek, T.; Javurkova, M.; Jeanneau, F.; Jeanty, L.; Jejelava, J.; Jeng, G.-Y.; Jennens, D.; Jenni, P.; Jeske, C.; Jézéquel, S.; Ji, H.; Jia, J.; Jiang, H.; Jiang, Y.; Jiang, Z.; Jiggins, S.; Jimenez Pena, J.; Jin, S.; Jinaru, A.; Jinnouchi, O.; Jivan, H.; Johansson, P.; Johns, K. A.; Johnson, W. J.; Jon-And, K.; Jones, G.; Jones, R. W. L.; Jones, S.; Jones, T. J.; Jongmanns, J.; Jorge, P. M.; Jovicevic, J.; Ju, X.; Juste Rozas, A.; Köhler, M. K.; Kaczmarska, A.; Kado, M.; Kagan, H.; Kagan, M.; Kahn, S. J.; Kaji, T.; Kajomovitz, E.; Kalderon, C. W.; Kaluza, A.; Kama, S.; Kamenshchikov, A.; Kanaya, N.; Kaneti, S.; Kanjir, L.; Kantserov, V. A.; Kanzaki, J.; Kaplan, B.; Kaplan, L. S.; Kapliy, A.; Kar, D.; Karakostas, K.; Karamaoun, A.; Karastathis, N.; Kareem, M. J.; Karentzos, E.; Karnevskiy, M.; Karpov, S. N.; Karpova, Z. M.; Karthik, K.; Kartvelishvili, V.; Karyukhin, A. N.; Kasahara, K.; Kashif, L.; Kass, R. D.; Kastanas, A.; Kataoka, Y.; Kato, C.; Katre, A.; Katzy, J.; Kawade, K.; Kawagoe, K.; Kawamoto, T.; Kawamura, G.; Kazanin, V. F.; Keeler, R.; Kehoe, R.; Keller, J. S.; Kempster, J. J.; Keoshkerian, H.; Kepka, O.; Kerševan, B. P.; Kersten, S.; Keyes, R. A.; Khader, M.; Khalil-Zada, F.; Khanov, A.; Kharlamov, A. G.; Kharlamova, T.; Khoo, T. J.; Khovanskiy, V.; Khramov, E.; Khubua, J.; Kido, S.; Kilby, C. R.; Kim, H. Y.; Kim, S. H.; Kim, Y. K.; Kimura, N.; Kind, O. M.; King, B. T.; King, M.; Kirk, J.; Kiryunin, A. E.; Kishimoto, T.; Kisielewska, D.; Kiss, F.; Kiuchi, K.; Kivernyk, O.; Kladiva, E.; Klein, M. H.; Klein, M.; Klein, U.; Kleinknecht, K.; Klimek, P.; Klimentov, A.; Klingenberg, R.; Klioutchnikova, T.; Kluge, E.-E.; Kluit, P.; Kluth, S.; Knapik, J.; Kneringer, E.; Knoops, E. B. F. G.; Knue, A.; Kobayashi, A.; Kobayashi, D.; Kobayashi, T.; Kobel, M.; Kocian, M.; Kodys, P.; Koffas, T.; Koffeman, E.; Köhler, N. M.; Koi, T.; Kolanoski, H.; Kolb, M.; Koletsou, I.; Komar, A. A.; Komori, Y.; Kondo, T.; Kondrashova, N.; Köneke, K.; König, A. C.; Kono, T.; Konoplich, R.; Konstantinidis, N.; Kopeliansky, R.; Koperny, S.; Köpke, L.; Kopp, A. K.; Korcyl, K.; Kordas, K.; Korn, A.; Korol, A. A.; Korolkov, I.; Korolkova, E. V.; Kortner, O.; Kortner, S.; Kosek, T.; Kostyukhin, V. V.; Kotwal, A.; Koulouris, A.; Kourkoumeli-Charalampidi, A.; Kourkoumelis, C.; Kouskoura, V.; Kowalewska, A. B.; Kowalewski, R.; Kowalski, T. Z.; Kozakai, C.; Kozanecki, W.; Kozhin, A. S.; Kramarenko, V. A.; Kramberger, G.; Krasnopevtsev, D.; Krasny, M. W.; Krasznahorkay, A.; Kravchenko, A.; Kretz, M.; Kretzschmar, J.; Kreutzfeldt, K.; Krieger, P.; Krizka, K.; Kroeninger, K.; Kroha, H.; Kroll, J.; Kroseberg, J.; Krstic, J.; Kruchonak, U.; Krüger, H.; Krumnack, N.; Kruse, M. C.; Kruskal, M.; Kubota, T.; Kucuk, H.; Kuday, S.; Kuechler, J. T.; Kuehn, S.; Kugel, A.; Kuger, F.; Kuhl, T.; Kukhtin, V.; Kukla, R.; Kulchitsky, Y.; Kuleshov, S.; Kuna, M.; Kunigo, T.; Kupco, A.; Kurashige, H.; Kurchaninov, L. L.; Kurochkin, Y. A.; Kurth, M. G.; Kus, V.; Kuwertz, E. S.; Kuze, M.; Kvita, J.; Kwan, T.; Kyriazopoulos, D.; La Rosa, A.; La Rosa Navarro, J. L.; La Rotonda, L.; Lacasta, C.; Lacava, F.; Lacey, J.; Lacker, H.; Lacour, D.; Lacuesta, V. R.; Ladygin, E.; Lafaye, R.; Laforge, B.; Lagouri, T.; Lai, S.; Lammers, S.; Lampl, W.; Lançon, E.; Landgraf, U.; Landon, M. P. J.; Lanfermann, M. C.; Lang, V. S.; Lange, J. C.; Lankford, A. J.; Lanni, F.; Lantzsch, K.; Lanza, A.; Laplace, S.; Lapoire, C.; Laporte, J. F.; Lari, T.; Lasagni Manghi, F.; Lassnig, M.; Laurelli, P.; Lavrijsen, W.; Law, A. T.; Laycock, P.; Lazovich, T.; Lazzaroni, M.; Le, B.; Le Dortz, O.; Le Guirriec, E.; Le Quilleuc, E. P.; Leblanc, M.; Lecompte, T.; Ledroit-Guillon, F.; Lee, C. A.; Lee, S. C.; Lee, L.; Lefebvre, B.; Lefebvre, G.; Lefebvre, M.; Legger, F.; Leggett, C.; Lehan, A.; Lehmann Miotto, G.; Lei, X.; Leight, W. A.; Leister, A. G.; Leite, M. A. L.; Leitner, R.; Lellouch, D.; Lemmer, B.; Leney, K. J. C.; Lenz, T.; Lenzi, B.; Leone, R.; Leone, S.; Leonidopoulos, C.; Leontsinis, S.; Lerner, G.; Leroy, C.; Lesage, A. A. J.; Lester, C. G.; Levchenko, M.; Levêque, J.; Levin, D.; Levinson, L. J.; Levy, M.; Lewis, D.; Leyton, M.; Li, B.; Li, C.; Li, H.; Li, L.; Li, L.; Li, Q.; Li, S.; Li, X.; Li, Y.; Liang, Z.; Liberti, B.; Liblong, A.; Lichard, P.; Lie, K.; Liebal, J.; Liebig, W.; Limosani, A.; Lin, S. C.; Lin, T. H.; Lindquist, B. E.; Lionti, A. E.; Lipeles, E.; Lipniacka, A.; Lisovyi, M.; Liss, T. M.; Lister, A.; Litke, A. M.; Liu, B.; Liu, D.; Liu, H.; Liu, H.; Liu, J.; Liu, J. B.; Liu, K.; Liu, L.; Liu, M.; Liu, Y. L.; Liu, Y.; Livan, M.; Lleres, A.; Llorente Merino, J.; Lloyd, S. L.; Lo Sterzo, F.; Lobodzinska, E. M.; Loch, P.; Loebinger, F. K.; Loew, K. M.; Loginov, A.; Lohse, T.; Lohwasser, K.; Lokajicek, M.; Long, B. A.; Long, J. D.; Long, R. E.; Longo, L.; Looper, K. A.; Lopez, J. A.; Lopez Mateos, D.; Lopez Paredes, B.; Lopez Paz, I.; Lopez Solis, A.; Lorenz, J.; Lorenzo Martinez, N.; Losada, M.; Lösel, P. J.; Lou, X.; Lounis, A.; Love, J.; Love, P. A.; Lu, H.; Lu, N.; Lubatti, H. J.; Luci, C.; Lucotte, A.; Luedtke, C.; Luehring, F.; Lukas, W.; Luminari, L.; Lundberg, O.; Lund-Jensen, B.; Luzi, P. M.; Lynn, D.; Lysak, R.; Lytken, E.; Lyubushkin, V.; Ma, H.; Ma, L. L.; Ma, Y.; Maccarrone, G.; Macchiolo, A.; MacDonald, C. M.; Maček, B.; Machado Miguens, J.; Madaffari, D.; Madar, R.; Maddocks, H. J.; Mader, W. F.; Madsen, A.; Maeda, J.; Maeland, S.; Maeno, T.; Maevskiy, A.; Magradze, E.; Mahlstedt, J.; Maiani, C.; Maidantchik, C.; Maier, A. A.; Maier, T.; Maio, A.; Majewski, S.; Makida, Y.; Makovec, N.; Malaescu, B.; Malecki, Pa.; Maleev, V. P.; Malek, F.; Mallik, U.; Malon, D.; Malone, C.; Malone, C.; Maltezos, S.; Malyukov, S.; Mamuzic, J.; Mancini, G.; Mandelli, L.; Mandić, I.; Maneira, J.; Manhaes de Andrade Filho, L.; Manjarres Ramos, J.; Mann, A.; Manousos, A.; Mansoulie, B.; Mansour, J. D.; Mantifel, R.; Mantoani, M.; Manzoni, S.; Mapelli, L.; Marceca, G.; March, L.; Marchiori, G.; Marcisovsky, M.; Marjanovic, M.; Marley, D. E.; Marroquim, F.; Marsden, S. P.; Marshall, Z.; Marti-Garcia, S.; Martin, B.; Martin, T. A.; Martin, V. J.; Martin Dit Latour, B.; Martinez, M.; Martinez Outschoorn, V. I.; Martin-Haugh, S.; Martoiu, V. S.; Martyniuk, A. C.; Marzin, A.; Masetti, L.; Mashimo, T.; Mashinistov, R.; Masik, J.; Maslennikov, A. L.; Massa, I.; Massa, L.; Mastrandrea, P.; Mastroberardino, A.; Masubuchi, T.; Mättig, P.; Mattmann, J.; Maurer, J.; Maxfield, S. J.; Maximov, D. A.; Mazini, R.; Maznas, I.; Mazza, S. M.; Mc Fadden, N. C.; Mc Goldrick, G.; Mc Kee, S. P.; McCarn, A.; McCarthy, R. L.; McCarthy, T. G.; McClymont, L. I.; McDonald, E. F.; McFayden, J. A.; McHedlidze, G.; McMahon, S. J.; McPherson, R. A.; Medinnis, M.; Meehan, S.; Mehlhase, S.; Mehta, A.; Meier, K.; Meineck, C.; Meirose, B.; Melini, D.; Mellado Garcia, B. R.; Melo, M.; Meloni, F.; Menary, S. B.; Meng, L.; Meng, X. T.; Mengarelli, A.; Menke, S.; Meoni, E.; Mergelmeyer, S.; Mermod, P.; Merola, L.; Meroni, C.; Merritt, F. S.; Messina, A.; Metcalfe, J.; Mete, A. S.; Meyer, C.; Meyer, C.; Meyer, J.-P.; Meyer, J.; Meyer Zu Theenhausen, H.; Miano, F.; Middleton, R. P.; Miglioranzi, S.; Mijović, L.; Mikenberg, G.; Mikestikova, M.; Mikuž, M.; Milesi, M.; Milic, A.; Miller, D. W.; Mills, C.; Milov, A.; Milstead, D. A.; Minaenko, A. A.; Minami, Y.; Minashvili, I. A.; Mincer, A. I.; Mindur, B.; Mineev, M.; Minegishi, Y.; Ming, Y.; Mir, L. M.; Mistry, K. P.; Mitani, T.; Mitrevski, J.; Mitsou, V. A.; Miucci, A.; Miyagawa, P. S.; Mizukami, A.; Mjörnmark, J. U.; Mlynarikova, M.; Moa, T.; Mochizuki, K.; Mogg, P.; Mohapatra, S.; Molander, S.; Moles-Valls, R.; Monden, R.; Mondragon, M. C.; Mönig, K.; Monk, J.; Monnier, E.; Montalbano, A.; Montejo Berlingen, J.; Monticelli, F.; Monzani, S.; Moore, R. W.; Morange, N.; Moreno, D.; Moreno Llácer, M.; Morettini, P.; Morgenstern, S.; Mori, D.; Mori, T.; Morii, M.; Morinaga, M.; Morisbak, V.; Moritz, S.; Morley, A. K.; Mornacchi, G.; Morris, J. D.; Mortensen, S. S.; Morvaj, L.; Moschovakos, P.; Mosidze, M.; Moss, H. J.; Moss, J.; Motohashi, K.; Mount, R.; Mountricha, E.; Moyse, E. J. W.; Muanza, S.; Mudd, R. D.; Mueller, F.; Mueller, J.; Mueller, R. S. P.; Mueller, T.; Muenstermann, D.; Mullen, P.; Mullier, G. A.; Munoz Sanchez, F. J.; Murillo Quijada, J. A.; Murray, W. J.; Musheghyan, H.; Muškinja, M.; Myagkov, A. G.; Myska, M.; Nachman, B. P.; Nackenhorst, O.; Nagai, K.; Nagai, R.; Nagano, K.; Nagasaka, Y.; Nagata, K.; Nagel, M.; Nagy, E.; Nairz, A. M.; Nakahama, Y.; Nakamura, K.; Nakamura, T.; Nakano, I.; Naranjo Garcia, R. F.; Narayan, R.; Narrias Villar, D. I.; Naryshkin, I.; Naumann, T.; Navarro, G.; Nayyar, R.; Neal, H. A.; Nechaeva, P. Yu.; Neep, T. J.; Negri, A.; Negrini, M.; Nektarijevic, S.; Nellist, C.; Nelson, A.; Nemecek, S.; Nemethy, P.; Nepomuceno, A. A.; Nessi, M.; Neubauer, M. S.; Neumann, M.; Neves, R. M.; Nevski, P.; Newman, P. R.; Nguyen, D. H.; Nguyen Manh, T.; Nickerson, R. B.; Nicolaidou, R.; Nielsen, J.; Nikiforov, A.; Nikolaenko, V.; Nikolic-Audit, I.; Nikolopoulos, K.; Nilsen, J. K.; Nilsson, P.; Ninomiya, Y.; Nisati, A.; Nisius, R.; Nobe, T.; Nomachi, M.; Nomidis, I.; Nooney, T.; Norberg, S.; Nordberg, M.; Norjoharuddeen, N.; Novgorodova, O.; Nowak, S.; Nozaki, M.; Nozka, L.; Ntekas, K.; Nurse, E.; Nuti, F.; O'Grady, F.; O'Neil, D. C.; O'Rourke, A. A.; O'Shea, V.; Oakham, F. G.; Oberlack, H.; Obermann, T.; Ocariz, J.; Ochi, A.; Ochoa, I.; Ochoa-Ricoux, J. P.; Oda, S.; Odaka, S.; Ogren, H.; Oh, A.; Oh, S. H.; Ohm, C. C.; Ohman, H.; Oide, H.; Okawa, H.; Okumura, Y.; Okuyama, T.; Olariu, A.; Oleiro Seabra, L. F.; Olivares Pino, S. A.; Oliveira Damazio, D.; Olszewski, A.; Olszowska, J.; Onofre, A.; Onogi, K.; Onyisi, P. U. E.; Oreglia, M. J.; Oren, Y.; Orestano, D.; Orlando, N.; Orr, R. S.; Osculati, B.; Ospanov, R.; Otero Y Garzon, G.; Otono, H.; Ouchrif, M.; Ould-Saada, F.; Ouraou, A.; Oussoren, K. P.; Ouyang, Q.; Owen, M.; Owen, R. E.; Ozcan, V. E.; Ozturk, N.; Pachal, K.; Pacheco Pages, A.; Pacheco Rodriguez, L.; Padilla Aranda, C.; Pagan Griso, S.; Paganini, M.; Paige, F.; Pais, P.; Pajchel, K.; Palacino, G.; Palazzo, S.; Palestini, S.; Palka, M.; Pallin, D.; St. Panagiotopoulou, E.; Panagoulias, I.; Pandini, C. E.; Panduro Vazquez, J. G.; Pani, P.; Panitkin, S.; Pantea, D.; Paolozzi, L.; Papadopoulou, Th. D.; Papageorgiou, K.; Paramonov, A.; Paredes Hernandez, D.; Parker, A. J.; Parker, M. A.; Parker, K. A.; Parodi, F.; Parsons, J. A.; Parzefall, U.; Pascuzzi, V. R.; Pasqualucci, E.; Passaggio, S.; Pastore, Fr.; Pásztor, G.; Pataraia, S.; Pater, J. R.; Pauly, T.; Pearce, J.; Pearson, B.; Pedersen, L. E.; Pedersen, M.; Pedraza Lopez, S.; Pedro, R.; Peleganchuk, S. V.; Penc, O.; Peng, C.; Peng, H.; Penwell, J.; Peralva, B. S.; Perego, M. M.; Perepelitsa, D. V.; Perez Codina, E.; Perini, L.; Pernegger, H.; Perrella, S.; Peschke, R.; Peshekhonov, V. D.; Peters, K.; Peters, R. F. Y.; Petersen, B. A.; Petersen, T. C.; Petit, E.; Petridis, A.; Petridou, C.; Petroff, P.; Petrolo, E.; Petrov, M.; Petrucci, F.; Pettersson, N. E.; Peyaud, A.; Pezoa, R.; Phillips, P. W.; Piacquadio, G.; Pianori, E.; Picazio, A.; Piccaro, E.; Piccinini, M.; Pickering, M. A.; Piegaia, R.; Pilcher, J. E.; Pilkington, A. D.; Pin, A. W. J.; Pinamonti, M.; Pinfold, J. L.; Pingel, A.; Pires, S.; Pirumov, H.; Pitt, M.; Plazak, L.; Pleier, M.-A.; Pleskot, V.; Plotnikova, E.; Pluth, D.; Poettgen, R.; Poggioli, L.; Pohl, D.; Polesello, G.; Poley, A.; Policicchio, A.; Polifka, R.; Polini, A.; Pollard, C. S.; Polychronakos, V.; Pommès, K.; Pontecorvo, L.; Pope, B. G.; Popeneciu, G. A.; Poppleton, A.; Pospisil, S.; Potamianos, K.; Potrap, I. N.; Potter, C. J.; Potter, C. T.; Poulard, G.; Poveda, J.; Pozdnyakov, V.; Pozo Astigarraga, M. E.; Pralavorio, P.; Pranko, A.; Prell, S.; Price, D.; Price, L. E.; Primavera, M.; Prince, S.; Prokofiev, K.; Prokoshin, F.; Protopopescu, S.; Proudfoot, J.; Przybycien, M.; Puddu, D.; Purohit, M.; Puzo, P.; Qian, J.; Qin, G.; Qin, Y.; Quadt, A.; Quayle, W. B.; Queitsch-Maitland, M.; Quilty, D.; Raddum, S.; Radeka, V.; Radescu, V.; Radhakrishnan, S. K.; Radloff, P.; Rados, P.; Ragusa, F.; Rahal, G.; Raine, J. A.; Rajagopalan, S.; Rammensee, M.; Rangel-Smith, C.; Ratti, M. G.; Rauch, D. M.; Rauscher, F.; Rave, S.; Ravenscroft, T.; Ravinovich, I.; Raymond, M.; Read, A. L.; Readioff, N. P.; Reale, M.; Rebuzzi, D. M.; Redelbach, A.; Redlinger, G.; Reece, R.; Reed, R. G.; Reeves, K.; Rehnisch, L.; Reichert, J.; Reiss, A.; Rembser, C.; Ren, H.; Rescigno, M.; Resconi, S.; Rezanova, O. L.; Reznicek, P.; Rezvani, R.; Richter, R.; Richter, S.; Richter-Was, E.; Ricken, O.; Ridel, M.; Rieck, P.; Riegel, C. J.; Rieger, J.; Rifki, O.; Rijssenbeek, M.; Rimoldi, A.; Rimoldi, M.; Rinaldi, L.; Ristić, B.; Ritsch, E.; Riu, I.; Rizatdinova, F.; Rizvi, E.; Rizzi, C.; Robertson, S. H.; Robichaud-Veronneau, A.; Robinson, D.; Robinson, J. E. M.; Robson, A.; Roda, C.; Rodina, Y.; Rodriguez Perez, A.; Rodriguez Rodriguez, D.; Roe, S.; Rogan, C. S.; Røhne, O.; Roloff, J.; Romaniouk, A.; Romano, M.; Romano Saez, S. M.; Romero Adam, E.; Rompotis, N.; Ronzani, M.; Roos, L.; Ros, E.; Rosati, S.; Rosbach, K.; Rose, P.; Rosien, N.-A.; Rossetti, V.; Rossi, E.; Rossi, L. P.; Rosten, J. H. N.; Rosten, R.; Rotaru, M.; Roth, I.; Rothberg, J.; Rousseau, D.; Rozanov, A.; Rozen, Y.; Ruan, X.; Rubbo, F.; Rudolph, M. S.; Rühr, F.; Ruiz-Martinez, A.; Rurikova, Z.; Rusakovich, N. A.; Ruschke, A.; Russell, H. L.; Rutherfoord, J. P.; Ruthmann, N.; Ryabov, Y. F.; Rybar, M.; Rybkin, G.; Ryu, S.; Ryzhov, A.; Rzehorz, G. F.; Saavedra, A. F.; Sabato, G.; Sacerdoti, S.; Sadrozinski, H. F.-W.; Sadykov, R.; Safai Tehrani, F.; Saha, P.; Sahinsoy, M.; Saimpert, M.; Saito, T.; Sakamoto, H.; Sakurai, Y.; Salamanna, G.; Salamon, A.; Salazar Loyola, J. E.; Salek, D.; Sales de Bruin, P. H.; Salihagic, D.; Salnikov, A.; Salt, J.; Salvatore, D.; Salvatore, F.; Salvucci, A.; Salzburger, A.; Sammel, D.; Sampsonidis, D.; Sánchez, J.; Sanchez Martinez, V.; Sanchez Pineda, A.; Sandaker, H.; Sandbach, R. L.; Sandhoff, M.; Sandoval, C.; Sankey, D. P. C.; Sannino, M.; Sansoni, A.; Santoni, C.; Santonico, R.; Santos, H.; Santoyo Castillo, I.; Sapp, K.; Sapronov, A.; Saraiva, J. G.; Sarrazin, B.; Sasaki, O.; Sato, K.; Sauvan, E.; Savage, G.; Savard, P.; Savic, N.; Sawyer, C.; Sawyer, L.; Saxon, J.; Sbarra, C.; Sbrizzi, A.; Scanlon, T.; Scannicchio, D. A.; Scarcella, M.; Scarfone, V.; Schaarschmidt, J.; Schacht, P.; Schachtner, B. M.; Schaefer, D.; Schaefer, L.; Schaefer, R.; Schaeffer, J.; Schaepe, S.; Schaetzel, S.; Schäfer, U.; Schaffer, A. C.; Schaile, D.; Schamberger, R. D.; Scharf, V.; Schegelsky, V. A.; Scheirich, D.; Schernau, M.; Schiavi, C.; Schier, S.; Schillo, C.; Schioppa, M.; Schlenker, S.; Schmidt-Sommerfeld, K. R.; Schmieden, K.; Schmitt, C.; Schmitt, S.; Schmitz, S.; Schneider, B.; Schnoor, U.; Schoeffel, L.; Schoening, A.; Schoenrock, B. D.; Schopf, E.; Schott, M.; Schouwenberg, J. F. P.; Schovancova, J.; Schramm, S.; Schreyer, M.; Schuh, N.; Schulte, A.; Schultens, M. J.; Schultz-Coulon, H.-C.; Schulz, H.; Schumacher, M.; Schumm, B. A.; Schune, Ph.; Schwartzman, A.; Schwarz, T. A.; Schweiger, H.; Schwemling, Ph.; Schwienhorst, R.; Schwindling, J.; Schwindt, T.; Sciolla, G.; Scuri, F.; Scutti, F.; Searcy, J.; Seema, P.; Seidel, S. C.; Seiden, A.; Seifert, F.; Seixas, J. M.; Sekhniaidze, G.; Sekhon, K.; Sekula, S. J.; Seliverstov, D. M.; Semprini-Cesari, N.; Serfon, C.; Serin, L.; Serkin, L.; Sessa, M.; Seuster, R.; Severini, H.; Sfiligoj, T.; Sforza, F.; Sfyrla, A.; Shabalina, E.; Shaikh, N. W.; Shan, L. Y.; Shang, R.; Shank, J. T.; Shapiro, M.; Shatalov, P. B.; Shaw, K.; Shaw, S. M.; Shcherbakova, A.; Shehu, C. Y.; Sherwood, P.; Shi, L.; Shimizu, S.; Shimmin, C. O.; Shimojima, M.; Shirabe, S.; Shiyakova, M.; Shmeleva, A.; Shoaleh Saadi, D.; Shochet, M. J.; Shojaii, S.; Shope, D. R.; Shrestha, S.; Shulga, E.; Shupe, M. A.; Sicho, P.; Sickles, A. M.; Sidebo, P. E.; Sideras Haddad, E.; Sidiropoulou, O.; Sidorov, D.; Sidoti, A.; Siegert, F.; Sijacki, Dj.; Silva, J.; Silverstein, S. B.; Simak, V.; Simic, Lj.; Simion, S.; Simioni, E.; Simmons, B.; Simon, D.; Simon, M.; Sinervo, P.; Sinev, N. B.; Sioli, M.; Siragusa, G.; Sivoklokov, S. Yu.; Sjölin, J.; Skinner, M. B.; Skottowe, H. P.; Skubic, P.; Slater, M.; Slavicek, T.; Slawinska, M.; Sliwa, K.; Slovak, R.; Smakhtin, V.; Smart, B. H.; Smestad, L.; Smiesko, J.; Smirnov, S. Yu.; Smirnov, Y.; Smirnova, L. N.; Smirnova, O.; Smith, J. W.; Smith, M. N. K.; Smith, R. W.; Smizanska, M.; Smolek, K.; Snesarev, A. A.; Snyder, I. M.; Snyder, S.; Sobie, R.; Socher, F.; Soffer, A.; Soh, D. A.; Sokhrannyi, G.; Solans Sanchez, C. A.; Solar, M.; Soldatov, E. Yu.; Soldevila, U.; Solodkov, A. A.; Soloshenko, A.; Solovyanov, O. V.; Solovyev, V.; Sommer, P.; Son, H.; Song, H. Y.; Sood, A.; Sopczak, A.; Sopko, V.; Sorin, V.; Sosa, D.; Sotiropoulou, C. L.; Soualah, R.; Soukharev, A. M.; South, D.; Sowden, B. C.; Spagnolo, S.; Spalla, M.; Spangenberg, M.; Spanò, F.; Sperlich, D.; Spettel, F.; Spighi, R.; Spigo, G.; Spiller, L. A.; Spousta, M.; St. Denis, R. D.; Stabile, A.; Stamen, R.; Stamm, S.; Stanecka, E.; Stanek, R. W.; Stanescu, C.; Stanescu-Bellu, M.; Stanitzki, M. M.; Stapnes, S.; Starchenko, E. A.; Stark, G. H.; Stark, J.; Staroba, P.; Starovoitov, P.; Stärz, S.; Staszewski, R.; Steinberg, P.; Stelzer, B.; Stelzer, H. J.; Stelzer-Chilton, O.; Stenzel, H.; Stewart, G. A.; Stillings, J. A.; Stockton, M. C.; Stoebe, M.; Stoicea, G.; Stolte, P.; Stonjek, S.; Stradling, A. R.; Straessner, A.; Stramaglia, M. E.; Strandberg, J.; Strandberg, S.; Strandlie, A.; Strauss, M.; Strizenec, P.; Ströhmer, R.; Strom, D. M.; Stroynowski, R.; Strubig, A.; Stucci, S. A.; Stugu, B.; Styles, N. A.; Su, D.; Su, J.; Suchek, S.; Sugaya, Y.; Suk, M.; Sulin, V. V.; Sultansoy, S.; Sumida, T.; Sun, S.; Sun, X.; Sundermann, J. E.; Suruliz, K.; Suster, C. J. E.; Sutton, M. R.; Suzuki, S.; Svatos, M.; Swiatlowski, M.; Swift, S. P.; Sykora, I.; Sykora, T.; Ta, D.; Taccini, C.; Tackmann, K.; Taenzer, J.; Taffard, A.; Tafirout, R.; Taiblum, N.; Takai, H.; Takashima, R.; Takeshita, T.; Takubo, Y.; Talby, M.; Talyshev, A. A.; Tan, K. G.; Tanaka, J.; Tanaka, M.; Tanaka, R.; Tanaka, S.; Tanioka, R.; Tannenwald, B. B.; Tapia Araya, S.; Tapprogge, S.; Tarem, S.; Tartarelli, G. F.; Tas, P.; Tasevsky, M.; Tashiro, T.; Tassi, E.; Tavares Delgado, A.; Tayalati, Y.; Taylor, A. C.; Taylor, G. N.; Taylor, P. T. E.; Taylor, W.; Teischinger, F. A.; Teixeira-Dias, P.; Temming, K. K.; Temple, D.; Ten Kate, H.; Teng, P. K.; Teoh, J. J.; Tepel, F.; Terada, S.; Terashi, K.; Terron, J.; Terzo, S.; Testa, M.; Teuscher, R. J.; Theveneaux-Pelzer, T.; Thomas, J. P.; Thomas-Wilsker, J.; Thompson, P. D.; Thompson, A. S.; Thomsen, L. A.; Thomson, E.; Tibbetts, M. J.; Ticse Torres, R. E.; Tikhomirov, V. O.; Tikhonov, Yu. A.; Timoshenko, S.; Tipton, P.; Tisserant, S.; Todome, K.; Todorov, T.; Todorova-Nova, S.; Tojo, J.; Tokár, S.; Tokushuku, K.; Tolley, E.; Tomlinson, L.; Tomoto, M.; Tompkins, L.; Toms, K.; Tong, B.; Tornambe, P.; Torrence, E.; Torres, H.; Torró Pastor, E.; Toth, J.; Touchard, F.; Tovey, D. R.; Trefzger, T.; Tricoli, A.; Trigger, I. M.; Trincaz-Duvoid, S.; Tripiana, M. F.; Trischuk, W.; Trocmé, B.; Trofymov, A.; Troncon, C.; Trottier-McDonald, M.; Trovatelli, M.; Truong, L.; Trzebinski, M.; Trzupek, A.; Tseng, J. C.-L.; Tsiareshka, P. V.; Tsipolitis, G.; Tsirintanis, N.; Tsiskaridze, S.; Tsiskaridze, V.; Tskhadadze, E. G.; Tsui, K. M.; Tsukerman, I. I.; Tsulaia, V.; Tsuno, S.; Tsybychev, D.; Tu, Y.; Tudorache, A.; Tudorache, V.; Tulbure, T. T.; Tuna, A. N.; Tupputi, S. A.; Turchikhin, S.; Turgeman, D.; Turk Cakir, I.; Turra, R.; Tuts, P. M.; Ucchielli, G.; Ueda, I.; Ughetto, M.; Ukegawa, F.; Unal, G.; Undrus, A.; Unel, G.; Ungaro, F. C.; Unno, Y.; Unverdorben, C.; Urban, J.; Urquijo, P.; Urrejola, P.; Usai, G.; Usui, J.; Vacavant, L.; Vacek, V.; Vachon, B.; Valderanis, C.; Valdes Santurio, E.; Valencic, N.; Valentinetti, S.; Valero, A.; Valery, L.; Valkar, S.; Valls Ferrer, J. A.; van den Wollenberg, W.; van der Deijl, P. C.; van der Graaf, H.; van Eldik, N.; van Gemmeren, P.; van Nieuwkoop, J.; van Vulpen, I.; van Woerden, M. C.; Vanadia, M.; Vandelli, W.; Vanguri, R.; Vaniachine, A.; Vankov, P.; Vardanyan, G.; Vari, R.; Varnes, E. W.; Varol, T.; Varouchas, D.; Vartapetian, A.; Varvell, K. E.; Vasquez, J. G.; Vasquez, G. A.; Vazeille, F.; Vazquez Schroeder, T.; Veatch, J.; Veeraraghavan, V.; Veloce, L. M.; Veloso, F.; Veneziano, S.; Ventura, A.; Venturi, M.; Venturi, N.; Venturini, A.; Vercesi, V.; Verducci, M.; Verkerke, W.; Vermeulen, J. C.; Vest, A.; Vetterli, M. C.; Viazlo, O.; Vichou, I.; Vickey, T.; Vickey Boeriu, O. E.; Viehhauser, G. H. A.; Viel, S.; Vigani, L.; Villa, M.; Villaplana Perez, M.; Vilucchi, E.; Vincter, M. G.; Vinogradov, V. B.; Vittori, C.; Vivarelli, I.; Vlachos, S.; Vlasak, M.; Vogel, M.; Vokac, P.; Volpi, G.; Volpi, M.; von der Schmitt, H.; von Toerne, E.; Vorobel, V.; Vorobev, K.; Vos, M.; Voss, R.; Vossebeld, J. H.; Vranjes, N.; Vranjes Milosavljevic, M.; Vrba, V.; Vreeswijk, M.; Vuillermet, R.; Vukotic, I.; Wagner, P.; Wagner, W.; Wahlberg, H.; Wahrmund, S.; Wakabayashi, J.; Walder, J.; Walker, R.; Walkowiak, W.; Wallangen, V.; Wang, C.; Wang, C.; Wang, F.; Wang, H.; Wang, H.; Wang, J.; Wang, J.; Wang, K.; Wang, R.; Wang, S. M.; Wang, T.; Wang, W.; Wanotayaroj, C.; Warburton, A.; Ward, C. P.; Wardrope, D. R.; Washbrook, A.; Watkins, P. M.; Watson, A. T.; Watson, M. F.; Watts, G.; Watts, S.; Waugh, B. M.; Webb, S.; Weber, M. S.; Weber, S. W.; Weber, S. A.; Webster, J. S.; Weidberg, A. R.; Weinert, B.; Weingarten, J.; Weiser, C.; Weits, H.; Wells, P. S.; Wenaus, T.; Wengler, T.; Wenig, S.; Wermes, N.; Werner, M. D.; Werner, P.; Wessels, M.; Wetter, J.; Whalen, K.; Whallon, N. L.; Wharton, A. M.; White, A.; White, M. J.; White, R.; Whiteson, D.; Wickens, F. J.; Wiedenmann, W.; Wielers, M.; Wiglesworth, C.; Wiik-Fuchs, L. A. M.; Wildauer, A.; Wilk, F.; Wilkens, H. G.; Williams, H. H.; Williams, S.; Willis, C.; Willocq, S.; Wilson, J. A.; Wingerter-Seez, I.; Winklmeier, F.; Winston, O. J.; Winter, B. T.; Wittgen, M.; Wolf, T. M. H.; Wolff, R.; Wolter, M. W.; Wolters, H.; Worm, S. D.; Wosiek, B. K.; Wotschack, J.; Woudstra, M. J.; Wozniak, K. W.; Wu, M.; Wu, M.; Wu, S. L.; Wu, X.; Wu, Y.; Wyatt, T. R.; Wynne, B. M.; Xella, S.; Xi, Z.; Xu, D.; Xu, L.; Yabsley, B.; Yacoob, S.; Yamaguchi, D.; Yamaguchi, Y.; Yamamoto, A.; Yamamoto, S.; Yamanaka, T.; Yamauchi, K.; Yamazaki, Y.; Yan, Z.; Yang, H.; Yang, H.; Yang, Y.; Yang, Z.; Yao, W.-M.; Yap, Y. C.; Yasu, Y.; Yatsenko, E.; Yau Wong, K. H.; Ye, J.; Ye, S.; Yeletskikh, I.; Yildirim, E.; Yorita, K.; Yoshida, R.; Yoshihara, K.; Young, C.; Young, C. J. S.; Youssef, S.; Yu, D. R.; Yu, J.; Yu, J. M.; Yu, J.; Yuan, L.; Yuen, S. P. Y.; Yusuff, I.; Zabinski, B.; Zacharis, G.; Zaidan, R.; Zaitsev, A. M.; Zakharchuk, N.; Zalieckas, J.; Zaman, A.; Zambito, S.; Zanello, L.; Zanzi, D.; Zeitnitz, C.; Zeman, M.; Zemla, A.; Zeng, J. C.; Zeng, Q.; Zenin, O.; Ženiš, T.; Zerwas, D.; Zhang, D.; Zhang, F.; Zhang, G.; Zhang, H.; Zhang, J.; Zhang, L.; Zhang, L.; Zhang, M.; Zhang, R.; Zhang, R.; Zhang, X.; Zhang, Z.; Zhao, X.; Zhao, Y.; Zhao, Z.; Zhemchugov, A.; Zhong, J.; Zhou, B.; Zhou, C.; Zhou, L.; Zhou, L.; Zhou, M.; Zhou, N.; Zhu, C. G.; Zhu, H.; Zhu, J.; Zhu, Y.; Zhuang, X.; Zhukov, K.; Zibell, A.; Zieminska, D.; Zimine, N. I.; Zimmermann, C.; Zimmermann, S.; Zinonos, Z.; Zinser, M.; Ziolkowski, M.; Živković, L.; Zobernig, G.; Zoccoli, A.; Zur Nedden, M.; Zwalinski, L.; Atlas Collaboration

2017-10-01

The production of opposite-charge W-boson pairs in proton-proton collisions at √{ s} = 13 TeV is measured using data corresponding to 3.16 fb-1 of integrated luminosity collected by the ATLAS detector at the CERN Large Hadron Collider in 2015. Candidate W-boson pairs are selected by identifying their leptonic decays into an electron, a muon and neutrinos. Events with reconstructed jets are not included in the candidate event sample. The cross-section measurement is performed in a fiducial phase space close to the experimental acceptance and is compared to theoretical predictions. Agreement is found between the measurement and the most accurate calculations available.

News from the NA61/SHINE experiment

NASA Astrophysics Data System (ADS)

Šuša, Tatjana

2018-02-01

The main goals of the NA61/SHINE experiment at the CERN SPS are the search for the critical point of strongly interacting matter and the study of the properties of the onset of deconfinement. These aims are pursued by performing a two-dimensional scan of the phase diagram of strongly interacting matter by varying the momentum and size of the colliding nuclei. This contribution summarises the latest results from the NA61/SHINE experiment, in particular, new results on spectra and yields of ϕ meson in p+p interactions at 40, 80 and 158 GeV/c and K+ and K- production in central Be+Be collisions at mid-rapidity. In addition, results on system size dependence of particle yield ratios and fluctuations are presented.

Six-quark decays of the Higgs boson in supersymmetry with R-parity violation.

PubMed

Carpenter, Linda M; Kaplan, David E; Rhee, Eun-Jung

2007-11-23

Both electroweak precision measurements and simple supersymmetric extensions of the standard model prefer a mass of the Higgs boson less than the experimental lower limit (on a standard-model-like Higgs boson) of 114 GeV. We show that supersymmetric models with R parity violation and baryon-number violation have a significant range of parameter space in which the Higgs boson dominantly decays to six jets. These decays are much more weakly constrained by current CERN LEP analyses and would allow for a Higgs boson mass near that of the Z. In general, lighter scalar quark and other superpartner masses are allowed. The Higgs boson would potentially be discovered at hadron colliders via the appearance of new displaced vertices.

Simulations of the failure scenarios of the crab cavities for the nominal scheme of the LHC

NASA Astrophysics Data System (ADS)

Yee, B.; Calaga, R.; Zimmermann, F.; Lopez, R.

2012-02-01

The Crab Cavity (CC) represents a possible solution to the problem of the reduction in luminosity due to the impact angle of two colliding beams. The CC is a Radio Frequency (RF) superconducting cavity which applies a transversal kick into a bunch of particles producing a rotation in order to have a head-on collision to improve the luminosity. For this reason people at the Beams Department-Accelerators & Beams Physics of CERN (BE-ABP) have studied the implementation of the CC scheme at the LHC. It is essential to study the failure scenarios and the damage that can be produced to the lattice devices. We have performed simulations of these failures for the nominal scheme.

The upgrade of the CMS hadron calorimeter with silicon photomultipliers

DOE PAGES

Strobbe, N.

2017-01-26

The upgrade of the hadron calorimeter of the CMS experiment at the CERN Large Hadron Collider is currently underway. The endcap sections will be upgraded in the winter of 2016–2017 and the barrel sections during the second LHC long shutdown in 2019. The existing photosensors will be replaced with about 16 000 new silicon photomultipliers (SiPMs), resulting in the first large installation of SiPMs in a radiation environment. All associated front-end electronics will also be upgraded. Here, this paper discusses the motivation for the upgrade and provides a description 17 of the new system, including the SiPMs with associated controlmore » electronics and the front-end readout cards.« less

"Infinitos"

NASA Astrophysics Data System (ADS)

1994-04-01

On Friday, 22 April 1994, a new science exhibition ``Infinitos", arranged jointly by Lisboa'94, CERN and ESO, will open at the Museu de Electricidade on the waterfront of Lisbon, the capital of Portugal. In a series of spectacular displays, it illustrates man's current understanding of how the Universe works - from the tiniest structures of matter to the most far flung galaxies. On this day, it will be inaugurated by the President of Lisboa'94, Prof. Vitor Constancio, the Portuguese Science Minister, Prof. L. Valente de Oliveira, Prof. C. Llewellyn Smith, Director General of CERN [2] and Dr. P. Creola, President of ESO Council. This exhibition is part of a rich cultural programme taking place at Lisbon during 1994 in the frame of ``Lisboa 94 - European City of Culture", after which it will travel to major cities around Europe. The frontiers of our knowledge push into inner space - the structure of the smallest components of matter - and into outer space - the dramatic phenomena of distant galaxies. Two of Europe's leading science organisations are playing a crucial role in this great human adventure. The European Laboratory for Particle Physics, CERN, operates the mighty accelerators and colliding beam machines to penetrate deep into matter and recreate the conditions which prevailed in the Universe a tiny fraction of a second after the Big Bang. The European Southern Observatory, ESO, operates the largest optical observatory in the world with a range of advanced telescopes searching the sky to study the evolution and content of our Universe. The ``Infinitos'' exhibition uses many modern exhibition techniques, including sophisticated audio-visual presentations and interactive video programmes. Visitors enter through a gallery of portraits of the most celebrated scientists from the 16th to 20th centuries and an exhibition of art inspired by scientific research. After passing a cosmic ray detector showing the streams of particles which pour down constantly from outer space, visitors continue into a central area where they are confronted with the essential questions of astro- and particle physics, f.inst. ``What is the Universe made of?'', ``How was the Universe created?'', ``What is in the sky?'', ``What is Dark Matter?'', ``Where does the stuff in our bodies come from?'', and ``Are we alone in the Universe?'' A central theme of this display is ``What we don't know''. In the second part of the exhibition visitors are shown the instruments and techniques used in today's big science research which will help to provide the answers. There are special displays on Europe's future large research projects such as the Large Hadron Collider (LHC) at CERN, which will bring protons into head-on collision at higher energies (14 TeV) than ever before to allow scientists to penetrate still further into the structure of matter and recreate the conditions prevailing in the Universe just 10-12 seconds after the "Big Bang" when the temperature was 10^16 degrees. Another highlight is a large interactive model of ESO's Very Large Telescope (VLT), the world's most ambitious optical telescope project, now under construction. The telescope's unequalled potential for exciting astronomical observations at the outer reaches of the Universe is clearly explained. Special emphasis is given to the contribution of Portuguese research institutes to the work of CERN and ESO, and particle physicists and astronomers from Portugal will be present at the exhibition to talk to visitors about their work. This exhibition will remain open until 12 June 1994 and will be a major attraction, also to the many tourists visiting this year's European City of Culture. 1. This is a joint Press Release of Lisboa'94, CERN and ESO. 2. CERN, the European Laboratory for Particle Physics, has its headquarters in Geneva. At present, its Member States are Austria, Belgium, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Italy, Netherlands, Norway, Poland, Portugal, the Slovak Republic, Spain, Sweden, Switzerland and the United Kingdom. Israel, the Russian Federation, Turkey, Yugoslavia (status suspended after UN embargo, June 1992), the European Commission and Unesco have observer status.

Summary of experimental studies, at CERN, on a positron source using crystal effects

NASA Astrophysics Data System (ADS)

Artru, X.; Baier, V.; Beloborodov, K.; Bogdanov, A.; Bukin, A.; Burdin, S.; Chehab, R.; Chevallier, M.; Cizeron, R.; Dauvergne, D.; Dimova, T.; Druzhinin, V.; Dubrovin, M.; Gatignon, L.; Golubev, V.; Jejcic, A.; Keppler, P.; Kirsch, R.; Kulibaba, V.; Lautesse, Ph.; Major, J.; Poizat, J.-C.; Potylitsin, A.; Remillieux, J.; Serednyakov, S.; Shary, V.; Strakhovenko, V.; Sylvia, C.

2005-11-01

A new kind of positron sources for future linear colliders, where the converter is an aligned tungsten crystal, oriented on the <1 1 1>-axis, has been studied at CERN in the WA103 experiment with tertiary electron beams from the SPS. In such sources the photons resulting from channeling radiation and coherent bremsstrahlung create the e+e- pairs. Electron beams, of 6 and 10 GeV, were impinging on different kinds of targets: a 4 mm thick crystal, a 8 mm thick crystal and a compound target made of 4 mm crystal followed by 4 mm amorphous disk. An amorphous tungsten target 20 mm thick was also used for the sake of comparison with the 8 mm crystal and to check the ability of the detection system to provide the correct track reconstruction. The charged particles coming out from the target were detected in a drift chamber immersed partially in a magnetic field. The reconstruction of the particle trajectories provided the energy and angular spectrum of the positrons in a rather wide energy range (up to 150 MeV) and angular domain (up to 30°). The experimental approach presented in this article provides a full description of this kind of source. A presentation of the measured positron distribution in momentum space (longitudinal versus transverse) is given to allow an easy determination of the available yield for a given momentum acceptance. Results on photons, measured downstream of the positron detector, are also presented. A significant enhancement of photon and positron production is clearly observed. This enhancement, for a 10 GeV incident beam, is of 4 for the 4 mm thick crystal and larger than 2 for the 8 mm thick crystal. Another important result concerns the validation of the simulations for the crystals, for which a quite good agreement was met between the simulations and the experiment, for positrons as well as for photons. These results are presented after a short presentation of the experimental setup and of the track reconstruction procedure.

Accelerator Science: Circular vs. Linear

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lincoln, Don

Particle accelerator are scientific instruments that allow scientists to collide particles together at incredible energies to study the secrets of the universe. However, there are many manners in which particle accelerators can be constructed. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of circular and linear accelerators.

Physics Goals for the Planned Next Linear Collider Engineering Test Facility

NASA Astrophysics Data System (ADS)

Raubenheimer, T. O.

2001-10-01

The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well as of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.

RF pulse shape control in the compact linear collider test facility

NASA Astrophysics Data System (ADS)

Kononenko, Oleksiy; Corsini, Roberto

2018-07-01

The Compact Linear Collider (CLIC) is a study for an electron-positron machine aiming at accelerating and colliding particles at the next energy frontier. The CLIC concept is based on the novel two-beam acceleration scheme, where a high-current low-energy drive beam generates RF in series of power extraction and transfer structures accelerating the low-current main beam. To compensate for the transient beam-loading and meet the energy spread specification requirements for the main linac, the RF pulse shape must be carefully optimized. This was recently modelled by varying the drive beam phase switch times in the sub-harmonic buncher so that, when combined, the drive beam modulation translates into the required voltage modulation of the accelerating pulse. In this paper, the control over the RF pulse shape with the phase switches, that is crucial for the success of the developed compensation model, is studied. The results on the experimental verification of this control method are presented and a good agreement with the numerical predictions is demonstrated. Implications for the CLIC beam-loading compensation model are also discussed.

Improved Monte Carlo Glauber predictions at present and future nuclear colliders

NASA Astrophysics Data System (ADS)

Loizides, Constantin; Kamin, Jason; d'Enterria, David

2018-05-01

We present the results of an improved Monte Carlo Glauber (MCG) model of relevance for collisions involving nuclei at center-of-mass energies of the BNL Relativistic Heavy Ion Collider (√{sNN}=0.2 TeV), CERN Large Hadron Collider (LHC) (√{sNN}=2.76 -8.8 TeV ), and proposed future hadron colliders (√{sNN}≈10 -63 TeV). The inelastic p p cross sections as a function of √{sNN} are obtained from a precise data-driven parametrization that exploits the many available measurements at LHC collision energies. We describe the nuclear density of a lead nucleus with two separated two-parameter Fermi distributions for protons and neutrons to account for their different densities close to the nuclear periphery. Furthermore, we model the nucleon degrees of freedom inside the nucleus through a lattice with a minimum nodal separation, combined with a "recentering and reweighting" procedure, that overcomes some limitations of previous MCG approaches. The nuclear overlap function, number of participant nucleons and binary nucleon-nucleon collisions, participant eccentricity and triangularity, overlap area, and average path length are presented in intervals of percentile centrality for lead-lead (PbPb) and proton-lead (p Pb ) collisions at all collision energies. We demonstrate for collisions at √{sNN}=5.02 TeV that the central values of the Glauber quantities change by up to 7% in a few bins of reaction centrality, due to the improvements implemented, though typically they remain within the previously assigned systematic uncertainties, while their new associated uncertainties are generally smaller (mostly below 5%) at all centralities than for earlier calculations. Tables for all quantities versus centrality at present and foreseen collision energies involving Pb nuclei, as well as for collisions of XeXe at √{sNN}=5.44 TeV , and AuAu and CuCu at √{sNN}=0.2 TeV , are provided. The source code for the improved Monte Carlo Glauber model is made publicly available.

Gravitational mass of relativistic matter and antimatter

DOE PAGES

Kalaydzhyan, Tigran

2015-10-13

The universality of free fall, the weak equivalence principle (WEP), is a cornerstone of the general theory of relativity, the most precise theory of gravity confirmed in all experiments up to date. The WEP states the equivalence of the inertial, m, and gravitational, m g, masses and was tested in numerous occasions with normal matter at relatively low energies. However, there is no confirmation for the matter and antimatter at high energies. For the antimatter the situation is even less clear – current direct observations of trapped antihydrogen suggest the limits -65 < m g/m <110 not excluding the so-calledmore » antigravity phenomenon, i.e. repulsion of the antimatter by Earth. Here we demonstrate an indirect bound 0.96 < m g/m < 1.04 on the gravitational mass of relativistic electrons and positrons coming from the absence of the vacuum Cherenkov radiation at the Large Electron–Positron Collider (LEP) and stability of photons at the Tevatron collider in presence of the annual variations of the solar gravitational potential. Our result clearly rules out the speculated antigravity. By considering the absolute potential of the Local Supercluster (LS), we also predict the bounds 1 -4 ×10 -7 < m g/m <1 +2 ×10 -7 for an electron and positron. Lastly, we comment on a possibility of performing complementary tests at the future International Linear Collider (ILC) and Compact Linear Collider (CLIC).« less

Gravitational mass of relativistic matter and antimatter

NASA Astrophysics Data System (ADS)

Kalaydzhyan, Tigran

2015-12-01

The universality of free fall, the weak equivalence principle (WEP), is a cornerstone of the general theory of relativity, the most precise theory of gravity confirmed in all experiments up to date. The WEP states the equivalence of the inertial, m, and gravitational, mg, masses and was tested in numerous occasions with normal matter at relatively low energies. However, there is no confirmation for the matter and antimatter at high energies. For the antimatter the situation is even less clear - current direct observations of trapped antihydrogen suggest the limits - 65

Progress on the Development of the Nb 3Sn 11T Dipole for the High Luminosity Upgrade of LHC

DOE PAGES

Savary, Frederic; Bajko, Marta; Bordini, Bernardo; ...

2017-02-08

The high-luminosity large hadron collider (LHC) project at CERN entered into the production phase in October 2015 after the completion of the design study phase. In the meantime, the development of the 11 T dipole needed for the upgrade of the collimation system of the machine made significant progress with very good performance of the first two-in-one magnet model of 2-m length made at CERN. The 11 T dipole, which is more powerful than the current main dipoles of LHC, can be made shorter with an equivalent integrated field. This will allow creating space for the installation of additional collimatorsmore » in specific locations of the dispersion suppressor regions. Following tests carried out during heavy ions runs of LHC in the end of 2015, and a more recent review of the project budget, the installation plan for the 11 T dipole was revised. Consequently, one 11 T dipole full assembly containing two 11 T dipoles of 5.5-m length will be installed on either side of interaction point 7. These two units shall be installed during the long shutdown 2 in years 2019-2020. After a brief reminder on the design features of the magnet, this paper describes the current status of the development activities, in particular the short model programme and the construction of the first full scale prototype at CERN. Finally, critical operations such as the reaction treatment and the coil impregnation are discussed, the quench performance tests results of the two-in-one model are reviewed and finally, the plan toward the production for the long shut down 2 is described.« less

Underground neutrino detectors for particle and astroparticle Science: The Giant Liquid Argon Charge Imaging ExpeRiment (GLACIER)

NASA Astrophysics Data System (ADS)

Rubbia, André

2009-06-01

The current focus of the CERN program is the Large Hadron Collider (LHC), however, CERN is engaged in long baseline neutrino physics with the CNGS project and supports T2K as recognized CERN RE13, and for good reasons: a number of observed phenomena in high-energy physics and cosmology lack their resolution within the Standard Model of particle physics; these puzzles include the origin of neutrino masses, CP-violation in the leptonic sector, and baryon asymmetry of the Universe. They will only partially be addressed at LHC. A positive measurement of sin2 2θ13 > 0.01 would certainly give a tremendous boost to neutrino physics by opening the possibility to study CP violation in the lepton sector and the determination of the neutrino mass hierarchy with upgraded conventional super-beams. These experiments (so called 'Phase II') require, in addition to an upgraded beam power, next generation very massive neutrino detectors with excellent energy resolution and high detection efficiency in a wide neutrino energy range, to cover 1st and 2nd oscillation maxima, and excellent particle identification and p0 background suppression. Two generations of large water Cherenkov detectors at Kamioka (Kamiokande and Super-Kamiokande) have been extremely successful. And there are good reasons to consider a third generation water Cherenkov detector with an order of magnitude larger mass than Super-Kamiokande for both non-accelerator (proton decay, supernovae,...) and accelerator-based physics. On the other hand, a very massive underground liquid Argon detector of about 100 kton could represent a credible alternative for the precision measurements of 'Phase II' and aim at significantly new results in neutrino astroparticle and non-accelerator-based particle physics (e.g. proton decay).

Same sign dimuon search for heavy majorana mass neutrinos at the CMS experiment at CERN and design studies of a quartz plate calorimeter prototype

DOE Office of Scientific and Technical Information (OSTI.GOV)

Clarida, Warren James

2012-12-01

This paper consists of two studies: the results of a search for heavy Majorana neutrinos (N) using an event signature defined by two like-sign charged muons and two jets, and the results from studies of a prototype quartz plate calorimeter. The data in the Majorana search correspond to an integrated luminosity of 5.0 fbmore » $$^{−1}$$ of pp collisions at a centre-of-mass energy of 7 TeV collected with the CMS detector at the Large Hadron Collider. No excess of events are observed beyond the expected standard model background and therefore upper limits are set on the square of the mixing element, $$|V_{\\mu N} |$$as a function of Majorana neutrino mass. These are the first direct upper limits on the heavy Majorana-neutrino mixing for m$$_N$$ > 90 GeV . The second part of this thesis is the results of performance tests of a 20-layer quartz plate calorimeter prototype. The calorimeter prototype was tested at the CERN H2 area in hadronic and electromagnetic configurations, at various en ergies of pion and electron beams. The beam test and simulation results of this prototype are reported.« less

EFQPSK Versus CERN: A Comparative Study

NASA Technical Reports Server (NTRS)

Borah, Deva K.; Horan, Stephen

2001-01-01

This report presents a comparative study on Enhanced Feher's Quadrature Phase Shift Keying (EFQPSK) and Constrained Envelope Root Nyquist (CERN) techniques. These two techniques have been developed in recent times to provide high spectral and power efficiencies under nonlinear amplifier environment. The purpose of this study is to gain insights into these techniques and to help system planners and designers with an appropriate set of guidelines for using these techniques. The comparative study presented in this report relies on effective simulation models and procedures. Therefore, a significant part of this report is devoted to understanding the mathematical and simulation models of the techniques and their set-up procedures. In particular, mathematical models of EFQPSK and CERN, effects of the sampling rate in discrete time signal representation, and modeling of nonlinear amplifiers and predistorters have been considered in detail. The results of this study show that both EFQPSK and CERN signals provide spectrally efficient communications compared to filtered conventional linear modulation techniques when a nonlinear power amplifier is used. However, there are important differences. The spectral efficiency of CERN signals, with a small amount of input backoff, is significantly better than that of EFQPSK signals if the nonlinear amplifier is an ideal clipper. However, to achieve such spectral efficiencies with a practical nonlinear amplifier, CERN processing requires a predistorter which effectively translates the amplifier's characteristics close to those of an ideal clipper. Thus, the spectral performance of CERN signals strongly depends on the predistorter. EFQPSK signals, on the other hand, do not need such predistorters since their spectra are almost unaffected by the nonlinear amplifier, Ibis report discusses several receiver structures for EFQPSK signals. It is observed that optimal receiver structures can be realized for both coded and uncoded EFQPSK signals with not too much increase in computational complexity. When a nonlinear amplifier is used, the bit error rate (BER) performance of the CERN signals with a matched filter receiver is found to be more than one decibel (dB) worse compared to the bit error performance of EFQPSK signals. Although channel coding is found to provide BER performance improvement for both EFQPSK and CERN signals, the performance of EFQPSK signals remains better than that of CERN. Optimal receiver structures for CERN signals with nonlinear equalization is left as a possible future work. Based on the numerical results, it is concluded that, in nonlinear channels, CERN processing leads towards better bandwidth efficiency with a compromise in power efficiency. Hence for bandwidth efficient communications needs, CERN is a good solution provided effective adaptive predistorters can be realized. On the other hand, EFQPSK signals provide a good power efficient solution with a compromise in band width efficiency.

Accelerator Science: Circular vs. Linear

ScienceCinema

Lincoln, Don

2018-06-12

Particle accelerator are scientific instruments that allow scientists to collide particles together at incredible energies to study the secrets of the universe. However, there are many manners in which particle accelerators can be constructed. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of circular and linear accelerators.

DIRAC in Large Particle Physics Experiments

NASA Astrophysics Data System (ADS)

Stagni, F.; Tsaregorodtsev, A.; Arrabito, L.; Sailer, A.; Hara, T.; Zhang, X.; Consortium, DIRAC

2017-10-01

The DIRAC project is developing interware to build and operate distributed computing systems. It provides a development framework and a rich set of services for both Workload and Data Management tasks of large scientific communities. A number of High Energy Physics and Astrophysics collaborations have adopted DIRAC as the base for their computing models. DIRAC was initially developed for the LHCb experiment at LHC, CERN. Later, the Belle II, BES III and CTA experiments as well as the linear collider detector collaborations started using DIRAC for their computing systems. Some of the experiments built their DIRAC-based systems from scratch, others migrated from previous solutions, ad-hoc or based on different middlewares. Adaptation of DIRAC for a particular experiment was enabled through the creation of extensions to meet their specific requirements. Each experiment has a heterogeneous set of computing and storage resources at their disposal that were aggregated through DIRAC into a coherent pool. Users from different experiments can interact with the system in different ways depending on their specific tasks, expertise level and previous experience using command line tools, python APIs or Web Portals. In this contribution we will summarize the experience of using DIRAC in particle physics collaborations. The problems of migration to DIRAC from previous systems and their solutions will be presented. An overview of specific DIRAC extensions will be given. We hope that this review will be useful for experiments considering an update, or for those designing their computing models.

Linear beam dynamics and ampere class superconducting RF cavities at RHIC

NASA Astrophysics Data System (ADS)

Calaga, Rama R.

The Relativistic Heavy Ion Collider (RHIC) is a hadron collider designed to collide a range of ions from protons to gold. RHIC operations began in 2000 and has successfully completed five physics runs with several species including gold, deuteron, copper, and polarized protons. Linear optics and coupling are fundamental issues affecting the collider performance. Measurement and correction of optics and coupling are important to maximize the luminosity and sustain stable operation. A numerical approach, first developed at SLAC, was implemented to measure linear optics from coherent betatron oscillations generated by ac dipoles and recorded at multiple beam position monitors (BPMs) distributed around the collider. The approach is extended to a fully coupled 2D case and equivalence relationships between Hamiltonian and matrix formalisms are derived. Detailed measurements of the transverse coupling terms are carried out at RHIC and correction strategies are applied to compensate coupling both locally and globally. A statistical approach to determine BPM reliability and performance over the past three runs and future improvements also discussed. Aiming at a ten-fold increase in the average heavy-ion luminosity, electron cooling is the enabling technology for the next luminosity upgrade (RHIC II). Cooling gold ion beams at 100 GeV/nucleon requires an electron beam of approximately 54 MeV and a high average current in the range of 50-200 mA. All existing e-Coolers are based on low energy DC accelerators. The only viable option to generate high current, high energy, low emittance CW electron beam is through a superconducting energy-recovery linac (SC-ERL). In this option, an electron beam from a superconducting injector gun is accelerated using a high gradient (˜ 20 MV/m) superconducting RF (SRF) cavity. The electrons are returned back to the cavity with a 180° phase shift to recover the energy back into the cavity before being dumped. A design and development of a half-cell electron gun and a five-cell SRF linac cavity are presented. Several RF and beam dynamics issues ultimately resulting in an optimum cavity design are discussed in detail.

Beam dynamics issues in linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Seeman, J.T.

1989-06-01

The primary goal of present and future linear colliders is to maximize the integrated luminosity for the experimental program. Beam dynamics plays a central role in the maximization of integrated luminosity. It is the major issue in the production of small beam sizes and low experimental backgrounds and is also an important factor in the production of particle numbers, in the acceleration process, and in the number of bunches. The beam dynamics effects on bunches which are extracted from the damping rings, accelerated in the linac, collimated, momentum analyzed, and finally delivered to the final focus are reviewed. The effectsmore » of bunch compression, transverse and longitudinal wakefields, BNS damping, energy definition, dispersion, emittance, bunch aspect ratio, feedback, and stability are all important. 11 refs., 1 tab.« less

Power supply and pulsing strategies for the future linear colliders

NASA Astrophysics Data System (ADS)

Brogna, A. S.; Göttlicher, P.; Weber, M.

2012-02-01

The concept of the power delivery systems of the future linear colliders exploits the pulsed bunch structure of the beam in order to minimize the average current in the cables and the electronics and thus to reduce the material budget and heat dissipation. Although modern integrated circuit technologies are already available to design a low-power system, the concepts on how to pulse the front-end electronics and further reduce the power are not yet well understood. We propose a possible implementation of a power pulsing system based on a DC/DC converter and we choose the Analog Hadron Calorimeter as a specific example. The model features large switching currents of electronic modules in short time intervals to stimulate the inductive components along the cables and interconnections.

Physics Goals for the Planned Next Linear Collider Engineering Test Facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Raubenheimer, Tor O

2001-10-02

The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well asmore » of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.« less

Physics goals for the planned next linear collider engineering test facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Courtlandt L Bohn et al.

2001-06-26

The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well asmore » of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.« less

Physics goals for the planned next linear collider engineering test facility.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bohn, C.; Michelotti, L.; Ostiguy, J.-F.

2001-07-17

The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well asmore » of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.« less

Multipacting optimization of a 750 MHz rf dipole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Delayen, Jean R.; Castillo, Alejandro

2014-12-01

Crab crossing schemes have been proposed to re-instate luminosity degradation due to crossing angles at the interaction points in next generation colliders to avoid the use of sharp bending magnets and their resulting large synchrotron radiation generation, highly undessirable in the detector region. The rf dipole has been considered for a different set of applications in several machines, both rings and linear colliders. We present in this paper a study of the effects on the multipacting levels and location depending on geometrical variations on the design for a crabbing/deflecting application in a high current (3/0.5 A), high repetition (750 MHz)more » electron/proton collider, as a matter to provide a comparison point for similar applications of rf dipoles.« less

Design, construction and commissioning of the Digital Hadron Calorimeter—DHCAL

NASA Astrophysics Data System (ADS)

Adams, C.; Bambaugh, A.; Bilki, B.; Butler, J.; Corriveau, F.; Cundiff, T.; Drake, G.; Francis, K.; Furst, B.; Guarino, V.; Haberichter, B.; Hazen, E.; Hoff, J.; Holm, S.; Kreps, A.; DeLurgio, P.; Matijas, Z.; Dal Monte, L.; Mucia, N.; Norbeck, E.; Northacker, D.; Onel, Y.; Pollack, B.; Repond, J.; Schlereth, J.; Skrzecz, F.; Smith, J. R.; Trojand, D.; Underwood, D.; Velasco, M.; Walendziak, J.; Wood, K.; Wu, S.; Xia, L.; Zhang, Q.; Zhao, A.

2016-07-01

A novel hadron calorimeter is being developed for future lepton colliding beam detectors. The calorimeter is optimized for the application of Particle Flow Algorithms (PFAs) to the measurement of hadronic jets and features a very finely segmented readout with 1 × 1 cm2 cells. The active media of the calorimeter are Resistive Plate Chambers (RPCs) with a digital, i.e. one-bit, readout. To first order the energy of incident particles in this calorimeter is reconstructed as being proportional to the number of pads with a signal over a given threshold. A large-scale prototype calorimeter with approximately 500,000 readout channels has been built and underwent extensive testing in the Fermilab and CERN test beams. This paper reports on the design, construction, and commissioning of this prototype calorimeter.

On Defining Mass

NASA Astrophysics Data System (ADS)

Hecht, Eugene

2011-01-01

Though central to any pedagogical development of physics, the concept of mass is still not well understood. Properly defining mass has proven to be far more daunting than contemporary textbooks would have us believe. And yet today the origin of mass is one of the most aggressively pursued areas of research in all of physics. Much of the excitement surrounding the Large Hadron Collider at CERN is associated with discovering the mechanism responsible for the masses of the elementary particles. This paper will first briefly examine the leading definitions, pointing out their shortcomings. Then, utilizing relativity theory, it will propose—for consideration by the community of physicists—a conceptual definition of mass predicated on the more fundamental concept of energy, more fundamental in that everything that has mass has energy, yet not everything that has energy has mass.

Prediction of the thermal annealing of thick oxide metal-oxide-semiconductor dosimeters irradiated in a harsh radiation environment

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ravotti, F.; Glaser, M.; Saigne, F.

Radiation-sensing metal-oxide-semiconductor field-effect transistors produced by the laboratory LAAS-CNRS were exposed to a harsh hadron field that represents the real radiation environment expected at the CERN Large Hadron Collider experiments. The long-term stability of the transistor's I{sub ds}-V{sub gs} characteristic was investigated using the isochronal annealing technique. In this work, devices exposed to high intensity hadron levels ({phi}{>=}10{sup 12} neutrons/cm{sup 2}) show evidences of displacement damages in the I{sub ds}-V{sub gs} annealing behavior. By comparing experimental and simulated results over 14 months, the isochronal annealing method, originally devoted to oxide trapped charge, is shown to enable prediction of the recoverymore » of silicon bulk defects.« less

Data Bookkeeping Service 3 - Providing Event Metadata in CMS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Giffels, Manuel; Guo, Y.; Riley, Daniel

The Data Bookkeeping Service 3 provides a catalog of event metadata for Monte Carlo and recorded data of the Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider (LHC) at CERN, Geneva. It comprises all necessary information for tracking datasets, their processing history and associations between runs, files and datasets, on a large scale of about 200, 000 datasets and more than 40 million files, which adds up in around 700 GB of metadata. The DBS is an essential part of the CMS Data Management and Workload Management (DMWM) systems [1], all kind of data-processing like Monte Carlo production,more » processing of recorded event data as well as physics analysis done by the users are heavily relying on the information stored in DBS.« less

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bharucha, A.; Bigi, I. I.; Bobeth, C.

During 2011 the LHCb experiment at CERN collected 1.0 fb -1 of √s=7~TeV pp collisions. Due to the large heavy quark production cross-sections, these data provide unprecedented samples of heavy flavoured hadrons. The first results from LHCb have made a significant impact on the flavour physics landscape and have definitively proved the concept of a dedicated experiment in the forward region at a hadron collider. This document discusses the implications of these first measurements on classes of extensions to the Standard Model, bearing in mind the interplay with the results of searches for on-shell production of new particles at ATLASmore » and CMS. The physics potential of an upgrade to the LHCb detector, which would allow an order of magnitude more data to be collected, is emphasised.« less

Controlling front-end electronics boards using commercial solutions

NASA Astrophysics Data System (ADS)

Beneyton, R.; Gaspar, C.; Jost, B.; Schmeling, S.

2002-04-01

LHCb is a dedicated B-physics experiment under construction at CERN's large hadron collider (LHC) accelerator. This paper will describe the novel approach LHCb is taking toward controlling and monitoring of electronics boards. Instead of using the bus in a crate to exercise control over the boards, we use credit-card sized personal computers (CCPCs) connected via Ethernet to cheap control PCs. The CCPCs will provide a simple parallel, I2C, and JTAG buses toward the electronics board. Each board will be equipped with a CCPC and, hence, will be completely independently controlled. The advantages of this scheme versus the traditional bus-based scheme will be described. Also, the integration of the controls of the electronics boards into a commercial supervisory control and data acquisition (SCADA) system will be shown.

Search for the Standard Model Higgs boson decay to μ +μ - with the ATLAS detector

DOE PAGES

Aad, G.

2014-09-08

In this study, a search is reported for Higgs boson decay to μ +μ - using data with an integrated luminosity of 24.8 fb -1 collected with the ATLAS detector in pp collisions at √s = 7 and 8 TeV at the CERN Large Hadron Collider. The observed dimuon invariant mass distribution is consistent with the Standard Model background-only hypothesis in the 120–150 GeV search range. For a Higgs boson with a mass of 125.5 GeV, the observed (expected) upper limit at the 95% confidence level is 7.0 (7.2) times the Standard Model expectation. This corresponds to an upper limitmore » on the branching ratio BR(H→μ +μ -) of 1.5×10 -3.« less

Elastic Scattering and Total Cross-Section in p+p Reactions --As Measured by the LHC Experiment TOTEM at √{s} = 7 TeV--

NASA Astrophysics Data System (ADS)

Csörgő, T.; Antchev, G.; Aspell, P.; Atanassov, I.; Avati, V.; Baechler, J.; Berardi, V.; Berretti, M.; Bossini, E.; Bozzo, M.; Brogi, P.; Brücken, E.; Buzzo, A.; Cafagna, F. S.; Calicchio, M.; Catanesi, M. G.; Covault, C.; Csanád, M.; Deile, M.; Dimovasili, E.; Doubek, M.; Eggert, K.; Eremin, V.; Ferretti, R.; Ferro, F.; Fiergolski, A.; Garcia, F.; Giani, S.; Greco, V.; Grzanka, L.; Heino, J.; Hilden, T.; Intonti, M. R.; Janda, M.; Kašpar, J.; Kopal, J.; Kundrát, V.; Kurvinen, K.; Lami, S.; Latino, G.; Lauhakangas, R.; Leszko, T.; Lippmaa, E.; Lokajíček, M.; Lo Vetere, M.; Lucas Rodríguez, F.; Macrí, M.; Magaletti, L.; Magazzù, G.; Mercadante, A.; Meucci, M.; Minutoli, S.; Nemes, F.; Niewiadomski, H.; Noschis, E.; Novák, T.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Österberg, K.; Palazzi, P.; Perrot, A.-L.; Pedreschi, E.; PetäJäjärvi, J.; Procházka, J.; Quinto, M.; Radermacher, E.; Radicioni, E.; Ravotti, F.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Saarikko, H.; Sanguinetti, G.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Sziklai, J.; Taylor, C.; Turini, N.; Vacek, V.; Vítek, M.; Welti, J.; Whitmore, J.; Totem Collaboration

Proton-proton elastic scattering has been measured by the TOTEMexperiment at the CERN Large Hadron Collider at √{s} = 7 TeV in special runs with the Roman Pot detectors placed as close to the outgoing beam as seven times the transverse beam size. The differential cross-section measurements are reported in the |t|-range of 0.36 to 2.5 GeV^{2}. Extending the range of data to low t values from 0.02 to 0.33 GeV^2, and utilizing the luminosity measurements of CMS, the total proton-proton cross section at √{s} = 7 TeV is measured to be (98.3 ± 0.2^{stat} ± 2.8^{syst}) mb.

The TOTEM Experiment at the CERN Large Hadron Collider

NASA Astrophysics Data System (ADS)

TOTEM Collaboration; Anelli, G.; Antchev, G.; Aspell, P.; Avati, V.; Bagliesi, M. G.; Berardi, V.; Berretti, M.; Boccone, V.; Bottigli, U.; Bozzo, M.; Brücken, E.; Buzzo, A.; Cafagna, F.; Calicchio, M.; Capurro, F.; Catanesi, M. G.; Catastini, P. L.; Cecchi, R.; Cerchi, S.; Cereseto, R.; Ciocci, M. A.; Cuneo, S.; Da Vià, C.; David, E.; Deile, M.; Dimovasili, E.; Doubrava, M.; Eggert, K.; Eremin, V.; Ferro, F.; Foussat, A.; Galuška, M.; Garcia, F.; Gherarducci, F.; Giani, S.; Greco, V.; Hasi, J.; Haug, F.; Heino, J.; Hilden, T.; Jarron, P.; Joram, C.; Kalliopuska, J.; Kaplon, J.; Kašpar, J.; Kundrát, V.; Kurvinen, K.; Lacroix, J. M.; Lami, S.; Latino, G.; Lauhakangas, R.; Lippmaa, E.; Lokajíček, M.; Lo Vetere, M.; Rodriguez, F. Lucas; Macina, D.; Macrí, M.; Magazzù, C.; Magazzù, G.; Magri, A.; Maire, G.; Manco, A.; Meucci, M.; Minutoli, S.; Morelli, A.; Musico, P.; Negri, M.; Niewiadomski, H.; Noschis, E.; Notarnicola, G.; Oliveri, E.; Oljemark, F.; Orava, R.; Oriunno, M.; Perrot, A.-L.; Österberg, K.; Paoletti, R.; Pedreschi, E.; Petäjäjärvi, J.; Pollovio, P.; Quinto, M.; Radermacher, E.; Radicioni, E.; Rangod, S.; Ravotti, F.; Rella, G.; Robutti, E.; Ropelewski, L.; Ruggiero, G.; Rummel, A.; Saarikko, H.; Sanguinetti, G.; Santroni, A.; Scribano, A.; Sette, G.; Snoeys, W.; Spinella, F.; Squillacioti, P.; Ster, A.; Taylor, C.; Tazzioli, A.; Torazza, D.; Trovato, A.; Trummal, A.; Turini, N.; Vacek, V.; Van Remortel, N.; Vinš, V.; Watts, S.; Whitmore, J.; Wu, J.

2008-08-01

The TOTEM Experiment will measure the total pp cross-section with the luminosity-independent method and study elastic and diffractive scattering at the LHC. To achieve optimum forward coverage for charged particles emitted by the pp collisions in the interaction point IP5, two tracking telescopes, T1 and T2, will be installed on each side in the pseudorapidity region 3.1 <= |η| <= 6.5, and Roman Pot stations will be placed at distances of ±147 m and ±220 m from IP5. Being an independent experiment but technically integrated into CMS, TOTEM will first operate in standalone mode to pursue its own physics programme and at a later stage together with CMS for a common physics programme. This article gives a description of the TOTEM apparatus and its performance.

Power Supplies for High Energy Particle Accelerators

NASA Astrophysics Data System (ADS)

Dey, Pranab Kumar

2016-06-01

The on-going research and the development projects with Large Hadron Collider at CERN, Geneva, Switzerland has generated enormous enthusiasm and interest amongst all to know about the ultimate findings on `God's Particle'. This paper has made an attempt to unfold the power supply requirements and the methodology adopted to provide the stringent demand of such high energy particle accelerators during the initial stages of the search for the ultimate particles. An attempt has also been made to highlight the present status on the requirement of power supplies in some high energy accelerators with a view that, precautionary measures can be drawn during design and development from earlier experience which will be of help for the proposed third generation synchrotron to be installed in India at a huge cost.

Top anti-top Asymmetries at the Tevatron and the LHC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Peters, Yvonne Reinhild

2012-11-01

The heaviest known elementary particle today, the top quark, has been discovered in 1995 by the CDF and D0 collaborations at the Tevatron proton antiproton collider at Fermilab. Recently, the CDF and D0 collaborations have studied the forward-backward asymmetry in ttbar events, resulting in measured values larger than the standard model prediction. With the start of the LHC at CERN in 2010, a new top quark factory has opened and asymmetry measurements in ttbar have also been performed in a proton proton environment with higher collision energy. No deviations from the standard model have been noticed so far in themore » measurements of ATLAS and CMS. This article discusses recent results of asymmetry measurements in ttbar events of the ATLAS, CDF, CMS and D0 collaborations.« less

Single event effects on the APV25 front-end chip

NASA Astrophysics Data System (ADS)

Friedl, M.; Bauer, T.; Pernicka, M.

2003-03-01

The Compact Muon Solenoid (CMS) experiment at the Large Hadron Collider at CERN will include a Silicon Strip Tracker covering a sensitive area of 206 m2. About ten million channels will be read out by APV25 front-end chips, fabricated in the 0.25 μm deep submicron process. Although permanent damage is not expected within CMS radiation levels, transient Single Event Upsets are inevitable. Moreover, localized ionization can also produce fake signals in the analog circuitry. Eight APV25 chips were exposed to a high-intensity pion beam at the Paul Scherrer Institute (Villigen/CH) to study the radiation induced effects in detail. The results, which are compatible to similar measurements performed with heavy ions, are used to predict the chip error rate at CMS.

ALICE in the early Universe wonderland

NASA Astrophysics Data System (ADS)

Di Nezza, Pasquale

2012-03-01

In these years the Large Hadron Collider (LHC) at CERN is probing, for the first time, physics at energy scales more than an order of magnitude beyond that of the Standard Model. These experiments explore an energy regime of particle physics where phenomena, such as supersymmetry and Grand Unified Theories, may become relevant. Certainly, the LHC should shed light on the mechanism of electroweak symmetry breaking and may discover the first fundamental scalar particle seen in nature. The collisions of heavy ions (Pb - Pb) will create the same "soup" the early Universe had at the epoch of 10-5 seconds. In general, there is a strong and growing interplay between particle physics and cosmology, in particular in the possible production of mini black holes and dark matter candidates like the lightest neutralino in the MSSM.

Data Aggregation System: A system for information retrieval on demand over relational and non-relational distributed data sources

DOE Office of Scientific and Technical Information (OSTI.GOV)

Ball, G.; Kuznetsov, V.; Evans, D.

We present the Data Aggregation System, a system for information retrieval and aggregation from heterogenous sources of relational and non-relational data for the Compact Muon Solenoid experiment on the CERN Large Hadron Collider. The experiment currently has a number of organically-developed data sources, including front-ends to a number of different relational databases and non-database data services which do not share common data structures or APIs (Application Programming Interfaces), and cannot at this stage be readily converged. DAS provides a single interface for querying all these services, a caching layer to speed up access to expensive underlying calls and the abilitymore » to merge records from different data services pertaining to a single primary key.« less

AGIS: Evolution of Distributed Computing information system for ATLAS

NASA Astrophysics Data System (ADS)

Anisenkov, A.; Di Girolamo, A.; Alandes, M.; Karavakis, E.

2015-12-01

ATLAS, a particle physics experiment at the Large Hadron Collider at CERN, produces petabytes of data annually through simulation production and tens of petabytes of data per year from the detector itself. The ATLAS computing model embraces the Grid paradigm and a high degree of decentralization of computing resources in order to meet the ATLAS requirements of petabytes scale data operations. It has been evolved after the first period of LHC data taking (Run-1) in order to cope with new challenges of the upcoming Run- 2. In this paper we describe the evolution and recent developments of the ATLAS Grid Information System (AGIS), developed in order to integrate configuration and status information about resources, services and topology of the computing infrastructure used by the ATLAS Distributed Computing applications and services.

Measurement of the W + W - production cross section in pp collisions at a centre-of-mass energy of s = 13 TeV with the ATLAS experiment

DOE PAGES

Aaboud, M.; Aad, G.; Abbott, B.; ...

2017-08-30

The production of opposite-charge W-boson pairs in proton–proton collisions atmore » $$\\sqrt{s}$$=13 TeV is measured using data corresponding to 3.16 fb -1 of integrated luminosity collected by the ATLAS detector at the CERN Large Hadron Collider in 2015. Candidate W-boson pairs are selected by identifying their leptonic decays into an electron, a muon and neutrinos. Events with reconstructed jets are not included in the candidate event sample. The cross-section measurement is performed in a fiducial phase space close to the experimental acceptance and is compared to theoretical predictions. In conclusion, agreement is found between the measurement and the most accurate calculations available.« less

Z0-tagged jet event asymmetry in heavy-ion collisions at the CERN large hadron collider.

PubMed

Neufeld, R B; Vitev, I

2012-06-15

Tagged jet measurements provide a promising experimental channel to quantify the similarities and differences in the mechanisms of jet production in proton-proton and nucleus-nucleus collisions. We present the first calculation of the transverse momentum asymmetry of Z0/γ*-tagged jet events in sqrt[s]=2.76  TeV reactions at the LHC. Our results combine the O(G(F)α(s)2) perturbative cross sections with the radiative and collisional processes that modify parton showers in the presence of dense strongly interacting matter. We find that a strong asymmetry is generated in central lead-lead reactions that has little sensitivity to the fluctuations of the underlying soft hadronic background. We present theoretical model predictions for its shape and magnitude.

Alignment of the Stanford Linear Collider Arcs: Concepts and results

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pitthan, R.; Bell, B.; Friedsam, H.

1987-02-01

The alignment of the Arcs for the Stanford Linear Collider at SLAC has posed problems in accelerator survey and alignment not encountered before. These problems come less from the tight tolerances of 0.1 mm, although reaching such a tight statistically defined accuracy in a controlled manner is difficult enough, but from the absence of a common reference plane for the Arcs. Traditional circular accelerators, including HERA and LEP, have been designed in one plane referenced to local gravity. For the SLC Arcs no such single plane exists. Methods and concepts developed to solve these and other problems, connected with themore » unique design of SLC, range from the first use of satellites for accelerator alignment, use of electronic laser theodolites for placement of components, computer control of the manual adjustment process, complete automation of the data flow incorporating the most advanced concepts of geodesy, strict separation of survey and alignment, to linear principal component analysis for the final statistical smoothing of the mechanical components.« less

Do Gluons Carry Proton Spin? - Toward Resolving the Spin Crisis (445th Brookhaven Lecture)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bazilevsky, Alexander

2009-01-21

Just as Earth and other planets spin within the solar system, subatomic quark and gluon particles spin within the protons and neutrons that spin within the nucleus of an atom. Quantum Chromodynamics (QCD) is a theory that describes interactions between subatomic particles and it has played a defining role in understanding the spin of protons and neutrons, which make up most of the visible mass in the universe. Experiments first completed at CERN and furthered at several other laboratories around the world revealed that surprisingly, quarks and their partnering anti-quarks are responsible for only 20 to 30 percent of protonmore » spin. These findings pointed to what would become known as "spin crisis." More recent experiments at BNL's Relativistic Heavy Ion Collider (RHIC), the first collider to smash protons that are "polarized," or made to spin in the same orientation, have helped to isolate the role of the gluon's spin within the spinning proton in hopes of resolving this crisis. In his lecture, Bazilevsky will explain how data from RHIC's PHENIX and STAR detectors help to reveal the role of gluons in the proton's spin. Bazilevsky will also discuss long- and short-term plans to attain a deeper look into the proton spin structure, utilizing RHIC and its future upgrades« less

A programming framework for data streaming on the Xeon Phi

NASA Astrophysics Data System (ADS)

Chapeland, S.; ALICE Collaboration

2017-10-01

ALICE (A Large Ion Collider Experiment) is the dedicated heavy-ion detector studying the physics of strongly interacting matter and the quark-gluon plasma at the CERN LHC (Large Hadron Collider). After the second long shut-down of the LHC, the ALICE detector will be upgraded to cope with an interaction rate of 50 kHz in Pb-Pb collisions, producing in the online computing system (O2) a sustained throughput of 3.4 TB/s. This data will be processed on the fly so that the stream to permanent storage does not exceed 90 GB/s peak, the raw data being discarded. In the context of assessing different computing platforms for the O2 system, we have developed a framework for the Intel Xeon Phi processors (MIC). It provides the components to build a processing pipeline streaming the data from the PC memory to a pool of permanent threads running on the MIC, and back to the host after processing. It is based on explicit offloading mechanisms (data transfer, asynchronous tasks) and basic building blocks (FIFOs, memory pools, C++11 threads). The user only needs to implement the processing method to be run on the MIC. We present in this paper the architecture, implementation, and performance of this system.

Impact of large beam-induced heat loads on the transient operation of the beam screens and the cryogenic plants of the Future Circular Collider (FCC)

NASA Astrophysics Data System (ADS)

Correia Rodrigues, H.; Tavian, L.

2017-12-01

The Future Circular Collider (FCC) under study at CERN will produce 50-TeV high-energy proton beams. The high-energy particle beams are bent by 16-T superconducting dipole magnets operating at 1.9 K and distributed over a circumference of 80 km. The circulating beams induce 5 MW of dynamic heat loads by several processes such as synchrotron radiation, resistive dissipation of beam image currents and electron clouds. These beam-induced heat loads will be intercepted by beam screens operating between 40 and 60 K and induce transients during beam injection. Energy ramp-up and beam dumping on the distributed beam-screen cooling loops, the sector cryogenic plants and the dedicated circulators. Based on the current baseline parameters, numerical simulations of the fluid flow in the cryogenic distribution system during a beam operation cycle were performed. The effects of the thermal inertia of the headers on the helium flow temperature at the cryogenic plant inlet as well as the temperature gradient experienced by the beam screen has been assessed. Additionally, this work enabled a thorough exergetic analysis of different cryogenic plant configurations and laid the building-block for establishing design specification of cold and warm circulators.

Constraining the right-handed gauge boson mass from lepton number violating meson decays in a low scale left-right model

NASA Astrophysics Data System (ADS)

Mandal, Sanjoy; Mitra, Manimala; Sinha, Nita

2017-08-01

We analyze the lepton number violating (LNV) meson decays that arise in a TeV scale left-right symmetry model. The right-handed Majorana neutrino N along with the right-handed or Standard Model gauge bosons mediate the meson decays and provide a resonant enhancement of the rates if the mass of N (MN) lies in the range ˜(100 MeV - 5 GeV ) . Using the expected upper limits on the number of events for the LNV decay modes M1+→ℓ+ℓ+ π- (M1=B,D,Ds, K ), we derive constraints plausible on the mass of the right handed charged gauge boson by future searches at the ongoing NA62 and LHCb experiments at CERN, the upcoming Belle II at SuperKEK, as well as at the proposed future experiments, SHiP and FCC-ee. These bounds are complimentary to the limits from the same-sign dilepton search at the Large Hadron Collider (LHC). The very high intensity of charmed mesons expected to be produced at SHiP will result in a far more stringent bound, MW R>18.4 TeV (corresponding to MN=1.46 GeV ), than the other existing bounds from collider and neutrinoless double beta decay searches.

The XXth International Workshop High Energy Physics and Quantum Field Theory

NASA Astrophysics Data System (ADS)

The Workshop continues a series of workshops started by the Skobeltsyn Institute of Nuclear Physics of Lomonosov Moscow State University (SINP MSU) in 1985 and conceived with the purpose of presenting topics of current interest and providing a stimulating environment for scientific discussion on new developments in theoretical and experimental high energy physics and physical programs for future colliders. Traditionally the list of workshop attendees includes a great number of active young scientists and students from Russia and other countries. This year Workshop is organized jointly by the SINP MSU and the Southern Federal University (SFedU) and will take place in the holiday hotel "Luchezarniy" (Effulgent) situated on the Black Sea shore in a picturesque natural park in the suburb of the largest Russian resort city Sochi - the host city of the XXII Olympic Winter Games to be held in 2014. The main topics to be covered are: Experimental results from the LHC. Tevatron summary: the status of the Standard Model and the boundaries on BSM physics. Future physics at Linear Colliders and super B-factories. Extensions of the Standard Model and their phenomenological consequences at the LHC and Linear Colliders: SUSY extensions of the Standard Model; particle interactions in space-time with extra dimensions; strings, quantum groups and new ideas from modern algebra and geometry. Higher order corrections and resummations for collider phenomenology. Automatic calculations of Feynman diagrams and Monte Carlo simulations. LHC/LC and astroparticle/cosmology connections. Modern nuclear physics and relativistic nucleous-nucleous collisions.

First experience with carbon stripping foils for the 160 MeV H- injection into the CERN PSB

NASA Astrophysics Data System (ADS)

Weterings, Wim; Bracco, Chiara; Jorat, Louise; Noulibos, Remy; van Trappen, Pieter

2018-05-01

160 MeV H- beam will be delivered from the new CERN linear accelerator (Linac4) to the Proton Synchrotron Booster (PSB), using a H- charge-exchange injection system. A 200 µg/cm2 carbon stripping foil will convert H- into protons by stripping off the electrons. The H- charge-exchange injection principle will be used for the first time in the CERN accelerator complex and involves many challenges. In order to gain experience with the foil changing mechanism and the very fragile foils, in 2016, prior to the installation in the PSB, a stripping foil test stand has been installed in the Linac4 transfer line. In addition, parts of the future PSB injection equipment are also temporarily installed in the Linac4 transfer line for tests with a 160 MeV H- commissioning proton beam. This paper describes the foil changing mechanism and control system, summarizes the practical experience of gluing and handling these foils and reports on the first results with beam.

Higgs physics at the CLIC electron-positron linear collider.

PubMed

Abramowicz, H; Abusleme, A; Afanaciev, K; Alipour Tehrani, N; Balázs, C; Benhammou, Y; Benoit, M; Bilki, B; Blaising, J-J; Boland, M J; Boronat, M; Borysov, O; Božović-Jelisavčić, I; Buckland, M; Bugiel, S; Burrows, P N; Charles, T K; Daniluk, W; Dannheim, D; Dasgupta, R; Demarteau, M; Díaz Gutierrez, M A; Eigen, G; Elsener, K; Felzmann, U; Firlej, M; Firu, E; Fiutowski, T; Fuster, J; Gabriel, M; Gaede, F; García, I; Ghenescu, V; Goldstein, J; Green, S; Grefe, C; Hauschild, M; Hawkes, C; Hynds, D; Idzik, M; Kačarević, G; Kalinowski, J; Kananov, S; Klempt, W; Kopec, M; Krawczyk, M; Krupa, B; Kucharczyk, M; Kulis, S; Laštovička, T; Lesiak, T; Levy, A; Levy, I; Linssen, L; Lukić, S; Maier, A A; Makarenko, V; Marshall, J S; Martin, V J; Mei, K; Milutinović-Dumbelović, G; Moroń, J; Moszczyński, A; Moya, D; Münker, R M; Münnich, A; Neagu, A T; Nikiforou, N; Nikolopoulos, K; Nürnberg, A; Pandurović, M; Pawlik, B; Perez Codina, E; Peric, I; Petric, M; Pitters, F; Poss, S G; Preda, T; Protopopescu, D; Rassool, R; Redford, S; Repond, J; Robson, A; Roloff, P; Ros, E; Rosenblat, O; Ruiz-Jimeno, A; Sailer, A; Schlatter, D; Schulte, D; Shumeiko, N; Sicking, E; Simon, F; Simoniello, R; Sopicki, P; Stapnes, S; Ström, R; Strube, J; Świentek, K P; Szalay, M; Tesař, M; Thomson, M A; Trenado, J; Uggerhøj, U I; van der Kolk, N; van der Kraaij, E; Vicente Barreto Pinto, M; Vila, I; Vogel Gonzalez, M; Vos, M; Vossebeld, J; Watson, M; Watson, N; Weber, M A; Weerts, H; Wells, J D; Weuste, L; Winter, A; Wojtoń, T; Xia, L; Xu, B; Żarnecki, A F; Zawiejski, L; Zgura, I-S

2017-01-01

The Compact Linear Collider (CLIC) is an option for a future [Formula: see text] collider operating at centre-of-mass energies up to [Formula: see text], providing sensitivity to a wide range of new physics phenomena and precision physics measurements at the energy frontier. This paper is the first comprehensive presentation of the Higgs physics reach of CLIC operating at three energy stages: [Formula: see text], 1.4 and [Formula: see text]. The initial stage of operation allows the study of Higgs boson production in Higgsstrahlung ([Formula: see text]) and [Formula: see text]-fusion ([Formula: see text]), resulting in precise measurements of the production cross sections, the Higgs total decay width [Formula: see text], and model-independent determinations of the Higgs couplings. Operation at [Formula: see text] provides high-statistics samples of Higgs bosons produced through [Formula: see text]-fusion, enabling tight constraints on the Higgs boson couplings. Studies of the rarer processes [Formula: see text] and [Formula: see text] allow measurements of the top Yukawa coupling and the Higgs boson self-coupling. This paper presents detailed studies of the precision achievable with Higgs measurements at CLIC and describes the interpretation of these measurements in a global fit.

A First Assessment of Two-Beam Linear Colliders and Longer-Term Two-Beam R& D Issues at SLAC

DOE Office of Scientific and Technical Information (OSTI.GOV)

Loew, Greg

2001-06-05

The purpose of this document is to summarize the work that has been done at SLAC in the last three or four months to assess the possibilities of two-beam linear colliders proposed by Ron Ruth, and to compare these colliders to the current NLC designs and their costs. The work is based on general discussions with C. Adolphsen, D. Burke, J. Irwin, J. Paterson, R. Ruth, T. Lavine and T. Raubenheimer, with considerable work done by the latter two. Given the complexities of these machines, the fact that the designs are far from complete and that all cost estimates aremore » still in a state of flux, it is clear that the conclusions drawn in this report cannot be cast in concrete. On the other hand, it does not seem too early to present the results that have been gathered so far, even if the facts contain significant uncertainties and the costs have large error bars. Now that R. Ruth has returned to SLAC, he will be able to add his point of view to the discussion. At this time, the conclusions presented here are the sole responsibility of the author.« less

MADANALYSIS 5, a user-friendly framework for collider phenomenology

NASA Astrophysics Data System (ADS)

Conte, Eric; Fuks, Benjamin; Serret, Guillaume

2013-01-01

We present MADANALYSIS 5, a new framework for phenomenological investigations at particle colliders. Based on a C++ kernel, this program allows us to efficiently perform, in a straightforward and user-friendly fashion, sophisticated physics analyses of event files such as those generated by a large class of Monte Carlo event generators. MADANALYSIS 5 comes with two modes of running. The first one, easier to handle, uses the strengths of a powerful PYTHON interface in order to implement physics analyses by means of a set of intuitive commands. The second one requires one to implement the analyses in the C++ programming language, directly within the core of the analysis framework. This opens unlimited possibilities concerning the level of complexity which can be reached, being only limited by the programming skills and the originality of the user. Program summaryProgram title: MadAnalysis 5 Catalogue identifier: AENO_v1_0 Program summary URL:http://cpc.cs.qub.ac.uk/summaries/AENO_v1_0.html Program obtainable from: CPC Program Library, Queen's University, Belfast, N. Ireland Licensing provisions: Permission to use, copy, modify and distribute this program is granted under the terms of the GNU General Public License. No. of lines in distributed program, including test data, etc.: 31087 No. of bytes in distributed program, including test data, etc.: 399105 Distribution format: tar.gz Programming language: PYTHON, C++. Computer: All platforms on which Python version 2.7, Root version 5.27 and the g++ compiler are available. Compatibility with newer versions of these programs is also ensured. However, the Python version must be below version 3.0. Operating system: Unix, Linux and Mac OS operating systems on which the above-mentioned versions of Python and Root, as well as g++, are available. Classification: 11.1. External routines: ROOT (http://root.cern.ch/drupal/) Nature of problem: Implementing sophisticated phenomenological analyses in high-energy physics through a flexible, efficient and straightforward fashion, starting from event files such as those produced by Monte Carlo event generators. The event files can have been matched or not to parton-showering and can have been processed or not by a (fast) simulation of a detector. According to the sophistication level of the event files (parton-level, hadron-level, reconstructed-level), one must note that several input formats are possible. Solution method: We implement an interface allowing the production of predefined as well as user-defined histograms for a large class of kinematical distributions after applying a set of event selection cuts specified by the user. This therefore allows us to devise robust and novel search strategies for collider experiments, such as those currently running at the Large Hadron Collider at CERN, in a very efficient way. Restrictions: Unsupported event file format. Unusual features: The code is fully based on object representations for events, particles, reconstructed objects and cuts, which facilitates the implementation of an analysis. Running time: It depends on the purposes of the user and on the number of events to process. It varies from a few seconds to the order of the minute for several millions of events.

Analysis of 440 GeV proton beam–matter interaction experiments at the High Radiation Materials test facility at CERN

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burkart, F.; Schmidt, R.; Wollmann, D.

2015-08-07

In a previous paper [Schmidt et al., Phys. Plasmas 21, 080701 (2014)], we presented the first results on beam–matter interaction experiments that were carried out at the High Radiation Materials test facility at CERN. In these experiments, extended cylindrical targets of solid copper were irradiated with beam of 440 GeV protons delivered by the Super Proton Synchrotron (SPS). The beam comprised of a large number of high intensity proton bunches, each bunch having a length of 0.5 ns with a 50 ns gap between two neighboring bunches, while the length of this entire bunch train was about 7 μs. These experiments established the existencemore » of the hydrodynamic tunneling phenomenon the first time. Detailed numerical simulations of these experiments were also carried out which were reported in detail in another paper [Tahir et al., Phys. Rev. E 90, 063112 (2014)]. Excellent agreement was found between the experimental measurements and the simulation results that validate our previous simulations done using the Large Hadron Collider (LHC) beam of 7 TeV protons [Tahir et al., Phys. Rev. Spec. Top.--Accel. Beams 15, 051003 (2012)]. According to these simulations, the range of the full LHC proton beam and the hadronic shower can be increased by more than an order of magnitude due to the hydrodynamic tunneling, compared to that of a single proton. This effect is of considerable importance for the design of machine protection system for hadron accelerators such as SPS, LHC, and Future Circular Collider. Recently, using metal cutting technology, the targets used in these experiments have been dissected into finer pieces for visual and microscopic inspection in order to establish the precise penetration depth of the protons and the corresponding hadronic shower. This, we believe will be helpful in studying the very important phenomenon of hydrodynamic tunneling in a more quantitative manner. The details of this experimental work together with a comparison with the numerical simulations are presented in this paper.« less

Fermilab | Publications and Videos

Science.gov Websites

International Linear Collider Global Design Effort. Science Node The Science Node is a free online publication , viewers can catch a true behind-the-scenes look of the United States' premier particle physics laboratory

DOE Office of Scientific and Technical Information (OSTI.GOV)

Syphers, M. J.; Chattopadhyay, S.

An overview is provided of the currently envisaged landscape of charged particle accelerators at the energy and intensity frontiers to explore particle physics beyond the standard model via 1-100 TeV-scale lepton and hadron colliders and multi-Megawatt proton accelerators for short- and long- baseline neutrino experiments. The particle beam physics, associated technological challenges and progress to date for these accelerator facilities (LHC, HL-LHC, future 100 TeV p-p colliders, Tev-scale linear and circular electron-positron colliders, high intensity proton accelerator complex PIP-II for DUNE and future upgrade to PIP-III) are outlined. Potential and prospects for advanced “nonlinear dynamic techniques” at the multi-MW levelmore » intensity frontier and advanced “plasma- wakefield-based techniques” at the TeV-scale energy frontier and are also described.« less

Parallel computation of transverse wakes in linear colliders

DOE Office of Scientific and Technical Information (OSTI.GOV)

Zhan, Xiaowei; Ko, Kwok

1996-11-01

SLAC has proposed the detuned structure (DS) as one possible design to control the emittance growth of long bunch trains due to transverse wakefields in the Next Linear Collider (NLC). The DS consists of 206 cells with tapering from cell to cell of the order of few microns to provide Gaussian detuning of the dipole modes. The decoherence of these modes leads to two orders of magnitude reduction in wakefield experienced by the trailing bunch. To model such a large heterogeneous structure realistically is impractical with finite-difference codes using structured grids. The authors have calculated the wakefield in the DSmore » on a parallel computer with a finite-element code using an unstructured grid. The parallel implementation issues are presented along with simulation results that include contributions from higher dipole bands and wall dissipation.« less

Coupling Correction and Beam Dynamics at Ultralow Vertical Emittance in the ALS

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steier, Christoph; Robin, D.; Wolski, A.

2008-03-17

For synchrotron light sources and for damping rings of linear colliders it is important to be able to minimize the vertical emittance and to correct the spurious vertical dispersion. This allows one to maximize the brightness and/or the luminosity. A commonly used tool to measure the skew error distribution is the analysis of orbit response matrices using codes like LOCO. Using the new Matlab version of LOCO and 18 newly installed power supplies for individual skew quadrupoles at the ALS the emittance ratio could be reduced below 0.1% at 1.9 GeV yielding a vertical emittance of about 5 pm. Atmore » those very low emittances, additional effects like intra beam scattering become more important, potentially limiting the minimum emittance for machine like the damping rings of linear colliders.« less

CCD-based vertex detector for ILC

NASA Astrophysics Data System (ADS)

Stefanov, Konstantin D.

2006-12-01

Charge Coupled Devices (CCDs) have been successfully used in several high-energy physics experiments over the last 20 years. Their small pixel size and excellent precision provide a superb tool for studying of short-lived particles and understanding the nature at fundamental level. Over the last few years the Linear Collider Flavour Identification (LCFI) collaboration has developed Column-Parallel CCDs (CPCCD) and CMOS readout chips, to be used for the vertex detector at the International Linear Collider (ILC). The CPCCDs are very fast devices capable of satisfying the challenging requirements imposed by the beam structure of the superconducting accelerator. The first set of prototype devices have been successfully designed, manufactured and tested, with second generation chips on the way. Another idea for CCD-based device, the In-situ Storage Image Sensor (ISIS) is also under development and the first prototype has been manufactured.

Detectors for Linear Colliders: Detector design for a Future Electron-Positron Collider (4/4)

ScienceCinema

Thomson, Mark

2018-05-21

In this lecture I will discuss the issues related to the overall design and optimization of a detector for ILC and CLIC energies. I will concentrate on the two main detector concepts which are being developed in the context of the ILC. Here there has been much recent progress in developing realistic detector models and in understanding the physics performance of the overall detector concept. In addition, I will discuss the how the differences in the detector requirements for the ILC and CLIC impact the overall detector design.

Simulation of the cabling process for Rutherford cables: An advanced finite element model

NASA Astrophysics Data System (ADS)

Cabanes, J.; Garlasche, M.; Bordini, B.; Dallocchio, A.

2016-12-01

In all existing large particle accelerators (Tevatron, HERA, RHIC, LHC) the main superconducting magnets are based on Rutherford cables, which are characterized by having: strands fully transposed with respect to the magnetic field, a significant compaction that assures a large engineering critical current density and a geometry that allows efficient winding of the coils. The Nb3Sn magnets developed in the framework of the HL-LHC project for improving the luminosity of the Large Hadron Collider (LHC) are also based on Rutherford cables. Due to the characteristics of Nb3Sn wires, the cabling process has become a crucial step in the magnet manufacturing. During cabling the wires experience large plastic deformations that strongly modify the geometrical dimensions of the sub-elements constituting the superconducting strand. These deformations are particularly severe on the cable edges and can result in a significant reduction of the cable critical current as well as of the Residual Resistivity Ratio (RRR) of the stabilizing copper. In order to understand the main parameters that rule the cabling process and their impact on the cable performance, CERN has developed a 3D Finite Element (FE) model based on the LS-Dyna® software that simulates the whole cabling process. In the paper the model is presented together with a comparison between experimental and numerical results for a copper cable produced at CERN.

Federated data storage and management infrastructure

NASA Astrophysics Data System (ADS)

Zarochentsev, A.; Kiryanov, A.; Klimentov, A.; Krasnopevtsev, D.; Hristov, P.

2016-10-01

The Large Hadron Collider (LHC)’ operating at the international CERN Laboratory in Geneva, Switzerland, is leading Big Data driven scientific explorations. Experiments at the LHC explore the fundamental nature of matter and the basic forces that shape our universe. Computing models for the High Luminosity LHC era anticipate a growth of storage needs of at least orders of magnitude; it will require new approaches in data storage organization and data handling. In our project we address the fundamental problem of designing of architecture to integrate a distributed heterogeneous disk resources for LHC experiments and other data- intensive science applications and to provide access to data from heterogeneous computing facilities. We have prototyped a federated storage for Russian T1 and T2 centers located in Moscow, St.-Petersburg and Gatchina, as well as Russian / CERN federation. We have conducted extensive tests of underlying network infrastructure and storage endpoints with synthetic performance measurement tools as well as with HENP-specific workloads, including the ones running on supercomputing platform, cloud computing and Grid for ALICE and ATLAS experiments. We will present our current accomplishments with running LHC data analysis remotely and locally to demonstrate our ability to efficiently use federated data storage experiment wide within National Academic facilities for High Energy and Nuclear Physics as well as for other data-intensive science applications, such as bio-informatics.

Physics in ;Real Life;: Accelerator-based Research with Undergraduates

NASA Astrophysics Data System (ADS)

Klay, J. L.

All undergraduates in physics and astronomy should have access to significant research experiences. When given the opportunity to tackle challenging open-ended problems outside the classroom, students build their problem-solving skills in ways that better prepare them for the workplace or future research in graduate school. Accelerator-based research on fundamental nuclear and particle physics can provide a myriad of opportunities for undergraduate involvement in hardware and software development as well as ;big data; analysis. The collaborative nature of large experiments exposes students to scientists of every culture and helps them begin to build their professional network even before they graduate. This paper presents an overview of my experiences - the good, the bad, and the ugly - engaging undergraduates in particle and nuclear physics research at the CERN Large Hadron Collider and the Los Alamos Neutron Science Center.