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Sample records for fnal collider experiment

  1. FNAL Booster intensity, extraction, and synchronization control for collider operation

    SciTech Connect

    Ducar, R.J.; Lackey, J.R.; Tawzer, S.R.

    1987-03-01

    Booster operation for collider physics is considerably different than for fixed target operation. Various scenarios for collider physics, machine studies, and P-Bar targeting may require that the intensity vary from 5E10 PPP to 3E12 PPP at a 15 Hertz machine cycle rate. In addition to the normal Booster single turn extraction mode, collider operations require that the Booster inject into the Main Ring a small number of beam bunches for coalescing into a single high intensity bunch. These bunches must be synchronized such that the center bunch arrives in the RF bucket which corresponds to the zero phase of the coalescing cavity. The system implemented has the ability to deliver a precise fraction of the available 84 Booster beam bunches to Main Ring or to the P-Bar Debuncher via the newly installed AP-4 beam line for tune-up and studies. It is required that all of the various intensity and extraction scenarios be accommodated with minimal operator intervention.

  2. Status of FNAL SciBooNE experiment

    SciTech Connect

    Nakajima, Yasuhiro; /Kyoto U.

    2007-12-01

    SciBooNE is a new experiment at FNAL which will make precision neutrino-nucleus cross section measurements in the one GeV region. These measurements are essential for the future neutrino oscillation experiments. We started data taking in the antineutrino mode on June 8, 2007, and collected 5.19 x 10{sup 19} protons on target (POT) before the accelerator shutdown in August. The first data from SciBooNE are reported in this article.

  3. The FNAL e938 Experiment: The Mexican Contribution to the MINER{nu}A Collaboration

    SciTech Connect

    Felix, J.; Castorena, J.; Higuera, A.; Gutierrez, M. R.; Moreno, G.; Reyes, M. A.; Urrutia, Z.; Zavala, G.; Morfin, J. G.

    2009-04-20

    The MINER{nu}A (Main INjector ExpeRiment for {nu}A) collaboration (http://minerva.fnal.gov//) is a neutrino scattering experiment which uses the NuMI beam-line at Fermilab. It seeks to measure low energy neutrino interactions both to support neutrino oscillation experiments and to study the strong dynamics of the nucleon and nucleus that affect these interactions. It is currently in its final prototyping stage and is preparing for full-scale construction. The first detector module was completed in early 2006 and it is planned to begin taking data in 2009. We present an overview of this experiment, emphasizing the Mexican contribution, and giving the potential physics results that this collaboration can contribute to the physics of neutrino.

  4. Data Plots from FNAL-E907: Main Injector Particle Production Experiment (MIPP)

    DOE Data Explorer

    The Main Injector Particle Production Experiment (FNAL E-907, MIPP), situated in the Meson Center beamline at Fermilab, took data during the first half of 2005. MIPP was designed primarily as an experiment to measure and study in detail the dynamics associated with non-perturbative strong interactions. The primary physics motivation behind MIPP was to restart the study of non-perturbative QCD interactions, which constitute over 99% of the strong interaction cross section. The available data of that time were of poor quality and old and were not in easily accessible form. The Time Projection Chamber (TPC) [6] that was at the heart of the MIPP experiment represented the electronic equivalent of the bubble chamber with vastly superior data acquisition rates. It also digitized the charged tracks in three dimensions, obviating the need for track matching across stereo views. Coupled with the particle identification capability of MIPP, the data from MIPP was intended to add significantly to the knowledge base of non-perturbative QCD. One of the primary goals of MIPP was to verify a general scaling law of inclusive particle production that states that the ratio of a semi-inclusive cross section to an inclusive cross section involving the same particles is a function only of the missing mass squared (M2) of the system and not of the other two Mandelstam variables s and t, the center of mass energy squared and the momentum transfer squared, respectively. [Copied and edited from the following publication: The Main Injector Particle Production Experiment (MIPP) at Fermilab, Rajendran Raja, Institute of Physics (IOP) Publishing, Journal of Physics: Conference Series 9 (2005) 303 û 308, doi:10.1088/1742-6596/9/1/058 at www.iop.org/EJ/article/1742-6596/9/1/058/jpconf5_9_058.pdf] There are approximately 40 data plots available to the public from E907. A proposal to upgrade the MIPP experiment (E-P-960) has been deferred. See the MIPP homepage at http://ppd.fnal.gov/experiments

  5. A Photon Collider Experiment based on SLC

    SciTech Connect

    Gronberg, J

    2003-11-01

    Technology for a photon collider experiment at a future TeV-scale linear collider has been under development for many years. The laser and optics technology has reached the point where a GeV-scale photon collider experiment is now feasible. We report on the photon-photon luminosities that would be achievable at a photon collider experiment based on a refurbished Stanford Linear Collider.

  6. COLLIDE: Collisions into Dust Experiment

    NASA Technical Reports Server (NTRS)

    Colwell, Joshua E.

    1999-01-01

    The Collisions Into Dust Experiment (COLLIDE) was completed and flew on STS-90 in April and May of 1998. After the experiment was returned to Earth, the data and experiment were analyzed. Some anomalies occurred during the flight which prevented a complete set of data from being obtained. However, the experiment did meet its criteria for scientific success and returned surprising results on the outcomes of very low energy collisions into powder. The attached publication, "Low Velocity Microgravity Impact Experiments into Simulated Regolith," describes in detail the scientific background, engineering, and scientific results of COLLIDE. Our scientific conclusions, along with a summary of the anomalies which occurred during flight, are contained in that publication. We offer it as our final report on this grant.

  7. Precision electroweak physics at future collider experiments

    SciTech Connect

    Baur, U.; Demarteau, M.

    1996-11-01

    We present an overview of the present status and prospects for progress in electroweak measurements at future collider experiments leading to precision tests of the Standard Model of Electroweak Interactions. Special attention is paid to the measurement of the {ital W} mass, the effective weak mixing angle, and the determination of the top quark mass. Their constraints on the Higgs boson mass are discussed.

  8. COLLIDE-2: Collisions Into Dust Experiment-2

    NASA Technical Reports Server (NTRS)

    Colwell, Joshua E.

    2002-01-01

    The Collisions Into Dust Experimental (COLLIDE-2) was the second flight of the COLLIDE payload. The payload performs six low-velocity impact experiments to study the collisions that are prevalent in planetary ring systems and in the early stages of planet formation. Each impact experiment is into a target of granular material, and the impacts occur at speeds between 1 and 100 cm/s in microgravity and in a vacuum. The experiments are recorded on digital videotape which is later analyzed. During the period of performance a plan was developed to address some of the technical issues that prevented the first flight of COLLIDE from being a complete success, and also to maximize the scientific return based on the science results from the first flight. The experiment was modified following a series of reviews of the design plan, and underwent extensive testing. The data from the experiment show that the primary goal of identifying transition regimes for low-velocity impacts based on cratering versus accretion was achieved. Following a brief period of storage, the experiment flew regimes for low-velocity impacts based on cratering versus accretion was achieved. as a Hitchhiker payload on the MACH-1 Hitchhiker bridge on STS-108 in December 2001. These data have been analyzed and submitted for publication. That manuscript is attached to this report. The experiment was retrieved in January 2002, and all six impact experiments functioned nominally. Preliminary results were reported at the Lunar and Planetary Science Conference.

  9. Aerogel Cherenkov detectors in colliding beam experiments

    NASA Astrophysics Data System (ADS)

    Danilyuk, A. F.; Kononov, S. A.; Kravchenko, E. A.; Onuchin, A. P.

    2015-05-01

    This review discusses the application of aerogel Cherenkov detectors in colliding beam experiments. Such detectors are used for charged particle identification at velocities at which other methods are ineffective. The paper examines aerogel production technology and how the aerogel optical parameters are measured. Data on threshold Cherenkov counters with direct light collection and on those using wavelength shifters are evaluated. Also presented are data on Ring Image Cherenkov detectors with single and multilayer focusing aerogel radiators.

  10. FNAL system patching design

    SciTech Connect

    Schmidt, Jack; Lilianstrom, Al; Romero, Andy; Dawson, Troy; Sieh, Connie; /Fermilab

    2004-01-01

    FNAL has over 5000 PCs running either Linux or Windows software. Protecting these systems efficiently against the latest vulnerabilities that arise has prompted FNAL to take a more central approach to patching systems. Due to different levels of existing support infrastructures, the patching solution for linux systems differs from that of windows systems. In either case, systems are checked for vulnerabilities by Computer Security using the Nessus tool.

  11. GLADE Global Liquid Argon Detector Experiment: a letter of intent to FNAL

    SciTech Connect

    Thomas, Jennifer

    2012-05-13

    The recent measurements of the {theta}{sub 13} mixing angle, which controls the observable size of any CP violation effects, open a window of opportunity to take advantage of the world's most powerful existing neutrino beam together with recent successes in development of the ultimate detector technology for the detection of electron neutrinos : a liquid argon (LAr) time projection chamber. During this proposed project a 5kt LAr detector (GLADE) will be developed by European groups to be put in a cryostat in the NuMI neutrino beam at Fermi National Accelerator Laboratory in the US and will start taking data in 3-5 years time to address the neutrino mass ordering. The successful fruition of this project, along with nominal exposure at NO{nu}A and T2K, together with information from double beta decay experiments could ascertain that neutrinos are Dirac particles in the next decade.

  12. Recent experience in the fabrication and brazing of ceramic beam tubes for kicker magnets at FNAL

    SciTech Connect

    Ader, C.R.; Jensen, C.; Reilly, R.; Snee, D.; Wilson, J.H.; /Fermilab

    2008-06-01

    Ceramic beam tubes are utilized in numerous kicker magnets in different accelerator rings at Fermi National Accelerator Laboratory. Kovar flanges are brazed onto each beam tube end, since kovar and high alumina ceramic have similar expansion curves. The tube, kovar flange, end piece, and braze foil (titanium/incusil) alloy brazing material are stacked in the furnace and then brazed in the furnace at 1000 C. The ceramic specified is 99.8% Alumina, Al{sub 2}O{sub 3}, a strong recrystallized high-alumina fabricated by slip casting. Recent experience at Fermilab with the fabrication and brazing of these tubes has brought to light numerous problems including tube breakage and cracking and also the difficulty of brazing the tube to produce a leak-tight joint. These problems may be due to the ceramic quality, voids in the ceramic, thinness of the wall, and micro-cracks in the ends which make it difficult to braze because it cannot fill tiny surface cracks which are caused by grain pullout during the cutting process. Solutions which are being investigated include lapping the ends of the tubes before brazing to eliminate the micro-cracks and also metallization of the tubes.

  13. Cooling of electronics in collider experiments

    SciTech Connect

    Richard P. Stanek et al.

    2003-11-07

    Proper cooling of detector electronics is critical to the successful operation of high-energy physics experiments. Collider experiments offer unique challenges based on their physical layouts and hermetic design. Cooling systems can be categorized by the type of detector with which they are associated, their primary mode of heat transfer, the choice of active cooling fluid, their heat removal capacity and the minimum temperature required. One of the more critical detector subsystems to require cooling is the silicon vertex detector, either pixel or strip sensors. A general design philosophy is presented along with a review of the important steps to include in the design process. Factors affecting the detector and cooling system design are categorized. A brief review of some existing and proposed cooling systems for silicon detectors is presented to help set the scale for the range of system designs. Fermilab operates two collider experiments, CDF & D0, both of which have silicon systems embedded in their detectors. A review of the existing silicon cooling system designs and operating experience is presented along with a list of lessons learned.

  14. High luminosity muon scattering at FNAL

    SciTech Connect

    Bazizi, K. ); Conrad, J.; Fang, G. ); Erdmann, M. ); Geesaman, D.; Jackson, H. ); Guyot, C.; Virchaux, M. ); Holmgren, H. ); Malensek, A.; Melanson, H.; Morfin

    1990-02-01

    The charge of this group was to evaluate the physics that can be done with a high luminosity {mu} scattering experiment at FNAL using the upgraded Tevatron muon beam, and consider the apparatus required. In this report, the physics that can be accomplished with a high luminosity {mu} scattering experiment is evaluated. The CERN and FNAL {mu} beams are compared in the context of such an experiment. The expected muon flux with the upgraded machine is estimated. Two possible detectors are compared: the air-core toroid experiment proposed by Guyot et al., and an upgraded version of the E665 double-diode apparatus now in place at FNAL. The relative costs of the detectors are considered. A list of detailed questions that need to be answered regarding the double-diode experiment has be compiled. 2 refs., 10 figs., 2 tabs.

  15. First Results from the Phobos Experiment at the RHIC Collider

    NASA Astrophysics Data System (ADS)

    Katzy, Judith; Back, B. B.; Baker, M. D.; Barton, D. S.; Betts, R. R.; Bindel, R.; Budzanowski, A.; Busza, W.; Carroll, A.; Decowski, M. P.; Garcia, E.; George, N.; Gulbrandsen, K.; Gushue, S.; Halliwell, C.; Heintzelman, G. A.; Henderson, C.; Holyński, R.; Hofman, D.; Holzman, B.; Johnson, E.; Kane, J.; Katzy, J.; Kulinich, P.; Kucewicz, W.; Lin, W. T.; McLeod, D.; Manly, S.; Michalowski, J.; Mignerey, A.; Muelmenstaedt, J.; Nouicer, R.; Olszewski, A.; Pak, R.; Park, I. C.; Pernegger, H.; Reed, C.; Remsberg, L. P.; Reuter, M.; Roland, C.; Roland, G.; Rosenberg, L.; Sarin, P.; Sawicki, P.; Skulski, W.; Steadman, S. G.; Stephans, G. S. F.; Steinberg, P.; Stodulski, M.; Sukhanov, A.; Tang, J.-L.; Teng, R.; Trzupek, A.; Vale, C.; van Nieuwenhuizen, G. J.; Verdier, R.; Wadsworth, B.; Wolfs, F. L. H.; Wosiek, B.; Woźniak, K.; Wuosmaa, A. H.; Wysłouch, B.

    PHOBOS is one of the four experiments at the Relativistic Heavy Ion Collider that started colliding gold nuclei at a center of mass energy of √sNN = 56 and 130 GeV per pair of colliding nucleons in June 2000. The pseudorapidity density of primary charged particles in central collisions has been measured near mid-rapidity.

  16. Low energy [bar p] physics at FNAL

    SciTech Connect

    Hsueh, S.Y.

    1992-12-01

    The charmonium formation experiment is the only low energy [bar p] experiment at FNAL. This paper describes the performance of the Fermilab [bar p] Accumulator during fixed target run for the experiment and the planned upgrades. We also discuss the proposal for the direct CP violation search in [bar p] + p [yields] [bar [Lambda

  17. FNAL central email systems

    SciTech Connect

    Schmidt, Jack; Lilianstrom, Al; Pasetes, Ray; Hill, Kevin; /Fermilab

    2004-10-01

    The FNAL Email System is the primary point of entry for email destined for an employee or user at Fermilab. This centrally supported system is designed for reliability and availability. It uses multiple layers of protection to help ensure that: (1) SPAM messages are tagged properly; (2) All mail is inspected for viruses; and (3) Valid mail gets delivered. This system employs numerous redundant subsystems to accomplish these tasks.

  18. Laser ion source for isobaric heavy ion collider experiment

    NASA Astrophysics Data System (ADS)

    Kanesue, T.; Kumaki, M.; Ikeda, S.; Okamura, M.

    2016-02-01

    Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is 96Ru + 96Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions.

  19. Laser ion source for isobaric heavy ion collider experiment.

    PubMed

    Kanesue, T; Kumaki, M; Ikeda, S; Okamura, M

    2016-02-01

    Heavy-ion collider experiment in isobaric system is under investigation at Relativistic Heavy Ion Collider. For this experiment, ion source is required to maximize the abundance of the intended isotope. The candidate of the experiment is (96)Ru + (96)Zr. Since the natural abundance of particular isotope is low and composition of isotope from ion source depends on the composites of the target, an isotope enriched material may be needed as a target. We studied the performance of the laser ion source required for the experiment for Zr ions. PMID:26931981

  20. Beam dump experiment at future electron-positron colliders

    NASA Astrophysics Data System (ADS)

    Kanemura, Shinya; Moroi, Takeo; Tanabe, Tomohiko

    2015-12-01

    We propose a new beam dump experiment at future colliders with electron (e-) and positron (e+) beams, BDee, which will provide a new possibility to search for hidden particles, like hidden photon. If a particle detector is installed behind the beam dump, it can detect the signal of in-flight decay of the hidden particles produced by the scatterings of e± beams off materials for dumping. We show that, compared to past experiments, BDee (in particular BDee at e+e- linear collider) significantly enlarges the parameter region where the signal of the hidden particle can be discovered.

  1. Cross section measurements in the main injector particle production (FNAL-E907) experiment at 58 GeV energy

    SciTech Connect

    Gunaydin, Yusuf Oguzhan

    2009-12-01

    Cross-sections are presented for 58 GeV π, K, and p on a wide range of nuclear targets. These cross-sections are essential for determining the neutrino flux in measurements of neutrino cross-sections and oscillations. The E907 Main Injector Particle Production (MIPP) experiment at Fermilab is a fixed target experiment for measuring hadronic particle production using primary 120 GeV/c protons and secondary π, K, and p beams. The particle identification is made by dE/dx in a time projection chamber, and by time-of-flight, differential Cherenkov and ring imaging Cherenkov detectors, which together cover a wide range of momentum from 0.1 GeV/c up to 120 GeV/c. MIPP targets span the periodic table, from hydrogen to uranium, including beryllium and carbon. The MIPP has collected ~ 0.26 x 106 events of 58 GeV/c secondary particles produced by protons from the main injector striking a carbon target.

  2. FNAL-NICADD extruded scintillator

    SciTech Connect

    Beznosko, D.; Bross, A.; Dyshkant, A.; Pla-Dalmau, A.; Rykalin, V.; /Northern Illinois U.

    2005-09-01

    The possibility to produce a scintillator that satisfies the demands of physicists from different science areas has emerged with the installation of an extrusion line at Fermi National Accelerator Laboratory (FNAL). The extruder is the product of the fruitful collaboration between FNAL and Northern Illinois Center for Accelerator and Detector Development (NICADD) at Northern Illinois University (NIU). The results from the light output, light attenuation length and mechanical tolerance indicate that FNAL-NICADD scintillator is of high quality. Improvements in the extrusion die will yield better scintillator profiles and decrease the time needed for initial tuning. This paper will present the characteristics of the FNAL-NICADD scintillator based on the measurements performed. They include the response to MIPs from cosmic rays for individual extruded strips and irradiation studies where extruded samples were irradiated up to 1 Mrad. We will also discuss the results achieved with a new die design. The attractive perspective of using the extruded scintillator with MRS (Metal Resistive Semiconductor) photodetector readout will also be shown.

  3. Physics of leptoquarks in precision experiments and at particle colliders

    NASA Astrophysics Data System (ADS)

    Doršner, I.; Fajfer, S.; Greljo, A.; Kamenik, J. F.; Košnik, N.

    2016-06-01

    We present a comprehensive review of physics effects generated by leptoquarks (LQs), i.e., hypothetical particles that can turn quarks into leptons and vice versa, of either scalar or vector nature. These considerations include discussion of possible completions of the Standard Model that contain LQ fields. The main focus of the review is on those LQ scenarios that are not problematic with regard to proton stability. We accordingly concentrate on the phenomenology of light leptoquarks that is relevant for precision experiments and particle colliders. Important constraints on LQ interactions with matter are derived from precision low-energy observables such as electric dipole moments, (g - 2) of charged leptons, atomic parity violation, neutral meson mixing, Kaon, B, and D meson decays, etc. We provide a general analysis of indirect constraints on the strength of LQ interactions with the quarks and leptons to make statements that are as model independent as possible. We address complementary constraints that originate from electroweak precision measurements, top, and Higgs physics. The Higgs physics analysis we present covers not only the most recent but also expected results from the Large Hadron Collider (LHC). We finally discuss direct LQ searches. Current experimental situation is summarized and self-consistency of assumptions that go into existing accelerator-based searches is discussed. A progress in making next-to-leading order predictions for both pair and single LQ productions at colliders is also outlined.

  4. The FNAL Injector Upgrade Status

    SciTech Connect

    Tan, C.Y.; Bollinger, D.S.; Duel, K.L.; Karns, P.R.; Lackey, J.R.; Pellico, W.A; Scarpine, V.E.; Tomlin, R.E.; /Fermilab

    2012-05-14

    The new FNAL H{sup -} injector upgrade is currently being tested before installation in the Spring 2012 shutdown of the accelerator complex. This line consists of an H{sup -} source, low energy beam transport (LEBT), 200 MHz RFQ and medium energy beam transport (MEBT). Beam measurements have been performed to validate the design before installation. The results of the beam measurements are presented in this paper.

  5. Electropolishing at ANL/FNAL.

    SciTech Connect

    Kelly, M. P.; Gerbick, S. M.; Wu, G.; Bice, D.; Physics; FNAL

    2009-01-01

    A system for electropolishing of 1.3 GHz elliptical single- and nine-cell cavities is in operation at the joint ANL/FNAL cavity processing facility located at Argonne. The system is one peice of a larger 200 m2 complete single cavity processing and assembly facility which also includes clean rooms and high-pressure rinsing. Recently, the electropolishing system has been used to process a series of single and nine-cell cavities. For single cell cavities a good set of EP parameters has been demonstrated based on more than a half dozen complete processing and cold test cycles at ANL/FNAL. The lastest six single cell cavities each exceed EACC=35 MV/m and, at this gradient, have Q in the range 6 10{sup 9} - 1 10{sup 10}. The first nine cell cavities electropolished at ANL have not yet reached similar fields ({approx}23 MV/m-26 MV/m) and ongoing activities are focussed on demonstrating >30 MV/m in these cavities. Suitable nine cell EP parameters using the ANL/FNAL EP system including acid/water temperatures, flow rates, current, voltage, air flow etc. are all substantially different than for single-cell cavities and are discussed here.

  6. Fast timing and trigger Cherenkov detector for collider experiments

    NASA Astrophysics Data System (ADS)

    Grigoryev, V. A.; Kaplin, V. A.; Karavicheva, T. L.; Konevskikh, A. S.; Kurepin, A. B.; Loginov, V. A.; Melikyan, Yu A.; Morozov, I. V.; Reshetin, A. I.; Serebryakov, D. V.; Shabanov, A. I.; Slupecki, M.; Trzaska, W. H.; Tykmanov, E. M.

    2016-02-01

    Analysis of fast timing and trigger Cherenkov detector's design for its use in collider experiments is presented. Several specific requirements are taken into account - necessity of the radiator's placement as close to the beam pipe as possible along with the requirement of gapless (solid) radiator's design. Characteristics of the Cherenkov detector's laboratory prototype obtained using a pion beam at the CERN Proton Synchrotron are also presented, showing the possibility of obtaining sufficiently high geometrical efficiency along with good enough time resolution (50 ps sigma).

  7. Flavour physics and the Large Hadron Collider beauty experiment.

    PubMed

    Gibson, Valerie

    2012-02-28

    An exciting new era in flavour physics has just begun with the start of the Large Hadron Collider (LHC). The LHCb (where b stands for beauty) experiment, designed specifically to search for new phenomena in quantum loop processes and to provide a deeper understanding of matter-antimatter asymmetries at the most fundamental level, is producing many new and exciting results. It gives me great pleasure to describe a selected few of the results here-in particular, the search for rare B(0)(s)-->μ+ μ- decays and the measurement of the B(0)(s) charge-conjugation parity-violating phase, both of which offer high potential for the discovery of new physics at and beyond the LHC energy frontier in the very near future. PMID:22253243

  8. Optical injection using colliding laser pulses: experiments at LBNL

    NASA Astrophysics Data System (ADS)

    Leemans, W. P.; Geddes, C. G. R.; Toth, C.; Faure, J.; van Tilborg, J.; Marcelis, B.; Esarey, E.; Schroeder, C. B.; Fubiani, G.; Shadwick, B. A.; Dugan, G.; Cary, J.; Giacone, R.

    2002-11-01

    Laser driven acceleration in plasmas has succeeded in producing electron beams containing multi-nC's of charge, with some fraction of the electrons having energies in excess of 10's of MeV's but 100 % energy spread. One of the current challenges is to produce electron beams with much reduced energy spread. We report on experimental progress in the laser triggered injection of electrons in a laser wakefield accelerator using the colliding pulse method (E. Esarey et al., Phys. Rev. Lett. 79, 2682 (1997).), (C.B. Schroeder et al., Phys. Rev. E 59, 6037 (1999).). The experiments use the l'OASIS multi-beam 10 Hz high power Ti:Al_2O3 laser system (W.P. Leemans et al., Phys. Plasmas 8, 2510 (2001).). In the present experiments, two counter propagating beams (30^rc angle) are focused onto a high density gas jet. Preliminary results indicate that electron beam properties are affected by the second beam. Details of the experiments will be shown as well as comparisons with simulations.

  9. The Multi-Purpose Detector (MPD) of the collider experiment

    NASA Astrophysics Data System (ADS)

    Golovatyuk, V.; Kekelidze, V.; Kolesnikov, V.; Rogachevsky, O.; Sorin, A.

    2016-08-01

    The project NICA (Nuclotron-based Ion Collider fAcility) is aimed to study dense baryonic matter in heavy-ion collisions in the energy range up to √{s_{NN}} = 11 GeV with average luminosity of L = 1027 cm-2s-1 (for 197Au79). The experimental program at the NICA collider will be performed with the Multi-Purpose Detector (MPD). We report on the main physics objectives of the NICA heavy-ion program and present the main detector components.

  10. 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.

  11. Electron density and plasma dynamics of a colliding plasma experiment

    NASA Astrophysics Data System (ADS)

    Wiechula, J.; Schönlein, A.; Iberler, M.; Hock, C.; Manegold, T.; Bohlender, B.; Jacoby, J.

    2016-07-01

    We present experimental results of two head-on colliding plasma sheaths accelerated by pulsed-power-driven coaxial plasma accelerators. The measurements have been performed in a small vacuum chamber with a neutral-gas prefill of ArH2 at gas pressures between 17 Pa and 400 Pa and load voltages between 4 kV and 9 kV. As the plasma sheaths collide, the electron density is significantly increased. The electron density reaches maximum values of ≈8 ṡ 1015 cm-3 for a single accelerated plasma and a maximum value of ≈2.6 ṡ 1016 cm-3 for the plasma collision. Overall a raise of the plasma density by a factor of 1.3 to 3.8 has been achieved. A scaling behavior has been derived from the values of the electron density which shows a disproportionately high increase of the electron density of the collisional case for higher applied voltages in comparison to a single accelerated plasma. Sequences of the plasma collision have been taken, using a fast framing camera to study the plasma dynamics. These sequences indicate a maximum collision velocity of 34 km/s.

  12. Linear polarization of gluons and photons in unpolarized collider experiments

    SciTech Connect

    Pisano, Cristian; Boer, Daniël; Brodsky, Stanley J.; Buffing, Maarten G. A.; Mulders, Piet 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 pair 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.

  13. An overview of the new test stand for H⁻ ion sources at FNAL.

    PubMed

    Sosa, A; Bollinger, D S; Duel, K; Karns, P R; Pellico, W; Tan, C Y

    2016-02-01

    A new test stand at Fermi National Accelerator Laboratory (FNAL) is being constructed to carry out experiments to develop and upgrade the present magnetron-type sources of H(-) ions of up to 80 mA at 35 keV in the context of the Proton Improvement Plan. The aim of this plan is to provide high-power proton beams for the experiments at FNAL. The technical details of the construction and layout of this test stand are presented, along with a prospective set of diagnostics to monitor the sources. PMID:26931987

  14. The Next Linear Collider: NLC2001

    SciTech Connect

    D. Burke et al.

    2002-01-14

    Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider. A first Zeroth-Order Design Report (ZDR) [2] for a second-generation electron-positron linear collider, the Next Linear Collider (NLC), was published five years ago. The NLC design is based on a high-frequency room-temperature rf accelerator. Its goal is exploration of elementary particle physics at the TeV center-of-mass energy, while learning how to design and build colliders at still higher energies. Many advances in accelerator technologies and improvements in the design of the NLC have been made since 1996. This Report is a brief update of the ZDR.

  15. Effect of 3D Polarization profiles on polarization measurements and colliding beam experiments

    SciTech Connect

    Fischer, W.; Bazilevsky, A.

    2011-08-18

    The development of polarization profiles are the primary reason for the loss of average polarization. Polarization profiles have been parametrized with a Gaussian distribution. We derive the effect of 3-dimensional polarization profiles on the measured polarization in polarimeters, as well as the observed polarization and the figure of merit in single and double spin experiments. Examples from RHIC are provided. The Relativistic Heavy Ion Collider (RHIC) is the only collider of spin polarized protons. During beam acceleration and storage profiles of the polarization P develop, which affect the polarization measured in a polarimeter, and the polarization and figure of merit (FOM) in colliding beam experiments. We calculate these for profiles in all dimensions, and give examples for RHIC. Like in RHIC we call the two colliding beams Blue and Yellow. We use the overbar to designate intensity-weighted averages in polarimeters (e.g. {bar P}), and angle brackets to designate luminosity-weighted averages in colliding beam experiments (e.g.

    ).

  16. 2001 Report on the Next Linear Collider

    SciTech Connect

    Gronnberg, J; Breidenbach; Burke, D; Corlett, J; Dombeck, T; Markiewicz, T

    2001-08-28

    Recent studies in elementary particle physics have made the need for an e{sup +}e{sup -} linear collider able to reach energies of 500 GeV and above with high luminosity more compelling than ever [1]. Observations and measurements completed in the last five years at the SLC (SLAC), LEP (CERN), and the Tevatron (FNAL) can be explained only by the existence of at least one particle or interaction that has not yet been directly observed in experiment. The Higgs boson of the Standard Model could be that particle. The data point strongly to a mass for the Higgs boson that is just beyond the reach of existing colliders. This brings great urgency and excitement to the potential for discovery at the upgraded Tevatron early in this decade, and almost assures that later experiments at the LHC will find new physics. But the next generation of experiments to be mounted by the world-wide particle physics community must not only find this new physics, they must find out what it is. These experiments must also define the next important threshold in energy. The need is to understand physics at the TeV energy scale as well as the physics at the 100-GeV energy scale is now understood. This will require both the LHC and a companion linear electron-positron collider.

  17. Fourth workshop on Experiments and Detectors for a Relativistic Heavy Ion Collider

    NASA Technical Reports Server (NTRS)

    Fatyga, M. (Editor); Moskowitz, B. (Editor)

    1992-01-01

    We present a description of an experiment which can be used to search for effects of strong electromagnetic fields on the production of e(sup +) e(sup -) pairs in the elastic scattering of two heavy ions at the Relativistic Heavy Ion Collider (RHIC). A very brief discussion of other possible studies of electromagnetic phenomena at RHIC is also presented.

  18. Overview of results from the Fermilab fixed target and collider experiments

    SciTech Connect

    Montgomery, H.E.

    1997-06-01

    In this paper we present a review of recent QCD related results from Fermilab fixed target and collider experiments. Topics covered range from structure functions through W/Z production, heavy quark production and jet angular distributions. We also include the current state of knowledge about leptoquark pair production in hadronic collisions.

  19. SNiPER: an offline software framework for non-collider physics experiments

    NASA Astrophysics Data System (ADS)

    Zou, J. H.; Huang, X. T.; Li, W. D.; Lin, T.; Li, T.; Zhang, K.; Deng, Z. Y.; Cao, G. F.

    2015-12-01

    SNiPER (Software for Non-collider Physics ExpeRiments) has been developed based on common requirements from both nuclear reactor neutrino and cosmic ray experiments. The design and implementation of SNiPER is described in this proceeding. Compared to the existing offline software frameworks in the high energy physics domain, the design of SNiPER is more focused on execution efficiency and flexibility. SNiPER has an open structure. User applications are executed as plug-ins based on it. The framework contains a compact kernel for software components management, event execution control, job configuration, common services, etc. Some specific features are attractive to non-collider physics experiments.

  20. Transition Radiation Detector in the D0 colliding beam experiment at Fermilab

    SciTech Connect

    Piekarz, H.

    1995-04-01

    The construction, operation and response of the Transition Radiation Detector (TRD) at DO colliding beam experiment at Fermilab are presented. The use of the TRD signal to enhance electron identification and hadronic rejection in the multiparticle background characteristic for the antiproton-proton interactions at the center-of-mass energy of 1.8 TeV is also described and results are discussed.

  1. Numerical modeling of laser-driven experiments of colliding jets: Turbulent amplification of seed magnetic fields

    NASA Astrophysics Data System (ADS)

    Tzeferacos, Petros; Fatenejad, Milad; Flocke, Norbert; Graziani, Carlo; Gregori, Gianluca; Lamb, Donald; Lee, Dongwook; Meinecke, Jena; Scopatz, Anthony; Weide, Klaus

    2014-10-01

    In this study we present high-resolution numerical simulations of laboratory experiments that study the turbulent amplification of magnetic fields generated by laser-driven colliding jets. The radiative magneto-hydrodynamic (MHD) simulations discussed here were performed with the FLASH code and have assisted in the analysis of the experimental results obtained from the Vulcan laser facility. In these experiments, a pair of thin Carbon foils is placed in an Argon-filled chamber and is illuminated to create counter-propagating jets. The jets carry magnetic fields generated by the Biermann battery mechanism and collide to form a highly turbulent region. The interaction is probed using a wealth of diagnostics, including induction coils that are capable of providing the field strength and directionality at a specific point in space. The latter have revealed a significant increase in the field's strength due to turbulent amplification. Our FLASH simulations have allowed us to reproduce the experimental findings and to disentangle the complex processes and dynamics involved in the colliding flows. This work was supported in part at the University of Chicago by DOE NNSA ASC.

  2. Laboratory Magnetic Reconnection Experiments with Colliding, Magnetized Laser-Produced Plasma Plumes

    NASA Astrophysics Data System (ADS)

    Fox, W. R., II; Bhattacharjee, A.; Deng, W.; Moissard, C.; Germaschewski, K.; Fiksel, G.; Barnak, D.; Chang, P. Y.; Hu, S.; Nilson, P.

    2014-12-01

    We present results from experiments and simulations of magnetic reconnection between colliding plumes of laser-produced plasma. In the experiments, which open up a new experimental regime for reconnection study, bubbles of high-temperature, high-density plasma are created by focusing lasers down to sub-millimeter-scale spots on a plastic or metal foil, ionizing the foil into hemispherical bubbles that expand supersonically off the surface of the foil. If multiple bubbles are created at small separation, the bubbles expand into one another, and the embedded magnetic fields (either self-generated or externally imposed) are squeezed together and reconnect. We will review recent experiments, which have observed magnetic field annihilation, outflow jets, particle energization, and the formation of elongated current sheets. We compare the results against experiments with unmagnetized plumes, which observe the Weibel instability as the two plumes collide and interact. Particle-in-cell simulations of the strongly driven reconnection in these experiments show fast reconnection due to two-fluid effects, flux pile-up, and plasmoid formation, and show particle energization by reconnection.

  3. Laboratory experiments on cluster/aerosol formation by colliding ablation plumes

    NASA Astrophysics Data System (ADS)

    Hirooka, Y.; Tanaka, K. A.; Sato, H.; Ishihara, K.; Sunahara, A.

    2010-08-01

    First-of-a-kind experiments on cluster/aerosol formation by colliding ablation plumes have been conducted, radiating Al, Cu and C with 3ω-YAG laser at power densities between 2~30 J/cm2/pulse. Visible spectroscopy indicates that the excitation light intensities of Cu and Al plumes are not necessarily be doubled in collision, but can rather be weakened due to atomic and molecular reactions. For colliding C plumes, Swan band radiation has been observed, indicative of C2 and/or C2+ formation, and ion mass spectrometry has identified Cn+-clusters, including C+, C2+, C3+, C4+ and C5+. From ICCD camera observations, C plumes generated at power densities above ~15 J/cm2/pulse tend to split into two components with respective velocities, only the slow component of which appears to be interactive to form clusters. Nano structures like CNT have been identified in deposits from colliding C plumes.

  4. Nucleon Decay and Neutrino Experiments, Experiments at High Energy Hadron Colliders, and String Theor

    SciTech Connect

    Jung, Chang Kee; Douglas, Michaek; Hobbs, John; McGrew, Clark; Rijssenbeek, Michael

    2013-07-29

    This is the final report of the DOE grant DEFG0292ER40697 that supported the research activities of the Stony Brook High Energy Physics Group from November 15, 1991 to April 30, 2013. During the grant period, the grant supported the research of three Stony Brook particle physics research groups: The Nucleon Decay and Neutrino group, the Hadron Collider Group, and the Theory Group.

  5. A new micro-strip tracker for the new generation of experiments at hadron colliders

    SciTech Connect

    Dinardo, Mauro E

    2005-12-01

    This thesis concerns the development and characterization of a prototype Silicon micro-strip detector that can be used in the forward (high rapidity) region of a hadron collider. These detectors must operate in a high radiation environment without any important degradation of their performance. The innovative feature of these detectors is the readout electronics, which, being completely data-driven, allows for the direct use of the detector information at the lowest level of the trigger. All the particle hits on the detector can be readout in real-time without any external trigger and any particular limitation due to dead-time. In this way, all the detector information is available to elaborate a very selective trigger decision based on a fast reconstruction of tracks and vertex topology. These detectors, together with the new approach to the trigger, have been developed in the context of the BTeV R&D program; our aim was to define the features and the design parameters of an optimal experiment for heavy flavour physics at hadron colliders. Application of these detectors goes well beyond the BTeV project and, in particular, involves the future upgrades of experiments at hadron colliders, such as Atlas, CMS and LHCb. These experiments, indeed, are already considering for their future high-intensity runs a new trigger strategy a la BTeV. Their aim is to select directly at trigger level events containing Bhadrons, which, on several cases, come from the decay of Higgs bosons, Z{sup o}'s or W{sup {+-}}'s; the track information can also help on improving the performance of the electron and muon selection at the trigger level. For this reason, they are going to develop new detectors with practically the same characteristics as those of BTeV. To this extent, the work accomplished in this thesis could serve as guide-line for those upgrades.

  6. DELPHES 3: a modular framework for fast simulation of a generic collider experiment

    NASA Astrophysics Data System (ADS)

    de Favereau, J.; Delaere, C.; Demin, P.; Giammanco, A.; Lemaître, V.; Mertens, A.; Selvaggi, M.

    2014-02-01

    The version 3.0 of the Delphes fast-simulation is presented. The goal of Delphes is to allow the simulation of a multipurpose detector for phenomenological studies. The simulation includes a track propagation system embedded in a magnetic field, electromagnetic and hadron calorimeters, and a muon identification system. Physics objects that can be used for data analysis are then reconstructed from the simulated detector response. These include tracks and calorimeter deposits and high level objects such as isolated electrons, jets, taus, and missing energy. The new modular approach allows for greater flexibility in the design of the simulation and reconstruction sequence. New features such as the particle-flow reconstruction approach, crucial in the first years of the LHC, and pile-up simulation and mitigation, which is needed for the simulation of the LHC detectors in the near future, have also been implemented. The Delphes framework is not meant to be used for advanced detector studies, for which more accurate tools are needed. Although some aspects of Delphes are hadron collider specific, it is flexible enough to be adapted to the needs of electron-positron collider experiments. [Figure not available: see fulltext.

  7. Ion colliders

    SciTech Connect

    Fischer, W.

    2011-12-01

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the

  8. Colliding pulse injection experiments in non-collinear geometryfor controlled laser plasma wakefield acceleration of electrons

    SciTech Connect

    Toth, Carl B.; Esarey, Eric H.; Geddes, Cameron G.R.; Leemans,Wim P.; Nakamura, Kei; Panasenko, Dmitriy; Schroeder, Carl B.; Bruhwiler,D.; Cary, J.R.

    2007-06-25

    An optical injection scheme for a laser-plasma basedaccelerator which employs a non-collinear counter-propagating laser beamto push background electrons in the focusing and acceleration phase viaponderomotive beat with the trailing part of the wakefield driver pulseis discussed. Preliminary experiments were performed using a drive beamof a_0 = 2.6 and colliding beam of a_1 = 0.8 both focused on the middleof a 200 mu m slit jet backed with 20 bar, which provided ~; 260 mu mlong gas plume. The enhancement in the total charge by the collidingpulse was observed with sharp dependence on the delay time of thecolliding beam. Enhancement of the neutron yield was also measured, whichsuggests a generation of electrons above 10 MeV.

  9. Capture cavity II results at FNAL

    SciTech Connect

    Branlard, Julien; Chase, Brian; Cancelo, G.; Carcagno, R.; Edwards, H.; Fliller, R.; Hanna, B.; Harms, Elvan; Hocker, A.; Koeth, T.; Kucera, M.; /Fermilab

    2007-06-01

    As part of the research and development towards the International Linear Collider (ILC), several test facilities have been developed at Fermilab. This paper presents the latest Low Level RF (LLRF) results obtained with Capture Cavity II (CCII) at the ILC Test Accelerator (ILCTA) test facility. The main focus will be on controls and RF operations using the SIMCON based LLRF system developed in DESY [1]. Details about hardware upgrades and future work will be discussed.

  10. Recent results from the CDF (Collider Detector at Fermilab) experiment at the Tevatron proton-antiproton collider

    SciTech Connect

    Geer, S. . High Energy Physics Lab.)

    1989-09-01

    Recent results from the CDF experiment are described. The Standard Model gives a good description of jet production, and W/Z production and decay. There is no evidence yet for the top quark, for fourth generation quarks, or for deviations from the Standard Model ascribable to quark substructure, supersymmetric particles, or heavy additional W-like or Z-like bosons. Limits are given where applicable. A search for a light Higgs Boson is also described. 11 refs., 24 figs.

  11. Development of a forward calorimeter system for the STAR experiment

    NASA Astrophysics Data System (ADS)

    Tsai, O. D.; Aschenauer, E.; Christie, W.; Dunkelberger, L. E.; Fazio, S.; Gagliardi, C. A.; Heppelmann, S.; Huang, H. Z.; Jacobs, W. W.; Igo, G.; Kisilev, A.; Landry, K.; Liu, X.; Mondal, M. M.; Pan, Y. X.; Sergeeva, M.; Shah, N.; Sichtermann, E.; Trentalange, S.; Visser, G.; Wissink, S.

    2015-02-01

    We present results of an R&D program to develop a forward calorimeter system (FCS) for the STAR experiment at the Relativistic Heavy Ion Collider at BNL. The FCS is a very compact, compensated, finely granulated, high resolution calorimeter system being developed for p+p and p+A program at RHIC. The FCS prototype consists of both electromagnetic and hadron calorimeters. The electromagnetic portion of the detector is constructed with W powder and scintillation fibers. The hadronic calorimeter is a traditional Pb/Sc-plate sandwich design. Both calorimeters were readout with Hamamatsu MPPCs. A full- scale prototype of the FCS was tested with a beam at FNAL in March 2014. We present details of the design, construction technique and performance of the FCS prototype during the test run at FNAL.

  12. Issues and experience with controlling beam loss at the Tevatron collider

    SciTech Connect

    Annala, Gerald; /Fermilab

    2007-07-01

    Controlling beam loss in the Tevatron collider is of great importance because of the delicate nature of the cryogenic magnet system and the collider detectors. Maximizing the physics potential requires optimized performance as well as protection of all equipment. The operating history of the Tevatron has significantly influenced the way losses are managed. The development of beam loss management in the Tevatron will be presented.

  13. OPERATIONS ELECTRONIC LOGBOOK EXPERIENCE AT BNL.

    SciTech Connect

    SATOGATA,T.; CAMPBELL,I.; MARR,G.; SAMPSON,P.

    2002-06-02

    A web-based system for electronic logbooks, ''elog'', developed at Fermilab (FNAL), has been adopted for use by AGS and RHIC operations and physicists at BNL for the 2001-2 fixed target and collider runs. This paper describes the main functional and technical issues encountered in the first year of electronic logbook use, including security, search and indexing, sequencer integration, archival, and graphics management. We also comment on organizational experience and planned changes for the next facility run starting in September 2002.

  14. Experimental characterization of a coaxial plasma accelerator for a colliding plasma experiment

    NASA Astrophysics Data System (ADS)

    Wiechula, J.; Hock, C.; Iberler, M.; Manegold, T.; Schönlein, A.; Jacoby, J.

    2015-04-01

    We report experimental results of a single coaxial plasma accelerator in preparation for a colliding plasma experiment. The utilized device consisted of a coaxial pair of electrodes, accelerating the plasma due to J ×B forces. A pulse forming network, composed of three capacitors connected in parallel, with a total capacitance of 27 μF was set up. A thyratron allowed to switch the maximum applied voltage of 9 kV. Under these conditions, the pulsed currents reached peak values of about 103 kA. The measurements were performed in a small vacuum chamber with a neutral-gas prefill at gas pressures between 10 Pa and 14 000 Pa. A gas mixture of ArH2 with 2.8% H2 served as the discharge medium. H2 was chosen in order to observe the broadening of the Hβ emission line and thus estimate the electron density. The electron density for a single plasma accelerator reached peak values on the order of 1016 cm-3 . Electrical parameters, inter alia inductance and resistance, were determined for the LCR circuit during the plasma acceleration as well as in a short circuit case. Depending on the applied voltage, the inductance and resistance reached values ranging from 194 nH to 216 nH and 13 mΩ to 23 mΩ, respectively. Furthermore, the plasma velocity was measured using a fast CCD camera. Plasma velocities of 2 km/s up to 17 km/s were observed, the magnitude being highly correlated with gas pressure and applied voltage.

  15. Experimental characterization of a coaxial plasma accelerator for a colliding plasma experiment

    SciTech Connect

    Wiechula, J.; Hock, C.; Iberler, M.; Manegold, T.; Schönlein, A.; Jacoby, J.

    2015-04-15

    We report experimental results of a single coaxial plasma accelerator in preparation for a colliding plasma experiment. The utilized device consisted of a coaxial pair of electrodes, accelerating the plasma due to J×B forces. A pulse forming network, composed of three capacitors connected in parallel, with a total capacitance of 27 μF was set up. A thyratron allowed to switch the maximum applied voltage of 9 kV. Under these conditions, the pulsed currents reached peak values of about 103 kA. The measurements were performed in a small vacuum chamber with a neutral-gas prefill at gas pressures between 10 Pa and 14 000 Pa. A gas mixture of ArH{sub 2} with 2.8% H{sub 2} served as the discharge medium. H{sub 2} was chosen in order to observe the broadening of the H{sub β} emission line and thus estimate the electron density. The electron density for a single plasma accelerator reached peak values on the order of 10{sup 16} cm{sup −3}. Electrical parameters, inter alia inductance and resistance, were determined for the LCR circuit during the plasma acceleration as well as in a short circuit case. Depending on the applied voltage, the inductance and resistance reached values ranging from 194 nH to 216 nH and 13 mΩ to 23 mΩ, respectively. Furthermore, the plasma velocity was measured using a fast CCD camera. Plasma velocities of 2 km/s up to 17 km/s were observed, the magnitude being highly correlated with gas pressure and applied voltage.

  16. Control system for BCP processing facility at FNAL

    SciTech Connect

    Cristian Boffo et al.

    2003-09-11

    The surface processing is one of the key elements of superconducting RF cavity fabrication. Safety and reliability are the main requirements for the chemical surface treatment facility being developed at FNAL. Accepting the Buffered Chemical Polishing (BCP) as the baseline process, a ''gravity feed and open etching tank'' approach has been chosen at this stage. This choice resulted in the introduction of a control system with a strong automation since the number of elements to be controlled at different steps of the process is rather big. In order to allow for maximum flexibility, two operational modes were defined within the control system: semi-automatic, which requires an operator's decision to move from one stage to another, and manual. This paper describes the main features of the control system for the BCP facility that is under development at FNAL.

  17. Beam dynamics studies of the 8 GeV Linac at FNAL

    SciTech Connect

    Ostroumov, P.N.; Mustapha, B.; Carneiro, J.-P.; /Fermilab

    2008-11-01

    The proposed 8-GeV proton driver (PD) linac at FNAL includes a front end up to {approx}420 MeV operating at 325 MHz and a high energy section at 1300 MHz. A normal conducting RFQ and short CH type resonators are being developed for the initial acceleration of the H-minus or proton beam up to 10 MeV. From 10 MeV to {approx}420 MeV, the voltage gain is provided by superconducting (SC) spoke-loaded cavities. In the high-energy section, the acceleration will be provided by the International Linear Collider (ILC)-style SC elliptical cell cavities. To employ existing, readily available klystrons, an RF power fan out from high-power klystrons to multiple cavities is being developed. The beam dynamics simulation code TRACK, available in both serial and parallel versions, has been updated to include all known H-minus stripping mechanisms to predict the exact location of beam losses. An iterative simulation procedure is being developed to interact with a transient beam loading model taking into account RF feedback and feedforward systems.

  18. K (transverse) jet algorithms in hadron colliders: The D0 experience

    SciTech Connect

    V. Daniel Elvira

    2002-12-05

    D0 has implemented and studied a k{sub {perpendicular}} jet algorithm for the first time in a hadron collider. The authors have submitted two physics results for publication: the subjet multiplicity in quark and gluon jets and the central inclusive jet cross section measurements. A third result, a measurement of thrust distributions in jet events, is underway. A combination of measurements using several types of algorithms and samples taken at different center-of-mass energies is desirable to understand and distinguish with higher accuracy between instrumentation and physics effects.

  19. An AGS experiment to test bunching for the proton driver of the muon collider.

    SciTech Connect

    Norem, J.

    1998-04-27

    The proton driver for the muon collider must produce short pulses of protons in order to facilitate muon cooling and operation with polarized beams. In order to test methods of producing these bunches they have operated the AGS near transition and studied procedures which involved moving the transition energy {gamma} to the beam energy. They were able to produce stable bunches with RMS widths of {sigma} = 2.2-2.7 ns for longitudinal bunch areas of {minus}1.5 V-s, in addition to making measurements of the lowest two orders of the momentum compaction factor.

  20. Operation of the DC current transformer intensity monitors at FNAL during run II

    SciTech Connect

    Crisp, J.; Fellenz, B.; Heikkinen, D.; Ibrahim, M.A.; Meyer, T.; Vogel, G.; /Fermilab

    2012-01-01

    Circulating beam intensity measurements at FNAL are provided by five DC current transformers (DCCT), one per machine. With the exception of the DCCT in the Recycler, all DCCT systems were designed and built at FNAL. This paper presents an overview of both DCCT systems, including the sensor, the electronics, and the front-end instrumentation software, as well as their performance during Run II.

  1. 15 Years of R&D on High Field Accelerator Magnets at FNAL

    SciTech Connect

    Barzi, Emanuela; Zlobin, Alexander V.

    2015-12-10

    The High Field Magnet (HFM) Program at Fermi National Accelerator Laboratory (FNAL) has been developing Nb3Sn superconducting magnets, materials and technologies for present and future particle accelerators since the late 1990s. This paper summarizes the main results of the Nb3Sn accelerator magnet and superconductor R&D at FNAL and outlines the Program next steps.

  2. 15 Years of R&D on high field accelerator magnets at FNAL

    DOE PAGESBeta

    Barzi, Emanuela; Zlobin, Alexander V.

    2016-07-01

    The High Field Magnet (HFM) Program at Fermi National Accelerator Laboratory (FNAL) has been developing Nb3Sn superconducting magnets, materials and technologies for present and future particle accelerators since the late 1990s. This paper summarizes the main results of the Nb3Sn accelerator magnet and superconductor R&D at FNAL and outlines the Program next steps.

  3. Exotic colliders

    SciTech Connect

    Chattopadhyay, S.

    1994-11-01

    The motivation, feasibility and potential for two unconventional collider concepts - the Gamma-Gamma Collider and the Muon Collider - are described. The importance of the development of associated technologies such as high average power, high repetition rate lasers and ultrafast phase-space techniques are outlined.

  4. Photon Colliders

    SciTech Connect

    Gronberg, J

    2002-10-07

    A photon collider interaction region has the possibility of expanding the physics reach of a future TeV scale electron-positron collider. A survey of ongoing efforts to design the required lasers and optics to create a photon collider is presented in this paper.

  5. A new solid state extractor pulser for the FNAL magnetron ion source

    SciTech Connect

    Bollinger, D. S.; Lackey, J.; Larson, J.; Triplett, K.

    2015-10-05

    A new solid state extractor pulser has been installed on the Fermi National Accelerator Laboratory (FNAL) magnetron ion source, replacing a vacuum tube style pulser that was used for over 40 years. The required ion source extraction voltage is 35 kV for injection into the radio frequency quadrupole. At this voltage, the old pulser had a rise time of over 150 μs due to the current limit of the vacuum tube. The new solid state pulsers are capable of 50 kV, 100 A peak current pulses and have a rise time of 9 μs when installed in the operational system. This paper will discuss the pulser design and operational experience to date.

  6. A new solid state extractor pulser for the FNAL magnetron ion source

    NASA Astrophysics Data System (ADS)

    Bollinger, D. S.; Lackey, J.; Larson, J.; Triplett, K.

    2016-02-01

    A new solid state extractor pulser has been installed on the Fermi National Accelerator Laboratory (FNAL) magnetron ion source, replacing a vacuum tube style pulser that was used for over 40 years. The required ion source extraction voltage is 35 kV for injection into the radio frequency quadrupole. At this voltage, the old pulser had a rise time of over 150 μs due to the current limit of the vacuum tube. The new solid state pulsers are capable of 50 kV, 100 A peak current pulses and have a rise time of 9 μs when installed in the operational system. This paper will discuss the pulser design and operational experience to date.

  7. A New Chicane Experiment In PEP-II to Test Mitigations of the Electron Cloud Effect for Linear Colliders

    SciTech Connect

    Pivi, M.T.F.; Ng, J.S.T.; Arnett, D.; Cooper, F.; Kharakh, D.; King, F.K.; Kirby, R.E.; Kuekan, B.; Lipari, J.J.; Munro, M.; Olszewski, J.; Raubenheimer, T.O.; Seeman, J.; Smith, B.; Spencer, C.M.; Wang, L.; Wittmer, W.; Celata, C.M.; Furman, M.A.; /SLAC /LBL, Berkeley

    2008-07-03

    Beam instability caused by the electron cloud has been observed in positron and proton storage rings, and it is expected to be a limiting factor in the performance of future colliders [1-3]. The effect is expected to be particularly severe in magnetic field regions. To test possible mitigation methods in magnetic fields, we have installed a new 4-dipole chicane experiment in the PEP-II Low Energy Ring (LER) at SLAC with both bare and TiN-coated aluminum chambers. In particular, we have observed a large variation of the electron flux at the chamber wall as a function of the chicane dipole field. We infer this is a new high order resonance effect where the energy gained by the electrons in the positron beam depends on the phase of the electron cyclotron motion with respect to the bunch crossing, leading to a modulation of the secondary electron production. Presumably the cloud density is modulated as well and this resonance effect could be used to reduce its magnitude in future colliders. We present the experimental results obtained during January 2008 until the April final shut-down of the PEP-II machine.

  8. A New Chicane Experiment in PEP-II to Test Mitigations of the Electron Cloud Effect for Linear Colliders

    SciTech Connect

    Pivi, M. T.; Pivi, M.T.F.; Ng, J.S.T.; Arnett, D.; Cooper, F.; Kharakh, D.; King, F.K.; Kirby, R.E.; Kuekan, B.; Lipari, J.J.; Munro, M.; Olszewski, J.; Raubenheimer, T.O.; Seeman, J.; Spencer, C.M.; Wang, L.; Wittmer, W.; Celata, C.M.; Furman, M.A.; Smith, B.

    2008-06-11

    Beam instability caused by the electron cloud has been observed in positron and proton storage rings, and it is expected to be a limiting factor in the performance of future colliders [1-3]. The effect is expected to be particularly severe in magnetic field regions. To test possible mitigation methods in magnetic fields, we have installed a new 4-dipole chicane experiment in the PEP-II Low Energy Ring (LER) at SLAC with both bare and TiN-coated aluminum chambers. In particular, we have observed a large variation of the electron flux at the chamber wall as a function of the chicane dipole field. We infer this is a new high order resonance effect where the energy gained by the electrons in the positron beam depends on the phase of the electron cyclotron motion with respect to the bunch crossing, leading to a modulation of the secondary electron production. Presumably the cloud density is modulated as well and this resonance effect could be used to reduce its magnitude in future colliders. We present the experimental results obtained during January 2008 until the April final shut-down of the PEP-II machine.

  9. Muon collider progress

    SciTech Connect

    Noble, Robert J. FNAL

    1998-08-01

    Recent progress in the study of muon colliders is presented. An international collaboration consisting of over 100 individuals is involved in calculations and experiments to demonstrate the feasibility of this new type of lepton collider. Theoretical efforts are now concentrated on low-energy colliders in the 100 to 500 GeV center-of-mass energy range. Credible machine designs are emerging for much of a hypothetical complex from proton source to the final collider. Ionization cooling has been the most difficult part of the concept, and more powerful simulation tools are now in place to develop workable schemes. A collaboration proposal for a muon cooling experiment has been presented to the Fermilab Physics Advisory Committee, and a proposal for a targetry and pion collection channel experiment at Brookhaven National Laboratory is in preparation. Initial proton bunching and space-charge compensation experiments at existing hadron facilities have occurred to demonstrate proton driver feasibility.

  10. High-performance DIRC detector for the future Electron Ion Collider experiment

    NASA Astrophysics Data System (ADS)

    Kalicy, G.; Allison, L.; Cao, T.; Dzhygadlo, R.; Horn, T.; Hyde, C.; Ilieva, Y.; Nadel-Turonski, P.; Park, K.; Peters, K.; Schwarz, C.; Schwiening, J.; Stevens, J.; Xi, W.; Zorn, C.

    2016-07-01

    A radially-compact subsystem providing particle identification (e/π, π/K, K/p) over a wide momentum range is an essential requirement for the central detector of an Electron-Ion Collider (EIC). With a radial size of only a few cm, a detector based on Detection of Internally Reflected Cherenkov light (DIRC) principle is a very attractive solution. The R&D undertaken by the EIC PID consortium achieved the goal of showing feasibility of a high-performance DIRC that would extend the momentum coverage well beyond state-of-the-art allowing 3σ separation of π/K up to 6 GeV/c, e/K up to 1.8 GeV/c and p/K up to 10 GeV/c. A key component to reach such a performance is a special 3-layer spherical compound lens. This article describes the status of the design and R&D for the DIRC at EIC detector, with a focus on the detailed Monte Carlo simulation results for the high-performance DIRC.

  11. Development of Large Area Gas Electron Multiplier Detector and Its Application to a Digital Hadron Calorimeter for Future Collider Experiments

    SciTech Connect

    Yu, Jaehoon; White, Andrew

    2014-09-25

    The UTA High Energy Physics Group conducted generic detector development based on large area, very thin and high sensitivity gas detector using gas electron multiplier (GEM) technology. This is in preparation for a use as a sensitive medium for sampling calorimeters in future collider experiments at the Energy Frontier as well as part of the tracking detector in Intensity Frontier experiments. We also have been monitoring the long term behavior of one of the prototype detectors (30cmx30cm) read out by the SLAC-developed 13-bit KPiX analog chip over three years and have made presentations of results at various APS meetings. While the important next step was the development of large area (1m x 1m) GEM planes, we also have looked into opportunities of applying this technology to precision tracking detectors to significantly improve the performance of the Range Stack detector for CP violation experiments and to provide an amplification layer for the liquid Argon Time Projection Chamber in the LBNE experiment. We have jointly developed 33cmx100cm large GEM foils with the CERN gas detector development group to construct 33cm x100cm unit chambers. Three of these unit chambers will be put together to form a 1m x 1m detector plane. Following characterization of one 33cmx100cm unit chamber prototype, a total of five 1m x 1m planes will be constructed and inserted into an existing 1m3 RPC DHCAL stack to test the performance of the new GEM DHCAL in particle beams. The large area GEM detector we planned to develop in this proposal not only gives an important option to DHCAL for future collider experiments but also the potential to expand its use to Intensity Frontier and Cosmic Frontier experiments as high efficiency, high amplification anode planes for liquid Argon time projection chambers. Finally, thanks to its sensitivity to X-rays and other neutral radiations and its light-weight characteristics, the large area GEM has a great potential for the use in medical imaging and

  12. Design Concept and Parameters of a 15 T $Nb_{3}Sn$ Dipole Demonstrator for a 100 TEV Hadron Collider

    SciTech Connect

    Zlobin, A. V.; Andreev, N.; Barzi, E.; Kashikhin, V. V.; Novitski, I.

    2015-06-01

    FNAL has started the development of a 15 T $Nb_{3}Sn$ dipole demonstrator for a 100 TeV scale hadron collider. This paper describes the design concept and parameters of the 15 T $Nb_{3}Sn$ dipole demonstrator. The dipole magnetic, mechanical and quench protection concept and parameters are presented and discussed.

  13. Muon colliders

    SciTech Connect

    Palmer, R.B. |; Sessler, A.; Skrinsky, A.

    1996-01-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should thus be regarded as complementary. Parameters are given of 4 TeV and 0.5 TeV high luminosity {micro}{sup +}{micro}{sup {minus}}colliders, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders, starting from the proton accelerator needed to generate the muons and proceeding through muon cooling, acceleration and storage in a collider ring. Problems of detector background are also discussed.

  14. When Rubrics Collide: One Undergraduate Writing Tutor's Experience Negotiating Faculty and Institutional Assessments

    ERIC Educational Resources Information Center

    Martin, Kelli

    2013-01-01

    This article recounts one undergraduate writing tutor's experience helping a fellow peer navigate an institutional assessment rubric that seemed to contrast the assessment criteria provided by the student's instructor. This article presents a reflection on that experience, framed by Hutchings, Huber, and Ciccone's (2011) work on…

  15. A search for B_S0 oscillations at the Tevatron collider experiment D0

    SciTech Connect

    Krop, Dan N.; /Indiana U.

    2007-04-01

    We present a search for B{sub S}{sup 0} oscillations using semileptonic B{sub S} {yields} D{sub s}{mu}X (D{sub S} {yields} K{sub S}{sup 0}K). The data were collected using the D0 detector from events produced in {radical}s = 1.96 TeV proton-antiproton collisions at the Fermilab Tevatron. The Tevatron is currently the only place in the world that produces B{sub S}{sup 0} mesons and will be until early 2008 when the Large Hadron Collider begins operating at CERN. One of the vital ingredients for the search for B s oscillations is the determination of the flavor of the B{sub S}{sup 0} candidate (B{sub S}{sup 0} or {bar B}{sub S}{sup 0} ) at the time of its production, called initial state flavor tagging. We develop an likelihood based initial state flavor tagger that uses objects on the side of the event opposite to the reconstructed B meson candidate. To improve the performance of this flavor tagger, we have made it multidimensional so that it takes correlations between discriminants into account. This tagging is then certified by applying it to sample of semimuonic B{sup (0,+)} decays and measuring the well-known oscillation frequency {delta}m{sub d}. We obtain {delta}m{sub d} = 0.486 {+-} 0.021 ps{sup -1}, consistent with the world average. The tagging performance is characterized by the effective efficiency, {epsilon}D{sup 2} = (1.90 {+-} 0.41)%. We then turn to the search for B{sub S}{sup 0} oscillations in the above-named channel. A special two-dimensional mass fitting procedure is developed to separate kinematic reflections from signal events. Using this mass fitting procedure in an unbinned likelihood framework, we obtain a 95% C.L. of {Delta}m{sub s} > 1.10 ps{sup -1} and a sensitivity of 1.92 ps-1. This result is combined with other analyzed B{sub S}{sup 0} decay channels at D0 to obtain a combined 95% C.L. of {Delta}m{sub s} > 14.9 ps-1 and a sensitivity of 16.5 ps-1. The corresponding log likelihood scan has a preferred value of {Delta}m{sub s} = 19 ps-1

  16. When Worlds Collide: Identity, Culture and the Lived Experiences of Research When "Teaching-Led"

    ERIC Educational Resources Information Center

    Sharp, John G.; Hemmings, Brian; Kay, Russell; Callinan, Carol

    2015-01-01

    This article presents detailed findings from the qualitative or interpretive phase of a mixed-methods case study focusing on the professional identities and lived experiences of research among six lecturers working in different capacities across the field of education in a "teaching-led" higher education institution. Building upon the…

  17. PHENIX Conceptual Design Report. An experiment to be performed at the Brookhaven National Laboratory Relativistic Heavy Ion Collider

    SciTech Connect

    Nagamiya, Shoji; Aronson, Samuel H.; Young, Glenn R.; Paffrath, Leo

    1993-01-29

    The PHENIX Conceptual Design Report (CDR) describes the detector design of the PHENIX experiment for Day-1 operation at the Relativistic Heavy Ion Collider (RHIC). The CDR presents the physics capabilities, technical details, cost estimate, construction schedule, funding profile, management structure, and possible upgrade paths of the PHENIX experiment. The primary goals of the PHENIX experiment are to detect the quark-gluon plasma (QGP) and to measure its properties. Many of the potential signatures for the QGP are measured as a function of a well-defined common variable to see if any or all of these signatures show a simultaneous anomaly due to the formation of the QGP. In addition, basic quantum chromodynamics phenomena, collision dynamics, and thermodynamic features of the initial states of the collision are studied. To achieve these goals, the PHENIX experiment measures lepton pairs (dielectrons and dimuons) to study various properties of vector mesons, such as the mass, the width, and the degree of yield suppression due to the formation of the QGP. The effect of thermal radiation on the continuum is studied in different regions of rapidity and mass. The e{mu} coincidence is measured to study charm production, and aids in understanding the shape of the continuum dilepton spectrum. Photons are measured to study direct emission of single photons and to study {pi}{sup 0} and {eta} production. Charged hadrons are identified to study the spectrum shape, production of antinuclei, the {phi} meson (via K{sup +}K{sup {minus}} decay), jets, and two-boson correlations. The measurements are made down to small cross sections to allow the study of high p{sub T} spectra, and J/{psi} and {Upsilon} production. The PHENIX collaboration consists of over 300 scientists, engineers, and graduate students from 43 institutions in 10 countries. This large international collaboration is supported by US resources and significant foreign resources.

  18. The Pixel Detector of the ATLAS experiment for Run 2 of the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Oide, H.

    2014-12-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run 1 of the LHC. Taking advantage of the long shutdown, the detector was extracted from the experiment and brought to surface in order to equip it with new service quarter panels, to repair modules, and to ease installation of the Insertable B-Layer (IBL). The IBL is the fourth layer of the Run 2 Pixel Detector, and it was installed at a radius of 3.3 cm in May 2014 between the existing Pixel Detector and the new smaller-radius beam pipe. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, a new read-out chip and two different silicon sensor technologies (planar and 3D) have been developed. Furthermore, the physics performance is expected to improve through the reduction of pixel size. As well, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system were adopted. An overview of the IBL project as well as the experience in its construction is presented, focusing on adopted technologies, module and staves production, qualification of assembly procedure, integration of staves around the beam pipe, and commissioning of the detector.

  19. Fourth workshop on experiments and detectors for a relativistic heavy ion collider

    SciTech Connect

    Fatyga, M.; Moskowitz, B.

    1990-01-01

    This report contains papers on the following topics: physics at RHIC; flavor flow from quark-gluon plasma; space-time quark-gluon cascade; jets in relativistic heavy ion collisions; parton distributions in hard nuclear collisions; experimental working groups, two-arm electron/photon spectrometer collaboration; total and elastic pp cross sections; a 4{pi} tracking TPC magnetic spectrometer; hadron spectroscopy; efficiency and background simulations for J/{psi} detection in the RHIC dimuon experiment; the collision regions beam crossing geometries; Monte Carlo simulations of interactions and detectors; proton-nucleus interactions; the physics of strong electromagnetic fields in collisions of relativistic heavy ions; a real time expert system for experimental high energy/nuclear physics; the development of silicon multiplicity detectors; a pad readout detector for CRID/tracking; RHIC TPC R D progress and goals; development of analog memories for RHIC detector front-end electronic systems; calorimeter/absorber optimization for a RHIC dimuon experiment; construction of a highly segmented high resolution TOF system; progress report on a fast, particle-identifying trigger based on ring-imaging and highly integrated electronics for a TPC detector.

  20. Characterising dark matter searches at colliders and direct detection experiments: Vector mediators

    SciTech Connect

    Buchmueller, Oliver; Dolan, Matthew J.; Malik, Sarah A.; McCabe, Christopher

    2015-01-09

    We introduce a Minimal Simplified Dark Matter (MSDM) framework to quantitatively characterise dark matter (DM) searches at the LHC. We study two MSDM models where the DM is a Dirac fermion which interacts with a vector and axial-vector mediator. The models are characterised by four parameters: mDM, Mmed , gDM and gq, the DM and mediator masses, and the mediator couplings to DM and quarks respectively. The MSDM models accurately capture the full event kinematics, and the dependence on all masses and couplings can be systematically studied. The interpretation of mono-jet searches in this framework can be used to establish an equal-footing comparison with direct detection experiments. For theories with a vector mediator, LHC mono-jet searches possess better sensitivity than direct detection searches for light DM masses (≲5 GeV). For axial-vector mediators, LHC and direct detection searches generally probe orthogonal directions in the parameter space. We explore the projected limits of these searches from the ultimate reach of the LHC and multi-ton xenon direct detection experiments, and find that the complementarity of the searches remains. In conclusion, we provide a comparison of limits in the MSDM and effective field theory (EFT) frameworks to highlight the deficiencies of the EFT framework, particularly when exploring the complementarity of mono-jet and direct detection searches.

  1. Results from colliding magnetized plasma jet experiments executed at the Trident laser facility

    NASA Astrophysics Data System (ADS)

    Manuel, M. J.-E.; Rasmus, A. M.; Kurnaz, C. C.; Klein, S. R.; Davis, J. S.; Drake, R. P.; Montgomery, D. S.; Hsu, S. C.; Adams, C. S.; Pollock, B. B.

    2015-11-01

    The interaction of high-velocity plasma flows in a background magnetic field has applications in pulsed-power and fusion schemes, as well as astrophysical environments, such as accretion systems and stellar mass ejections into the magnetosphere. Experiments recently executed at the Trident Laser Facility at the Los Alamos National Laboratory investigated the effects of an expanding aluminum plasma flow into a uniform 4.5-Tesla magnetic field created using a solenoid designed and manufactured at the University of Michigan. Opposing-target experiments demonstrate interesting collisional behavior between the two magnetized flows. Preliminary interferometry and Faraday rotation measurements will be presented and discussed. This work is funded by the U.S Department of Energy, through the NNSA-DS and SC-OFES Joint Program in High-Energy-Density Laboratory Plasmas, grant number DE-NA0001840. Support for this work was provided by NASA through Einstein Postdoctoral Fellowship grant number PF3-140111 awarded by the Chandra X-ray Center, which is operated by the Astrophysical Observatory for NASA under contract NAS8-03060.

  2. Characterising dark matter searches at colliders and direct detection experiments: Vector mediators

    DOE PAGESBeta

    Buchmueller, Oliver; Dolan, Matthew J.; Malik, Sarah A.; McCabe, Christopher

    2015-01-09

    We introduce a Minimal Simplified Dark Matter (MSDM) framework to quantitatively characterise dark matter (DM) searches at the LHC. We study two MSDM models where the DM is a Dirac fermion which interacts with a vector and axial-vector mediator. The models are characterised by four parameters: mDM, Mmed , gDM and gq, the DM and mediator masses, and the mediator couplings to DM and quarks respectively. The MSDM models accurately capture the full event kinematics, and the dependence on all masses and couplings can be systematically studied. The interpretation of mono-jet searches in this framework can be used to establishmore » an equal-footing comparison with direct detection experiments. For theories with a vector mediator, LHC mono-jet searches possess better sensitivity than direct detection searches for light DM masses (≲5 GeV). For axial-vector mediators, LHC and direct detection searches generally probe orthogonal directions in the parameter space. We explore the projected limits of these searches from the ultimate reach of the LHC and multi-ton xenon direct detection experiments, and find that the complementarity of the searches remains. In conclusion, we provide a comparison of limits in the MSDM and effective field theory (EFT) frameworks to highlight the deficiencies of the EFT framework, particularly when exploring the complementarity of mono-jet and direct detection searches.« less

  3. Improvement of Digital Filter for the FNAL Booster Transverse Dampers

    SciTech Connect

    Zolkin, Timofey; Eddy, N.; Lebedev, V.

    2013-09-26

    Fermilab Booster has two transverse dampers which independently suppress beam instabilities in the horizontal and vertical planes. A suppression of the common mode signal is achieved by digital notch filter which is based on subtracting beam positions for two consecutive turns. Such system operates well if the orbit position changes sufficiently slow. Unfortunately it is not the case for FNAL Booster where the entire accelerating cycle consists of about 20000 turns, and successful transition crossing requires the orbit drifts up to about 10 μm/turn, resulting in excessive power, power amplifier saturation and loss of stability. To suppress this effect we suggest an improvement of the digital filter which can take into account fast orbit changes by using bunch positions of a few previous turns. To take into account the orbit change up toN-th order polynomial in time the system requires (N + 3) turns of “prehistory”. In the case of sufficiently small gain the damping rate and the optimal digital filter coefficients are obtained analytically. Numerical simulations verify analytical theory for the small gain and predict a system performance with gain increase.

  4. Galactic scale gas flows in colliding galaxies: 3-dimensional, N-body/hydrodynamics experiments

    NASA Technical Reports Server (NTRS)

    Lamb, Susan A.; Gerber, Richard A.; Balsara, Dinshaw S.

    1994-01-01

    We present some results from three dimensional computer simulations of collisions between models of equal mass galaxies, one of which is a rotating, disk galaxy containing both gas and stars and the other is an elliptical containing stars only. We use fully self consistent models in which the halo mass is 2.5 times that of the disk. In the experiments we have varied the impact parameter between zero (head on) and 0.9R (where R is the radius of the disk), for impacts perpendicular to the disk plane. The calculations were performed on a Cray 2 computer using a combined N-body/smooth particle hydrodynamics (SPH) program. The results show the development of complicated flows and shock structures in the direction perpendicular to the plane of the disk and the propagation outwards of a density wave in both the stars and the gas. The collisional nature of the gas results in a sharper ring than obtained for the star particles, and the development of high volume densities and shocks.

  5. Physics at hadron colliders: Experimental view

    SciTech Connect

    Siegrist, J.L.

    1987-08-01

    The physics of the hadron-hadron collider experiment is considered from an experimental point of view. The problems encountered in determination of how well the standard model describes collider results are discussed. 53 refs., 58 figs.

  6. Search for the Production of Gluinos and Squarks with the CDF II Experiment at the Tevatron Collider

    SciTech Connect

    De Lorenzo, Gianluca

    2010-05-19

    sbottom decays exclusively as $\\tilde{b}$1 → b$\\tilde{x}$10. The expected signal for direct sbottom pair production is characterized by the presence of two jets of hadrons from the hadronization of the bottom quarks and E=T from the two LSPs in the final state. The events are selected with large ET and two energetic jets in the final state, and at least one jet is required to be associated with a b quark. The measurements are in good agreement with SM predictions for backgrounds. The results are translated into 95% CL exclusion limits on production cross sections and sbottom and neutralino masses in the given MSSM scenario. Cross sections down to 0.1 pb are excluded for the sbottom mass range considered. Sbottom masses up to 230 GeV/c2 are excluded at 95% CL for neutralino masses below 70 GeV/c2. This analysis increases the previous CDF limit by more than 40 GeV/c2. The sensitivity of both the inclusive and the exclusive search is dominated by systematic effects and the results of the two analyses can be considered as conclusive for CDF Run II. With the new energy frontier of the newly commissioned Large Hadron Collider in Geneva, the experience from Tevatron will be of crucial importance in the developing of effective strategies to search for SUSY in the next era of particle physics experiments.

  7. Muon Collider

    SciTech Connect

    Palmer, R.

    2009-10-19

    Parameters are given of muon colliders with center of mass energies of 1.5 and 3 TeV. Pion production is from protons on a mercury target. Capture, decay, and phase rotation yields bunch trains of both muon signs. Six dimensional cooling reduces the emittances until the trains are merged into single bunches, one of each sign. Further cooling in 6 dimensions is then applied, followed by final transverse cooling in 50 T solenoids. After acceleration the muons enter the collider ring. Ongoing R&D is discussed.

  8. The Effect of Wedge Angle on the Evolution of a Stagnation Layer in a Colliding Plasma Experiment

    NASA Astrophysics Data System (ADS)

    Fallon, C.; Hayden, P.; Walsh, N.; Kennedy, E. T.; Costello, J. T.

    2014-11-01

    Colliding plasmas are steadily gaining significance in hohlraum studies, pulsed laser deposition and laser-induced breakdown spectroscopy for a number of reasons, not least the levels of control they o.er over the properties of the slab of plasma that accumulates at the collision front, i.e. the stagnation layer. We present here some results of a time and space resolved optical-spectroscopic study of colliding plasmas formed at the front surfaces of flat and inclined Cu slab targets as a function of the wedge angle between them for angles ranging from 100° to 180° (i.e., laterally colliding plasmas). Presented here are the kinetics of atomic/ionic spatial distributions throughout the stagnation layers, both of which have been found to vary significantly with wedge angle.

  9. HIGH ENERGY PHYSICS POTENTIAL AT MUON COLLIDERS

    SciTech Connect

    PARSA,Z.

    2000-04-07

    In this paper, high energy physics possibilities and future colliders are discussed. The {mu}{sup +} {mu}{sup {minus}} collider and experiments with high intensity muon beams as the stepping phase towards building Higher Energy Muon Colliders (HEMC) are briefly reviewed and encouraged.

  10. Colliding pulse injection experiments in non-collinear geometry for controlled laser plasma wakefield acceleration of electrons

    NASA Astrophysics Data System (ADS)

    Toth, Csaba; Nakamura, K.; Geddes, C.; Michel, P.; Schroeder, C.; Esarey, E.; Leemans, W.

    2006-10-01

    A method for controlled injection of electrons into a plasma wakefield relying on colliding laser pulses [1] has been proposed a decade ago to produce high quality relativistic electron beams with energy spread below 1% and normalized emittances < 1 micron from a laser wakefield accelerator (LWFA). The original idea uses three pulses in which one pulse excites the plasma wake and a trailing laser pulse collides with a counterpropagating one to form a beat pattern that boosts background electrons to catch the plasma wave. Another, two-beam off-axis injection method [2] with crossing angles varying from 180 to 90 degrees avoids having optical elements on the path of the electron beam and has been studied at the LOASIS facility of LBNL as a viable method for laser triggered injection. It allows low dark current operation with controllable final beam energy and low energy spread. Here, we report on progress of electron optical injection via the two-beam non-collinear colliding pulse scheme using multi-terawatt Ti:Sapphire laser beams (45 fs, 100s of mJ) focused onto a Hydrogen gas plume. Experimental results indicate that electron beam properties are affected by the second beam. *This work is supported by DoE under contract DE-AC02-05CH11231. [1] E. Esarey, et al, Phys. Rev. Lett 79, 2682 (1997) [2] G. Fubiani, Phys. Rev. E 70, 016402 (2004)

  11. Deducing the nature of dark matter from direct and indirect detection experiments in the absence of collider signatures of new physics

    SciTech Connect

    Beltran, Maria; Hooper, Dan; Kolb, Edward W.; Krusberg, Zosia A. C.

    2009-08-15

    Despite compelling arguments that significant discoveries of physics beyond the standard model are likely to be made at the Large Hadron Collider, it remains possible that this machine will make no such discoveries, or will make no discoveries directly relevant to the dark matter problem. In this article, we study the ability of astrophysical experiments to deduce the nature of dark matter in such a scenario. In most dark matter studies, the relic abundance and detection prospects are evaluated within the context of some specific particle physics model or models (e.g., supersymmetry). Here, assuming a single weakly interacting massive particle constitutes the Universe's dark matter, we attempt to develop a model-independent approach toward the phenomenology of such particles in the absence of any discoveries at the Large Hadron Collider. In particular, we consider generic fermionic or scalar dark matter particles with a variety of interaction forms, and calculate the corresponding constraints from and sensitivity of direct and indirect detection experiments. The results may provide some guidance in disentangling information from future direct and indirect detection experiments.

  12. Kaonic 3He and 4He measurements in the SIDDHARTA experiment at the DAΦNE collider

    NASA Astrophysics Data System (ADS)

    Tatsuno, H.; Bazzi, M.; Beer, G.; Bombelli, L.; Bragadireanu, A. M.; Cargnelli, M.; Curceanu (Petrascu), C.; d'Uffizi, A.; Fiorini, C.; Frizzi, T.; Ghio, F.; Guaraldo, C.; Hayano, R. S.; Iliescu, M.; Ishiwatari, T.; Iwasaki, M.; Kienle, P.; Levi Sandri, P.; Longoni, A.; Marton, J.; Okada, S.; Pietreanu, D.; Ponta, T.; Rizzo, A.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tudorache, A.; Tudorache, V.; Vazquez Doce, O.; Widmann, E.; Wünschek, B.; Zmeskal, J.

    2012-12-01

    The SIDDHARTA collaboration measured kaonic 3He and 4He 3d → 2p X-rays with gaseous targets at the DAΦNE e+e- collider. The 2p-state strong-interaction shifts and widths were precisely determined by using 144 high-resolution silicon drift detectors. The shift of K-4He is in good agreement with theoretical calculations and consistent with the recent experimental result of KEK-PS E570. The shift of K-3He is also determined for the first time. The newly determined widths are in agreement with optical model calculations.

  13. Unlocking the secrets of the kaon-nucleon/nuclei interactions at low-energies: The SIDDHARTA(-2) and the AMADEUS experiments at the DAΦNE collider

    NASA Astrophysics Data System (ADS)

    Curceanu, C.; Bazzi, M.; Beer, G.; Berucci, C.; Bombelli, L.; Bragadireanu, A. M.; Cargnelli, M.; Clozza, A.; d'Uffizi, A.; Fiorini, C.; Frizzi, T.; Ghio, F.; Guaraldo, C.; Hayano, R. S.; Iliescu, M.; Ishiwatari, T.; Iwasaki, M.; Kienle, P.; Levi Sandri, P.; Longoni, A.; Marton, J.; Okada, S.; Pietreanu, D.; Piscicchia, K.; Poli Lener, M.; Ponta, T.; Romero Vidal, A.; Sbardella, E.; Scordo, A.; Shi, H.; Sirghi, D. L.; Sirghi, F.; Tatsuno, H.; Tudorache, A.; Tudorache, V.; Vazquez Doce, O.; Widmann, E.; Wünschek, B.; Zmeskal, J.

    2013-09-01

    The DAΦNE electron-positron collider at the Laboratori Nazionali di Frascati of INFN has made available a unique quality low-energy negative kaons “beam”, which is being used to unlock the secrets of the kaon-nucleon/nuclei interactions at low energies by the SIDDHARTA(-2) and the AMADEUS experiments. SIDDHARTA has already performed unprecedented precision measurements of kaonic atoms, and is being presently upgraded, as SIDDHARTA-2, to approach new frontiers. The AMADEUS experiment already started a data taking with a dedicated carbon target, plans to perform in the coming years precision measurements on kaon-nuclei interactions at low-energies, in particular to study the possible formation of kaonic nuclei and the Λ(1405). The two experiments are briefly presented in this paper.

  14. Stable massive particles at colliders

    SciTech Connect

    Fairbairn, M.; Kraan, A.C.; Milstead, D.A.; Sjostrand, T.; Skands, P.; Sloan, T.; /Lancaster U.

    2006-11-01

    We review the theoretical motivations and experimental status of searches for stable massive particles (SMPs) which could be sufficiently long-lived as to be directly detected at collider experiments. The discovery of such particles would address a number of important questions in modern physics including the origin and composition of dark matter in the universe and the unification of the fundamental forces. This review describes the techniques used in SMP-searches at collider experiments and the limits so far obtained on the production of SMPs which possess various colour, electric and magnetic charge quantum numbers. We also describe theoretical scenarios which predict SMPs, the phenomenology needed to model their production at colliders and interactions with matter. In addition, the interplay between collider searches and open questions in cosmology such as dark matter composition are addressed.

  15. Neutrino physics at muon colliders

    SciTech Connect

    King, B.J.

    1998-03-01

    An overview is given of the neutrino physics potential of future muon storage rings that use muon collider technology to produce, accelerate and store large currents of muons. After a general characterization of the neutrino beam and its interactions, some crude quantitative estimates are given for the physics performance of a muon ring neutrino experiment (MURINE) consisting of a high rate, high performance neutrino detector at a 250 GeV muon collider storage ring.

  16. B physics at hadron colliders

    SciTech Connect

    Butler, J.N.; /Fermilab

    2005-09-01

    This paper discusses the physics opportunity and challenges for doing high precision B physics experiments at hadron colliders. It describes how these challenges have been addressed by the two currently operating experiments, CDF and D0, and how they are addressed by three experiments, ATLAS, CMS, and LHCb, at the LHC.

  17. Effects of momentum conservation and flow on angular correlations observed in experiments at the BNL Relativistic Heavy Ion Collider

    SciTech Connect

    Pratt, Scott; Schlichting, Soeren; Gavin, Sean

    2011-08-15

    Correlations of azimuthal angles observed at the Relativistic Heavy Ion Collider have gained great attention due to the prospect of identifying fluctuations of parity-odd regions in the field sector of QCD. Whereas the observable of interest related to parity fluctuations involves subtracting opposite-sign from same-sign correlations, the STAR collaboration reported the same-sign and opposite-sign correlations separately. It is shown here how momentum conservation combined with collective elliptic flow contributes significantly to this class of correlations, although not to the difference between the opposite- and same-sign observables. The effects are modeled with a crude simulation of a pion gas. Although the simulation reproduces the scale of the correlation, the centrality dependence is found to be sufficiently different in character to suggest additional considerations beyond those present in the pion gas simulation presented here.

  18. Material Procurement Report for the FNAL pp Forward Detector's Toroids and Cos8 Dipole Magnets

    SciTech Connect

    Cline, D.; Morse, R.; Orosz, I.; Thomas, L.C.

    1980-10-27

    We outline the possibilities of starting construction of the {bar p}p forward detector toroids and cos{theta} dipole magnets described in CDP Note 64 as soon as possible using material that already exists on the FNAL site. Personal inspection of the steel supplies indicates that as much as 2000 tons of steel or over 50% of all the steel needed for the toroids is now available at the FNAL boneyard. Copper inventories indicate that there is enough copper on the FNAL site to construct both the toroid magnets and the cos{theta} dipole magnets. A construction schedule of one toroid in FY81, two toroids in FY82, and the final toroid in FY83 is shown to be feasible. Floor space and loading requirements for the IR Hall housing the forward detector are examined and finally, budgets for the initial FY8l phase and the completed project are given. The FY81 costs are $393K and to-completion costs are $1506K.

  19. Search for electroweak single top-quark production with the CDF II experiment

    SciTech Connect

    Richter, Svenja

    2007-11-02

    Understanding the world -- This aim drives humankind since the beginning of conscious thinking. Especially the nature of matter has been of major interest. Nowadays, we have a complex image of the constitution of matter. Atoms consist of electrons and nucleons. But even nucleons are not elementary. Their basic constituents are called quarks. Physicists developed a model describing the elementary components of matter as well as the forces between them: the standard model of elementary particle physics. The substructure of matter is only visible in scattering experiments. In high energy physics, these experiments are done at particle accelerators. The world's highest energetic collider, the Tevatron, is hosted by the Fermi National Accelerator Laboratory (FNAL), also called Fermilab, in the vicinity of Chicago. The proton-antiproton collisions with a center-of-mass energy of {radical}s = 1.96 TeV are recorded by two multipurpose detectors, namely D0 and CDF II.

  20. Update to Proposal for an Experiment to Measure Mixing, CP Violation and rare Decays in Charm and Beauty Particle Decays at the Fermilac Collider - BTeV

    SciTech Connect

    Butler, Joel; Stone, Sheldon

    2002-03-01

    We have been requested to submit an update of the BTe V plan to the Fermilab Physics Advisory Committee, where to save money the detector has only one arm and there is no new interaction region magnet construction planned. These are to come from a currently running collider experiment at the appropriate time. The "Physics Case" section is complete and updated with the section on the "New Physics" capabilites of BTe V greatly expanded. We show that precise measurments of rare flavor-changing neutral current processes and CP violation are and will be complementary to the Tevatron and LHC to unraveling the electroweak breaking puzzle. We include a revised summary of the physics sensitivities for the one-arm detector, which are not simply taking our proposal numbers and dividing by two, because of additional improvements. One important change resulted from an improved understanding of just how important the RJCH detector is to muon and electron identification, that we can indeed separate electrons from pions and muons from pions, especially at relatively large angles beyond the physical appature of the EM calorimeter or the Muon Detector. This is documented in the "Physics Sensitivities" section. The section on the detector includes the motivation for doing band c physics at a hadron collider, and shows the changes in the detector since the proposal based on our ongoing R&D program. We do not here include a detailed description of the entire detector. That is available in the May, 2000 proposal.2 We include a summary of our R&D activities for the entire experiment. Finally, we also include a fully updated cost estimate for the one-arm system.

  1. 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

  2. Tau physics at p[bar p] colliders

    SciTech Connect

    Konigsberg, J. . High Energy Physics Lab.)

    1993-01-01

    Tau detection techniques in hadron colliders are discussed together with the measurements and searches performed so far. We also underline the importance tau physics has in present and future collider experiments.

  3. Tau physics at p{bar p} colliders

    SciTech Connect

    Konigsberg, J.

    1993-01-01

    Tau detection techniques in hadron colliders are discussed together with the measurements and searches performed so far. We also underline the importance tau physics has in present and future collider experiments.

  4. Experimental Study of W Z Intermediate Bosons Associated Production with the CDF Experiment at the Tevatron Collider

    SciTech Connect

    Pozzobon, Nicola; /Pisa U.

    2007-09-01

    Studying WZ associated production at the Fermilab Tevatron Collider is of great importance for two main reasons. On the one hand, this process would be sensitive to anomalies in the triple gauge couplings such that any deviation from the value predicted by the Standard Model would be indicative of new physics. In addition, by choosing to focus on the final state where the Z boson decays to b{bar b} pairs, the event topology would be the same as expected for associated production of a W and a Standard Model light Higgs boson (m{sub H} {approx}< 135 GeV) which decays into b{bar b} pairs most of times. The process WH {yields} W b{bar b} has an expected {sigma} {center_dot} B about five times lower than WZ {yields} Wb{bar b} for m{sub H} {approx_equal} 120 GeV. Therefore, observing this process would be a benchmark for an even more difficult search aiming at discovering the light Higgs in the WH {yields} Wb{bar b} process. After so many years of Tevatron operation only a weak WZ signal was recently observed in the full leptonic decay channel, which suffers from much less competition from background. Searching for the Z in the b{bar b} decay channel in this process is clearly a very challenging endeavour. In the work described in this thesis, WZ production is searched for in a final state where the W decays leptonically to an electron-neutrino pair or a muon-neutrino pair, with associated production of a jet pair consistent with Z decays. A set of candidate events is obtained by applying appropriate cuts to the parameters of events collected by wide acceptance leptonic triggers. To improve the signal fraction of the selected events, an algorithm was used to tag b-flavored jets by means of their content of long lived b-hadrons and corrections were developed to the jet algorithm to improve the b-jet energy resolution for a better reconstruction of the Z mass. In order to sense the presence of a signal one needs to estimate the amount of background. The relative content of

  5. Overview and Performance of the Fnal Ktev Daq System

    NASA Astrophysics Data System (ADS)

    Nakaya, T.; O'Dell, V.; Hazumi, M.; Yamanaka, T.

    KTeV is a new fixed target experiment at Permilab designed to study CP violation in the neutral kaon system. The KTeV Data Acquisition System (DAQ) is one of the highest performance DAQ's in the field of high energy physics. The sustained data throughput of the KTeV DAQ reaches 160 Mbytes/sec, and the available online level 3 processing power is 3600 Mips. In order to handle such high data throughput, the KTeV DAQ is designed around a memory matrix core where the data flow is divided and parallelized. In this paper, we present the architecture and test results of the KTeV DAQ system.

  6. Observation of transverse instabilities in the FNAL 200 MeV Linac

    SciTech Connect

    McCrory, E.; Lee, G.; Webber, R.C.

    1988-10-01

    Using newly installed Beam Position Monitors in the downstream half of the FNAL Linac, we have observed significant transverse beam instabilities within the 30 ..mu..s beam pulse. We can affect the instability so that the peak-to-peak amplitude is as small as 0.5 mm or as large as 8 mm. The effect is largely due to a beam-plasma instability in the ten-meter 750-keV transport line. Other causes are being investigated. Using these instabilities as an analysis tool, the betatron amplitude of the beam has been reduced. 7 refs., 4 figs.

  7. Status of LCLS - II QA Systems Collaboration for Cyromodule Construction at TJNAF and FNAL

    SciTech Connect

    McEwen, E. A.; Leung, J.; Bookwalter, V.; Blowers, J.; Szal, J.

    2015-09-25

    At the Thomas Jefferson National Accelerator Facility (Jefferson Lab), we are supporting the LCLS-II Project at SLAC. The plan is to build thirty-five 1.3 GHz continuous wave cryomodules, production to be split between JLab and FNAL (Fermilab). This has required a close collaboration between the partner labs, including enhancing our existing quality systems to include this collaboration. This overview describes the current status of the Quality System development as of August 2015, when the partner labs start the assembly of the prototype cryomodules.

  8. Simulation of Multipacting in SC Low Beta Cavities at FNAL

    SciTech Connect

    Romanov, Gennady; Berrutti, Paolo; Khabiboulline, Timergali

    2015-06-01

    Proton Improvement Plan-II at Fermilab is a plan for improvements to the accelerator complex aimed at providing a beam power capability of at least 1 MW on target at the initiation of LBNE (Long Base Neutrino Experiment) operations. The central element of the PIP-II is a new 800 MeV superconducting linac, injecting into the existing Booster. Multipacting affects superconducting RF cavities in the entire range from high energy elliptical cavities to coaxial resonators for low-beta applications. This work is focused on multipacting study in the low-beta 325 MHz spoke cavities; namely SSR1 and SSR2, which are especially susceptible to the phenomena. The extensive simulations of multipacting in the cavities with updated material properties and comparison of the results with experimental data helped us to improve overall reliability and accuracy of these simulations. Our practical approach to the simulations is described in details. For SSR2, which has a high multipacting barrier right at the operating power level, some changes of the cavity shape to mitigate this harmful phenomenon are proposed.

  9. CERN's Large Hadron Collider project

    NASA Astrophysics Data System (ADS)

    Fearnley, Tom A.

    1997-03-01

    The paper gives a brief overview of CERN's Large Hadron Collider (LHC) project. After an outline of the physics motivation, we describe the LHC machine, interaction rates, experimental challenges, and some important physics channels to be studied. Finally we discuss the four experiments planned at the LHC: ATLAS, CMS, ALICE and LHC-B.

  10. The Insertable B-Layer of the ATLAS experiment for the Run-2 at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Guescini, Francesco

    2015-10-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long shutdown, the detector was extracted from the experiment and brought to surface, to equip it with new Service Quarter Panels, to repair modules and to ease installation of the Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors and has been installed in May 2014 between the existing Pixel Detector and a new smaller radius beam pipe at a radial distance of 3.3 cm from the beam axis. The realization of the IBL required the development of several new technologies and solutions in order to overcome the challenges introduced by the extreme environment and working conditions, such as the high radiation levels, the high pixel occupancy and the need of an exceptionally low material budget. Two silicon sensor technologies have been adopted for the IBL modules: planar and 3D. Both of these are connected via bump-bonding to the new FE-I4 front-end read-out chip. Furthermore, the physics performance will be improved through the reduction of pixel size while, targeting for a low material budget, a new mechanical support using lightweight staves and a CO2 based cooling system have been adopted. An overview of the IBL project as well as the experience in its construction is presented, focusing on adopted technologies, modules and staves production, qualification of assembly procedure, integration of staves around the beam pipe and commissioning of the detector.

  11. When hope and fear collide: Expectations and experiences of first-year doctoral students in the natural sciences

    NASA Astrophysics Data System (ADS)

    Robinson, C. Sean

    Although there is a significant body of research on the process of undergraduate education and retention, much less research exists as it relates to the doctoral experience, which is intended to be transformational in nature. At each stage of the process students are presented with a unique set of challenges and experiences that must be negotiated and mastered. However, we know very little about entering students' expectations, beliefs, goals, and identities, and how these may or may not change over time within a doctoral program. Utilizing a framework built upon socialization theory and cognitive-ecological theory, this dissertation examines the expectations that incoming doctoral students have about their programs as well as the actual experiences that these students have during their first year. Interviews were conducted with twelve students from the departments of Botany, Chemistry, and Physics prior to matriculation into their respective doctoral programs. These initial interviews provided information about students' expectations. Interviews were then conducted approximately every six to eight weeks to assess students' perceptions about their actual experiences throughout their first year. The findings of this study showed that new doctoral students tend to have uninformed and naive expectations about their programs. In addition, many of the specific policies or procedures necessary for navigation through a doctoral program were unknown to the students. While few differences existed in terms of students' expectations based on gender or discipline, there were significant differences in how international students described their expectations compared to American students. The two primary differences between American and international students revolved around the role of faculty members and the language barrier. It is clear that the first year of doctoral study is indeed a year of transition. The nature and clarity of the expectations associated with the role of

  12. Photon collider Higgs factories

    NASA Astrophysics Data System (ADS)

    Telnov, V. I.

    2014-09-01

    The discovery of the Higgs boson (and still nothing else) have triggered appearance of many proposals of Higgs factories for precision measurement of the Higgs properties. Among them there are several projects of photon colliders (PC) without e+e- in addition to PLC based on e+e- linear colliders ILC and CLIC. In this paper, following a brief discussion of Higgs factories physics program I give an overview of photon colliders based on linear colliders ILC and CLIC, and of the recently proposed photon-collider Higgs factories with no e+e- collision option based on recirculation linacs in ring tunnels.

  13. THERMAL SHOCK INDUCED BY A 24 GEV PROTON BEAM IN THE TEST WINDOWS OF THE MUON COLLIDER EXPERIMENT E951 - TEST RESULTS AND THEORETICAL PREDICTIONS.

    SciTech Connect

    SIMOS,N.; KIRK,H.; FINFROCK,C.; PRIGL,R.; BROWN,K.; KAHN,S.; LUDEWIG,H.; MCDONALDK.; CATES,M.; TSAI,J.; BESHEARS,D.; RIEMER,B.

    2001-11-11

    The need for intense muon beams for muon colliders and neutrino factories has lead to a concept of a high performance target station in which a 1-4 MW proton beam of 6-24 GeV impinges on a target inside a high field solenoid channel. While novel technical issues exist regarding the survivability of the target itself, the need to pass the tightly focused proton beam through beam windows poses additional concerns. In this paper, issues associated with the interaction of a proton beam with window structures designed for the muon targetry experiment E951 at BNL are explored. Specifically, a 24 GeV proton beam up to 16 x 10{sup 12} per pulse and a pulse length of approximately 100 ns is expected to be tightly focused (to 0.5 mm rms one sigma radius) on an experimental target. Such beam will induce very high thermal, quasi-static and shock stresses in the window structure that exceed the strength of most common materials. In this effort, a detailed assessment of the thermal/shock response of beam windows is attempted with a goal of identifying the best window material candidate. Further, experimental strain results and comparison with the predicted values are presented and discussed.

  14. PHENIX CDR update: An experiment to be performed at the Brookhaven National Laboratory relativistic heavy ion collider. Revision

    SciTech Connect

    Not Available

    1994-11-01

    The PHENIX Conceptual Design Report Update (CDR Update) is intended for use together with the Conceptual Design Report (CDR). The CDR Update is a companion document to the CDR, and it describes the collaboration`s progress since the CDR was submitted in January 1993. Therefore, this document concentrates on changes, refinements, and decisions that have been made over the past year. These documents together define the baseline PHENIX detector that the collaboration intends to build for operation at RHIC startup. In this chapter the current status of the detector and its motivation are briefly described. In Chapters 2 and 3 the detector and the physics performance are more fully developed. In Chapters 4 through 13 the details of the present design status, the technology choices, and the construction costs and schedules are presented. The physics goals of PHENIX collaboration have remained exactly as they were described in the CDR. Primary among these is the detection of a new phase of matter, the quark-gluon plasma (QGP), and the measurement of its properties. The PHENIX experiment will measure many of the best potential QGP signatures to see if any or all of these physics variables show anomalies simultaneously due to the formation of the QGP.

  15. Muon Collider Task Force Report

    SciTech Connect

    Ankenbrandt, C.; Alexahin, Y.; Balbekov, V.; Barzi, E.; Bhat, C.; Broemmelsiek, D.; Bross, A.; Burov, A.; Drozhdin, A.; Finley, D.; Geer, S.; /Fermilab /Argonne /Brookhaven /Jefferson Lab /LBL, Berkeley /MUONS Inc., Batavia /UCLA /UC, Riverside /Mississippi U.

    2007-12-01

    Muon Colliders offer a possible long term path to lepton-lepton collisions at center-of-mass energies {radical}s {ge} 1 TeV. In October 2006 the Muon Collider Task Force (MCTF) proposed a program of advanced accelerator R&D aimed at developing the Muon Collider concept. The proposed R&D program was motivated by progress on Muon Collider design in general, and in particular, by new ideas that have emerged on muon cooling channel design. The scope of the proposed MCTF R&D program includes muon collider design studies, helical cooling channel design and simulation, high temperature superconducting solenoid studies, an experimental program using beams to test cooling channel RF cavities and a 6D cooling demonstration channel. The first year of MCTF activities are summarized in this report together with a brief description of the anticipated FY08 R&D activities. In its first year the MCTF has made progress on (1) Muon Collider ring studies, (2) 6D cooling channel design and simulation studies with an emphasis on the HCC scheme, (3) beam preparations for the first HPRF cavity beam test, (4) preparations for an HCC four-coil test, (5) further development of the MANX experiment ideas and studies of the muon beam possibilities at Fermilab, (6) studies of how to integrate RF into an HCC in preparation for a component development program, and (7) HTS conductor and magnet studies to prepare for an evaluation of the prospects for of an HTS high-field solenoid build for a muon cooling channel.

  16. Collider Signal I :. Resonance

    NASA Astrophysics Data System (ADS)

    Tait, Tim M. P.

    2010-08-01

    These TASI lectures were part of the summer school in 2008 and cover the collider signal associated with resonances in models of physics beyond the Standard Model. I begin with a review of the Z boson, one of the best-studied resonances in particle physics, and review how the Breit-Wigner form of the propagator emerges in perturbation theory and discuss the narrow width approximation. I review how the LEP and SLAC experiments could use the kinematics of Z events to learn about fermion couplings to the Z. I then make a brief survey of models of physics beyond the Standard Model which predict resonances, and discuss some of the LHC observables which we can use to discover and identify the nature of the BSM physics. I finish up with a discussion of the linear moose that one can use for an effective theory description of a massive color octet vector particle.

  17. Physics goals of the next linear collider

    SciTech Connect

    Kuhlman, S.; Marciano, W.J.; Gunion, J. F.; NLC ZDR Design Group; NLC Physics Working Group

    1996-05-01

    We present the prospects for the next generation of high-energy physics experiments with electron-positron colliding beams. This report summarizes the current status of the design and technological basis of a linear collider of center of mass energy 500 GeV-1.5 TeV, and the opportunities for high-energy physics experiments that this machine is expected to open. 132 refs., 54 figs., 14 tabs.

  18. Design of 325 MHz single and triple spoke resonators at FNAL

    SciTech Connect

    Lanfranco, G.; Apollinari, G.; Gonin, I.; Khabiboulline, T.; McConologue, F.; Romanov, G.; Wagner, R.; /Fermilab

    2006-08-01

    The proposed 8-GeV driver at FNAL is based on approximately 400 independently phased SC resonators. In this paper the design of 325 MHz Spoke Resonators, two single spoke resonators ({beta}=0.22 and {beta}=0.4) and a triple spoke resonator ({beta}=0.62), for the High Intensity Neutrino Source (HINS) front end is presented. We describe the optimization of the spoke resonators geometry, the goal being to minimize the E{sub peak}/E{sub acc} and B{sub peak}/E{sub acc} ratios. We report on the coupled ANSYS-MWS analysis on the resonators mechanical properties and power coupler RF design. The current status of mechanical design, slow tuning mechanism and cryostat are also presented.

  19. Electron-Cloud Build-up in the FNAL Main Injector

    SciTech Connect

    Furman, M.A.

    2007-06-04

    We present a summary on ongoing simulation results for the electron-cloud buildup in the context of the proposed FNAL Main Injector (MI) intensity upgrade [1] in a fieldfree region at the location of the RFA electron detector [2]. By combining our simulated results for the electron flux at the vacuum chamber wall with the corresponding measurements obtained with the RFA we infer that the peak secondary electron yield (SEY) {delta}{sub max} is {approx}> 1.4, and the average electron density is n{sub e} {approx}> 10{sup 10} m{sup -3} at transition energy for the specific fill pattern and beam intensities defined below. The sensitivity of our results to several variables remains to be explored in order to reach more definitive results. Effects from the electron cloud on the beam are being investigated separately [3].

  20. Proposal for Drell-Yan Measurements of Nucleon and Nuclear Structure with the FNAL Main Injector

    SciTech Connect

    Isenhower, L.D.; Sadler, M.E.; Arrinton, J.; Geesamn, D.F.; Holt, R.J.; Jackson, H.E.; Reimer, P.E.; Potterveld, D.H.; Brown, C.N.; Garvey, G.T.; Leitch, M.J.; /Los Alamos /Rutgers U. /Texas A-M /Valparaiso U.

    2001-04-01

    We propose measuring the fractional momentum (x) dependence of the ratio of the anti-down to anti-up quark distributions in the proton, {bar d}(x)/{bar u}(x), using proton induced Drell-Yan reactions at 120 GeV. Recent measurements by FNAL E866 unexpectedly show considerable x dependence in this ratio for x > 0.2. A lower energy primary proton beam from the Main Injector makes it possible to extend the E866 measurements to larger x with much higher precision. The apparatus will also be used with nuclear targets to measure parton energy loss and modifications to anti-quark distributions in nuclear targets at large x (x > 0.2).

  1. Reduction of beam current noise in the FNAL magnetron ion source

    SciTech Connect

    Bollinger, D. S. Karns, P. R. Tan, C. Y.

    2015-04-08

    The new FNAL Injector Line with a circular dimple magnetron ion source has been operational since December of 2012. Since the new injector came on line there have been variations in the H- beam current flattop observed near the downstream end of the Linac. Several different cathode geometries including a hollow cathode suggested by Dudnikov [1] were tried. Previous studies also showed that different mixtures of hydrogen and nitrogen had an effect on beam current noise [2]. We expanded on those studies by trying mixtures ranging from (0.25% nitrogen, 99.75% hydrogen) to (3% nitrogen, 97% hydrogen). The results of these studies in our test stand will be presented in this paper.

  2. State of hadron collider physics

    SciTech Connect

    Grannis, P.D. |

    1993-12-01

    The 9th Topical Workshop on Proton-Antiproton Collider Physics in Tsukuba Japan demonstrated clearly the enormous breadth of physics accessible in hadron cowders. Although no significant chinks were reported in the armor of the Standard Model, new results presented in this meeting have expanded our knowledge of the electroweak and strong interactions and have extended the searches for non-standard phenomena significantly. Much of the new data reported came from the CDF and D0 experiments at the Fermilab cowder. Superb operation of the Tevatron during the 1992-1993 Run and significant advances on the detector fronts -- in particular, the emergence of the new D0 detector as a productive physics instrument in its first outing and the addition of the CDF silicon vertex detector -- enabled much of this advance. It is noteworthy however that physics from the CERN collider experiments UA1 and UA4 continued to make a large impact at this meeting. In addition, very interesting summary talks were given on new results from HERA, cosmic ray experiments, on super-hadron collider physics, and on e{sup +}e{sup {minus}} experiments at LEP and TRISTAN. These summaries are reported in elsewhere in this volume.

  3. SLAC Linear Collider

    SciTech Connect

    Richter, B.

    1985-12-01

    A report is given on the goals and progress of the SLAC Linear Collider. The status of the machine and the detectors are discussed and an overview is given of the physics which can be done at this new facility. Some ideas on how (and why) large linear colliders of the future should be built are given.

  4. SLAC linear collider

    SciTech Connect

    Richter, B.; Bell, R.A.; Brown, K.L.

    1980-06-01

    The SLAC LINEAR COLLIDER is designed to achieve an energy of 100 GeV in the electron-positron center-of-mass system by accelerating intense bunches of particles in the SLAC linac and transporting the electron and positron bunches in a special magnet system to a point where they are focused to a radius of about 2 microns and made to collide head on. The rationale for this new type of colliding beam system is discussed, the project is described, some of the novel accelerator physics issues involved are discussed, and some of the critical technical components are described.

  5. Fast feedback for linear colliders

    SciTech Connect

    Hendrickson, L.; Adolphsen, C.; Allison, S.; Gromme, T.; Grossberg, P.; Himel, T.; Krauter, K.; MacKenzie, R.; Minty, M.; Sass, R.

    1995-05-01

    A fast feedback system provides beam stabilization for the SLC. As the SLC is in some sense a prototype for future linear colliders, this system may be a prototype for future feedbacks. The SLC provides a good base of experience for feedback requirements and capabilities as well as a testing ground for performance characteristics. The feedback system controls a wide variety of machine parameters throughout the SLC and associated experiments, including regulation of beam position, angle, energy, intensity and timing parameters. The design and applications of the system are described, in addition to results of recent performance studies.

  6. Photon Collider Physics with Real Photon Beams

    SciTech Connect

    Gronberg, J; Asztalos, S

    2005-11-03

    Photon-photon interactions have been an important probe into fundamental particle physics. Until recently, the only way to produce photon-photon collisions was parasitically in the collision of charged particles. Recent advances in short-pulse laser technology have made it possible to consider producing high intensity, tightly focused beams of real photons through Compton scattering. A linear e{sup +}e{sup -} collider could thus be transformed into a photon-photon collider with the addition of high power lasers. In this paper they show that it is possible to make a competitive photon-photon collider experiment using the currently mothballed Stanford Linear Collider. This would produce photon-photon collisions in the GeV energy range which would allow the discovery and study of exotic heavy mesons with spin states of zero and two.

  7. Linear collider: a preview

    SciTech Connect

    Wiedemann, H.

    1981-11-01

    Since no linear colliders have been built yet it is difficult to know at what energy the linear cost scaling of linear colliders drops below the quadratic scaling of storage rings. There is, however, no doubt that a linear collider facility for a center of mass energy above say 500 GeV is significantly cheaper than an equivalent storage ring. In order to make the linear collider principle feasible at very high energies a number of problems have to be solved. There are two kinds of problems: one which is related to the feasibility of the principle and the other kind of problems is associated with minimizing the cost of constructing and operating such a facility. This lecture series describes the problems and possible solutions. Since the real test of a principle requires the construction of a prototype I will in the last chapter describe the SLC project at the Stanford Linear Accelerator Center.

  8. Relativistic Heavy Ion Collider

    SciTech Connect

    Willen, E.H.

    1986-01-01

    The Relativistic Heavy Ion Collider (RHIC) is a proposed research facility at Brookhaven National Laboratory to study the collision of beams of heavy ions, up to gold in mass and at beam energies up to 100 GeV/nucleon. The physics to be explored by this collider is an overlap between the traditional disciplines of nuclear physics and high energy physics and is a continuation of the planned program of light and heavy ion physics at BNL. The machine is to be constructed in the now-empty tunnel built for the former CBA project. Various other facilities to support the collider are either in place or under construction at BNL. The collider itself, including the magnets, is in an advanced state of design, and a construction start is anticipated in the next several years.

  9. Photon collider at TESLA

    NASA Astrophysics Data System (ADS)

    Telnov, Valery

    2001-10-01

    High energy photon colliders ( γγ, γe) based on backward Compton scattering of laser light is a very natural addition to e +e - linear colliders. In this report, we consider this option for the TESLA project. Recent study has shown that the horizontal emittance in the TESLA damping ring can be further decreased by a factor of four. In this case, the γγ luminosity in the high energy part of spectrum can reach about (1/3) Le +e -. Typical cross-sections of interesting processes in γγ collisions are higher than those in e +e - collisions by about one order of magnitude, so the number of events in γγ collisions will be more than that in e +e - collisions. Photon colliders can, certainly, give additional information and they are the best for the study of many phenomena. The main question is now the technical feasibility. The key new element in photon colliders is a very powerful laser system. An external optical cavity is a promising approach for the TESLA project. A free electron laser is another option. However, a more straightforward solution is "an optical storage ring (optical trap)" with a diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based on the linear collider TESLA, its possible parameters and existing problems.

  10. Commissioning and Operation of the FNAL Front end Injection Line and Ion Sources.

    SciTech Connect

    Karns, Patrick R.

    2015-09-01

    This thesis documents the efforts made in commissioning and operating the RFQ Injection Line (RIL) as a replacement for the Cockcroft Walton front end. The Low Energy Beam Transport (LEBT) was assembled and tested with multiwire position and emittance monitor measurements. The Radio Frequency Quadrupole (RFQ) commissioning was completed with the same measurements as well as output beam energy measurements that showed it initially accelerated beam only to 700 keV, which was 50 keV lower than the design energy. Working with the manufacturer solutions were found and instituted to continue testing. The Medium Energy Beam Transport (MEBT) was then connected as the RIL was installed as the new front end of Linac. Testing gave way to operation when the new front end was used as the source of all High Energy Physics (HEP) beam for Fermi National Accelerator Laboratory (FNAL). The magnetron ion source that provides the H- beam for the front end required several changes and eventual upgrades to operate well; such as new source operating points for vacuum pressure and cesium admixture, and new materials for critical source components. Further research was conducted on the cathode geometry and nitrogen doping of the hydrogen gas as well as using solid state switches for the extractor system high voltage.

  11. Commissioning and operation of the FNAL front end injection line and ion sources

    NASA Astrophysics Data System (ADS)

    Karns, Patrick R.

    This thesis documents the efforts made in commissioning and operating the RFQ Injection Line (RIL) as a replacement for the Cockcroft Walton front end. The Low Energy Beam Transport (LEBT) was assembled and tested with multiwire position and emittance monitor measurements. The Radio Frequency Quadrupole (RFQ) commissioning was completed with the same measurements as well as output beam energy measurements that showed it initially accelerated beam only to 700 keV, which was 50 keV lower than the design energy. Working with the manufacturer solutions were found and instituted to continue testing. The Medium Energy Beam Transport (MEBT) was then connected as the RIL was installed as the new front end of Linac. Testing gave way to operation when the new front end was used as the source of all High Energy Physics (HEP) beam for Fermi National Accelerator Laboratory (FNAL). The magnetron ion source that provides the H- beam for the front end required several changes and eventual upgrades to operate well; such as new source operating points for vacuum pressure and cesium admixture, and new materials for critical source components. Further research was conducted on the cathode geometry and nitrogen doping of the hydrogen gas as well as using solid state switches for the extractor system high voltage.

  12. Physics at the linear collider

    NASA Astrophysics Data System (ADS)

    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.

    2015-08-01

    A comprehensive review of physics at an linear collider in the energy range of 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.

  13. Tevatron collider operations and plans

    SciTech Connect

    Peter H. Garbincius

    2004-06-17

    Fermilab's Tevatron is a proton-antiproton collider with center of mass energy of 1.96 TeV. The antiprotons are produced by 125 GeV protons from the Main Injector striking a stainless steel target. The 8 GeV antiprotons are collected and cooled in the Debuncher and Accumulator rings of the Antiproton Source and, just recently, in the Recycler ring before acceleration by the Main Injector and the Tevatron. In addition to energy, a vital parameter for generating physics data is the Luminosity delivered to the experiments given by a formula that is listed in detail in the paper.

  14. Dynamic collimation for linear colliders

    SciTech Connect

    Merminga, N.; Ruth, R.D.

    1990-06-01

    Experience with the SLC has indicated that backgrounds caused by the tails of the transverse beam distribution will be a serious problem for a next generation linear collider. Mechanical scrapers may not provide the best solution, because they may be damaged by the tiny, intense beams, and also because they may induce wakefield kicks large enough to cause emittance dilution. In this paper, we present a possible solution, which uses several nonlinear lenses to drive the tails of the beam to large amplitudes where they can by more easily scraped mechanically. Simulations of several different schemes are presented and evaluated with respect to effectiveness, tolerances and wakefield effects. 4 refs., 6 figs.

  15. B Physics at Hadron Colliders: Present and Future

    SciTech Connect

    Calvi, Marta

    2005-10-12

    An extensive program of B physics and CP violation measurements can be performed at Hadron Colliders. Results from the experiments CDF and DO at the Tevatron and prospects for future measurements from experiments at the LHC are presented here.

  16. Electron-Cloud Build-Up Simulations for the FNAL Main Injector

    SciTech Connect

    Furman, Miguel .A.

    2008-08-25

    We present a summary on ongoing simulation results for the electron-cloud (EC) buildup in the context of the proposed FNAL Main Injector (MI) intensity upgrade effort [1]. Most of the results presented here are for the field-free region at the location of the retarding field analyzer (RFA) electron detector [2-4]. The primary input variable we exercise is the peak secondary electron yield (SEY) {delta}{sub max}, which we let vary in the range 1.2 {le} {delta}{sub max} {le} 1.7. By combining our simulated results for the electron flux at the vacuum chamber wall with the corresponding RFA measurements we infer that 1.25 {approx}< {delta}{sub max} {approx}< 1.35 at this location. From this piece of information we estimate features of the EC distribution for various fill patterns, including the average electron number density n{sub e}. We then compare the behavior of the EC for a hypothetical RF frequency f{sub RF} = 212 MHz with the current 53 MHz for a given total beam population N{sub tot}. The density n{sub e} goes through a clear threshold as a function of N{sub tot} in a field-free region. As expected, the higher frequency leads to a weaker EC effect: the threshold in N{sub tot} is a factor {approx} 2 higher for f{sub RF} = 212 MHz than for 53 MHz, and ne is correspondingly lower by a factor {approx} 2 when N{sub tot} is above threshold. We briefly describe further work that needs to be carried out, sensitivities in the calculation, and puzzles in the results that remain to be addressed.

  17. The Muon Collider

    SciTech Connect

    Zisman, Michael S.

    2011-01-05

    We describe the scientific motivation for a new type of accelerator, the muon collider. This accelerator would permit an energy-frontier scientific program and yet would fit on the site of an existing laboratory. Such a device is quite challenging, and requires a substantial R&D program. After describing the ingredients of the facility, the ongoing R&D activities of the Muon Accelerator Program are discussed. A possible U.S. scenario that could lead to a muon collider at Fermilab is briefly mentioned.

  18. Muon collider design

    SciTech Connect

    Palmer, R. |; Sessler, A.; Skrinsky, A.

    1996-03-01

    The possibility of muon colliders was introduced by Skrinsky et al., Neuffer, and others. More recently, several workshops and collaboration meetings have greatly increased the level of discussion. In this paper we present scenarios for 4 TeV and 0.5 TeV colliders based on an optimally designed proton source, and for a lower luminosity 0.5 TeV demonstration based on an upgraded version of the AGS. It is assumed that a demonstration version based on upgrades of the FERMILAB machines would also be possible. 53 refs., 25 figs., 8 tabs.

  19. Hadron collider physics

    SciTech Connect

    Pondrom, L.

    1991-10-03

    An introduction to the techniques of analysis of hadron collider events is presented in the context of the quark-parton model. Production and decay of W and Z intermediate vector bosons are used as examples. The structure of the Electroweak theory is outlined. Three simple FORTRAN programs are introduced, to illustrate Monte Carlo calculation techniques. 25 refs.

  20. Study of new FNAL-NICADD extruded scintillator as active media of large EMCal of ALICE at LHC

    SciTech Connect

    Oleg A. Grachov et al.

    2004-05-04

    The current conceptual design of proposed Large EMCal of ALICE at LHC is based largely on the scintillating mega-tile/fiber technology implemented in CDF Endplug upgrade project and in both barrel and endcap electromagnetic calorimeters of the STAR. The cost of scintillating material leads us to the choice of extruded polystyrene based scintillator, which is available in new FNAL-NICADD facility. Result of optical measurements, such as light yield and light yield variation, show that it is possible to use this material as active media of Large EMCal of ALICE at LHC.

  1. 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.

  2. Introductory Lectures on Collider Physics

    NASA Astrophysics Data System (ADS)

    Tait, Tim M. P.; Wang, Lian-Tao

    2013-12-01

    These are elementary lectures about collider physics. They are aimed at graduate students who have some background in computing Feynman diagrams and the Standard Model, but assume no particular sophistication with the physics of high energy colliders.

  3. Search for new physics at colliders

    SciTech Connect

    Chiarelli, Giorgio; /INFN, Pisa

    2005-09-01

    In this paper I present the most recent results of the ongoing searches, mainly from Tevatron Collider experiments, for new physics beyond the Standard Model. While no signal has been seen so far, many analyses are reaching the point in which either a discovery will take place or strong limit on currently popular theories will be set.

  4. Physics Case for the International Linear Collider

    SciTech Connect

    Fujii, Keisuke; Grojean, Christophe; Peskin, Michael E.; Barklow, Tim; Gao, Yuanning; Kanemura, Shinya; Kim, Hyungdo; List, Jenny; Nojiri, Mihoko; Perelstein, Maxim; Poeschl, Roman; Reuter, Juergen; Simon, Frank; Tanabe, Tomohiko; Yu, Jaehoon; Wells, James D.; Murayama, Hitoshi; Yamamoto, Hitoshi; /Tohoku U.

    2015-06-23

    We summarize the physics case for the International Linear Collider (ILC). We review the key motivations for the ILC presented in the literature, updating the projected measurement uncertainties for the ILC experiments in accord with the expected schedule of operation of the accelerator and the results of the most recent simulation studies.

  5. Collider Tests of the Little Higgs Model

    SciTech Connect

    Burdman, Gustavo; Perelstein, Maxim; Pierce, Aaron

    2002-12-16

    The little Higgs model provides an alternative to traditional candidates for new physics at the TeV scale. The new heavy gauge bosons predicted by this model should be observable at the Large Hadron Collider (LHC). We discuss how the LHC experiments could test the little Higgs model by studying the production and decay of these particles.

  6. The Photon Collider at Tesla

    NASA Astrophysics Data System (ADS)

    Badelek, B.; Blöchinger, C.; Blümlein, J.; Boos, E.; Brinkmann, R.; Burkhardt, H.; Bussey, P.; Carimalo, C.; Chyla, J.; Çiftçi, A. K.; Decking, W.; de Roeck, A.; Fadin, V.; Ferrario, M.; Finch, A.; Fraas, H.; Franke, F.; Galynskii, M.; Gamp, A.; Ginzburg, I.; Godbole, R.; Gorbunov, D. S.; Gounaris, G.; Hagiwara, K.; Han, L.; Heuer, R.-D.; Heusch, C.; Illana, J.; Ilyin, V.; Jankowski, P.; Jiang, Y.; Jikia, G.; Jönsson, L.; Kalachnikow, M.; Kapusta, F.; Klanner, R.; Klassen, M.; Kobayashi, K.; Kon, T.; Kotkin, G.; Krämer, M.; Krawczyk, M.; Kuang, Y. P.; Kuraev, E.; Kwiecinski, J.; Leenen, M.; Levchuk, M.; Ma, W. F.; Martyn, H.; Mayer, T.; Melles, M.; Miller, D. J.; Mtingwa, S.; Mühlleitner, M.; Muryn, B.; Nickles, P. V.; Orava, R.; Pancheri, G.; Penin, A.; Potylitsyn, A.; Poulose, P.; Quast, T.; Raimondi, P.; Redlin, H.; Richard, F.; Rindani, S. D.; Rizzo, T.; Saldin, E.; Sandner, W.; Schönnagel, H.; Schneidmiller, E.; Schreiber, H. J.; Schreiber, S.; Schüler, K. P.; Serbo, V.; Seryi, A.; Shanidze, R.; da Silva, W.; Söldner-Rembold, S.; Spira, M.; Stasto, A. M.; Sultansoy, S.; Takahashi, T.; Telnov, V.; Tkabladze, A.; Trines, D.; Undrus, A.; Wagner, A.; Walker, N.; Watanabe, I.; Wengler, T.; Will, I.; Wipf, S.; Yavaş, Ö.; Yokoya, K.; Yurkov, M.; Zarnecki, A. F.; Zerwas, P.; Zomer, F.

    High energy photon colliders (γγ,γe) are based on e-e- linear colliders where high energy photons are produced using Compton scattering of laser light on high energy electrons just before the interaction point. This paper is a part of the Technical Design Report of the linear collider TESLA.1 Physics program, possible parameters and some technical aspects of the photon collider at TESLA are discussed.

  7. [Calorimeter based detectors for high energy hadron colliders]. [Progress report

    SciTech Connect

    Not Available

    1992-08-04

    This document provides a progress report on research that has been conducted under DOE Grant DEFG0292ER40697 for the past year, and describes proposed work for the second year of this 8 year grant starting November 15, 1992. Personnel supported by the contract include 4 faculty, 1 research faculty, 4 postdocs, and 9 graduate students. The work under this grant has in the past been directed in two complementary directions -- DO at Fermilab, and the second SSC detector GEM. A major effort has been towards the construction and commissioning of the new Fermilab Collider detector DO, including design, construction, testing, the commissioning of the central tracking and the central calorimeters. The first DO run is now underway, with data taking and analysis of the first events. Trigger algorithms, data acquisition, calibration of tracking and calorimetry, data scanning and analysis, and planning for future upgrades of the DO detector with the advent of the FNAL Main Injector are all involved. The other effort supported by this grant has been towards the design of GEM, a large and general-purpose SSC detector with special emphasis on accurate muon measurement over a large solid angle. This effort will culminate this year in the presentation to the SSC laboratory of the GEM Technical Design Report. Contributions are being made to the detector design, coordination, and physics simulation studies with special emphasis on muon final states. Collaboration with the RD5 group at CERN to study muon punch through and to test cathode strip chamber prototypes was begun.

  8. High luminosity muon collider design

    SciTech Connect

    Palmer, R.; Gallardo, J.

    1996-10-01

    Muon Colliders have unique technical and physics advantages and disadvantages when compared with both hadron and electron machines. They should be regarded as complementary. Parameters are given of 4 TeV high luminosity {mu}{sup +}{mu}{sup {minus}} collider, and of a 0.5 TeV lower luminosity demonstration machine. We discuss the various systems in such muon colliders.

  9. Lattice of the NICA Collider Rings

    SciTech Connect

    Sidorin, Anatoly; Kozlov, Oleg; Meshkov, Igor; Mikhaylov, Vladimir; Trubnikov, Grigoriy; Lebedev, Valeri Nagaitsev, Sergei; Senichev, Yurij; /Julich, Forschungszentrum

    2010-05-01

    The Nuclotron-based Ion Collider fAcility (NICA) is a new accelerator complex being constructed at JINR. It is designed for collider experiments with ions and protons and has to provide ion-ion (Au{sup 79+}) and ion-proton collisions in the energy range 1 {divided_by} 4.5 GeV/n and collisions of polarized proton-proton and deuteron-deuteron beams. Collider conceptions with constant {gamma}{sub tr} and with possibility of its variation are considered. The ring has the racetrack shape with two arcs and two long straight sections. Its circumference is about 450m. The straight sections are optimized to have {beta}* {approx} 35cm in two IPs and a possibility of final betatron tune adjustment.

  10. Antiproton - Ion Collider for FAIR Project

    SciTech Connect

    Beller, P.; Franzke, B.; Kienle, P.; Kruecken, R.; Koop, I.; Parkhomchuk, V.; Shatunov, Y.; Skrinsky, A.; Vostrikov, V.; Widmann, E.

    2006-03-20

    An antiproton-ion collider (AIC), with extensive using of electron cooling, is proposed to determine rms radii for protons and neutrons in unstable and short lived nuclei by means of antiproton absorption at medium energies. The experiment makes use of the electron-ion collider complex with appropriate modifications of the electron ring to store, cool and collide antiprotons of 30 MeV energy with 740 MeV/unit ions in the NESR. Antiprotons are collected, cooled, decelerated up to 30 MeV and transferred to the electron storage ring. The radioactive nuclei beams are transferred to the CR and cooled at 740A MeV and transported via the RESR to NESR, in which especially short lived nuclei are accumulated continuously to increase the luminosity. Luminosities of about 1023 cm-2s-1 may be reached with 106 ions accumulated in the NESR in coasting mode of operation, used for Schottky spectroscopy of the fragments.

  11. A New Boson with a Mass of 125 GeV Observed with the CMS Experiment at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    CMS Collabortion; Abbaneo, D.; Abbiendi, G.; Abbrescia, M.; Abdullin, S.; Abdulsalam, A.; Acharya, B. S.; Acosta, D.; Acosta, J. G.; Adair, A.; Adam, W.; Adam, N.; Adamczyk, D.; Adams, T.; Adams, M. R.; Adiguzel, A.; Adler, V.; Adolphi, R.; Adzic, P.; Afanasiev, S.; Agostino, L.; Agram, J.-L.; Aguilar-Benitez, M.; Aguilo, E.; Ahmad, M.; Ahmad, M. K. H.; Ahuja, S.; Akchurin, N.; Akgun, U.; Akgun, B.; Akin, I. V.; Alagoz, E.; Albajar, C.; Albayrak, E. A.; Albergo, S.; Albert, M.; Albrow, M.; Alcaraz Maestre, J.; Aldá Júnior, W. L.; Aldaya Martin, M.; Alemany-Fernandez, R.; Alexander, J.; Aliev, T.; Alimena, J.; Allfrey, P.; Almeida, N.; Alverson, G.; Alves, G. A.; Aly, A.; Amaglobeli, N.; Amapane, N.; Ambroglini, F.; Amsler, C.; Anagnostou, G.; Anastassov, A.; Andelin, D.; Anderson, J.; Anderson, M.; Andrea, J.; Andreev, Yu.; Andreev, V.; Andreev, V.; Andrews, W.; Anfreville, M.; Angelini, F.; Anghel, I. M.; Anisimov, A.; Anjos, T. S.; Ansari, M. H.; Antonelli, L.; Anttila, E.; Antunovic, Z.; Apanasevich, L.; Apollinari, G.; Appelt, E.; Apresyan, A.; Apyan, A.; Arce, P.; Arcidiacono, R.; Ardalan, F.; Arenton, M. W.; Arezzini, S.; Arfaei, H.; Argiro, S.; Arisaka, K.; Arndt, K.; Arneodo, M.; Arora, S.; Asavapibhop, B.; Asawatangtrakuldee, C.; Asghar, M. I.; Askew, A.; Aspell, P.; Assran, Y.; Ata, M.; Atac, M.; Attebury, G.; Attikis, A.; Auffray, E.; Autermann, C.; Auzinger, G.; Avdeeva, E.; Avery, P.; Avetisyan, A.; Avila, C.; Awad, A.; Ayan, A. S.; Azarkin, M.; Azhgirey, I.; Aziz, T.; Azzi, P.; Azzolini, V.; Azzurri, P.; Baarmand, M. M.; Babb, J.; Baccaro, S.; Bacchetta, N.; Bachtis, M.; Baden, A.; Badgett, W.; Badier, J.; Baechler, J.; Baffioni, S.; Bagaturia, I.; Bagliesi, G.; Bai, Y.; Bailleux, D.; Baillon, P.; Bainbridge, R.; Bakhshiansohi, H.; Bakirci, M. N.; Bakken, J. A.; Balazs, M.; Baldin, B.; Ball, A. H.; Ball, G.; Ballin, J.; Ban, Y.; Banerjee, S.; Banerjee, S.; Bäni, L.; Banicz, K.; Bansal, M.; Bansal, S.; Banzuzi, K.; Barashko, V.; Barbagli, G.; Barberis, E.; Barbone, L.; Barczyk, A.; Bard, R.; Barfuss, A. F.; Bargassa, P.; Barge, D.; Baringer, P.; Barker, A.; Barnes, V. E.; Barnett, B. A.; Barney, D.; Barone, L.; Barrass, T.; Bartalini, P.; Barth, C.; Bartoloni, A.; Basegmez, S.; Basso, L.; Basti, A.; Bateman, E.; Battilana, C.; Bauer, J.; Bauer, D.; Bauer, G.; Bauerdick, L. A. T.; Baulieu, G.; Baumbaugh, B.; Baumgartel, D.; Baur, U.; Bayshev, I.; Bazterra, V. E.; Bean, A.; Beauceron, S.; Beaudette, F.; Beaumont, W.; Beaupere, N.; Becheva, E.; Bedjidian, M.; Beernaert, K.; Behner, F.; Behr, J.; Behrenhoff, W.; Behrens, U.; Belforte, S.; Beliy, N.; Belknap, D.; Bell, A. J.; Bell, K. W.; Bellan, R.; Bellato, M.; Bellazzini, R.; Bellinger, J. N.; Belotelov, I.; Belyaev, A.; Belyaev, A.; Benaglia, A.; Bencze, G.; Bendavid, J.; Benedetti, D.; Benelli, G.; Benettoni, M.; Benhabib, L.; Beni, N.; Benitez, J. F.; Benussi, L.; Benvenuti, A. C.; Beranek, S.; Beretvas, A.; Bergauer, T.; Berger, J.; Bergholz, M.; Beri, S. B.; Bernardes, C. A.; Bernardini, J.; Bernardino Rodrigues, N.; Bernet, C.; Berry, D.; Berry, E.; Berryhill, J.; Bertl, W.; Bertoldi, M.; Berzano, U.; Besancon, M.; Besson, A.; Betchart, B.; Betev, B.; Bethani, A.; Betts, R. R.; Beuselinck, R.; Bhandari, V.; Bhardwaj, A.; Bhat, P. C.; Bhatnagar, V.; Bhattacharya, S.; Bhattacharya, S.; Bhatti, A.; Bheesette, S.; Bialas, W.; Bialkowska, H.; Biallass, P.; Bian, J. G.; Bianchi, G.; Bianchini, L.; Bianco, S.; Biasini, M.; Biasotto, M.; Biino, C.; Bilei, G. M.; Bilin, B.; Bilki, B.; Binkley, M.; Bisello, D.; Bitioukov, S.; Blau, B.; Blekman, F.; Blobel, V.; Bloch, D.; Bloch, P.; Bloom, K.; Bluj, M.; Blüm, P.; Blumenfeld, B.; Blyweert, S.; Boccali, T.; Bocci, A.; Bochenek, J.; Bockelman, B.; Bodek, A.; Bodin, D.; Boimska, B.; Bolla, G.; Bolognesi, S.; Bolton, T.; Bonacorsi, D.; Bonato, A.; Bondu, O.; Bonnett Del Alamo, M.; Bontenackels, M.; Boos, E.; Borcherding, F.; Bornheim, A.; Borras, K.; Borrello, L.; Bortignon, P.; Bortoletto, D.; Bose, T.; Bose, S.; Böser, C.; Bosi, F.; Bostock, F.; Botta, C.; Boudoul, G.; Bouhali, O.; Boulahouache, C.; Bourilkov, D.; Boutemeur, M.; Boutigny, D.; Boutle, S.; Bradley, D.; Braibant-Giacomelli, S.; Branca, A.; Branson, A.; Branson, J. G.; Brauer, R.; Braunschweig, W.; Breedon, R.; Breto, G.; Breuker, H.; Brew, C.; Brez, A.; Brigliadori, L.; Brigljevic, V.; Brinkerhoff, A.; Brito, L.; Broccolo, G.; Brochero Cifuentes, J. A.; Brochet, S.; Brom, J.-M.; Brona, G.; Brooke, J. J.; Broutin, C.; Brown, R. M.; Brownson, E.; Brun, H.; Bruno, G.; Buchmann, M. A.; Buchmuller, O.; Bucinskaite, I.; Budd, H.; Buege, V.; Bujak, A.; Bunichev, V.; Bunin, P.; Bunkowski, K.; Bunn, J.; Buontempo, S.; Burgmeier, A.; Burkett, K.; Busson, P.; Busza, W.; Butler, A. P. H.; Butler, P. H.; Butler, J. N.; Butt, J.; Butz, E.; Bylsma, B.; Cabrillo, I. J.; Caebergs, T.; Cai, J.; Cakir, A.; Calabria, C.; Calamba, A.; Calderon, A.; Calderon De La Barca Sanchez, M.; Cali, I. A.; Calligaris, L.; Callner, J.; Calpas, B.; Calvert, B.; Calvo, E.; Calzolari, F.; Camanzi, B.; Campagnari, C.; Campbell, A.; Campi, D.; Camporesi, T.; Candelise, V.; Cankocak, K.; Cano, E.; Capiluppi, P.; Cappello, G.; Carbone, L.; Carboni, A.; Cardaci, M.; Carlin, R.; Carlsmith, D.; Carrera Jarrin, E.; Carrillo Montoya, C. 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R.; Lamichhane, P.; Lampén, T.; Lanaro, A.; Lander, R.; Landsberg, G.; Lanev, A.; Lange, W.; Lange, J.; Lange, D.; Langenegger, U.; Lannon, K.; Lariccia, P.; Larson, K.; Lassila-Perini, K.; Lath, A.; Latronico, L.; Lawson, P.; Layter, J. G.; Lazaridis, C.; Lazic, D.; Lazo-Flores, J.; Lazzizzera, I.; Le Bihan, A.-C.; Leaver, J.; Lebeau, M.; Lebolo, L. M.; Lebourgeois, M.; Lecomte, P.; Lecoq, P.; Ledovskoy, A.; Lee, M. W.; Lee, K. S.; Lee, B.; Lee, J.; Lee, S.; Lee, Y.-J.; Lee, J.; Lee, S. J.; Lee, S. W.; Leggat, D.; Legrand, I.; Lehti, S.; Lei, Y. J.; Lelas, D.; Lellouch, J.; Lemaire, M. C.; Lemaitre, V.; Lenzi, P.; Leonard, J.; Léonard, A.; Leonardo, N.; Leonidopoulos, C.; Leonidov, A.; Leslie, D.; Lethuillier, M.; Letts, J.; Levchenko, P.; Levchuk, L.; Levin, A.; Levine, A.; Lewendel, B.; Li, W. G.; Li, W.; Li, S. W.; Li, W.; Liamsuwan, T.; Liang, D.; Liang, S.; Liao, J.; Liau, J. j.; Libeiro, T.; Lietti, S. M.; Ligabue, F.; Liko, D.; Lin, W.; Lin, S. W.; Lin, F. C.; Lin, C.; Linacre, J.; Linari, S.; Lincoln, D.; Lindén, T.; Ling, T. Y.; Lingemann, J.; Linn, S.; Lintern, A. L.; Lipton, R.; Lista, L.; Litomin, A.; Litov, L.; Litvine, V.; Litvintsev, D.; Liu, H. T.; Liu, S.; Liu, M. H.; Liu, Z. K.; Liu, H.; Liu, H.; Liu, Y. F.; Liu, C.; Liu, J. H.; Lloret Iglesias, L.; Lobelle Pardo, P.; Locci, E.; Loddo, F.; Lodge, A. B.; Lohmann, W.; Lokhtin, I.; Lomidze, D.; Lomtadze, T.; Long, O. R.; Longo, E.; Loos, R.; Lopes Pegna, D.; Lopez, A.; Lopez Perez, J. A.; Lopez Virto, A.; Lopez-Fernandez, R.; Loreti, M.; Los, S.; Loukas, D.; Lourenço, C.; Loveless, R.; Low, J. F.; Lowette, S.; Lu, Y. J.; Lu, R.-S.; Lu, Y.; Lübelsmeyer, K.; Lucaroni, A.; Luckey, P. D.; Luetic, J.; Luiggi Lopez, E.; Lujan, P.; Luk, M.; Lukyanenko, S.; Lumb, N.; Lundstedt, C.; Lungu, G.; Luo, W.; Lusin, S.; Lusito, L.; Lustermann, W.; Luthra, A.; Lutz, B.; Luukka, P.; Luyckx, S.; Lychkovskaya, N.; Lykken, J.; Lynch, S.; Lyons, L.; Ma, Y.; Ma, T.; Macneill, I.; Macpherson, A.; Madorsky, A.; Mäenpää, T.; Maes, M.; Maeshima, K.; Magaña Villalba, R.; Magass, C.; Magazzu, G.; Maggi, M.; Maggi, G.; Magini, N.; Magnan, A.-M.; Magrans de Abril, M.; Maguire, C.; Mahmoud, M. A.; Mahrous, A.; Maier, W.; Maity, M.; Majerotto, W.; Majumder, D.; Makankin, A.; Makarenko, V.; Mäki, T.; Makouski, M.; Maksimovic, P.; Malakhov, A.; Malberti, M.; Malbouisson, H.; Malcles, J.; Malek, M.; Malgeri, L.; Malhotra, S.; Malik, S.; Malik, S.; Malvezzi, S.; Mandjavidze, I.; Mangano, B.; Mankel, R.; Manna, N.; Mannelli, M.; Manolakos, I.; Mans, J.; Manthos, N.; Mantovani, G.; Manzoni, R. A.; Mao, Y.; Marage, P. E.; Marangelli, B.; Maravin, Y.; Marcellini, S.; Marchica, C.; Marchioro, A.; Marco, J.; Marco, R.; Marfin, I.; Margoni, M.; Marienfeld, M.; Marinelli, N.; Marinho, F.; Marini, A. C.; Marinov, A.; Marionneau, M.; Mariotti, C.; Markina, A.; Markou, A.; Markou, C.; Markowitz, P.; Marlow, D.; Maron, G.; Marone, M.; Maroussov, V.; Marques Pinho Noite, J.; Marraffino, J. M.; Marrouche, J.; Martelli, A.; Martin, W.; Martin, T.; Martinez, G.; Martinez Rivero, C.; Martinez Ruiz del Arbol, P.; Martínez-Ortega, J.; Martini, L.; Martins, T.; Martschei, D.; Maruyama, S.; Maselli, S.; Masetti, L.; Masetti, G.; Mason, D.; Massa, M.; Massai, M. M.; Massironi, A.; Matchev, K.; Mathez, H.; Mathias, B.; Matorras, F.; Matos Figueiredo, D.; Mattson, M.; Matveev, V.; Matveev, M.; Mavromanolakis, G.; Mavrommatis, C.; Maxa, Z.; Mazumdar, K.; Mazzoni, E.; Mazzucato, M.; McBride, P.; Mccartin, J.; McCauley, T.; McClatchey, R.; McCliment, E.; Mccoll, N.; Medvedeva, T.; Mehta, M. Z.; Mehta, P.; Meier, B.; Meier, F.; Meijers, F.; Mekterovic, D.; Melnitchenko, I.; Melo, A.; Melzer-Pellmann, I.-A.; Menasce, D.; Menchikov, A.; Mendez, H.; Meneghelli, M.; Meneguzzo, A. T.; Meng, X.; Menichelli, M.; Meola, S.; Mercadante, P. G.; Mercier, D.; Meridiani, P.; Merino, G.; Merkel, P.; Merlo, J.-P.; Mermerkaya, H.; Merola, M.; Merschmeyer, M.; Mersi, S.; Merz, J.; Meschi, E.; Meschini, M.; Mesropian, C.; Messineo, A.; Mestvirishvili, A.; Mesyats, G.; Metson, S.; Meyer, A.; Meyer, A. B.; Miceli, T.; Micheli, F.; Migliore, E.; Mignerey, A. C.; Mikulec, I.; Milenovic, P.; Militaru, O.; Millan Mejias, B.; Miller, D. G.; Miller, M. J.; Miller, D. H.; Milleret, G.; Milosevic, J.; Milstène, C.; Miné, P.; Miner, D. C.; Mirabito, L.; Mirman, N.; Mironov, C.; Mishra, K.; Missevitch, O.; Mitselmakher, G.; Mitsyn, V. V.; Miyamoto, J.; Mnich, J.; Moccia, S.; Moeller, A.; Moggi, A.; Mohammadi, A.; Mohammadi Najafabadi, M.; Mohanty, A. K.; Mohanty, G. B.; Mohapatra, A.; Mohr, N.; Moisenz, P.; Mol, X.; Molnar, J.; Mommsen, R. K.; Monaco, V.; Mondal, N. K.; Moneta, L.; Montalvo, R.; Montanari, A.; Montanino, D.; Montecassiano, F.; Moon, D. H.; Mooney, M.; Moortgat, F.; Morelos Pineda, A.; Mörmann, D.; Moromisato, J.; Moroni, L.; Morovic, S.; Morse, D. M.; Mossolov, V.; Mott, A.; Mousa, J.; Mozer, M. U.; Mrak-Tadel, A.; Mrenna, S.; Mucibello, L.; Mueller, S.; Mughal, A.; Muhl, C.; Mulders, M.; Müller, Th.; Mundim, L.; Muniz, L.; Munoz Sanchez, F. J.; Müntel, M.; Mura, B.; Murray, P.; Murray, S. J.; Murray, M.; Murzin, V.; Musella, P.; Musenich, R.; Musich, M.; Musienko, Y.; Mussgiller, A.; Muzaffar, S.; My, S.; Nachtman, J.; Nae, D.; Nägeli, C.; Nahn, S.; Naimuddin, M.; Nam, S. K.; Nandi, R.; Nappi, A.; Narain, M.; Naranjo, I. N.; Narasimham, V. S.; Nash, J.; Nash, D.; Natali, S.; Nauenberg, U.; Naujikas, R.; Naumann-Emme, S.; Navarria, F. L.; Nawrocki, K.; Nayak, A.; Nef, P.; Negri, P.; Nessi-Tedaldi, F.; Neu, C.; Neuberger, D.; Neuland, M. B.; Neumeister, N.; Newbold, D. M.; Newman, H. B.; Newman-Holmes, C.; Newsom, C. R.; Nguyen, M.; Nguyen, D.; Nguyen, H.; Nguyen, C. N.; Nicolaou, C.; Nicolas Kaufman, G.; Niegel, M.; Nikitenko, A.; Nikolic, M.; Nirunpong, K.; Nishu, N.; Nogima, H.; Noonan, D.; Norbeck, E.; Noto, F.; Nourbakhsh, S.; Novaes, S. F.; Novgorodova, O.; Nowack, A.; Nowak, F.; Noy, M.; Ntomari, E.; Nürnberg, A.; Nuttens, C.; Nuzzo, S.; Oberst, O.; Obertino, M. M.; Obraztsov, S.; O'Brien, C.; Ocalan, K.; Ocampo Rios, A. A.; Ochando, C.; Ochesanu, S.; Odeh, M.; Odell, N.; O'Dell, V.; Odorici, F.; Oehler, A.; Ofierzynski, R. A.; Oguri, V.; Oh, Y. D.; Ojalvo, I.; Oklinski, W.; Olaiya, E.; Olbrechts, A.; Oleynik, D.; Oliveros, S.; Olschewski, M.; Olsen, J.; Olson, J.; Olzem, J.; Onel, Y.; Onengut, G.; Onnela, A.; Orbaker, D.; Oreshkin, V.; Organtini, G.; Orimoto, T.; Orlov, A.; Orsini, L.; Ortega Gomez, T.; Osborne, J. A.; Osborne, I.; Osipenkov, I.; Osorio Oliveros, A. F.; Ostapchuk, A.; Otiougova, P.; Ott, J.; Otwinowski, S.; Oulianov, A.; Ozdemir, K.; Ozkorucuklu, S.; Ozok, F.; Ozpineci, A.; Ozturk, S.; Pacifico, N.; Padhi, S.; Padley, B. P.; Padula, Sandra S.; Paganini, P.; Pagano, D.; Paganoni, M.; Pakhotin, Y.; Paktinat Mehdiabadi, S.; Palencia Cortezon, E.; Palichik, V.; Palinkas, J.; Palla, F.; Palmer, C.; Palmonari, F.; Panagiotou, A.; Pandolfi, F.; Pandoulas, D.; Pansanel, J.; Pansart, J. P.; Pant, L. M.; Panwalkar, S.; Panyam, N.; Paoletti, S.; Paolucci, P.; Papacz, P.; Papadopoulos, I.; Papageorgiou, A.; Pape, L.; Paramatti, R.; Paramesvaran, S.; Parashar, N.; Parenti, A.; Parida, B.; Park, H.; Park, S. K.; Park, C.; Park, I. C.; Park, S.; Park, M.; Park, M.; Parrini, G.; Pashenkov, A.; Passaseo, M.; Passeri, D.; Pastika, N.; Pastrone, N.; Patel, R.; Patil, M. R.; Patois, Y.; Patras, V.; Patterson, J. R.; Paulini, M.; Paus, C.; Pauss, F.; Pavlov, B.; Pavlunin, V.; Pazzini, J.; Pearson, M. R.; Pearson, T.; Pedrini, D.; Pedro, K.; Pegoraro, M.; Peiffer, T.; Pela, J.; Pellett, D.; Pelliccioni, M.; Peltola, T.; Penzo, A.; Perchalla, L.; Perelygin, V.; Perera, L.; Perez, E.; Perfilov, M.; Perieanu, A.; Perloff, A.; Pernicka, M.; Peroni, C.; Perrey, H.; Perries, S.; Perrotta, A.; Perrozzi, L.; Peruzzi, M.; Pesaresi, M.; Petagna, P.; Peterman, A.; Petkov, P.; Petrakou, E.; Petridis, K.; Petrilli, A.; Petrosyan, A.; Petrov, V.; Petrucci, A.; Petrucciani, G.; Petrukhin, A.; Petrushanko, S.; Petyt, D.; Pfeiffer, D.; Pfeiffer, A.; Philipps, B.; Phillips, D.; Piasecki, C.; Piccolo, D.; Piedra Gomez, J.; Pieri, M.; Pierini, M.; Pierro, G. A.; Pieta, H.; Pietsch, N.; Pimiä, M.; Pin, A.; Pioppi, M.; Piotrzkowski, K.; Piparo, D.; Piperov, S.; Piroué, P.; Pitzl, D.; Pivarski, J.; Pivovarov, G.; Placidi, P.; Plager, C.; Planer, M.; Plestina, R.; Pol, M. E.; Polatoz, A.; Polese, G.; Polic, D.; Poll, A.; Pollack, B.; Pompili, A.; Pooth, O.; Popescu, S.; Popov, V.; Popov, A.; Pordes, R.; Poschlad, A.; Postema, H.; Postoev, V. E.; Potenza, R.; Potenza, A.; Pozdnyakov, A.; Pozniak, K.; Pozzobon, N.; Prado Da Silva, W. L.; Primavera, F.; Prokofyev, O.; Proskuryakov, A.; Prosper, H.; Ptochos, F.; Puerta Pelayo, J.; Pugliese, G.; Puigh, D.; Puljak, I.; Pullia, A.; Punz, T.; Qazi, S.; Qian, S. J.; Quan, X.; Quast, G.; Quertenmont, L.; Quintario Olmeda, A.; Rabbertz, K.; Racz, A.; Radburn-Smith, B. C.; Radi, A.; Radicci, V.; Raffaelli, F.; Ragazzi, S.; Ragghianti, G.; Raghavan, R.; Rahatlou, S.; Rahbaran, B.; Rahmat, R.; Raics, P.; Raidal, M.; Rakness, G.; Ralich, R.; Ralph, D.; Ramirez Vargas, J. E.; Rand, D.; Rander, J.; Ranieri, A.; Ranieri, R.; Ranjan, K.; Rappoccio, S.; Rapsevicius, V.; Raspereza, A.; Rathjens, D.; Ratnikov, F.; Ratnikova, N.; Ratti, S. P.; Raupach, F.; Raval, A.; Ravot, S.; Raymond, D. M.; Razis, P. A.; Rebane, L.; Rebassoo, F.; Redaelli, N.; Redjimi, R.; Redondo, I.; Reece, W.; Reeder, D.; Reid, I. D.; Reidy, J.; Reis, T.; Reithler, H.; Rekovic, V.; Remington, R.; Renker, D.; Renz, M.; Reucroft, S.; Reyes-Santos, M. A.; Reymond, J. M.; Ribeiro, P. Q.; Ribeiro Cipriano, P. M.; Ribnik, J.; Riccardi, C.; Ricci, D.; Ricci-Tam, F.; Richman, J.; Riedl, C.; Riley, D.; Rinkevicius, A.; Rizzi, A.; Ro, S. R.; Roberts, J.; Robles, J.; Robmann, P.; Röcker, S.; Rodenburg, M.; Rodozov, M.; Rodrigo, T.; Rodrigues Antunes, J.; Rodriguez, J. L.; Rodríguez-Marrero, A. Y.; Roe, J.; Roederer, F.; Rogan, C.; Rogerson, S.; Roh, Y.; Rohe, T.; Rohlf, J.; Rohringer, C.; Rohringer, H.; Roinishvili, V.; Roland, B.; Roland, C.; Roland, G.; Rolandi, G.; Romaniuk, R.; Romano, F.; Romanowska-Rybinska, K.; Romanteau, T.; Romeo, F.; Romero, L.; Romero, A.; Ron, E.; Ronchese, P.; Ronga, F. J.; Ronzhin, A.; Rose, A.; Rose, K.; Rosemann, C.; Röser, U.; Rosin, M.; Rosowsky, A.; Ross, I.; Rossato, K.; Rossi, A. M.; Rossin, R.; Rossini, M.; Rossman, P.; Rott, C.; Rougny, R.; Roumenin, C.; Rovelli, C.; Rovelli, T.; Rovere, M.; Rowe, J.; Roy, A.; Rozsa, S. G.; Rubakov, V.; Ruchti, R.; Rudolph, M.; Rugovac, S.; Ruiz-Jimeno, A.; Rumerio, P.; Rurua, L.; Rusack, R.; Rusakov, S. V.; Rush, C. J.; Ruspa, M.; Russ, J.; Rutherford, B.; Ryabov, A.; Ryan, M. J.; Ryckbosch, D.; Ryd, A.; Ryjov, V.; Ryu, G.; Ryu, S.; Ryutin, R.; Sabellek, A.; Sabes, D.; Sacchi, R.; Safarzadeh, B.; Safonov, A.; Safronov, G.; Saha, A.; Saini, L. K.; Saizu, M. A.; Saka, H.; Sakharov, A.; Sakhelashvili, T.; Sakulin, H.; Sakuma, T.; Sakumoto, W.; Sala, L.; Sala, S.; Salazar Ibarguen, H. A.; Salerno, R.; Salfeld-Nebgen, J.; Salur, S.; Salvati, E.; Sammet, J.; Samyn, D.; Sanabria, J. C.; Sanchez, A. K.; Sánchez-Hernández, A.; Sander, C.; Sanders, S.; Sanders, D. A.; Sanguinetti, G.; Sani, M.; Santanastasio, F.; Santaolalla, J.; Santocchia, A.; Santoro, A.; Saoulidou, N.; Saout, C.; Sarkar, S.; Sartirana, A.; Sarycheva, L.; Sauerland, P.; Savin, A.; Savina, M.; Savrin, V.; Sawley, M.-C.; Scarborough, T.; Schael, S.; Schäfer, C.; Schettler, H.; Scheurer, A.; Schieferdecker, D.; Schieferdecker, P.; Schilling, F.-P.; Schinzel, D.; Schizzi, A.; Schlein, P.; Schleper, P.; Schlieckau, E.; Schmanau, M.; Schmidt, R.; Schmidt, A.; Schmidt, I.; Schmitt, M.; Schmitz, D.; Schmitz, S. A.; Schnetzer, S.; Schoerner-Sadenius, T.; Schöfbeck, R.; Schott, G.; Schröder, M.; Schul, N.; Schultz von Dratzig, A.; Schum, T.; Schwerdtfeger, W.; Schwick, C.; Sciaba, A.; Scodellaro, L.; Scurlock, B.; Searle, M.; Seez, C.; Segala, M.; Segneri, G.; Segoni, I.; Sehgal, V.; Seidel, M.; Seitz, C.; Seixas, J.; Sekmen, S.; Selvaggi, M.; Selvaggi, G.; Semenov, R.; Semenov, S.; Sen, N.; Sen, S.; Sengupta, S.; Senkin, S.; Seo, H.; Serban, A. T.; Serin, M.; Servoli, L.; Sever, R.; Sexton-Kennedy, E.; Sfiligoi, I.; Sgandurra, L.; Sguazzoni, G.; Shah, M. A.; Shamdasani, J.; Shanidze, R.; Sharan, M.; Sharma, A.; Sharma, V.; Sharma, A.; Sharma, V.; Sharma, S.; Sharma, M.; Sharp, P.; Shaw, T. M.; Sheldon, P.; Shen, B. C.; Shepherd-Themistocleous, C. H.; Shevchenko, S.; Shi, X.; Shin, K.; Shipkowski, S. P.; Shipsey, I.; Shirinyants, V.; Shiu, J. G.; Shivpuri, R. K.; Shmatov, S.; Shoaib, M.; Shrestha, S.; Shreyber, I.; Shukla, P.; Shulha, S.; Shumeiko, N.; Sibille, J.; Siedling, R.; Siegrist, P.; Sigamani, M.; Sikler, F.; Silkworth, C.; Sill, A.; Silva, J.; Silva, P.; Silvers, D.; Silverwood, H.; Silvestre, C.; Silvestris, L.; Sim, K. S.; Simon, M.; Simon, S.; Simonetto, F.; Simonis, H. J.; Singh, J. B.; Singh, A. P.; Singh, G.; Singovsky, A.; Sinthuprasith, T.; Sirois, Y.; Siroli, G. P.; Sirunyan, A. M.; Skachkova, A.; Skatchkov, N.; Skhirtladze, N.; Skiba, A.; Skuja, A.; Slattery, P.; Slaunwhite, J.; Smetannikov, V.; Smiljkovic, N.; Smirnov, V.; Smirnov, I.; Smith, V. J.; Smith, B. J.; Smith, J.; Smith, J. G.; Smith, R. P.; Smith, K.; Smith, W. H.; Smolin, D.; Smoron, A.; Snigirev, A.; Snihur, R.; Snoek, H.; Snook, B.; Snow, G. R.; Snowball, M.; Soares, M. S.; Sobol, A.; Sobron Sanudo, M.; Soffi, L.; Sogut, K.; Soha, A.; Sola, V.; Solano, A.; Solin, A.; Solovey, A.; Somalwar, S.; Son, D.; Son, D. C.; Song, S.; Sonmez, N.; Sonnenschein, L.; Soomro, K.; Sordini, V.; Soroka, D.; Sorokin, P.; Souza, M. H. G.; Sowa, M.; Spagnolo, P.; Spalding, W. J.; Spandre, G.; Spanier, S.; Sparrow, A.; Speer, T.; Sperka, D.; Sphicas, P.; Spiegel, L.; Spiezia, A.; Spiga, D.; Spinoso, V.; Spiridonov, A.; Spiropulu, M.; Sprenger, D.; Sproston, M.; Squillacioti, P.; Squires, M.; Srimanobhas, N.; Stadie, H.; Stahl, A.; Staiano, A.; Starodumov, A.; Stasko, J.; Staykova, Z.; Steenberg, C.; Stefanovitch, R.; Steggemann, J.; Stein, M.; Steinbrück, G.; Stenson, K.; Stepanov, N.; Stephans, G. S. F.; Stephenson, R.; Stickland, D.; Stieger, B.; Stober, F. M.; Stöckli, F.; Stolin, V.; Stone, R.; Stoye, M.; Stoykova, S.; Stoynev, S.; Strauss, J.; Stringer, R.; Strobbe, N.; Stroiney, S.; Strom, D.; Strumia, A.; Stuart, D.; Sturdy, J.; Suarez, I.; Suarez Gonzalez, J.; Sudano, E.; Sudhakar, K.; Suh, J. S.; Sulak, L.; Sulimov, V.; Sultanov, G.; Summers, D.; Sumorok, K.; Sumowidagdo, S.; Sun, G.; Sun, H. S.; Sun, W.; Sunar Cerci, D.; Sung, K.; Surat, U. E.; Suter, H.; Svintradze, I.; Svyatkovskiy, A.; Swain, J.; Swanson, D.; Swanson, J.; Swartz, M.; Symonds, P.; Szillasi, Z.; Szleper, M.; Sznajder, A.; Szoncsó, F.; Tabarelli de Fatis, T.; Tadel, M.; Takahashi, M.; Talamo, I. G.; Tali, B.; Talov, V.; Tambe, N.; Tan, P.; Tanenbaum, W.; Tao, J.; Tapper, A.; Taroni, S.; Tatarinov, A.; Taurok, A.; Tauscher, L.; Tavernier, S.; Taylor, B. G.; Taylor, L.; Tcholakov, V.; Teller, O.; Temple, J.; Tenchini, R.; Teng, H.; Tentindo, S.; Teo, W. D.; Teodorescu, L.; Terentyev, N.; Teyssier, D.; Thea, A.; Theel, A.; Theofilatos, K.; Thiebaux, C.; Thom, J.; Thomas, L.; Thomas, M.; Thomas, S.; Thompson, J.; Thompson, R.; Thomsen, J.; Thümmel, W. H.; Thyssen, F.; Tikhonenko, E.; Tiko, A.; Timciuc, V.; Timlin, C.; Tinti, G.; Tiradani, A.; Tiras, E.; Titov, M.; Tkaczyk, S.; Tlisov, D.; To, W.; Toback, D.; Tomalin, I. R.; Tomaszewska, J.; Tonelli, G.; Tonjes, M. B.; Tonwar, S. C.; Toole, T.; Topakli, H.; Topkar, A.; Torassa, E.; Torbet, M. J.; Toropin, A.; Torre, P.; Tosi, S.; Tosi, M.; Tourneur, S.; Tourtchanovitch, L.; Traczyk, P.; Tran, N. V.; Travaglini, R.; Trayanov, R.; Treille, D.; Triantis, F. A.; Tricomi, A.; Tripathi, M.; Trocino, D.; Trocsanyi, Z. L.; Troendle, D.; Troitsky, S.; Tropea, P.; Tropiano, A.; Troshin, S.; Troska, J.; Trüb, P.; Trunov, A.; Tsamalaidze, Z.; Tsang, K. V.; Tschudi, Y.; Tsesmelis, E.; Tsirou, A.; Tu, Y.; Tucker, J.; Tully, C.; Tumanov, A.; Tumasyan, A.; Tuo, S.; Tuominen, E.; Tuominiemi, J.; Tuovinen, E.; Tupputi, S.; Turkewitz, J.; Turner, M.; Turner, P.; Tuura, L.; Tuuva, T.; Tuve, C.; Twedt, E.; Tytgat, M.; Tyurin, N.; Tzeng, Y. M.; Udriot, S.; Ueno, K.; Ujvari, B.; Ulmer, K. A.; Ulrich, R.; Unalan, Z.; Ungaro, D.; Uplegger, L.; Urscheler, C.; Uvarov, L.; Uzunian, A.; Uzunova, D.; Vaandering, E. W.; Valdata, M.; Valls, N.; Valuev, V.; Van Doninck, W.; Van Haevermaet, H.; Van Hove, P.; Van Lancker, L.; van Lingen, F.; Van Mechelen, P.; Van Mulders, P.; Van Onsem, G. P.; Van Remortel, N.; Van Spilbeeck, A.; Vander Donckt, M.; Vander Velde, C.; Vanelderen, L.; Vanhala, T. P.; Vanini, S.; Vankov, I.; Vanlaer, P.; Vardanyan, I.; Varela, J.; Varela Rodriguez, F.; Varelas, N.; Vartak, A.; Vasey, F.; Vasil'ev, S.; Vasquez Sierra, R.; Vaughan, J.; Vavilov, S.; Vazquez Acosta, M.; Vazquez Valencia, F.; Veelken, C.; Veeraraghavan, V.; Veillet, L.; Velasco, M.; Velicanu, D.; Velikzhanin, Y.; Velkovska, J.; Venditti, R.; Ventura, S.; Venturi, A.; Verdier, P.; Verdini, P. G.; Veres, G. I.; Vergili, L. N.; Vergili, M.; Verma, P.; Verrecchia, P.; Verwilligen, P.; Verzetti, M.; Veszpremi, V.; Vesztergombi, G.; Veverka, J.; Vichoudis, P.; Vidal, R.; Vidal Marono, M.; Viertel, G.; Vila, I.; Vilar Cortabitarte, R.; Vilela Pereira, A.; Villasenor-Cendejas, L. M.; Villella, I.; Vinogradov, A.; Virdee, T.; Viret, S.; Vischia, P.; Vishnevskiy, D.; Vitulo, P.; Vizan Garcia, J. M.; Vlasov, E.; Vlimant, J. R.; Vodopiyanov, I.; Vogel, H.; Voicu, B. R.; Volkov, A.; Volobouev, I.; Volodko, A.; Volpe, R.; Volyanskyy, D.; Von Goeler, E.; von Gunten, H. P.; Vorobiev, I.; Vorobyev, A.; Vorobyev, An.; Voutilainen, M.; Vuosalo, C.; Vutova, M.; Wagner, S. R.; Wagner-Kuhr, J.; Wakefield, S.; Wallny, R.; Walsh, S.; Walsh, R.; Waltenberger, W.; Walzel, G.; Wan, X.; Wang, J.; Wang, J.; Wang, X.; Wang, Z.; Wang, D.; Wang, C. C.; Wang, M.; Wardle, N.; Wasserbaech, S.; Wayand, S.; Wayne, M.; Weber, H.; Weber, M.; Weber, M.; Weber, H. A.; Weber, M.; Wehrli, L.; Wei, J. T.; Weiler, T.; Weinberg, M.; Wendland, L.; Weng, J.; Weng, Y.; Wenger, E. A.; Wenman, D.; Werner, J. S.; Wertelaers, P.; West, C.; Wetzel, J.; Whitbeck, A.; White, D.; Whitmore, J.; Whyntie, T.; Wickens, J.; Wickramage, N.; Widl, E.; Wigmans, R.; Wildish, T.; Wilken, R.; Wilkinson, R.; Williams, J. C.; Williams, T.; Williams, J. H.; Williams, G.; Willmott, C.; Wimpenny, S.; Winer, B. L.; Wingham, M.; Winn, D.; Winstrom, L.; Wissing, C.; Wittich, P.; Wittmer, B.; Wlochal, M.; Wöhri, H. K.; Wolf, R.; Wolf, M.; Womersley, W. J.; Won, S.; Wood, J. S.; Wood, D.; Wood, J.; Woodard, A.; Worm, S. D.; Wright, D.; Wrochna, G.; Wu, J. H.; Wu, S.; Wu, W.; Wulz, C.-E.; Würthwein, F.; Wyslouch, B.; Xiao, H.; Xie, S.; Xie, Z.; Xu, M.; Yagil, A.; Yang, M.; Yang, X.; Yang, Y.; Yang, F.; Yang, M.; Yang, Z. C.; Yarba, J.; Yazgan, E.; Ye, Y. L.; Yeh, P.; Yelton, J.; Yepes, P.; Yetkin, T.; Yi, K.; Yilmaz, Y.; Yohay, R.; Yoo, J.; Yoo, H. D.; Yoon, A. S.; York, A.; Youngman, C.; Yu, I.; Yu, S. S.; Yumiceva, F.; Yun, J. C.; Zabel, J.; Zabi, A.; Zablocki, J.; Zabolotny, W.; Zaganidis, N.; Zahariev, R.; Zakaria, M.; Zalan, P.; Zalewski, P.; Zanetti, M.; Zang, J.; Zang, S. L.; Zarubin, A.; Zatserklyaniy, A.; Zaytsev, V.; Zeinali, M.; Zeise, M.; Zelepoukine, S.; Zenz, S. C.; Zeuner, W. D.; Zeyrek, M.; Zhang, X.; Zhang, Z.; Zhang, Z.; Zhang, L.; Zhang, L.; Zhang, J.; Zhao, W. R.; Zheng, Y.; Zheng, Y.; Zhiltsov, V.; Zhokin, A.; Zhu, Z.; Zhu, B.; Zhu, K.; Zhu, R. Y.; Zhukov, V.; Zhukova, V.; Ziebarth, E. B.; Zielinski, M.; Zilizi, G.; Zimmerman, T.; Zito, G.; Zoeller, M. H.; Zorba, O.; Zotto, P.; Zou, W.; Zumerle, G.; Zupan, M.; Zuranski, A.; Zuyeuski, R.; Zvada, M.; Zych, P.

    2012-12-01

    The Higgs boson was postulated nearly five decades ago within the framework of the standard model of particle physics and has been the subject of numerous searches at accelerators around the world. Its discovery would verify the existence of a complex scalar field thought to give mass to three of the carriers of the electroweak force—the W+, W-, and Z0 bosons—as well as to the fundamental quarks and leptons. The CMS Collaboration has observed, with a statistical significance of five standard deviations, a new particle produced in proton-proton collisions at the Large Hadron Collider at CERN. The evidence is strongest in the diphoton and four-lepton (electrons and/or muons) final states, which provide the best mass resolution in the CMS detector. The probability of the observed signal being due to a random fluctuation of the background is about 1 in 3 × 106. The new particle is a boson with spin not equal to 1 and has a mass of about 1.25 giga-electron volts. Although its measured properties are, within the uncertainties of the present data, consistent with those expected of the Higgs boson, more data are needed to elucidate the precise nature of the new particle.

  12. A new boson with a mass of 125 GeV observed with the CMS experiment at the Large Hadron Collider.

    PubMed

    2012-12-21

    The Higgs boson was postulated nearly five decades ago within the framework of the standard model of particle physics and has been the subject of numerous searches at accelerators around the world. Its discovery would verify the existence of a complex scalar field thought to give mass to three of the carriers of the electroweak force-the W(+), W(-), and Z(0) bosons-as well as to the fundamental quarks and leptons. The CMS Collaboration has observed, with a statistical significance of five standard deviations, a new particle produced in proton-proton collisions at the Large Hadron Collider at CERN. The evidence is strongest in the diphoton and four-lepton (electrons and/or muons) final states, which provide the best mass resolution in the CMS detector. The probability of the observed signal being due to a random fluctuation of the background is about 1 in 3 × 10(6). The new particle is a boson with spin not equal to 1 and has a mass of about 125 [corrected] giga-electron volts. Although its measured properties are, within the uncertainties of the present data, consistent with those expected of the Higgs boson, more data are needed to elucidate the precise nature of the new particle. PMID:23258887

  13. Physics and Analysis at a Hadron Collider - An Introduction (1/3)

    ScienceCinema

    None

    2011-10-06

    This is the first lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This first lecture provides a brief introduction to hadron collider physics and collider detector experiments as well as offers some analysis guidelines. The lectures are aimed at graduate students.

  14. 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.

  15. Bouncing and Colliding Branes

    SciTech Connect

    Lehners, Jean-Luc

    2007-11-20

    In a braneworld description of our universe, we must allow for the possibility of having dynamical branes around the time of the big bang. Some properties of such domain walls in motion are discussed here, for example the ability of negative-tension domain walls to bounce off spacetime singularities and the consequences for cosmological perturbations. In this context, we will also review a colliding branes solution of heterotic M-theory that has been proposed as a model for early universe cosmology.

  16. Muon Collider Progress: Accelerators

    SciTech Connect

    Zisman, Michael S.

    2011-09-10

    A muon collider would be a powerful tool for exploring the energy-frontier with leptons, and would complement the studies now under way at the LHC. Such a device would offer several important benefits. Muons, like electrons, are point particles so the full center-of-mass energy is available for particle production. Moreover, on account of their higher mass, muons give rise to very little synchrotron radiation and produce very little beamstrahlung. The first feature permits the use of a circular collider that can make efficient use of the expensive rf system and whose footprint is compatible with an existing laboratory site. The second feature leads to a relatively narrow energy spread at the collision point. Designing an accelerator complex for a muon collider is a challenging task. Firstly, the muons are produced as a tertiary beam, so a high-power proton beam and a target that can withstand it are needed to provide the required luminosity of ~1 × 10{sup 34} cm{sup –2}s{sup –1}. Secondly, the beam is initially produced with a large 6D phase space, which necessitates a scheme for reducing the muon beam emittance (“cooling”). Finally, the muon has a short lifetime so all beam manipulations must be done very rapidly. The Muon Accelerator Program, led by Fermilab and including a number of U.S. national laboratories and universities, has undertaken design and R&D activities aimed toward the eventual construction of a muon collider. Design features of such a facility and the supporting R&D program are described.

  17. COLLIDING CRYSTALLINE BEAMS.

    SciTech Connect

    WEI, J.

    1998-06-26

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. We study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. We initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then overlapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, we find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong cooling, although theoretically achievable, is a challenge in practice.

  18. Colliding Crystalline Beams

    SciTech Connect

    Wei, Jie; Sessler, A.M.

    1998-06-01

    The understanding of crystalline beams has advanced to the point where one can now, with reasonable confidence, undertake an analysis of the luminosity of colliding crystalline beams. Such a study is reported here. It is necessary to observe the criteria, previously stated, for the creation and stability of crystalline beams. This requires, firstly, the proper design of a lattice. Secondly, a crystal must be formed, and this can usually be done at various densities. Thirdly, the crystals in a colliding-beam machine are brought into collision. We study all of these processes using the molecular dynamics (MD) method. The work parallels what was done previously, but the new part is to study the crystal-crystal interaction in collision. We initially study the zero-temperature situation. If the beam-beam force (or equivalent tune shift) is too large then over-lapping crystals can not be created (rather two spatially separated crystals are formed). However, if the beam-beam force is less than but comparable to that of the space-charge forces between the particles, we find that overlapping crystals can be formed and the beam-beam tune shift can be of the order of unity. Operating at low but non-zero temperature can increase the luminosity by several orders of magnitude over that of a usual collider. The construction of an appropriate lattice, and the development of adequately strong coding, although theoretically achievable, is a challenge in practice.

  19. Scintillating Fibre Tracking at High Luminosity Colliders

    NASA Astrophysics Data System (ADS)

    Joram, C.; Haefeli, G.; Leverington, B.

    2015-08-01

    The combination of small diameter scintillating plastic fibres with arrays of SiPM photodetectors has led to a new class of SciFi trackers usable at high luminosity collider experiments. After a short review of the main principles and history of the scintillating fibre technology, we describe the challenges and developments of the large area Scintillating Fibre Tracker currently under development for the upgraded LHCb experiment.

  20. The performance of the Tevatron collider at Fermilab

    SciTech Connect

    Gelfand, N.M.

    1991-10-01

    This paper will describe the actual operating performance of the Tevatron, operating as a collider, and will indicate the planned upgrades which will enhance, the physics results coming from the experiments being performed at Fermilab.

  1. Optimization of a closed-loop gas system for the operation of Resistive Plate Chambers at the Large Hadron Collider experiments

    NASA Astrophysics Data System (ADS)

    Capeans, M.; Glushkov, I.; Guida, R.; Hahn, F.; Haider, S.

    2012-01-01

    Resistive Plate Chambers (RPCs), thanks to their fast time resolution (˜1 ns), suitable space resolution (˜1 cm) and low production cost (˜50 €/m2), are widely employed for the muon trigger systems at the Large Hadron Collider (LHC). Their large detector volume (they cover a surface of about 4000 m2 equivalent to 16 m3 of gas volume both in ATLAS and CMS) and the use of a relatively expensive Freon-based gas mixture make a closed-loop gas circulation unavoidable. It has been observed that the return gas of RPCs operated in conditions similar to the difficult experimental background foreseen at LHC contains a large amount of impurities potentially dangerous for long-term operation. Several gas-cleaning agents are currently in use in order to avoid accumulation of impurities in the closed-loop circuits. We present the results of a systematic study characterizing each of these cleaning agents. During the test, several RPCs were operated at the CERN Gamma Irradiation Facility (GIF) in a high radiation environment in order to observe the production of typical impurities: mainly fluoride ions, molecules of the Freon group and hydrocarbons. The polluted return gas was sent to several cartridges, each containing a different cleaning agent. The effectiveness of each material was studied using gas chromatography and mass-spectrometry techniques. Results of this test have revealed an optimized configuration of filters that is now under long-term validation.Gas optimization studies are complemented with a finite element simulation of gas flow distribution in the RPCs, aiming at its eventual optimization in terms of distribution and flow rate.

  2. XXth Hadron Collider Physics Symposium

    NASA Astrophysics Data System (ADS)

    In 2009, the Hadron Collider Physics Symposium took place in Evian (France), on the shore of the Geneva Lake, from 16-20 November. It was jointly organised by CERN and the French HEP community (CNRS-IN2P3 and CEA-IRFU). This year's symposium come at an important time for both the Tevatron and LHC communities. It stimulated the completion of analyses for a significant Tevatron data sample, and it allowed an in-depth review of the readiness of the LHC and its detectors just before first collisions. The programme includes sessions on top-quark and electro-weak physics, QCD, B physics, new phenomena, electro-weak symmetry breaking, heavy ions, and the status and commissioning of the LHC machine and its experiments. Conference website : http://hcp2009.in2p3.fr/

  3. Collider searches for extra dimensions

    SciTech Connect

    Landsberg, Greg; /Brown U.

    2004-12-01

    Searches for extra spatial dimensions remain among the most popular new directions in our quest for physics beyond the Standard Model. High-energy collider experiments of the current decade should be able to find an ultimate answer to the question of their existence in a variety of models. Until the start of the LHC in a few years, the Tevatron will remain the key player in this quest. In this paper, we review the most recent results from the Tevatron on searches for large, TeV{sup -1}-size, and Randall-Sundrum extra spatial dimensions, which have reached a new level of sensitivity and currently probe the parameter space beyond the existing constraints. While no evidence for the existence of extra dimensions has been found so far, an exciting discovery might be just steps away.

  4. Artist rendering of dust grains colliding at low speeds

    NASA Technical Reports Server (NTRS)

    2003-01-01

    Clues to the formation of planets and planetary rings -- like Saturn's dazzling ring system -- may be found by studying how dust grains interact as they collide at low speeds. To study the question of low-speed dust collisions, NASA sponsored the COLLisions Into Dust Experiment (COLLIDE) at the University of Colorado. It was designed to spring-launch marble-size projectiles into trays of powder similar to space or lunar dust. COLLIDE-1 (1998) discovered that collisions below a certain energy threshold eject no material. COLLIDE-2 was designed to identify where the threshold is. In COLLIDE-2, scientists nudged small projectiles into dust beds and recorded how the dust splashed outward (video frame at top; artist's rendering at bottom). The slowest impactor ejected no material and stuck in the target. The faster impactors produced ejecta; some rebounded while others stuck in the target.

  5. PERFORMANCE LIMITATIONS IN HIGH-ENERGY ION COLLIDERS

    SciTech Connect

    FISCHER, W.

    2005-05-16

    High-energy ion colliders (hadron colliders operating with ions other than protons) are premier research tools for nuclear physics. The collision energy and high luminosity are important design and operations considerations. The experiments also expect flexibility with frequent changes in the collision energy, detector fields, and ion species, including asymmetric collisions. For the creation, acceleration, and storage of bright intense ion beams limits are set by space charge, charge exchange, and intrabeam scattering effects. The latter leads to luminosity lifetimes of only a few hours for intense heavy ions beams. Currently, the Relativistic Heavy Ion Collider (RHIC) at BNL is the only operating high-energy ion collider. Later this decade the Large Hadron Collider (LHC), under construction at CERN, will also run with heavy ions.

  6. New DIS and collider results on PDFs

    SciTech Connect

    Rizvi, E.

    2015-05-15

    The HERA ep collider experiments have measured the proton structure functions over a wide kinematic range. New data from the H1 experiment now extend the range to higher 4-momentum transfer (√(Q{sup 2})) over which a precision of ∼ 2% is achieved in the neutral current channel. A factor of two reduction in the systematic uncertainties over previous measurement is attained. The charged current structure function measurements are also significantly improved in precision. These data, when used in QCD analyses of the parton density functions (PDFs) reduce the PDF uncertainties particularly at high momentum fractions x which is relevant to low energy neutrino scattering cross sections. New data from the LHC pp collider experiments may also offer significant high x PDF improvements as the experimental uncertainties improve.

  7. Colliding nuclei to colliding galaxies: Illustrations using a simple colliding liquid-drop apparatus

    NASA Astrophysics Data System (ADS)

    Becchetti, F. D.; Mack, S. L.; Robinson, W. R.; Ojaruega, M.

    2015-10-01

    A simple apparatus suitable for observing the collisions between drops of fluids of various properties is described. Typical results are shown for experiments performed by undergraduate students using various types of fluids. The collisions take place under free-fall (zero-g) conditions, with analysis employing digital video. Two specific types of collisions are examined in detail, head-on collisions and peripheral, grazing collisions. The collisions for certain fluids illustrate many types of nuclear collisions and provide useful insight into these processes, including both fusion and non-fusion outcomes, often with the formation of exotic shapes or emission of secondary fragments. Collisions of other liquids show a more chaotic behavior, often resembling galactic collisions. As expected, the Weber number associated with a specific collision impact parameter is found to be the important quantity in determining the initial outcome of these colliding systems. The features observed resemble those reported by others using more elaborate experimental techniques.

  8. Hadron-hadron colliders

    SciTech Connect

    Month, M.; Weng, W.T.

    1983-06-21

    The objective is to investigate whether existing technology might be extrapolated to provide the conceptual framework for a major hadron-hadron collider facility for high energy physics experimentation for the remainder of this century. One contribution to this large effort is to formalize the methods and mathematical tools necessary. In this report, the main purpose is to introduce the student to basic design procedures. From these follow the fundamental characteristics of the facility: its performance capability, its size, and the nature and operating requirements on the accelerator components, and with this knowledge, we can determine the technology and resources needed to build the new facility.

  9. The super collider revisited

    SciTech Connect

    Hussein, M.S.; Pato, M.P. )

    1992-05-20

    In this paper, the authors suggest a revised version of the Superconducting Super Collider (SSC) that employs the planned SSC first stage machine as an injector of 0.5 TeV protons into a power laser accelerator. The recently developed Non-linear Amplification of Inverse Bremsstrahlung Acceleration (NAIBA) concept dictates the scenario of the next stage of acceleration. Post Star Wars lasers, available at several laboratories, can be used for the purpose. The 40 TeV CM energy, a target of the SSC, can be obtained with a new machine which can be 20 times smaller than the planned SSC.

  10. Muon Colliders and Neutrino Factories

    SciTech Connect

    Geer, Steve; /Fermilab

    2009-11-01

    Over the past decade, there has been significant progress in developing the concepts and technologies needed to produce, capture, and accelerate {Omicron}(10{sup 21}) muons per year. These developments have paved the way for a new type of neutrino source (neutrino factory) and a new type of very high energy lepton-antilepton collider (muon collider). This article reviews the motivation, design, and research and development for future neutrino factories and muon colliders.

  11. Muon colliders and neutrino factories

    SciTech Connect

    Geer, S.; /Fermilab

    2010-09-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture and accelerate {Omicron}(10{sup 21}) muons/year. This development prepares the way for a new type of neutrino source (Neutrino Factory) and a new type of very high energy lepton-antilepton collider (Muon Collider). This article reviews the motivation, design and R&D for Neutrino Factories and Muon Colliders.

  12. Muon Colliders and Neutrino Factories *

    NASA Astrophysics Data System (ADS)

    Geer, Steve

    2009-11-01

    Over the past decade, there has been significant progress in developing the concepts and technologies needed to produce, capture, and accelerate O(1021) muons per year. These developments have paved the way for a new type of neutrino source (neutrino factory) and a new type of very high energy lepton-antilepton collider (muon collider). This article reviews the motivation, design, and research and development for future neutrino factories and muon colliders.

  13. Linear collider development at SLAC

    SciTech Connect

    Irwin, J.

    1993-08-01

    Linear collider R&D at SLAC comprises work on the present Stanford Linear Collider (SLC) and work toward the next linear collider (NLC). Recent SLC developments are summarized. NLC studies are divided into hardware-based and theoretical. We report on the status of the NLC Test Accelerator (NLCTA) and the final focus test beam (FFTB), describe plans for ASSET, an installation to measure accelerator structure wakefields, and mention IR design developments. Finally we review recent NLC theoretical studies, ending with the author`s view of next linear collider parameter sets.

  14. Future Accelerators, Muon Colliders, and Neutrino Factories

    SciTech Connect

    Richard A Carrigan, Jr.

    2001-12-19

    Particle physics is driven by five great topics. Neutrino oscillations and masses are now at the fore. The standard model with extensions to supersymmetry and a Higgs to generate mass explains much of the field. The origins of CP violation are not understood. The possibility of extra dimensions has raised tantalizing new questions. A fifth topic lurking in the background is the possibility of something totally different. Many of the questions raised by these topics require powerful new accelerators. It is not an overstatement to say that for some of the issues, the accelerator is almost the experiment. Indeed some of the questions require machines beyond our present capability. As this volume attests, there are parts of the particle physics program that have been significantly advanced without the use of accelerators such as the subject of neutrino oscillations and many aspects of the particle-cosmology interface. At this stage in the development of physics, both approaches are needed and important. This chapter first reviews the status of the great accelerator facilities now in operation or coming on within the decade. Next, midrange possibilities are discussed including linear colliders with the adjunct possibility of gamma-gamma colliders, muon colliders, with precursor neutrino factories, and very large hadron colliders. Finally visionary possibilities are considered including plasma and laser accelerators.

  15. Linear Collider Physics Resource Book Snowmass 2001

    SciTech Connect

    Ronan , M.T.

    2001-06-01

    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 decade 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

  16. Results from hadron colliders

    SciTech Connect

    Pondrom, L.G. )

    1990-12-14

    The present status of hadron collider physics is reviewed. The total cross section for {bar p} + p has been measured at 1.8 TeV: {sigma}{sub tot} = 72.1 {plus minus} 3.3 mb. New data confirm the UA2 observation of W/Z {yields} {bar q}q. Precision measurements of M{sub W} by UA2 and CDF give an average value M{sub W} = 80.13 {plus minus} 0.30 GeV/c{sup 2}. When combined with measurements of M{sub Z} from LEP and SLC this number gives sin{sup 2}{theta}{sub W} = 0.227 {plus minus} 0.006, or m{sub top} = 130{sub {minus}60}{sup +40} GeV/c{sup 2} from the EWK radiative correction term {Delta}r. Evidence for hadron colliders as practical sources of b quarks has been strengthened, while searches for t quarks have pushed the mass above M{sub W}: m{sub top} > 89 GeV/c{sup 2} 95% cl (CDF Preliminary). Searches beyond the standard model based on the missing E{sub T} signature have not yet produced any positive results. Future prospects for the discovery of the top quark in the range m{sub top} < 200 GeV/c{sup 2} look promising. 80 refs., 35 figs., 7 tabs.

  17. Current experiments in elementary particle physics. Revision

    SciTech Connect

    Galic, H.; Armstrong, F.E.; von Przewoski, B.

    1994-08-01

    This report contains summaries of 568 current and recent experiments in elementary particle physics. Experiments that finished taking data before 1988 are excluded. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, INS (Tokyo), ITEP (Moscow), IUCF (Bloomington), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several underground and underwater experiments. Instructions are given for remote searching of the computer database (maintained under the SLAC/SPIRES system) that contains the summaries.

  18. Contribution of inverse gluon emission to QCD corrections to the Drell-Yan process for experiments at the large hadron collider (LHC)

    SciTech Connect

    Zykunov, V. A.

    2011-01-15

    The contributions of inverse gluon emission to the lowest order QCD corrections to the Drell-Yan process for future experiments at LHC are calculated. The use of fully differential cross sections makes it possible to apply readily the results of these calculations for experimental purposes (in correcting data from future experiments at LHC). It is shown analytically that the present results are independent of the quark mass. A numerical analysis of respective radiative effects is performed by means of the READY FORTRAN code with allowance for the experimental cuts used at the Compact Muon Solenoid (CMS) detector.

  19. TOP AND HIGGS PHYSICS AT THE HADRON COLLIDERS

    SciTech Connect

    Jabeen, Shabnam

    2013-10-20

    This review summarizes the recent results for top quark and Higgs boson measurements from experiments at Tevatron, a proton–antiproton collider at a center-of-mass energy of √ s =1 . 96 TeV, and the Large Hadron Collider, a proton–proton collider at a center- of-mass energy of √ s = 7 TeV. These results include the discovery of a Higgs-like boson and measurement of its various properties, and measurements in the top quark sector, e.g. top quark mass, spin, charge asymmetry and production of single top quark.

  20. Longitudinal damping in the Tevatron collider

    SciTech Connect

    Kerns, Q.A.; Jackson, G.; Kerns, C.R.; Miller, H.; Reid, J.; Siemann, R.; Wildman, D.

    1989-03-01

    This paper describes the damper design for 6 proton on 6 pbar bunches in the Tevatron collider. Signal pickup, transient phase detection, derivative networks, and phase correction via the high-level rf are covered. Each rf station is controlled by a slow feedback loop. In addition, global feedback loops control each set of four cavities, one set for protons and one set for antiprotons. Operational experience with these systems is discussed. 7 refs., 9 figs.

  1. Top physics at the Tevatron Collider

    SciTech Connect

    Margaroli, Fabrizio; /Purdue U.

    2007-10-01

    The top quark has been discovered in 1995 at the CDF and DO experiments located in the Tevatron ring at the Fermilab laboratory. After more than a decade the Tevatron collider, with its center-of-mass energy collisions of 1.96 TeV, is still the only machine capable of producing such exceptionally heavy particle. Here I present a selection of the most recent CDF and DO measurements performed analyzing {approx} 1 fb{sup -1} of integrated luminosity.

  2. Accelerator Test Facility for Muon Collider and Neutrino Factory R&d

    NASA Astrophysics Data System (ADS)

    Shiltsev, Vladimir

    2010-06-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture, accelerate and collide high intensity beams of muons. At present, a high-luminosity multi-TeV muon collider presents a viable option for the next generation lepton-lepton collider, which is believed to be needed to fully explore high energy physics in the era following LHC discoveries. This article briefly reviews the needs and possibilities for a Muon Collider beam test facility to carry out the R&D program on the collider front-end and 6D cooling demonstration experiment.

  3. Composite leptoquarks in hadronic colliders

    SciTech Connect

    Eboli, O.J.P.; Olinto, A.V.

    1988-12-01

    We study the production of composite scalar leptoquarks in hadronic colliders (CERN p-barp, Fermilab Tevatron p-barp, and the Superconducting Super Collider pp). We examine its direct single production via qg..-->..l+leptoquark, and its effect on the production of lepton pairs (p/sup (-)/p..-->..l/sup +/l/sup -/).

  4. ALPs at colliders

    NASA Astrophysics Data System (ADS)

    Mimasu, Ken; Sanz, Verónica

    2015-06-01

    New pseudo-scalars, often called axion-like particles (ALPs), abound in model-building and are often associated with the breaking of a new symmetry. Traditional searches and indirect bounds are limited to light axions, typically in or below the KeV range for ALPs coupled to photons. We present collider bounds on ALPs from mono-γ, tri-γ and mono-jet searches in a model independent fashion, as well as the prospects for the LHC and future machines. We find that they are complementary to existing searches, as they are sensitive to heavier ALPs and have the capability to cover an otherwise inaccessible region of parameter space. We also show that, assuming certain model dependent correlations between the ALP coupling to photons and gluons as well as considering the validity of the effective description of ALP interactions, mono-jet searches are in fact more suitable and effective in indirectly constraining ALP scenarios.

  5. Positrons for linear colliders

    SciTech Connect

    Ecklund, S.

    1987-11-01

    The requirements of a positron source for a linear collider are briefly reviewed, followed by methods of positron production and production of photons by electromagnetic cascade showers. Cross sections for the electromagnetic cascade shower processes of positron-electron pair production and Compton scattering are compared. A program used for Monte Carlo analysis of electromagnetic cascades is briefly discussed, and positron distributions obtained from several runs of the program are discussed. Photons from synchrotron radiation and from channeling are also mentioned briefly, as well as positron collection, transverse focusing techniques, and longitudinal capture. Computer ray tracing is then briefly discussed, followed by space-charge effects and thermal heating and stress due to showers. (LEW)

  6. Colliding Beam Fusion Reactors

    NASA Astrophysics Data System (ADS)

    Rostoker, Norman; Qerushi, Artan; Binderbauer, Michl

    2003-06-01

    The recirculating power for virtually all types of fusion reactors has previously been calculated [1] with the Fokker-Planck equation. The reactors involve non-Maxwellian plasmas. The calculations are generic in that they do not relate to specific confinement devices. In all cases except for a Tokamak with D-T fuel the recirculating power was found to exceed the fusion power by a large factor. In this paper we criticize the generality claimed for this calculation. The ratio of circulating power to fusion power is calculated for the Colliding Beam Reactor with fuels D-T, D-He3 and p-B11. The results are respectively, 0.070, 0.141 and 0.493.

  7. When Worlds Collide

    SciTech Connect

    Chang, Spencer; Kleban, Matthew; Levi, Thomas S E-mail: mk161@nyu.edu

    2008-04-15

    We analyze the cosmological signatures visible to an observer in a Coleman-de Luccia bubble when another such bubble collides with it. We use a gluing procedure to generalize the results of Freivogel, Horowitz and Shenker to the case of a general cosmological constant in each bubble and study the resulting spacetimes. The collision breaks the isotropy and homogeneity of the bubble universe and provides a cosmological 'axis of evil' which can affect the cosmic microwave background in several unique and potentially detectable ways. Unlike more conventional perturbations to the inflationary initial state, these signatures can survive even relatively long periods of inflation. In addition, we find that for a given collision the observers in the bubble with smaller cosmological constant are safest from collisions with domain walls, possibly providing another anthropic selection principle for small positive vacuum energy.

  8. A model for computing at the SSC (Superconducting Super Collider)

    SciTech Connect

    Baden, D. . Dept. of Physics); Grossman, R. . Lab. for Advanced Computing)

    1990-06-01

    High energy physics experiments at the Superconducting Super Collider (SSC) will show a substantial increase in complexity and cost over existing forefront experiments, and computing needs may no longer be met via simple extrapolations from the previous experiments. We propose a model for computing at the SSC based on technologies common in private industry involving both hardware and software. 11 refs., 1 fig.

  9. Introduction to colliding beams at Fermilab

    SciTech Connect

    Thompson, J.

    1994-10-01

    The Fermi National Accelerator Laboratory is currently the site of the world`s highest center-of-mass energy proton-antiproton colliding beam accelerator, the Tevatron. The CDF and D{O} detectors each envelop one of two luminous regions in the collider, and are thus wholly dependent on the accelerator for their success. The Tevatron`s high operating energy, reliability, and record setting integrated luminosity have allowed both experiments to make world-class measurements and defined the region of physics that each can explore. The following sections are an overview of the highlights of the accelerator operation and are compiled from many sources. The major sources for each section are listed at the beginning of that section.

  10. Collider signature of T-quarks

    SciTech Connect

    Carena, Marcela; Hubisz, Jay; Perelstein, Maxim; Verdier, Patrice; /Lyon, IPN

    2006-10-01

    Little Higgs models with T Parity contain new vector-like fermions, the T-odd quarks or ''T-quarks'', which can be produced at hadron colliders with a QCD-strength cross section. Events with two acoplanar jets and large missing transverse energy provide a simple signature of T-quark production. We show that searches for this signature with the Tevatron Run II data can probe a significant part of the Little Higgs model parameter space not accessible to previous experiments, exploring T-quark masses up to about 400 GeV. This reach covers parts of the parameter space where the lightest T-odd particle can account for the observed dark matter relic abundance. We also comment on the prospects for this search at the Large Hadron Collider (LHC).

  11. The CERN SPS proton-antiproton collider

    NASA Astrophysics Data System (ADS)

    Schmidt, Rudiger

    One of CERN's most ambitious and successful projects was the search for the intermediate bosons, W and Z [1]. The accelerator part of the project relied on a number of innovations in accelerator physics and technology. The invention of the method of stochastic cooling and the extension by many orders of magnitude beyond the initial proof of principle demonstration allowed the construction of the Antiproton Accumulator. Major modifications to the 26 GeV PS complex and the conversion of the 300 GeV SPS, which had just started up as an accelerator, to a pbar p collider were required. The SPS collider had to master the beam-beam effect far beyond limits reached before and had to function in a tight symbiosis with the UA1 and UA2 experiments.

  12. Quantum-beamsstrahlung laser collider

    SciTech Connect

    Tajima, T.; Chattopadyay, S.; Xie, M.

    1997-11-01

    An e{sup +}e{sup {minus}} linear collider at energies beyond a TeV runs into a problem of severe beamsstrahlung, characterized by {Upsilon} on the order of unity (and beyond). In the regime of extremely high {Upsilon} the beamsstrahlung may be largely suppressed due to the quantum effect. In the design of an e{sup +}e{sup {minus}} collider there are two ways to satisfy the collider physics constraints. One is to decrease the number of particles per bunch (and thus to increase the repetition rate) and the other is to decrease the longitudinal bunch length. The former approach can limit {Upsilon}, while the latter boosts it. (It may be useful to reevaluate the future collider parameters in view of this.) The laser wakefield driver for a collider in comparison with the microwave driver naturally offers a very short bunch length, which is appropriate for the latter collider option. The authors show that this choice of collider design with a short bunch length and high {Upsilon} has advantages and provide sample design parameters at 5 TeV. Such sample design parameters challenge them in a number of fronts, such as the preservation of high quality bunches, efficient high repetition rate lasers, etc. The collision point physics simulated by the CAIN code shows a surprisingly well preserved luminosity spectrum.

  13. Object based data access at the D0 experiment

    SciTech Connect

    Fuess, S.; D0 Collaboration

    1995-11-01

    The D{O} Experiment at Fermilab is currently participating in the FNAL Computing Division`s ``Computing for Analysis Project`` (CAP) to investigate object based data storage and access. Following a short description of the CAP system architecture, the D{O} data model is explored. A brief discussion of the method of operation of the CAP system leads into a concluding section.

  14. The standard model and colliders

    SciTech Connect

    Hinchliffe, I.

    1987-03-01

    Some topics in the standard model of strong and electroweak interactions are discussed, as well as how these topics are relevant for the high energy colliders which will become operational in the next few years. The radiative corrections in the Glashow-Weinberg-Salam model are discussed, stressing how these corrections may be measured at LEP and the SLC. CP violation is discussed briefly, followed by a discussion of the Higgs boson and the searches which are relevant to hadron colliders are then discussed. Some of the problems which the standard model does not solve are discussed, and the energy ranges accessible to the new colliders are indicated. (LEW)

  15. Hadron collider physics at UCR

    SciTech Connect

    Kernan, A.; Shen, B.C.

    1997-07-01

    This paper describes the research work in high energy physics by the group at the University of California, Riverside. Work has been divided between hadron collider physics and e{sup +}-e{sup {minus}} collider physics, and theoretical work. The hadron effort has been heavily involved in the startup activities of the D-Zero detector, commissioning and ongoing redesign. The lepton collider work has included work on TPC/2{gamma} at PEP and the OPAL detector at LEP, as well as efforts on hadron machines.

  16. 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.

  17. Radiation damage in the diamond based beam condition monitors of the CMS experiment at the Large Hadron Collider (LHC) at CERN

    NASA Astrophysics Data System (ADS)

    Guthoff, Moritz; Afanaciev, Konstantin; Dabrowski, Anne; de Boer, Wim; Lange, Wolfgang; Lohmann, Wolfgang; Stickland, David

    2013-12-01

    The Beam Condition Monitor (BCM) of the CMS detector at the LHC is a protection device similar to the LHC Beam Loss Monitor system. While the electronics used is the same, poly-crystalline Chemical Vapor Deposition (pCVD) diamonds are used instead of ionization chambers as the BCM sensor material. The main purpose of the system is the protection of the silicon Pixel and Strip tracking detectors by inducing a beam dump, if the beam losses are too high in the CMS detector. By comparing the detector current with the instantaneous luminosity, the BCM detector efficiency can be monitored. The number of radiation-induced defects in the diamond, reduces the charge collection distance, and hence lowers the signal. The number of these induced defects can be simulated using the FLUKA Monte Carlo simulation. The cross-section for creating defects increases with decreasing energies of the impinging particles. This explains, why diamond sensors mounted close to heavy calorimeters experience more radiation damage, because of the high number of low energy neutrons in these regions. The signal decrease was stronger than expected from the number of simulated defects. Here polarization from trapped charge carriers in the defects is a likely candidate for explaining the difference, as suggested by Transient Current Technique (TCT) measurements. A single-crystalline (sCVD) diamond sensor shows a faster relative signal decrease than a pCVD sensor mounted at the same location. This is expected, since the relative increase in the number of defects is larger in sCVD than in pCVD sensors.

  18. Neutrino alternatives for missing energy events at colliders

    SciTech Connect

    Chang, Spencer; Gouvea, Andre de

    2009-07-01

    If the dark matter consists of a weakly interacting massive particle, it can be produced and studied at future collider experiments like those at the LHC. The production of collider-stable weakly interacting massive particles is characterized by hard scattering events with large missing transverse energy. Here we emphasize and discuss the fact that the discovery of events inconsistent with the standard model with large missing transverse energy need not point to the existence of new, collider-stable particles. We explore an alternative explanation where the only sources of missing transverse energy are standard model neutrinos. We present concrete examples of such scenarios, focusing on supersymmetric models with R-parity violation. We also discuss means of differentiating neutrino missing energy signals from the production of new collider-stable particles. These include both model-dependent signals, such as particle tags and flavor counts, as well as model-independent tests that attempt to measure the missing particle mass.

  19. When Black Holes Collide

    NASA Technical Reports Server (NTRS)

    Baker, John

    2010-01-01

    Among the fascinating phenomena predicted by General Relativity, Einstein's theory of gravity, black holes and gravitational waves, are particularly important in astronomy. Though once viewed as a mathematical oddity, black holes are now recognized as the central engines of many of astronomy's most energetic cataclysms. Gravitational waves, though weakly interacting with ordinary matter, may be observed with new gravitational wave telescopes, opening a new window to the universe. These observations promise a direct view of the strong gravitational dynamics involving dense, often dark objects, such as black holes. The most powerful of these events may be merger of two colliding black holes. Though dark, these mergers may briefly release more energy that all the stars in the visible universe, in gravitational waves. General relativity makes precise predictions for the gravitational-wave signatures of these events, predictions which we can now calculate with the aid of supercomputer simulations. These results provide a foundation for interpreting expect observations in the emerging field of gravitational wave astronomy.

  20. The Relativistic Heavy Ion Collider

    NASA Astrophysics Data System (ADS)

    Fischer, Wolfram

    The Relativistic Heavy Ion Collider (RHIC), shown in Fig. 1, was build to study the interactions of quarks and gluons at high energies [Harrison, Ludlam and Ozaki (2003)]. The theory of Quantum Chromodynamics (QCD) describes these interactions. One of the main goals for the RHIC experiments was the creation and study of the Quark-Gluon Plasma (QGP), which was expected to be formed after the collision of heavy ions at a temperature of approximately 2 trillion kelvin (or equivalently an energy of 150 MeV). The QGP is the substance which existed only a few microseconds after the Big Bang. The QGP was anticipated to be weakly interacting like a gas but turned out to be strongly interacting and more like a liquid. Among its unusual properties is its extremely low viscosity [Auerbach and Schlomo (2009)], which makes the QGP the substance closest to a perfect liquid known to date. The QGP is opaque to moderate energy quarks and gluons leading to a phenomenon called jet quenching, where of a jet and its recoil jet only one is observable and the other suppressed after traversing and interacting with the QGP [Jacak and Müller (2012)]...

  1. Proton-antiproton collider physics

    SciTech Connect

    Shochet, M.J.

    1995-07-01

    The 9th {anti p}p Workshop was held in Tsukuba, Japan in October, 1993. A number of important issues remained after that meeting: Does QCD adequately describe the large cross section observed by CDF for {gamma} production below 30 GeV? Do the CDF and D0 b-production cross sections agree? Will the Tevatron live up to its billing as a world-class b-physics facility? How small will the uncertainty in the W mass be? Is there anything beyond the Minimal Standard Model? And finally, where is the top quark? Presentations at this workshop addressed all of these issues. Most of them are now resolved, but new questions have arisen. This summary focuses on the experimental results presented at the meeting by CDF and D0 physicists. Reviews of LEP and HERA results, future plans for hadron colliders and their experiments, as well as important theoretical presentations are summarized elsewhere in this volume. Section 1 reviews physics beyond the Minimal Standard Model. Issues in b and c physics are addressed in section 3. Section 4 focuses on the top quark. Electroweak physics is reviewed in section 5, followed by QCD studies in section 6. Conclusions are drawn in section 7.

  2. Beam Collimation at Hadron Colliders

    NASA Astrophysics Data System (ADS)

    Mokhov, N. V.

    2003-12-01

    Operational and accidental beam losses in hadron colliders can have a serious impact on machine and detector performance, resulting in effects ranging from minor to catastrophic. Principles and realization are described for a reliable beam collimation system required to sustain favorable background conditions in the collider detectors, provide quench stability of superconducting magnets, minimize irradiation of accelerator equipment, maintain operational reliability over the life of the machine, and reduce the impact of radiation on personnel and the environment. Based on detailed Monte-Carlo simulations, such a system has been designed and incorporated in the Tevatron collider. Its performance, comparison to measurements and possible ways to further improve the collimation efficiency are described in detail. Specifics of the collimation systems designed for the SSC, LHC, VLHC, and HERA colliders are discussed.

  3. Beam Rounders for Circular Colliders

    SciTech Connect

    A. Burov; S. Nagaitsev; Ya. Derbenev

    2001-07-01

    By means of linear optics, an arbitrary uncoupled beam can be locally transformed into a round (rotation-invariant) state and then back. This provides an efficient way to round beams in the interaction region of circular colliders.

  4. [New technology for linear colliders

    SciTech Connect

    McIntyre, P.M.

    1992-08-12

    This report discusses the following topics on research of microwave amplifiers for linear colliders: Context in current microwave technology development; gated field emission for microwave cathodes; cathode fabrication and tests; microwave cathode design using field emitters; and microwave localization.

  5. Physicists dream of supersized collider

    NASA Astrophysics Data System (ADS)

    Hao, Cindy

    2015-12-01

    Particle physicists in China are hopeful that the Chinese government will allocate 1 billion yuan (about £104m) to design what would be the world's largest particle accelerator - the Circular Electron Positron Collider (CEPC).

  6. Muon muon collider: Feasibility study

    SciTech Connect

    1996-06-18

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup {minus}2} s{sup {minus}1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice--the authors believe--to allow them to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring which has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design.

  7. Physics at Future Circular Colliders

    NASA Astrophysics Data System (ADS)

    Kotwal, Ashutosh

    2016-03-01

    The Large Hadron Collider has been a grand success with the discovery of the Higgs boson, with bright prospects for additional discoveries since the recent increase in collider energy and the anticipated large datasets. Big open questions such as the nature of dark matter, the origin of the matter-antimatter asymmetry in the Universe, and the theoretical puzzle of the finely-tuned parameters in the Higgs sector, demand new physics principles that extend the established Standard Model paradigm. Future circular colliders in a substantially larger tunnel can house both a high luminosity electron-positron collider for precision measurements of Higgs and electroweak parameters, as well as a very high energy proton-proton collider which can directly manifest particles associated with these new physics principles. We discuss the physics goals of these future circular colliders, and the prospects for elucidating fundamental new laws of nature that will significantly extend our understanding of the Universe. Detailed studies of the discovery potential in specific benchmark models will be presented, with implications for detector design.

  8. Neutrino physics at a muon collider

    SciTech Connect

    King, B.J.

    1998-02-01

    This paper gives an overview of the neutrino physics possibilities at a future muon storage ring, which can be either a muon collider ring or a ring dedicated to neutrino physics that uses muon collider technology to store large muon currents. After a general characterization of the neutrino beam and its interactions, some crude quantitative estimates are given for the physics performance of a muon ring neutrino experiment (MURINE) consisting of a high rate, high performance neutrino detector at a 250 GeV muon collider storage ring. The paper is organized as follows. The next section describes neutrino production from a muon storage rings and gives expressions for event rates in general purpose and long baseline detectors. This is followed by a section outlining a serious design constraint for muon storage rings: the need to limit the radiation levels produced by the neutrino beam. The following two sections describe a general purpose detector and the experimental reconstruction of interactions in the neutrino target then, finally, the physics capabilities of a MURINE are surveyed.

  9. Studies of E-Cloud Build up for the FNAL Main Injector and for theLHC

    SciTech Connect

    Furman, M.A.

    2006-06-14

    We present a summary of recent simulation studies of the electron-cloud (EC) build-up for the FNAL MI and for the LHC. In the first case we pay particular attention to the dependence on bunch intensity N{sub b} at injection energy assuming the nominal bunch spacing t{sub b} = 19 ns, and we focus on the dipole magnets and field-free regions. The saturated value of the average EC density shows a clear threshold in N{sub b} beyond which the beam will be approximately neutralized on average. For the case of the LHC we limit our discussion to arc dipoles at collision energy, and bunch spacings t{sub b} = 25 ns or t{sub b} = 75 ns. The main variables exercised in this study are N{sub b} and the peak value of the secondary emission yield (SEY) {delta}{sub max}. For t{sub b} = 25 ns we conclude that the EC power deposition is comfortably below the available cooling capacity of the cryogenic system if {delta}{sub max} is below {approx} 1.2 at nominal N{sub b}. For t{sub b} = 75 ns, the EC power deposition is insignificant. As a byproduct of this exercise, we reach a detailed understanding of the significant role played by the backscattered secondary electrons. This article summarizes the results, an slightly extends the discussions, presented in Refs. 1 and 2.

  10. The Structure of Jets at Hadron Colliders

    SciTech Connect

    Larkoski, Andrew James

    2012-08-01

    Particle physics seeks to understand the interactions and properties of the fundamental particles. To gain understanding, there is an interplay between theory and experiment. Models are proposed to explain how particles behave and interact. These models make precise predictions that can be tested. Experiments are built and executed to measure the properties of these particles, providing necessary tests for the theories that attempt to explain the realm of fundamental particles. However, there is also another level of interaction between theory and experiment; the development of new experiments demands the study of how particles will behave with respect to the measured observables toward the goal of understanding the details and idiosyncrasies of the measurements very well. Only once these are well-modeled and understood can one be con dent that the data that are measured is trustworthy. The modeling and interpretation of the physics of a proton collider, such as the LHC, is the main topic of this thesis.

  11. Collider study on the loop-induced dark matter mediation

    NASA Astrophysics Data System (ADS)

    Tsai, Yuhsin

    2016-06-01

    Collider experiments are one of the most promising ways to constrain Dark Matter (DM) interactions. For DM couplings involving light mediators, especially for the loop-mediated interactions, a meaningful interpretation of the results requires to go beyond effective field theory. In this note we discuss the study of the magnetic dipole interacting DM, focusing on a model with anarchic dark flavor structure. By including the momentum-dependent form factors that mediate the coupling - given by the Dark Penguin - in collider processes, we study bounds from monophoton, diphoton, and non-pointing photon searches at the LHC. We also compare our results to constraints from the direct detection experiments.

  12. R&D Toward a Neutrino Factory and Muon Collider

    SciTech Connect

    Zisman, Michael S

    2011-03-20

    Significant progress has been made in recent years in R&D towards a neutrino factory and muon collider. The U.S. Muon Accelerator Program (MAP) has been formed recently to expedite the R&D efforts. This paper will review the U.S. MAP R&D programs for a neutrino factory and muon collider. Muon ionization cooling research is the key element of the program. The first muon ionization cooling demonstration experiment, MICE (Muon Ionization Cooling Experiment), is under construction now at RAL (Rutherford Appleton Laboratory) in the UK. The current status of MICE will be described.

  13. Current experiments in elementary-particle physics - March 1983

    SciTech Connect

    Wohl, C.G.; Armstrong, F.E.; Rittenberg, A.

    1983-03-01

    Microfiche are included which contain summaries of 479 experiments in elementary particle physics. Experiments are included at the following laboratories: Brookhaven (BNL); CERN; CESR; DESY; Fermilab (FNAL); Institute for Nuclear Studies (INS); KEK; LAMPF; Serpukhov (SERP); SIN; SLAC; and TRIUMF. Also, summaries of proton decay experiments are included. A list of experiments and titles is included; and a beam-target-momentum index and a spokesperson index are given. Properties of beams at the facilities are tabulated. (WHK)

  14. High energy accelerator and colliding beam user group

    SciTech Connect

    Not Available

    1990-09-01

    This report discusses the following topics: OPAL experiment at LEP; D{phi} experiment at Fermilab; deep inelastic muon interactions at TEV II; CYGNUS experiment; final results from {nu}{sub e}{sup {minus}e} elastic scattering; physics with CLEO detector at CESR; results from JADE at PETRA; rare kaon-decay experiment at BNL; search for top quark; and super conducting super collider activities.

  15. Relativistic klystron research for linear colliders

    SciTech Connect

    Allen, M.A.; Callin, R.S.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Fowkes, W.R.; Herrmannsfeldt, W.B.; Higo, T.; Hoag, H.A.; Koontz, R.F.

    1988-09-01

    Relativistic klystrons are being developed as a power source for high gradient accelerator applications which include large linear electron-positron colliders, compact accelerators, and FEL sources. We have attained 200 MW peak power at 11.4 GHz from a relativistic klystron, and 140 MV/m longitudinal gradient in a short 11.4 GHz accelerator section. We report here on the design of our relativistic klystrons, the results of our experiments so far, and some of our plans for the near future. 5 refs., 9 figs., 1 tab.

  16. Muon collider interaction region design

    SciTech Connect

    Alexahin, Y.I.; Gianfelice-Wendt, E.; Kashikhin, V.V.; Mokhov, N.V.; Zlobin, A.V.; Alexakhin, V.Y.; /Dubna, JINR

    2010-05-01

    Design of a muon collider interaction region (IR) presents a number of challenges arising from low {beta}* < 1 cm, correspondingly large beta-function values and beam sizes at IR magnets, as well as the necessity to protect superconducting magnets and collider detectors from muon decay products. As a consequence, the designs of the IR optics, magnets and machine-detector interface are strongly interlaced and iterative. A consistent solution for the 1.5 TeV c.o.m. muon collider IR is presented. It can provide an average luminosity of 10{sup 34} cm{sup -2}s{sup -1} with an adequate protection of magnet and detector components.

  17. Luminosity determination at proton colliders

    NASA Astrophysics Data System (ADS)

    Grafström, P.; Kozanecki, W.

    2015-03-01

    Luminosity is a key parameter in any particle collider, and its precise determination has proven particularly challenging at hadron colliders. After introducing the concept of luminosity in its multiple incarnations and offering a brief survey of the pp and p p bar colliders built to date, this article outlines the various methods that have been developed for relative-luminosity monitoring, as well as the complementary approaches considered for establishing an absolute luminosity scale. This is followed by a survey, from both a historical and a technical perspective, of luminosity determination at the ISR, the S p p ¯ S, the Tevatron, RHIC and the LHC. For each of these, we first delineate the interplay between the experimental context, the specificities of the accelerator, and the precision targets suggested by the physics program. We then detail how the different methods were applied to specific experimental environments and how successfully they meet the precision goals.

  18. Beam-Based Alignment of the NuMI Target Station Components at FNAL

    SciTech Connect

    Zwaska, R.; Bishai, M.; Childress, S.; Drake, G.; Escobar, C.; Gouffon, P.; Harris, D.A.; Hylen, J.; Indurthy, D.; Koizumi, G.; Kopp, S.; /Argonne /Brookhaven /Frascati /Sao Paulo U. /Campinas State U. /Texas U.

    2006-09-01

    The Neutrinos at the Main Injector (NuMI) facility is a conventional horn-focused neutrino beam which produces muon neutrinos from a beam of mesons directed into a long evacuated decay volume. The relative alignment of the primary proton beam, target, and focusing horns affects the neutrino energy spectrum delivered to experiments. This paper describes a check of the alignment of these components using the proton beam.

  19. The NuMI Beam at FNAL and its Use for Neutrino Cross Section Measurements

    SciTech Connect

    Kopp, Sacha E.

    2007-12-21

    The Neutrinos at the Main Injector (NuMI) facility at Fermilab began operations in late 2004. NuMI will deliver an intense {nu}{sub {mu}} beam of variable energy (2-20 GeV). Several aspects of the design and results from runs of the MINOS experiment are reviewed. I also discuss technique to measure directly the neutrino flux using a muon flux system at the end of the NuMI line.

  20. The dark penguin shines light at colliders

    NASA Astrophysics Data System (ADS)

    Primulando, Reinard; Salvioni, Ennio; Tsai, Yuhsin

    2015-07-01

    Collider experiments are one of the most promising ways to constrain Dark Matter (DM) interactions. For several types of DM-Standard Model couplings, a meaningful interpretation of the results requires to go beyond effective field theory, considering simplified models with light mediators. This is especially important in the case of loop-mediated interactions. In this paper we perform the first simplified model study of the magnetic dipole interacting DM, by including the one-loop momentum-dependent form factors that mediate the coupling — given by the Dark Penguin — in collider processes. We compute bounds from the monojet, monophoton, and diphoton searches at the 8 and 14 TeV LHC, and compare the results to those of direct and indirect detection experiments. Future searches at the 100 TeV hadron collider and at the ILC are also addressed. We find that the optimal search strategy requires loose cuts on the missing transverse energy, to capture the enhancement of the form factors near the threshold for on-shell production of the mediators. We consider both minimal models and models where an additional state beyond the DM is accessible. In the latter case, under the assumption of anarchic flavor structure in the dark sector, the LHC monophoton and diphoton searches will be able to set much stronger bounds than in the minimal scenario. A determination of the mass of the heavier dark fermion might be feasible using the M T2 variable. In addition, if the Dark Penguin flavor structure is almost aligned with that of the DM mass, a displaced signal from the decay of the heavier dark fermion into the DM and photon can be observed. This allows us to set constraints on the mixings and couplings of the model from an existing search for non-pointing photons.

  1. Study of requirements and performances of the electromagnetic calorimeter for the Mu2e experiment at Fermilab

    SciTech Connect

    Soleti, S.

    2015-06-15

    In this thesis we discuss the simulation and tests carried out for the optimization and design of the electromagnetic calorimeter for the Mu2e (Muon to electron conversion) experiment, which is a proposed experiment part of the Muon Campus hosted at Fermi National Accelerator Laboratory (FNAL) in Batavia, United States.

  2. Measurement of the radiation field surrounding the Collider Detector at Fermilab

    SciTech Connect

    K. Kordas et al.

    2004-01-28

    We present here the first direct and detailed measurements of the spatial distribution of the ionizing radiation surrounding a hadron collider experiment. Using data from two different exposures we measure the effect of additional shielding on the radiation field around the Collider Detector at Fermilab (CDF). Employing a simple model we parameterize the ionizing radiation field surrounding the detector.

  3. Muon Muon Collider: Feasibility Study

    SciTech Connect

    Gallardo, J.C.; Palmer, R.B.; Tollestrup, A.V.; Sessler, A.M.; Skrinsky, A.N.; Ankenbrandt, C.; Geer, S.; Griffin, J.; Johnstone, C.; Lebrun, P.; McInturff, A.; Mills, Frederick E.; Mokhov, N.; Moretti, A.; Neuffer, D.; Ng, K.Y.; Noble, R.; Novitski, I.; Popovic, M.; Qian, C.; Van Ginneken, A. /Fermilab /Brookhaven /Wisconsin U., Madison /Tel Aviv U. /Indiana U. /UCLA /LBL, Berkeley /SLAC /Argonne /Sobolev IM, Novosibirsk /UC, Davis /Munich, Tech. U. /Virginia U. /KEK, Tsukuba /DESY /Novosibirsk, IYF /Jefferson Lab /Mississippi U. /SUNY, Stony Brook /MIT /Columbia U. /Fairfield U. /UC, Berkeley

    2012-04-05

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle

  4. Overview and performance of the FNAL KTeV DAQ system

    SciTech Connect

    Nakaya, T.; O`Dell, V.; Hazumi, M.; Yamanaka, T.

    1995-11-01

    KTeV is a new fixed target experiment at Fermilab designed to study CP violation in the neutral kaon system. The KTeV Data Acquisition System (DAQ) is out of the highest performance DAQ`s in the field of high energy physics. The sustained data throughput of the KTeV DAQ reaches 160 Mbytes/sec, and the available online level 3 processing power is 3600 Mips. In order to handle such high data throughput, the KTeV DAQ is designed around a memory matrix core where the data flow is divided and parallelized. In this paper, we present the architecture and test results of the KTeV DAQ system.

  5. Muon Colliders: The Next Frontier

    ScienceCinema

    Tourun, Yagmur [Illinois Institute of Technology, Chicago, Illinois, United States

    2010-01-08

    Muon Colliders provide a path to the energy frontier in particle physics but have been regarded to be "at least 20 years away" for 20 years. I will review recent progress in design studies and hardware R&D and show that a Muon Collider can be established as a real option for the post-LHC era if the current vigorous R&D effort revitalized by the Muon Collider Task Force at Fermilab can be supported to its conclusion. All critical technologies are being addressed and no show-stoppers have emerged. Detector backgrounds have been studied in detail and appear to be manageable and the physics can be done with existing detector technology. A muon facility can be built through a staged scenario starting from a low-energy muon source with unprecedented intensity for exquisite reach for rare processes, followed by a Neutrino Factory with ultrapure neutrino beams with unparalleled sensitivity for disentangling neutrino mixing, leading to an energy frontier Muon Collider with excellent energy resolution.

  6. Muon Colliders: The Next Frontier

    SciTech Connect

    Tourun, Yagmur

    2009-07-29

    Muon Colliders provide a path to the energy frontier in particle physics but have been regarded to be 'at least 20 years away' for 20 years. I will review recent progress in design studies and hardware R&D and show that a Muon Collider can be established as a real option for the post-LHC era if the current vigorous R&D effort revitalized by the Muon Collider Task Force at Fermilab can be supported to its conclusion. All critical technologies are being addressed and no show-stoppers have emerged. Detector backgrounds have been studied in detail and appear to be manageable and the physics can be done with existing detector technology. A muon facility can be built through a staged scenario starting from a low-energy muon source with unprecedented intensity for exquisite reach for rare processes, followed by a Neutrino Factory with ultrapure neutrino beams with unparalleled sensitivity for disentangling neutrino mixing, leading to an energy frontier Muon Collider with excellent energy resolution.

  7. Muon Colliders: The Next Frontier

    SciTech Connect

    Tourun, Yagmur

    2009-07-29

    Muon Colliders provide a path to the energy frontier in particle physics but have been regarded to be "at least 20 years away" for 20 years. I will review recent progress in design studies and hardware R&D and show that a Muon Collider can be established as a real option for the post-LHC era if the current vigorous R&D effort revitalized by the Muon Collider Task Force at Fermilab can be supported to its conclusion. All critical technologies are being addressed and no show-stoppers have emerged. Detector backgrounds have been studied in detail and appear to be manageable and the physics can be done with existing detector technology. A muon facility can be built through a staged scenario starting from a low-energy muon source with unprecedented intensity for exquisite reach for rare processes, followed by a Neutrino Factory with ultrapure neutrino beams with unparalleled sensitivity for disentangling neutrino mixing, leading to an energy frontier Muon Collider with excellent energy resolution.

  8. The very large hadron collider

    SciTech Connect

    1998-09-01

    This paper reviews the purposes to be served by a very large hadron collider and the organization and coordination of efforts to bring it about. There is some discussion of magnet requirements and R&D and the suitability of the Fermilab site.

  9. Japanese lab spells out collider needs

    NASA Astrophysics Data System (ADS)

    Banks, Michael

    2016-02-01

    Japan's High Energy Accelerator Research Organization (KEK) last month issued a plan for the International Linear Collider (ILC) that calls on Japan to ramp up its expertise as it prepares to host the world's next-generation particle collider.

  10. Physics at high energy photon photon colliders

    SciTech Connect

    Chanowitz, M.S.

    1994-06-01

    I review the physic prospects for high energy photon photon colliders, emphasizing results presented at the LBL Gamma Gamma Collider Workshop. Advantages and difficulties are reported for studies of QCD, the electroweak gauge sector, supersymmetry, and electroweak symmetry breaking.

  11. Searches for new gauge bosons at future colliders

    SciTech Connect

    Rizzo, T.G.

    1996-09-01

    The search reaches for new gauge bosons at future hadron and lepton colliders are summarized for a variety of extended gauge models. Experiments at these energies will vastly improve over present limits and will easily discover a Z` and/or W` in the multi-TeV range.

  12. Latest results of searches for new physics in the D0 experiment

    SciTech Connect

    Popov, A. V.

    2013-09-15

    Results on searches for particles and phenomena beyond the Standard Model (new-physics effects) in the D0 experiment at the Tevatron accelerator (FNAL, USA) are examined. These results were obtained on the basis of a statistical sample corresponding to an integrated luminosity of 5 to 7 fb{sup -1} and were published in 2010 and 2011.

  13. Work at FNAL to achieve long electron drift lifetime in liquid argon

    SciTech Connect

    Finley, D.; Jaskierny, W.; Kendziora, C.; Krider, J.; Pordes, S.; Rapidis, P.A.; Tope, T.; /Fermilab

    2006-10-01

    This note records some of the work done between July 2005 and July 2006 to achieve long (many milliseconds) electron drift lifetimes in liquid argon at Fermilab. The work is part of a process to develop some experience at Fermilab with the technology required to construct a large liquid argon TPC. This technology has been largely developed by the ICARUS collaboration in Europe and this process can be seen as technology transfer. The capability to produce liquid argon in which electrons have drift lifetimes of several milliseconds is crucial to a successful device. Liquid argon calorimeters have been successfully operated at Fermilab; their electro-negative contaminants are at the level of 10{sup -7} while the TPC we are considering requires a contamination level at the level of 10{sup -11}, tens of parts per trillion (ppt). As well as demonstrating the ability to produce liquid argon at this level of purity, the work is part of a program to test the effect on the electron drift time of candidate materials for the construction of a TPC in liquid argon.

  14. From Neutrino Factory to Muon Collider

    SciTech Connect

    Geer, S.; /Fermilab

    2010-01-01

    Both Muon Colliders and Neutrino Factories require a muon source capable of producing and capturing {Omicron}(10{sup 21}) muons/year. This paper reviews the similarities and differences between Neutrino Factory and Muon Collider accelerator complexes, the ongoing R&D needed for a Muon Collider that goes beyond Neutrino Factory R&D, and some thoughts about how a Neutrino Factory on the CERN site might eventually be upgraded to a Muon Collider.

  15. MIGHTY MURINES: NEUTRINO PHYSICS AT VERY HIGH ENERGY MUON COLLIDERS

    SciTech Connect

    KING,B.J.

    2000-05-05

    An overview is given of the potential for neutrino physics studies through parasitic use of the intense high energy neutrino beams that would be produced at future many-TeV muon colliders. Neutrino experiments clearly cannot compete with the collider physics. Except at the very highest energy muon colliders, the main thrust of the neutrino physics program would be to improve on the measurements from preceding neutrino experiments at lower energy muon colliders, particularly in the fields of B physics, quark mixing and CP violation. Muon colliders at the 10 TeV energy scale might already produce of order 10{sup 8} B hadrons per year in a favorable and unique enough experimental environment to have some analytical capabilities beyond any of the currently operating or proposed B factories. The most important of the quark mixing measurements at these energies might well be the improved measurements of the important CKM matrix elements {vert_bar}V{sub ub}{vert_bar} and {vert_bar}V{sub cb}{vert_bar} and, possibly, the first measurements of {vert_bar}V{sub td}{vert_bar} in the process of flavor changing neutral current interactions involving a top quark loop. Muon colliders at the highest center-of-mass energies that have been conjectured, 100--1,000 TeV, would produce neutrino beams for neutrino-nucleon interaction experiments with maximum center-of-mass energies from 300--1,000 GeV. Such energies are close to, or beyond, the discovery reach of all colliders before the turn-on of the LHC. In particular, they are comparable to the 314 GeV center-of-mass energy for electron-proton scattering at the currently operating HERA collider and so HERA provides a convenient benchmark for the physics potential. It is shown that these ultimate terrestrial neutrino experiments, should they eventually come to pass, would have several orders of magnitude more luminosity than HERA. This would potentially open up the possibility for high statistics studies of any exotic particles, such as

  16. Collider Detector at Fermilab (CDF): Data from B Hadrons Research

    DOE Data Explorer

    The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group is organized into six working groups, each with a specific focus. The Bottom group studies the production and decay of B hadrons. Their public web page makes data and numerous figures available from both CDF Runs I and II.

  17. Experimental demonstration of colliding beam lifetime improvement by electron lenses

    SciTech Connect

    Shiltsev, Vladimir; Alexahin, Yuri; Kamerdzhiev, Vsevolod; Kuznetsov, Gennady; Zhang, Xiao-Long; Bishofberger, Kip; /Los Alamos

    2007-10-01

    We report successful application of space-charge forces of a low-energy electron beam for improvement of particle lifetime determined by beam-beam interaction in high-energy collider. In our experiments, an electron lens, a novel instrument developed for the beam-beam compensation, was set on a 980-GeV proton bunch in the Tevatron proton-antiproton collider. The proton bunch losses due to its interaction with antiproton beam were reduced by a factor of 2 when the electron lens was operating. We describe the principle of electron lens operation and present experimental results.

  18. Searches for scalar and vector leptoquarks at future hadron colliders

    SciTech Connect

    Rizzo, T.G.

    1996-09-01

    The search reaches for both scalar(S) and vector(V) leptoquarks at future hadron colliders are summarized. In particular the authors evaluate the production cross sections of both leptoquark types at TeV33 and LHC as well as the proposed 60 and 200 TeV colliders through both quark-antiquark annihilation and gluon-gluon fusion: q{anti q},gg {r_arrow} SS,VV. Experiments at these machines should easily discover such particles if their masses are not in excess of the few TeV range.

  19. When shock waves collide

    DOE PAGESBeta

    Martinez, D.; Hartigan, P.; Frank, A.; Hansen, E.; Yirak, K.; Liao, A. S.; Graham, P.; Foster, J.; Wilde, B.; Blue, B.; et al

    2016-06-01

    Supersonic outflows from objects as varied as stellar jets, massive stars, and novae often exhibit multiple shock waves that overlap one another. When the intersection angle between two shock waves exceeds a critical value, the system reconfigures its geometry to create a normal shock known as a Mach stem where the shocks meet. Mach stems are important for interpreting emission-line images of shocked gas because a normal shock produces higher postshock temperatures, and therefore a higher-excitation spectrum than does an oblique shock. In this paper, we summarize the results of a series of numerical simulations and laboratory experiments designed tomore » quantify how Mach stems behave in supersonic plasmas that are the norm in astrophysical flows. The experiments test analytical predictions for critical angles where Mach stems should form, and quantify how Mach stems grow and decay as intersection angles between the incident shock and a surface change. While small Mach stems are destroyed by surface irregularities and subcritical angles, larger ones persist in these situations and can regrow if the intersection angle changes to become more favorable. Furthermore, the experimental and numerical results show that although Mach stems occur only over a limited range of intersection angles and size scales, within these ranges they are relatively robust, and hence are a viable explanation for variable bright knots observed in Hubble Space Telescope images at the intersections of some bow shocks in stellar jets.« less

  20. When Shock Waves Collide

    NASA Astrophysics Data System (ADS)

    Hartigan, P.; Foster, J.; Frank, A.; Hansen, E.; Yirak, K.; Liao, A. S.; Graham, P.; Wilde, B.; Blue, B.; Martinez, D.; Rosen, P.; Farley, D.; Paguio, R.

    2016-06-01

    Supersonic outflows from objects as varied as stellar jets, massive stars, and novae often exhibit multiple shock waves that overlap one another. When the intersection angle between two shock waves exceeds a critical value, the system reconfigures its geometry to create a normal shock known as a Mach stem where the shocks meet. Mach stems are important for interpreting emission-line images of shocked gas because a normal shock produces higher postshock temperatures, and therefore a higher-excitation spectrum than does an oblique shock. In this paper, we summarize the results of a series of numerical simulations and laboratory experiments designed to quantify how Mach stems behave in supersonic plasmas that are the norm in astrophysical flows. The experiments test analytical predictions for critical angles where Mach stems should form, and quantify how Mach stems grow and decay as intersection angles between the incident shock and a surface change. While small Mach stems are destroyed by surface irregularities and subcritical angles, larger ones persist in these situations and can regrow if the intersection angle changes to become more favorable. The experimental and numerical results show that although Mach stems occur only over a limited range of intersection angles and size scales, within these ranges they are relatively robust, and hence are a viable explanation for variable bright knots observed in Hubble Space Telescope images at the intersections of some bow shocks in stellar jets.

  1. (Calorimeter based detectors for high energy hadron colliders). [State Univ. of New York

    SciTech Connect

    Not Available

    1992-08-04

    This document provides a progress report on research that has been conducted under DOE Grant DEFG0292ER40697 for the past year, and describes proposed work for the second year of this 8 year grant starting November 15, 1992. Personnel supported by the contract include 4 faculty, 1 research faculty, 4 postdocs, and 9 graduate students. The work under this grant has in the past been directed in two complementary directions -- DO at Fermilab, and the second SSC detector GEM. A major effort has been towards the construction and commissioning of the new Fermilab Collider detector DO, including design, construction, testing, the commissioning of the central tracking and the central calorimeters. The first DO run is now underway, with data taking and analysis of the first events. Trigger algorithms, data acquisition, calibration of tracking and calorimetry, data scanning and analysis, and planning for future upgrades of the DO detector with the advent of the FNAL Main Injector are all involved. The other effort supported by this grant has been towards the design of GEM, a large and general-purpose SSC detector with special emphasis on accurate muon measurement over a large solid angle. This effort will culminate this year in the presentation to the SSC laboratory of the GEM Technical Design Report. Contributions are being made to the detector design, coordination, and physics simulation studies with special emphasis on muon final states. Collaboration with the RD5 group at CERN to study muon punch through and to test cathode strip chamber prototypes was begun.

  2. Single event effects and their mitigation for the Collider Detector at Fermilab

    SciTech Connect

    Tesarek, Richard J.; D'Auria, Saverio; Dong, Peter; Hocker, Andy; Kordas, Kostas; McGimpsey, Susan; Nicolas, Ludovic; Wallny, Rainer; Schmitt, Wayne; Worm, Steven; /Fermilab /Toronto U. /Glasgow U. /Rutherford /UCLA

    2005-11-01

    We present an overview of radiation induced failures and operational experiences from the Collider Detector at Fermilab (CDF). In our summary, we examine single event effects (SEE) in electronics located in and around the detector. We present results of experiments to identify the sources and composition of the radiation and steps to reduce the rate of SEEs in our electronics. Our studies have led to a better, more complete understanding of the radiation environment in a modern hadron collider experiment.

  3. Advances in beam physics and technology: Colliders of the future

    NASA Astrophysics Data System (ADS)

    Chattopadhyay, Swapan

    1996-02-01

    Beams may be viewed as directed and focussed flow of energy and information, carried by particles and electromagnetic radiation fields (i.e. photons). Often, they are brought into interaction with each other (e.g. in high energy colliders) or with other forms of matter (e.g. in fixed target physics, synchrotron radiation sciences, neutron scattering experiments, laser chemistry and physics, medical therapy, etc.). The whole art and science of beams revolve around the fundamental quest for, and ultimate implementation of, mechanisms of production, storage, control and observation of beams—always directed towards studies of the basic structures and processes of the natural world and various practical applications. Tremendous progress has been made in all aspects of beam physics and technology in the last decades—nonlinear dynamics, superconducting magnets and radio frequency cavities, beam instrumentation and control, novel concepts and collider paradigms, to name a few. We will illustrate this progress via a few examples and remark on the emergence of new collider scenarios where some of these progress might come to use—the Gamma-Gamma Collider, the Muon Collider, laser acceleration, etc. We will close with an outline of future opportunities and outlook.

  4. Vacuum technology issues for the SSC (Superconducting Super Collider)

    SciTech Connect

    Joestlein, H.

    1989-10-23

    The Superconducting Super Collider, to be built in Texas, will provide an energy of 40 TeV from colliding proton beams. This energy is twenty times higher than currently available from the only other cryogenic collider, the Fermilab Tevatron, and will allow experiments that can lead to a better understanding of the fundamental properties of matter. The energy scale and the size of the new machine pose intriguing challenges and opportunities for the its vacuum systems. The discussion will include the effects of synchrotron radiation on cryogenic beam tubes, cold adsorption pumps for hydrogen, methods of leak checking large cryogenic systems, the development of cold beam valves, and radiation damage to components, especially electronics. 9 figs., 1 tab.

  5. Colliding Decimeter Dust

    NASA Astrophysics Data System (ADS)

    Deckers, J.; Teiser, J.

    2013-06-01

    Collisional evolution is a key process in planetesimal formation and decimeter bodies play a key role in the different models. However, the outcome of collisions between two dusty decimeter bodies has never been studied experimentally. Therefore, we carried out microgravity collision experiments in the Bremen drop tower. The agglomerates consist of quartz with irregularly shaped micrometer-sized grains and the mean volume filling factor is 0.437 ± 0.004. The aggregates are cylindrical with 12 cm in height and 12 cm in diameter, and typical masses are 1.5 kg. These are the largest and most massive dust aggregates studied in collisions to date. We observed rebound and fragmentation but no sticking in the velocity range between 0.8 and 25.7 cm s-1. The critical fragmentation velocity for split up of an aggregate is 16.2 ± 0.4 cm s-1. At lower velocities the aggregates bounce off each other. In this velocity range, the coefficient of restitution decreases with increasing collision velocity from 0.8 to 0.3. While the aggregates are very weak, the critical specific kinetic energy for fragmentation Q μ = 1 is a factor of six larger than expected. Collisions of large bodies in protoplanetary disks are supposed to be much faster and the generation of smaller fragments is likely. In planetary rings, collision velocities are of the order of a few cm s-1 and are thereby in the same range investigated in these experiments. The coefficient of restitution of dust agglomerates and regolith-covered ice particles, which are common in planetary rings, are similar.

  6. Future Electron-Hadron Colliders

    SciTech Connect

    Litvinenko, V.

    2010-05-23

    Outstanding research potential of electron-hadron colliders (EHC) was clearly demonstrated by first - and the only - electron-proton collider HERA (DESY, Germany). Physics data from HERA revealed new previously unknown facets of Quantum Chromo-Dynamics (QCD). EHC is an ultimate microscope probing QCD in its natural environment, i.e. inside the hadrons. In contrast with hadrons, electrons are elementary particles with known initial state. Hence, scattering electrons from hadrons provides a clearest pass to their secrets. It turns EHC into an ultimate machine for high precision QCD studies and opens access to rich physics with a great discovery potential: solving proton spin puzzle, observing gluon saturation or physics beyond standard model. Access to this physics requires high-energy high-luminosity EHCs and a wide reach in the center-of-mass (CM) energies. This paper gives a brief overview of four proposed electron-hadron colliders: ENC at GSI (Darmstadt, Germany), ELIC/MEIC at TJNAF (Newport News, VA, USA), eRHIC at BNL (Upton, NY, USA) and LHeC at CERN (Geneva, Switzerland). Future electron-hadron colliders promise to deliver very rich physics not only in the quantity but also in the precision. They are aiming at very high luminosity two-to-four orders of magnitude beyond the luminosity demonstrated by the very successful HERA. While ENC and LHeC are on opposite side of the energy spectrum, eRHIC and ELIC are competing for becoming an electron-ion collider (EIC) in the U.S. Administrations of BNL and Jlab, in concert with US DoE office of Nuclear Physics, work on the strategy for down-selecting between eRHIC and ELIC. The ENC, EIC and LHeC QCD physics programs to a large degree are complimentary to each other and to the LHC physics. In last decade, an Electron Ion Collider (EIC) collaboration held about 25 collaboration meetings to develop physics program for EIC with CM energy {approx}100 GeV. One of these meetings was held at GSI, where ENC topic was in the

  7. Dark Matter: Collider vs. direct searches

    NASA Astrophysics Data System (ADS)

    Jacques, T.

    2016-07-01

    Effective Field Theories (EFTs) are a useful tool across a wide range of DM searches, including LHC searches and direct detection. Given the current lack of indications about the nature of the DM particle and its interactions, a model independent interpretation of the collider bounds appears mandatory, especially in complementarity with the reinterpretation of the exclusion limits within a choice of simplified models, which cannot exhaust the set of possible completions of an effective Lagrangian. However EFTs must be used with caution at LHC energies, where the energy scale of the interaction is at a scale where the EFT approximation can no longer be assumed to be valid. Here we introduce some tools that allow the validity of the EFT approximation to be quantified, and provide case studies for two operators. We also show a technique that allows EFT constraints from collider searches to be made substantially more robust, even at large center-of-mass energies. This allows EFT constraints from different classes of experiment to be compared in a much more robust manner.

  8. Advances in Beam Cooling for Muon Colliders

    SciTech Connect

    R.P. Johnson, Y.S. Derbenev

    2006-09-01

    A six-dimensional (6D) ionization cooling channel based on helical magnets surrounding RF cavities filled with dense hydrogen gas is the basis for the latest plans for muon colliders. This helical cooling channel (HCC) has solenoidal, helical dipole, and helical quadrupole magnetic fields, where emittance exchange is achieved by using a continuous homogeneous absorber. Momentum-dependent path length differences in the dense hydrogen energy absorber provide the required correlation between momentum and ionization loss to accomplish longitudinal cooling. Recent studies of an 800 MHz RF cavity pressurized with hydrogen, as would be used in this application, show that the maximum gradient is not limited by a large external magnetic field, unlike vacuum cavities. Two new cooling ideas, Parametric-resonance Ionization Cooling and Reverse Emittance Exchange, will be employed to further reduce transverse emittances to a few mm-mr, which allows high luminosity with fewer muons than previously imagined. We describe these new ideas as well as a new precooling idea based on a HCC with z dependent fields that is being developed for an exceptional 6D cooling demonstration experiment. The status of the designs, simulations, and tests of the cooling components for a high luminosity, low emittance muon collider will be reviewed.

  9. Overview of linear collider designs

    SciTech Connect

    Siemann, R.H.

    1993-04-01

    Linear collider design and development have become focused on a center-of-mass energy E{sub CM} = 0.5 TeV and a luminosity L {approximately} 5 {times} 10{sup 33} cm{sup {minus}2}sec{sup {minus}1}. There are diverse approaches to meeting these general objectives. The diversity arises from different judgements about the ease of developing new and improving existing technology, costs, extension to higher energies, experimental backgrounds and center-of-mass energy spectrum, and tolerances and beam power. The parameters of possible colliders are given in this paper. This report will focus on some of the common themes of these designs and the different between them.

  10. Crab Cavities for Linear Colliders

    SciTech Connect

    Burt, G.; Ambattu, P.; Carter, R.; Dexter, A.; Tahir, I.; Beard, C.; Dykes, M.; Goudket, P.; Kalinin, A.; Ma, L.; McIntosh, P.; Shulte, D.; Jones, Roger M.; Bellantoni, L.; Chase, B.; Church, M.; Khabouline, T.; Latina, A.; Adolphsen, C.; Li, Z.; Seryi, Andrei; /SLAC

    2011-11-08

    Crab cavities have been proposed for a wide number of accelerators and interest in crab cavities has recently increased after the successful operation of a pair of crab cavities in KEK-B. In particular crab cavities are required for both the ILC and CLIC linear colliders for bunch alignment. Consideration of bunch structure and size constraints favour a 3.9 GHz superconducting, multi-cell cavity as the solution for ILC, whilst bunch structure and beam-loading considerations suggest an X-band copper travelling wave structure for CLIC. These two cavity solutions are very different in design but share complex design issues. Phase stabilisation, beam loading, wakefields and mode damping are fundamental issues for these crab cavities. Requirements and potential design solutions will be discussed for both colliders.

  11. Reviews Exhibitions: Collider: Step inside the World's Greatest Experiment Equipment: Hero Steam Turbine Classroom Video: Most of Our Universe is Missing Book: Serving the Reich Book: Breakthrough to CLIL for Physics Book: The Good Research Guide Apps: Popplet Web Watch Apps

    NASA Astrophysics Data System (ADS)

    2014-03-01

    WE RECOMMEND Collider: step inside the world's greatest experiment A great exhibition at the Science Museum in London Hero Steam Turbine Superb engine model gets up to 2500 rpm Most of Our Universe is Missing BBC video explores the dark truth Serving the Reich Science and morality in Nazi Germany The Good Research Guide A non-specialist book for teachers starting out in education research WORTH A LOOK Breakthrough to CLIL for Physics A book based on a physics curriculum for non-English students WEB WATCH Electric cycles online: patterns of use APPS The virtual laboratory advances personal skills

  12. Dark matter searches at the large hadron collider

    NASA Astrophysics Data System (ADS)

    Hoh, S. Y.; Komaragiri, J. R.; Wan Abdullah, W. A. T.

    2016-01-01

    Dark Matter is a hypothetical particle proposed to explain the missing matter expected from the cosmological observation. The motivation of Dark Matter is overwhelming however as it is mainly deduced from its gravitational interaction, for it does little to pinpoint what Dark Matter really is. In WIMPs Miracle, weakly interactive massive particle being the Dark Matter candidate is correctly producing the current thermal relic density at weak scale, implying the possibility of producing and detecting it in Large Hadron Collider. Assuming WIMPs being the maverick particle within collider, it is expected to be pair produced in association with a Standard Model particle. The presence of the WIMPs pair is inferred from the Missing Transverse Energy (MET) which is the vector sum of the imbalance in the transverse momentum plane recoils a Standard Model Particle. The collider is able to produce light mass Dark Matter which the traditional detection fail to detect due to the small momentum transfer involved in the interaction; on the other hand, the traditional detection is robust in detecting a higher Dark matter masses but the collider is suffered from the parton distribution function suppression. Topologically the processes are similar to the scattering processes in the direct detection thus complementary to the traditional Dark Matter detection. The collider searches are strongly motivated as the results are usually translated to the annihilation and scattering rates at more traditional Dark Matter-oriented experiments, thus a concordance approach is adapted. An overview of Dark Matter searches at the Large Hadron Collider will be covered in this paper.

  13. Collider searches for nonperturbative low-scale gravity states

    NASA Astrophysics Data System (ADS)

    Gingrich, Douglas M.

    2015-12-01

    The possibility of producing nonperturbative low-scale gravity states in collider experiments was first discussed in about 1998. The ATLAS and CMS experiments have searched for nonperturbative low-scale gravity states using the Large Hadron Collider with a proton-proton center-of-mass energy of 8 TeV. These experiments have now seriously confronted the possibility of producing nonperturbative low-scale gravity states which were proposed over 17 years ago. I will summarize the results of the searches, give a personal view of what they mean, and make some predictions for 13 TeV center-of-mass energy. I will also discuss early ATLAS 13 TeV center-of-mass energy results.

  14. LHC: The Large Hadron Collider

    SciTech Connect

    Lincoln, Don

    2015-03-04

    The Large Hadron Collider (or LHC) is the world’s most powerful particle accelerator. In 2012, scientists used data taken by it to discover the Higgs boson, before pausing operations for upgrades and improvements. In the spring of 2015, the LHC will return to operations with 163% the energy it had before and with three times as many collisions per second. It’s essentially a new and improved version of itself. In this video, Fermilab’s Dr. Don Lincoln explains both some of the absolutely amazing scientific and engineering properties of this modern scientific wonder.

  15. Colliding-beam-accelerator lattice

    SciTech Connect

    Claus, J.; Cornacchia, M.; Courant, E.D.; Parzen, G.

    1983-01-01

    We describe the lattice of the Colliding Beam Accelerator, a 400 x 400 GeV pp facility proposed for construction at Brookhaven National Laboratory. The structure adopted is very versatile, in part in consequence of its desirable behavior as function of momentum deviation and as function of the betatron tunes. Each of the six insertions can be arranged to meet specific requirements at the crossing points as illustrated by a discussion of the tuneable low-beta insertions. The luminosity in these low-beta insertions (2 x 10/sup 33/ cm/sup -2/ sec/sup -1/) would be an order of magnitude larger than the standard insertions.

  16. Tevatron instrumentation: boosting collider performance

    SciTech Connect

    Shiltsev, Vladimir; Jansson, Andreas; Moore, Ronald; /Fermilab

    2006-05-01

    The Tevatron in Collider Run II (2001-present) is operating with six times more bunches, many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for the next big machines--LHC and ILC.

  17. Detector Background at Muon Colliders

    SciTech Connect

    Mokhov, N.V.; Striganov, S.I.; /Fermilab

    2011-09-01

    Physics goals of a Muon Collider (MC) can only be reached with appropriate design of the ring, interaction region (IR), high-field superconducting magnets, machine-detector interface (MDI) and detector. Results of the most recent realistic simulation studies are presented for a 1.5-TeV MC. It is shown that appropriately designed IR and MDI with sophisticated shielding in the detector have a potential to substantially suppress the background rates in the MC detector. The main characteristics of backgrounds are studied.

  18. Colliding with a crunching bubble

    SciTech Connect

    Freivogel, Ben; Freivogel, Ben; Horowitz, Gary T.; Shenker, Stephen

    2007-03-26

    In the context of eternal inflation we discuss the fate of Lambda = 0 bubbles when they collide with Lambda< 0 crunching bubbles. When the Lambda = 0 bubble is supersymmetric, it is not completely destroyed by collisions. If the domain wall separating the bubbles has higher tension than the BPS bound, it is expelled from the Lambda = 0 bubble and does not alter its long time behavior. If the domain wall saturates the BPS bound, then it stays inside the Lambda = 0 bubble and removes a finite fraction of future infinity. In this case, the crunch singularity is hidden behind the horizon of a stable hyperbolic black hole.

  19. Estimates of Fermilab Tevatron collider performance

    SciTech Connect

    Dugan, G.

    1991-09-01

    This paper describes a model which has been used to estimate the average luminosity performance of the Tevatron collider. In the model, the average luminosity is related quantitatively to various performance parameters of the Fermilab Tevatron collider complex. The model is useful in allowing estimates to be developed for the improvements in average collider luminosity to be expected from changes in the fundamental performance parameters as a result of upgrades to various parts of the accelerator complex.

  20. International Workshop on Linear Colliders 2010

    ScienceCinema

    None

    2011-10-06

    IWLC2010 International Workshop on Linear Colliders 2010ECFA-CLIC-ILC joint meeting: Monday 18 October - Friday 22 October 2010Venue: CERN and CICG (International Conference Centre Geneva, Switzerland) This year, the International Workshop on Linear Colliders organized by the European Committee for Future Accelerators (ECFA) will study the physics, detectors and accelerator complex of a linear collider covering both CLIC and ILC options.Contact Workshop Secretariat  IWLC2010 is hosted by CERN

  1. 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

  2. FUTURE LEPTON COLLIDERS AND LASER ACCELERATION

    SciTech Connect

    PARSA,Z.

    2000-05-30

    Future high energy colliders along with their physics potential, and relationship to new laser technology are discussed. Experimental approaches and requirements for New Physics exploration are also described.

  3. Next-Generation Linear Collider Final Focus System Stability Tolerances

    SciTech Connect

    Roy, G.; Irwin, J.; /SLAC

    2007-04-25

    The design of final focus systems for the next generation of linear colliders has evolved largely from the experience gained with the design and operation of the Stanford Linear Collider (SLC) and with the design of the Final Focus Test Beam (FFTB). We will compare the tolerances for two typical designs for a next-generation linear collider final focus system. The chromaticity generated by strong focusing systems, like the final quadrupole doublet before the interaction point of a linear collider, can be canceled by the introduction of sextupoles in a dispersive region. These sextupoles must be inserted in pairs separated by a -I transformation (Chromatic Correction Section) in order to cancel the strong geometric aberrations generated by sextupoles. Designs proposed for both the JLC or NLC final focus systems have two separate chromatic correction sections, one for each transverse plane separated by a ''{beta}-exchanger'' to manipulate the {beta}-function between the two CCS. The introduction of sextupoles and bending magnets gives rise to higher order aberrations (long sextupole and chrome-geometries) and radiation induced aberrations (chromaticity unbalance and ''Oide effect'') and one must optimize the lattice accordingly.

  4. Charge resolved electrostatic diagnostic of colliding copper laser plasma plumes

    SciTech Connect

    Yeates, P.; Fallon, C.; Kennedy, E. T.; Costello, J. T.

    2011-10-15

    The collision of two laser generated plasma plumes can result, under appropriate conditions, in the formation of a ''stagnation layer.'' The processes underlying this phenomenon are complex and time dependent. The majority of experiments over the last few decades have focused upon spectroscopic diagnostic of colliding plasmas. We have performed electrostatic diagnosis of multiply charged copper ions (Cu{sup +} to Cu{sup 5+}) generated via Q-switched pulsed laser ({lambda} = 1.06 {mu}m, {tau} = 6 ns, and E{sub L} = 52-525 mJ) generation of copper plasma plumes from a planar target. Time dependent current traces, charge yields, and kinetic energy (K{sub e}) distributions are obtained for single plasma plumes (S{sub p}) and colliding plasma plumes (C{sub p}). The charge yield from a C{sub p} relative to twice that from a S{sub p} is characterized by a charge yield ratio (CYR) parameter. Superior ion yields for all charge states occur for a discrete range of fluences (F) from colliding plasma plumes leading to a CYR parameter exceeding unity. The kinetic energy distributions from colliding plasma plumes display well defined energy compression via narrowing of the distributions for all fluences and charge states. The extent of this energy compression is charge dependent. Space charge forces within the stagnation layer and the resulting charge dependent acceleration of ions are proposed to account for the transfer of ion kinetic energy in favour of collisional ionization mechanisms.

  5. New technology for linear colliders

    SciTech Connect

    McIntyre, P.M.

    1991-08-01

    The purpose of this contract is to develop and evaluate new technology for future e{sup +}e{sup {minus}} linac colliders. TeV linac colliders will require major improvements in the performance of microwave power tubes: >100 mW/m peak power, {approximately}20 GHz frequency, and high frequency. For the past three years we have been developing gigatron, a new design concept for microwave power tubes. It incorporates three key innovations: a gated field-emitter cathode which produces a fully modulated electron beam directly into the vacuum; a ribbon beam geometry which eliminates space charge and phase dispersion, and a traveling wave coupler which provides optimum output coupling even over a wide ribbon beam. During the past year we have built prototypes of two cathode designs: a stripline edge-emitter array and a porous silicon dioxide cathode. A highlight of our results is the development and testing of the porous SiO{sub 2} cathode. It delivers exceptional performance as a modulated electron source in general and for gigatron in particular. Its high emitter density and low work function accommodate higher tube gain, simpler cathode coupling, and higher peak power than any other technology. The protection of the active emitting surface by {approximately}2 {mu}m of porous SiO{sub 2} should provide for rugged operation in a tube environment.

  6. Hadron colliders (SSC/LHC)

    SciTech Connect

    Chao, A.W.; Palmer, R.B.; Evans, L.; Gareyte, J.; Siemann, R.H.

    1992-12-31

    The nominal SSC and LHC designs should operate conservatively at luminosities up to 10{sup 33} cm{sup {minus}2} s{sup {minus}1}. This luminosity is dictated by the event rates that can be handled by the detectors. However, this limit is event dependent (e.g. it does not take much of a detector to detect the event pp {yields} elephant; all one needs is extremely high luminosity). As such, it is useful to explore the possibility of going beyond the 10{sup 33} cm{sup {minus}2} s{sup {minus}1} level. Such exploration will also improve the accelerator physics understanding of pp collider designs. If the detector limitations are removed, the first accelerator limits occur when the luminosity is at the level of 10{sup 34} cm{sup {minus}2}s{sup {minus}1}. These accelerator limits will first be reviewed. The authors will then continue on to explore even higher luminosity as the ultimate limit of pp colliders. Accelerator technologies needed to achieve this ultimate luminosity as well as the R and D needed to reach it are discussed.

  7. Very large hadron collider (VLHC)

    SciTech Connect

    1998-09-01

    A VLHC informal study group started to come together at Fermilab in the fall of 1995 and at the 1996 Snowmass Study the parameters of this machine took form. The VLHC as now conceived would be a 100 TeV hadron collider. It would use the Fermilab Main Injector (now nearing completion) to inject protons at 150 GeV into a new 3 TeV Booster and then into a superconducting pp collider ring producing 100 TeV c.m. interactions. A luminosity of {approximately}10{sup 34} cm{sup -2}s{sup -1} is planned. Our plans were presented to the Subpanel on the Planning for the Future of US High- Energy Physics (the successor to the Drell committee) and in February 1998 their report stated ``The Subpanel recommends an expanded program of R&D on cost reduction strategies, enabling technologies, and accelerator physics issues for a VLHC. These efforts should be coordinated across laboratory and university groups with the aim of identifying design concepts for an economically and technically viable facility`` The coordination has been started with the inclusion of physicists from Brookhaven National Laboratory (BNL), Lawrence Berkeley National Laboratory (LBNL), and Cornell University. Clearly, this collaboration must expanded internationally as well as nationally. The phrase ``economically and technically viable facility`` presents the real challenge.

  8. The muon collider (Sandro's snake)

    SciTech Connect

    Ruggiero, A.G.

    1992-01-01

    This paper describes a feasibility study for the design of a muon collider. Recognized the fact that the particle lifetime increases linearly with the energy, we have adopted a scheme where steps of cooling and acceleration are entwined. We have indeed found convenient to accelerate the beam as fast as possible to increase its chances of survival, and necessary to dilute the action of cooling throughout the entire accelerating process to make it more effective and affordable. All acceleration and cooling steps are executed in a single pass essentially along a curvilinear and open path. We do not believe it is possible to handle the beam otherwise in circular and closed rings, as it has been proposed in the past. The example shown in this paper describes a muon collider at the energy of 250 GeV per beam and a luminosity of 4 [times] 10[sup 28] cm[sup [minus]2]s[sup [minus]1]. We have adopted an extrapolation of the stochastic cooling method for the reduction of the beam emittance.

  9. Physics and technology of the next linear collider

    SciTech Connect

    1996-06-01

    The authors present the prospects for the next generation of high-energy physics experiments with electron-positron colliding beams. This report summarizes the current status of the design and technological basis of a linear collider of center-of-mass energy 0.5--1.5 TeV, and the opportunities for high-energy physics experiments that this machine is expected to open. The physics goals discussed here are: Standard Model processes and simulation; top quark physics; Higgs boson searches and properties; supersymmetry; anomalous gauge boson couplings; strong WW scattering; new gauge bosons and exotic particles; e{sup {minus}}e{sup {minus}}, e{sup {minus}}{gamma}, and {gamma}{gamma} interactions; and precision tests of QCD.

  10. Non-collider searches for stable massive particles

    NASA Astrophysics Data System (ADS)

    Burdin, S.; Fairbairn, M.; Mermod, P.; Milstead, D.; Pinfold, J.; Sloan, T.; Taylor, W.

    2015-06-01

    The theoretical motivation for exotic stable massive particles (SMPs) and the results of SMP searches at non-collider facilities are reviewed. SMPs are defined such that they would be sufficiently long-lived so as to still exist in the cosmos either as Big Bang relics or secondary collision products, and sufficiently massive such that they are typically beyond the reach of any conceivable accelerator-based experiment. The discovery of SMPs would address a number of important questions in modern physics, such as the origin and composition of dark matter and the unification of the fundamental forces. This review outlines the scenarios predicting SMPs and the techniques used at non-collider experiments to look for SMPs in cosmic rays and bound in matter. The limits so far obtained on the fluxes and matter densities of SMPs which possess various detection-relevant properties such as electric and magnetic charge are given.

  11. Design and performance of the Stanford Linear Collider Control System

    SciTech Connect

    Melen, R.E.

    1984-10-01

    The success of the Stanford Linear Collider (SLC) will be dependent upon the implementation of a very large advanced computer-based instrumentation and control system. This paper describes the architectural design of this system as well as a critique of its performance. This critique is based on experience obtained from its use in the control and monitoring of 1/3 of the SLAC linac and in support of an expensive experimental machine physics experimental program. 11 references, 3 figures.

  12. COMPILATION OF CURRENT HIGH ENERGY PHYSICS EXPERIMENTS

    SciTech Connect

    Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.; Horne, C.P.; Hutchinson, M.S.; Rittenberg, A.; Trippe, T.G.; Yost, G.P.; Addis, L.; Ward, C.E.W.; Baggett, N.; Goldschmidt-Clermong, Y.; Joos, P.; Gelfand, N.; Oyanagi, Y.; Grudtsin, S.N.; Ryabov, Yu.G.

    1981-05-01

    This is the fourth edition of our compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and nine participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about April 1981, and (2) had not completed taking of data by 1 January 1977. We emphasize that only approved experiments are included.

  13. Research and Development of Future Muon Collider

    SciTech Connect

    Yonehara, K.; /Fermilab

    2012-05-01

    Muon collider is a considerable candidate of the next generation high-energy lepton collider machine. A novel accelerator technology must be developed to overcome several intrinsic issues of muon acceleration. Recent research and development of critical beam elements for a muon accelerator, especially muon beam phase space ionization cooling channel, are reviewed in this paper.

  14. Search for top quark at Fermilab Collider

    SciTech Connect

    Sliwa, K.; The CDF Collaboration

    1991-10-01

    The status of a search for the top quark with Collider Detector at Fermilab (CDF), based on a data sample recorded during the 1988--1989 run is presented. The plans for the next Fermilab Collider run in 1992--1993 and the prospects of discovering the top quark are discussed. 19 refs., 4 figs., 2 tabs.

  15. ACCELERATION FOR A HIGH ENERGY MUON COLLIDER

    SciTech Connect

    BERG,J.S

    2000-04-07

    The authors describe a method for designing the acceleration systems for a muon collider, with particular application and examples for a high energy muon collider. This paper primarily concentrates on design considerations coming from longitudinal motion, but some transverse issues are briefly discussed.

  16. Polarization Effects at a Muon Collider

    SciTech Connect

    Parsa, Z.

    1998-11-01

    For Muon Colliders, Polarization will be a useful tool if high polarization is achievable with little luminosity loss. Formulation and effects of beam polarization and luminosity including polarization effects in Higgs resonance studies are discussed for improving precision measurements and Higgs resonance ''discovery'' capability e.g. at the First Muon Collider (FMC).

  17. Mutual colliding impact fast ignition

    NASA Astrophysics Data System (ADS)

    Winterberg, Friedwardt

    2014-09-01

    It is proposed to apply the well established colliding beam technology of high energy physics to the fast hot spot ignition of a highly compressed DT (deuterium-tritium) target igniting a larger D (deuterium) burn, by accelerating a small amount of solid deuterium, and likewise a small amount of tritium, making a head-on collision in the center of the target, projecting them through conical ducts situated at the opposite side of the target and converging in its center. In their head-on collision, the relative collision velocity is 5/3 times larger compared to the collision velocity of a stationary target. The two pieces have for this reason to be accelerated to a smaller velocity than would otherwise be needed to reach upon impact the same temperature. Since the velocity distribution of the two head-on colliding projectiles is with its two velocity peaks non-Maxwellian, the maximum cross section velocity product turns out to be substantially larger than the maximum if averaged over a Maxwellian. The D and T projectiles would have to be accelerated with two sabots driven by powerful particle or laser beams, permitting a rather large acceleration length. With the substantially larger cross section-velocity product by virtue of the non-Maxwellian velocity distribution, a further advantage is that the head-on collision produces a large magnetic field by the thermomagnetic Nernst effect, enhancing propagating burn. With this concept, the ignition of the neutron-less hydrogen-boron (HB11) reaction might even be possible in a heterogeneous assembly of the hydrogen and the boron to reduce the bremsstrahlung-losses, resembling the heterogeneous assembly in a graphite-natural uranium reactor, there to reduce the neutron losses.

  18. Mutual colliding impact fast ignition

    SciTech Connect

    Winterberg, Friedwardt

    2014-09-15

    It is proposed to apply the well established colliding beam technology of high energy physics to the fast hot spot ignition of a highly compressed DT (deuterium-tritium) target igniting a larger D (deuterium) burn, by accelerating a small amount of solid deuterium, and likewise a small amount of tritium, making a head-on collision in the center of the target, projecting them through conical ducts situated at the opposite side of the target and converging in its center. In their head-on collision, the relative collision velocity is 5/3 times larger compared to the collision velocity of a stationary target. The two pieces have for this reason to be accelerated to a smaller velocity than would otherwise be needed to reach upon impact the same temperature. Since the velocity distribution of the two head-on colliding projectiles is with its two velocity peaks non-Maxwellian, the maximum cross section velocity product turns out to be substantially larger than the maximum if averaged over a Maxwellian. The D and T projectiles would have to be accelerated with two sabots driven by powerful particle or laser beams, permitting a rather large acceleration length. With the substantially larger cross section-velocity product by virtue of the non-Maxwellian velocity distribution, a further advantage is that the head-on collision produces a large magnetic field by the thermomagnetic Nernst effect, enhancing propagating burn. With this concept, the ignition of the neutron-less hydrogen-boron (HB{sup 11}) reaction might even be possible in a heterogeneous assembly of the hydrogen and the boron to reduce the bremsstrahlung-losses, resembling the heterogeneous assembly in a graphite-natural uranium reactor, there to reduce the neutron losses.

  19. Critical transitions in colliding cascades

    PubMed

    Gabrielov; Keilis-Borok; Zaliapin; Newman

    2000-07-01

    We consider here the interaction of direct and inverse cascades in a hierarchical nonlinear system that is continuously loaded by external forces. The load is applied to the largest element and is transferred down the hierarchy to consecutively smaller elements, thereby forming a direct cascade. The elements of the system fail (i. e., break down) under the load. The smallest elements fail first. The failures gradually expand up the hierarchy to the larger elements, thus forming an inverse cascade. Eventually the failures heal, ensuring that the system will function indefinitely. The direct and inverse cascades collide and interact. Loading triggers the failures, while failures release and redistribute the load. Notwithstanding its relative simplicity, this model reproduces the major dynamical features observed in seismicity, including the seismic cycle, intermittence of seismic regime, power-law energy distribution, clustering in space and time, long-range correlations, and a set of seismicity patterns premonitory to a strong earthquake. In this context, the hierarchical structure of the model crudely imitates a system of tectonic blocks spread by a network of faults (note that the behavior of such a network is different from that of a single fault). Loading mimics the impact of tectonic forces, and failures simulate earthquakes. The model exhibits three basic types of premonitory pattern reflecting seismic activity, clustering of earthquakes in space and time, and the range of correlation between the earthquakes. The colliding-cascade model seemingly exhibits regularities that are common in a wide class of complex hierarchical systems, not necessarily Earth specific. PMID:11088457

  20. R&D Toward a Neutrino Factory and Muon Collider

    SciTech Connect

    Zisman, Michael S

    2009-04-29

    There is considerable interest in the use of muon beams to create either an intense source of decay neutrinos aimed at a detector located 3000-7500 km away (a Neutrino Factory), or a Muon Collider that produces high-luminosity collisions at the energy frontier. R&D aimed at producing these facilities has been under way for more than 10 years. This paper will review experimental results from MuCool, MERIT, and MICE and indicate the extent to which they will provide proof-of-principle demonstrations of the key technologies required for a Neutrino Factory or Muon Collider. Progress in constructing components for the MICE experiment will also be described.

  1. The technical challenges of the Large Hadron Collider.

    PubMed

    Collier, Paul

    2015-01-13

    The Large Hadron Collider (LHC) is a 27km circumference hadron collider, built at CERN to explore the energy frontier of particle physics. Approved in 1994, it was commissioned and began operation for data taking in 2009. The design and construction of the LHC presented many design, engineering and logistical challenges which involved pushing a number of technologies well beyond their level at the time. Since the start-up of the machine, there has been a very successful 3-year run with an impressive amount of data delivered to the LHC experiments. With an increasingly large stored energy in the beam, the operation of the machine itself presented many challenges and some of these will be discussed. Finally, the planning for the next 20 years has been outlined with progressive upgrades of the machine, first to nominal energy, then to progressively higher collision rates. At each stage the technical challenges are illustrated with a few examples. PMID:26949802

  2. Colliding Laser Pulses for Laser-Plasma Accelerator Injection Control

    SciTech Connect

    Plateau, G. R.; Geddes, C. G. R.; Matlis, N. H.; Mittelberger, D. E.; Nakamura, K.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.; Cormier-Michel, E.

    2010-11-04

    Decoupling injection from acceleration is a key challenge to achieve compact, reliable, tunable laser-plasma accelerators (LPA). In colliding pulse injection the beat between multiple laser pulses can be used to control energy, energy spread, and emittance of the electron beam by injecting electrons in momentum and phase into the accelerating phase of the wake trailing the driver laser pulse. At LBNL, using automated control of spatiotemporal overlap of laser pulses, two-pulse experiments showed stable operation and reproducibility over hours of operation. Arrival time of the colliding beam was scanned, and the measured timing window and density of optimal operation agree with simulations. The accelerator length was mapped by scanning the collision point.

  3. Colliding Laser Pulses for Laser-Plasma Accelerator Injection Control

    NASA Astrophysics Data System (ADS)

    Plateau, G. R.; Geddes, C. G. R.; Matlis, N. H.; Cormier-Michel, E.; Mittelberger, D. E.; Nakamura, K.; Schroeder, C. B.; Esarey, E.; Leemans, W. P.

    2010-11-01

    Decoupling injection from acceleration is a key challenge to achieve compact, reliable, tunable laser-plasma accelerators (LPA) [1, 2]. In colliding pulse injection the beat between multiple laser pulses can be used to control energy, energy spread, and emittance of the electron beam by injecting electrons in momentum and phase into the accelerating phase of the wake trailing the driver laser pulse [3, 4, 5, 6, 7]. At LBNL, using automated control of spatiotemporal overlap of laser pulses, two-pulse experiments showed stable operation and reproducibility over hours of operation. Arrival time of the colliding beam was scanned, and the measured timing window and density of optimal operation agree with simulations [8]. The accelerator length was mapped by scanning the collision point.

  4. Higgs Boson Searches at Hadron Colliders (1/4)

    ScienceCinema

    None

    2011-10-06

    In these Academic Training lectures, the phenomenology of Higgs bosons and search strategies at hadron colliders are discussed. After a brief introduction on Higgs bosons in the Standard Model and a discussion of present direct and indirect constraints on its mass the status of the theoretical cross section calculations for Higgs boson production at hadron colliders is reviewed. In the following lectures important experimental issues relevant for Higgs boson searches (trigger, measurements of leptons, jets and missing transverse energy) are presented. This is followed by a detailed discussion of the discovery potential for the Standard Model Higgs boson for both the Tevatron and the LHC experiments. In addition, various scenarios beyond the Standard Model, primarily the MSSM, are considered. Finally, the potential and strategies to measured Higgs boson parameters and the investigation of alternative symmetry breaking scenarios are addressed.

  5. Optimizing integrated luminosity of future hadron colliders

    NASA Astrophysics Data System (ADS)

    Benedikt, Michael; Schulte, Daniel; Zimmermann, Frank

    2015-10-01

    The integrated luminosity, a key figure of merit for any particle-physics collider, is closely linked to the peak luminosity and to the beam lifetime. The instantaneous peak luminosity of a collider is constrained by a number of boundary conditions, such as the available beam current, the maximum beam-beam tune shift with acceptable beam stability and reasonable luminosity lifetime (i.e., the empirical "beam-beam limit"), or the event pileup in the physics detectors. The beam lifetime at high-luminosity hadron colliders is largely determined by particle burn off in the collisions. In future highest-energy circular colliders synchrotron radiation provides a natural damping mechanism, which can be exploited for maximizing the integrated luminosity. In this article, we derive analytical expressions describing the optimized integrated luminosity, the corresponding optimum store length, and the time evolution of relevant beam parameters, without or with radiation damping, while respecting a fixed maximum value for the total beam-beam tune shift or for the event pileup in the detector. Our results are illustrated by examples for the proton-proton luminosity of the existing Large Hadron Collider (LHC) at its design parameters, of the High-Luminosity Large Hadron Collider (HL-LHC), and of the Future Circular Collider (FCC-hh).

  6. Compensatable muon collider calorimeter with manageable backgrounds

    SciTech Connect

    Raja, Rajendran

    2015-02-17

    A method and system for reducing background noise in a particle collider, comprises identifying an interaction point among a plurality of particles within a particle collider associated with a detector element, defining a trigger start time for each of the pixels as the time taken for light to travel from the interaction point to the pixel and a trigger stop time as a selected time after the trigger start time, and collecting only detections that occur between the start trigger time and the stop trigger time in order to thereafter compensate the result from the particle collider to reduce unwanted background detection.

  7. Beamstrahlung spectra in next generation linear colliders

    SciTech Connect

    Barklow, T.; Chen, P. ); Kozanecki, W. )

    1992-04-01

    For the next generation of linear colliders, the energy loss due to beamstrahlung during the collision of the e{sup +}e{sup {minus}} beams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e{sup +}e{sup {minus}} and {gamma}{gamma} differential luminosities. We then apply our formulation to various classes of 500 GeV e{sup +}e{sup {minus}} linear collider designs currently under study.

  8. SLAC linear collider conceptual design report

    SciTech Connect

    Not Available

    1980-06-01

    The linear collider system is described in detail, including the transport system, the collider lattice, final focusing system, positron production, beam damping and compression, high current electron source, instrumentation and control, and the beam luminosity. The experimental facilities and the experimental uses are discussed along with the construction schedule and estimated costs. Appendices include a discussion of space charge effects in the linear accelerator, emittance growth in the collider, the final focus system, beam-beam instabilities and pinch effects, and detector backgrounds. (GHT)

  9. The principles and construction of linear colliders

    SciTech Connect

    Rees, J.

    1986-09-01

    The problems posed to the designers and builders of high-energy linear colliders are discussed. Scaling laws of linear colliders are considered. The problem of attainment of small interaction areas is addressed. The physics of damping rings, which are designed to condense beam bunches in phase space, is discussed. The effect of wake fields on a particle bunch in a linac, particularly the conventional disk-loaded microwave linac structures, are discussed, as well as ways of dealing with those effects. Finally, the SLAC Linear Collider is described. 18 refs., 17 figs. (LEW)

  10. Electron-ion collider eRHIC

    NASA Astrophysics Data System (ADS)

    Litvinenko, Vladimir N.

    In this article, we describe our planned future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference [1]. We plan to add a polarized electron beam with energy tunable within the 5-30-GeV range to collide with variety of species in the existing RHIC accelerator complex, from polarized protons with a maximum energy of 250 GeV, to heavy, fully striped ions with energies up to 100 GeV/u.

  11. Proposal for Research and Development: Vertexing, Tracking, and Data Acquisition for the Bottom Collider Detector

    SciTech Connect

    Castro, H.; Gomez, B.; Rivera, F.; Sanabria, J.-C.; Yager, P.; Barsotti, E.; Bowden, M.; Childress, S.; Lebrun, P.; Morfin, J.; Roberts, L.A.; /Fermilab /Florida U. /Houston U. /IIT /Iowa U. /Northeastern U. /Northern Illinois U. /Ohio State U. /Oklahoma U. /Pennsylvania U.

    1989-01-01

    The authors propose a program of research and development into the detector systems needed for a B-physics experiment at the Fermilab p-{bar p} Collider. The initial emphasis is on the critical issues of vertexting, tracking, and data acquisition in the high-multiplicity, high-rate collider environment. R and D for the particle-identification systems (RICH counters, TRD's, and EM calorimeter) will be covered in a subsequent proposal. To help focus their efforts in a timely manner, they propose the first phase of the R and D should culminate in a system test at the C0 collider intersect during the 1990-1991 run: a small fraction of the eventual vertex detector would be used to demonstrate that secondary-decay vertices can be found at a hadron collider. The proposed budget for the r and D program is $800k in 1989, $1.5M in 1990, and $1.6M in 1991.

  12. Nonglobal correlations in collider physics

    DOE PAGESBeta

    Moult, Ian; Larkoski, Andrew J.

    2016-01-13

    Despite their importance for precision QCD calculations, correlations between in- and out-of-jet regions of phase space have never directly been observed. These so-called non-global effects are present generically whenever a collider physics measurement is not explicitly dependent on radiation throughout the entire phase space. In this paper, we introduce a novel procedure based on mutual information, which allows us to isolate these non-global correlations between measurements made in different regions of phase space. We study this procedure both analytically and in Monte Carlo simulations in the context of observables measured on hadronic final states produced in e+e- collisions, though itmore » is more widely applicable.The procedure exploits the sensitivity of soft radiation at large angles to non-global correlations, and we calculate these correlations through next-to-leading logarithmic accuracy. The bulk of these non-global correlations are found to be described in Monte Carlo simulation. They increase by the inclusion of non-perturbative effects, which we show can be incorporated in our calculation through the use of a model shape function. As a result, this procedure illuminates the source of non-global correlations and has connections more broadly to fundamental quantities in quantum field theory.« less

  13. Nonglobal correlations in collider physics

    NASA Astrophysics Data System (ADS)

    Larkoski, Andrew J.; Moult, Ian

    2016-01-01

    Despite their importance for precision QCD calculations, correlations between in- and out-of-jet regions of phase space have never directly been observed. These so-called nonglobal effects are present generically whenever a collider physics measurement is not explicitly dependent on radiation throughout the entire phase space. In this paper, we introduce a novel procedure based on mutual information, which allows us to isolate these nonglobal correlations between measurements made in different regions of phase space. We study this procedure both analytically and in Monte Carlo simulations in the context of observables measured on hadronic final states produced in e+e- collisions, though it is more widely applicable. The procedure exploits the sensitivity of soft radiation at large angles to nonglobal correlations, and we calculate these correlations through next-to-leading logarithmic accuracy. The bulk of these nonglobal correlations are found to be described in Monte Carlo simulation. They increase by the inclusion of nonperturbative effects, which we show can be incorporated in our calculation through the use of a model shape function. This procedure illuminates the source of nonglobal correlations and has connections more broadly to fundamental quantities in quantum field theory.

  14. Vertex detectors and the linear collider

    NASA Astrophysics Data System (ADS)

    Damerell, C. J. S.

    2006-11-01

    We review the physics requirements for the ILC vertex detectors, which lead to the specification of silicon pixel sensors arranged as nested barrels, possibly augmented by endcap detectors for enhanced coverage of small polar angles. We describe how the detector requirements are a natural outgrowth of 25 years development of CCD-based vertex detectors in fixed-target and colliding beam experiments, culminating in the 307 Mpixel SLD vertex detector. We discuss how the technology has recently branched out into about a dozen architectures which might be made to work at the ILC, where the main challenge is to increase the effective readout rate by about a factor 1000 compared to conventional CCDs, while preserving the small pixels (˜20 μm) and low-power dissipation. Preserving gaseous cooling as at SLD opens the door to layer thicknesses as low as 0.1% X0. Finally, we consider how best to manage electromagnetic interference associated with the beam wakefields and other RF sources during the bunch train. In conclusion, we suggest a strategy for moving on from the present rich R&D programmes to optimal detectors for the startup of the ILC physics programme.

  15. Electron Lenses for the Large Hadron Collider

    SciTech Connect

    Stancari, Giulio; Valishev, Alexander; Bruce, Roderik; Redaelli, Stefano; Rossi, Adriana; Salvachua, Belen

    2014-07-01

    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 RHIC at BNL. Within the US LHC Accelerator Research Program and the European HiLumi LHC Design Study, hollow electron beam collimation was studied as an option to complement the collimation system for the LHC upgrades. This project is moving towards a technical design in 2014, with the goal to build the devices in 2015-2017, after resuming LHC operations and re-assessing needs and requirements at 6.5 TeV. 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.

  16. Governance of the International Linear Collider Project

    SciTech Connect

    Foster, B.; Barish, B.; Delahaye, J.P.; Dosselli, U.; Elsen, E.; Harrison, M.; Mnich, J.; Paterson, J.M.; Richard, F.; Stapnes, S.; Suzuki, A.; Wormser, G.; Yamada, S.; /KEK, Tsukuba

    2012-05-31

    Governance models for the International Linear Collider Project are examined in the light of experience from similar international projects around the world. Recommendations for one path which could be followed to realize the ILC successfully are outlined. The International Linear Collider (ILC) is a unique endeavour in particle physics; fully international from the outset, it has no 'host laboratory' to provide infrastructure and support. The realization of this project therefore presents unique challenges, in scientific, technical and political arenas. This document outlines the main questions that need to be answered if the ILC is to become a reality. It describes the methodology used to harness the wisdom displayed and lessons learned from current and previous large international projects. From this basis, it suggests both general principles and outlines a specific model to realize the ILC. It recognizes that there is no unique model for such a laboratory and that there are often several solutions to a particular problem. Nevertheless it proposes concrete solutions that the authors believe are currently the best choices in order to stimulate discussion and catalyze proposals as to how to bring the ILC project to fruition. The ILC Laboratory would be set up by international treaty and be governed by a strong Council to whom a Director General and an associated Directorate would report. Council would empower the Director General to give strong management to the project. It would take its decisions in a timely manner, giving appropriate weight to the financial contributions of the member states. The ILC Laboratory would be set up for a fixed term, capable of extension by agreement of all the partners. The construction of the machine would be based on a Work Breakdown Structure and value engineering and would have a common cash fund sufficiently large to allow the management flexibility to optimize the project's construction. Appropriate contingency, clearly

  17. LINEAR COLLIDER PHYSICS RESOURCE BOOK FOR SNOWMASS 2001.

    SciTech Connect

    ABE,T.; DAWSON,S.; HEINEMEYER,S.; MARCIANO,W.; PAIGE,F.; TURCOT,A.S.; ET AL

    2001-05-03

    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 decade 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 {minus}} 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 {minus}} 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 {minus}} linear collider; in any scenario that is now discussed, physics will benefit from the new information that e{sup +}e{sup {minus}} experiments can provide.

  18. Linear accelerators for TeV colliders

    SciTech Connect

    Wilson, P.B.

    1985-05-01

    This paper summarizes four tutorial lectures on linear electron accelerators: Electron Linacs for TeV Colliders, Emittance and Damping Rings, Wake Fields: Basic Concepts, and Wake Field Effects in Linacs.

  19. The Status of the International Linear Collider

    NASA Astrophysics Data System (ADS)

    Harrison, Michael

    2016-03-01

    The International Linear Collider is under consideration in Japan as the next major global high energy physics facility. In this talk we shall describe the site and accelerator footprint together with the latest technical information on the superconducting RF technology.

  20. Topcolor and the First Muon Collider

    SciTech Connect

    Hill, C.T.

    1998-04-01

    We describe a class of models of electroweak symmetry breaking that involve strong dynamics and top quark condensation. A new scheme based upon a seesaw mechanism appears particularly promising. Various implications for the first-stage muon collider are discussed.

  1. Heavy flavor physics at hadron colliders

    SciTech Connect

    Barbaro-Galtieri, A.

    1991-12-01

    The search for the top quark has dominated heavy flavor physics at hadron colliders. For Standard model decay of top the present mass limit in m{sub t} > 89 GeV (95% C.L.). Bottom production cross sections are quite large at hadron colliders, thus providing enough statistics for extensive studies. Results on cross sections, B{sup 0} {minus} {bar B}{sup 0} mixing, exclusive channels and rare B decays will be summarized.

  2. RF pulse compression for future linear colliders

    SciTech Connect

    Wilson, P.B.

    1995-05-01

    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 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-11 system) can be used to reduce the klystron peak power by about a factor of two, or alternately, 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.

  3. Accelerator considerations of large circular colliders

    NASA Astrophysics Data System (ADS)

    Chao, Alex

    2016-07-01

    As we consider the tremendous physics reaches of the big future circular electron-positron and proton-proton colliders, it might be advisable to keep a close track of what accelerator challenges they face. Good progresses are being made, and yet it is reported here that substantial investments in funding, manpower, as well as a long sustained time to the R&D efforts will be required in preparation to realize these dream colliders.

  4. Photon Linear Collider Gamma-Gamma Summary

    SciTech Connect

    Gronberg, J

    2012-02-27

    High energy photon - photon collisions can be achieved by adding high average power short-pulse lasers to the Linear Collider, enabling an expanded physics program for the facility. The technology required to realize a photon linear collider continues to mature. Compton back-scattering technology is being developed around the world for low energy light source applications and high average power lasers are being developed for Inertial Confinement Fusion.

  5. World lays groundwork for future linear collider

    SciTech Connect

    Feder, Toni

    2010-07-15

    With the Large Hadron Collider at CERN finally working, the particle-physics community can now afford to divide its attention between achieving LHC results and preparing for the next machine on its wish list, an electron-positron linear collider. The preparations involve developing and deciding on the technology for such a machine, the mode of its governance, and how to balance regional and global particle- and accelerator-physics programs.

  6. Signal of doubly charged Higgs at e+e- colliders

    NASA Astrophysics Data System (ADS)

    Hue, L. T.; Huong, D. T.; Long, H. N.; Hung, H. T.; Thao, N. H.

    2015-11-01

    The masses and signals of the production of doubly charged Higgses (DCH) in the framework of the supersymmetric reduced minimal 3-3-1 model are investigated. In the DCH sector, we prove that there always exists a region of the parameter space where the mass of the lightest DCH is of the order of O(100) GeV even when all other new particles are very heavy. The lightest DCH mainly decays to two same-sign leptons while the dominant decay channels of the heavy DCHs are those decaying to heavy particles. We analyze each production cross section for e^+e^- ⇒ H^{++} H^{-} as a function of a few kinematic variables, which are useful to discuss the creation of DCHs in e^+e^- colliders as an indicator of new physics beyond the Standard Model. A numerical study shows that the cross sections for creating the lightest DCH can reach values of a few pb. The other two DCHs are too heavy, beyond the observable range of experiments. The lightest DCH may be detected by the International Linear Collider or the Compact Linear Collider by searching for its decay to a same-sign charged lepton pair.

  7. Low-cost hadron colliders at Fermilab: A discussion paper

    SciTech Connect

    Foster, G.W.; Malamud, E.

    1996-06-21

    New more economic approaches are required to continue the dramatic exponential rise in collider energies as represented by the well known Livingston plot. The old idea of low cost, low field iron dominated magnets in a small diameter pipe may become feasible in the next decade with dramatic recent advances in technology: (1) advanced tunneling technologies for small diameter, non human accessible tunnels, (2) accurate remote guidance systems for tunnel survey and boring machine steering, (3) high T{sub c} superconductors operating at liquid N{sub 2} or liquid H{sub 2} temperatures, (4) industrial applications of remote manipulation and robotics, (5) digitally multiplexed electronics to minimize cables, (6) achievement of high luminosities in p-p and p-{anti P} colliders. The goal of this paper is to stimulate continuing discussions on approaches to this new collider and to identify critical areas needing calculations, construction of models, proof of principle experiments, and full scale prototypes in order to determine feasibility and arrive at cost estimates.

  8. Future proton and electron colliders: Dreams for the 1990's

    SciTech Connect

    Richter, B.

    1988-10-01

    In this paper I have reviewed the possibilities for new colliders that might be available in the 1990's. One or more new proton should be available in the late-90s based on plans of Europe, the US and the USSR. The two very high energy machines, LHC and SSC, are quite expensive, and their construction will be more decided by the politicians' view on the availability of resources than by the physicists' view of the need for new machines. Certainly something will be built, but the question is when. New electron colliders beyond LEP II could be available in the late 1990's as well. Most of the people who have looked at this problem believe that at a minimum three years of RandD are required before a proposal can be made, two years will be required to convince the authorities to go ahead, and five years will be required to build such a machine. Thus the earliest time a new electron collider at high energy could be available is around 1988. A strong international RandD program will be required to meet that schedule. In the field of B factories, PSI's proposal is the first serious step beyond the capabilities of CESR. There are other promising techniques but these need more RandD. The least RandD would be required for the asymmetric storage ring systems, while the most would be required for high luminosity linear colliders. For the next decade, high energy physics will be doing its work at the high energy frontier with Tevatron I and II, UNK, SLC, LEP I and II, and HERA. The opportunities for science presented by experiments at these facilities are very great, and it is to be hoped that the pressure for funding to construct the next generation facilities will not badly affect the operating budgets of the ones we now have or which will soon be turning on. 9 refs., 12 figs., 6 tabs.

  9. Current experiments in particle physics - particle data group

    SciTech Connect

    Galic, H.; Lehar, F.; Kettle, P.R.

    1996-09-01

    This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries.

  10. Taking Energy to the Physics Classroom from the Large Hadron Collider at CERN

    ERIC Educational Resources Information Center

    Cid, Xabier; Cid, Ramon

    2009-01-01

    In 2008, the greatest experiment in history began. When in full operation, the Large Hadron Collider (LHC) at CERN will generate the greatest amount of information that has ever been produced in an experiment before. It will also reveal some of the most fundamental secrets of nature. Despite the enormous amount of information available on this…

  11. T864 (MiniMax): A search for disoriented chiral condensate at the Fermilab Collider

    SciTech Connect

    Bjorken, J.D.

    1996-10-01

    A small test/experiment has been performed at the Fermilab Collider to measure charged particle and photon multiplicities in the forward direction, {eta} {approximately} 4.1. The primary goal is to search for disoriented chiral condensate (DCC). The experiment and analysis methods are described, and preliminary results of the DCC search are presented.

  12. Ecloud Build-Up Simulations for the FNAL MI for a Mixed Fill Pattern: Dependence on Peak SEY and Pulse Intensity During the Ramp

    SciTech Connect

    Furman, M. A.

    2010-12-11

    We present simulation results of the build-up of the electron-cloud density n{sub e} in three regions of the FNAL Main Injector (MI) for a beam fill pattern made up of 5 double booster batches followed by a 6th single batch. We vary the pulse intensity in the range N{sub t} = (2-5) x 10{sup 13}, and the beam kinetic energy in the range E{sub k} = 8-120 GeV. We assume a secondary electron emission model qualitatively corresponding to TiN, except that we let the peak value of the secondary electron yield (SEY) {delta}{sub max} vary as a free parameter in a fairly broad range. Our main conclusions are: (1) At fixed N{sub t} there is a clear threshold behavior of n{sub e} as a function of {delta}{sub max} in the range {approx} 1.1-1.3. (2) At fixed {delta}{sub max}, there is a threshold behavior of n{sub e} as a function of N{sub t} provided {delta}{sub max} is sufficiently high; the threshold value of N{sub t} is a function of the characteristics of the region being simulated. (3) The dependence on E{sub k} is weak except possibly at transition energy. Most of these results were informally presented to the relevant MI personnel in April 2010.

  13. Beyond standard model physics at current and future colliders

    NASA Astrophysics Data System (ADS)

    Liu, Zhen

    The Large Hadron Collider (LHC), a multinational experiment which began running in 2009, is highly expected to discover new physics that will help us understand the nature of the universe and begin to find solutions to many of the unsolved puzzles of particle physics. For over 40 years the Standard Model has been the accepted theory of elementary particle physics, except for one unconfirmed component, the Higgs boson. The experiments at the LHC have recently discovered this Standard-Model-like Higgs boson. This discovery is one of the most exciting achievements in elementary particle physics. Yet, a profound question remains: Is this rather light, weakly-coupled boson nothing but a Standard Model Higgs or a first manifestation of a deeper theory? Also, the recent discoveries of neutrino mass and mixing, experimental evidences of dark matter and dark energy, matter-antimatter asymmetry, indicate that our understanding of fundamental physics is currently incomplete. For the next decade and more, the LHC and future colliders will be at the cutting-edge of particle physics discoveries and will shed light on many of these unanswered questions. There are many promising beyond-Standard-Model theories that may help solve the central puzzles of particle physics. To fill the gaps in our knowledge, we need to know how these theories will manifest themselves in controlled experiments, such as high energy colliders. I discuss how we can probe fundamental physics at current and future colliders directly through searches for new phenomena such as resonances, rare Higgs decays, exotic displaced signatures, and indirectly through precision measurements on Higgs in this work. I explore beyond standard model physics effects from different perspectives, including explicit models such as supersymmetry, generic models in terms of resonances, as well as effective field theory approach in terms of higher dimensional operators. This work provides a generic and broad overview of the physics

  14. String resonances at hadron colliders

    NASA Astrophysics Data System (ADS)

    Anchordoqui, Luis A.; Antoniadis, Ignatios; Dai, De-Chang; Feng, Wan-Zhe; Goldberg, Haim; Huang, Xing; Lüst, Dieter; Stojkovic, Dejan; Taylor, Tomasz R.

    2014-09-01

    We consider extensions of the standard model based on open strings ending on D-branes, with gauge bosons due to strings attached to stacks of D-branes and chiral matter due to strings stretching between intersecting D-branes. Assuming that the fundamental string mass scale Ms is in the TeV range and that the theory is weakly coupled, we discuss possible signals of string physics at the upcoming HL-LHC run (integrated luminosity =3000 fb-1) with a center-of-mass energy of √s =14 TeV and at potential future pp colliders, HE-LHC and VLHC, operating at √s =33 and 100 TeV, respectively (with the same integrated luminosity). In such D-brane constructions, the dominant contributions to full-fledged string amplitudes for all the common QCD parton subprocesses leading to dijets and γ +jet are completely independent of the details of compactification and can be evaluated in a parameter-free manner. We make use of these amplitudes evaluated near the first (n=1) and second (n=2) resonant poles to determine the discovery potential for Regge excitations of the quark, the gluon, and the color singlet living on the QCD stack. We show that for string scales as large as 7.1 TeV (6.1 TeV) lowest massive Regge excitations are open to discovery at the ≥5σ in dijet (γ +jet) HL-LHC data. We also show that for n=1 the dijet discovery potential at HE-LHC and VLHC exceedingly improves: up to 15 TeV and 41 TeV, respectively. To compute the signal-to-noise ratio for n=2 resonances, we first carry out a complete calculation of all relevant decay widths of the second massive level string states (including decays into massless particles and a massive n=1 and a massless particle), where we rely on factorization and conformal field theory techniques. Helicity wave functions of arbitrary higher spin massive bosons are also constructed. We demonstrate that for string scales Ms≲10.5 TeV (Ms≲28 TeV) detection of n =2 Regge recurrences at HE-LHC (VLHC) would become the smoking gun for D

  15. PROSPECTS FOR COLLIDERS AND COLLIDER PHYSICS TO THE 1 PEV ENERGY SCALE

    SciTech Connect

    KING,B.J.

    2000-05-05

    A review is given of the prospects for future colliders and collider physics at the energy frontier. A proof-of-plausibility scenario is presented for maximizing the authors progress in elementary particle physics by extending the energy reach of hadron and lepton colliders as quickly and economically as might be technically and financially feasible. The scenario comprises 5 colliders beyond the LHC--one each of e{sup +}e{sup {minus}} and hadron colliders and three {mu}{sup +}{mu}{sup {minus}} colliders--and is able to hold to the historical rate of progress in the log-energy reach of hadron and lepton colliders, reaching the 1 PeV constituent mass scale by the early 2040's. The technical and fiscal requirements for the feasibility of the scenario are assessed and relevant long-term R and D projects are identified. Considerations of both cost and logistics seem to strongly favor housing most or all of the colliders in the scenario in a new world high energy physics laboratory.

  16. Physics at the e⁺e⁻ linear collider

    DOE PAGESBeta

    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.

  17. CLIC Project Overview (In Conjunction with the Muon Collider Workshop)

    ScienceCinema

    Latina, Andrea

    2010-01-08

    The CLIC study is exploring the scheme for an electron-positron collider with a centre-of-mass energy of 3 TeV in order to make the multi-TeV range accessible for physics. The current goal of the project is to demonstrate the feasibility of the technology by the year 2010. Recently, important progress has been made concerning the high-gradient accelerating structure tests and the experiments with beam in the CLIC test facility, CTF3. On the organizational side, the CLIC international collaborations have significantly gained momentum, boosting the CLIC study.

  18. Superconducting final focus for the SLAC Linear Collider

    SciTech Connect

    Ash, W.W.; Barrera, F.; Burgess, W.; Cook, K.; Cutler, H.; Ferrie, J.; Petersen, H.; Sawyer, D.; Rinta, R.

    1992-05-01

    Triplets composed of superconducting quadrupoles have been built and installed as the final focusing element for the high-energy positron and electron beams of the SLAC Linear Collider. Special features include independent alignment to 100-micron tolerance inside a common cryostat; non-magnetic materials to allow operation inside the detector`s solenoid field; a continuous-flow helium-only system using 50-meter-long flexible transfer lines; and complete operation of the system before installation. The mechanical design and cryogenic operation experience are presented.

  19. Superconducting final focus for the SLAC Linear Collider

    SciTech Connect

    Ash, W.W.; Barrera, F.; Burgess, W.; Cook, K.; Cutler, H.; Ferrie, J.; Petersen, H.; Sawyer, D.; Rinta, R.

    1992-05-01

    Triplets composed of superconducting quadrupoles have been built and installed as the final focusing element for the high-energy positron and electron beams of the SLAC Linear Collider. Special features include independent alignment to 100-micron tolerance inside a common cryostat; non-magnetic materials to allow operation inside the detector's solenoid field; a continuous-flow helium-only system using 50-meter-long flexible transfer lines; and complete operation of the system before installation. The mechanical design and cryogenic operation experience are presented.

  20. SSC (Superconducting Super Collider) dipole coil production tooling

    SciTech Connect

    Carson, J.A.; Barczak, E.J.; Bossert, R.C.; Brandt, J.S.; Smith, G.A.

    1989-03-01

    Superconducting Super Collider dipole coils must be produced to high precision to ensure uniform prestress and even conductor distribution within the collared coil assembly. Tooling is being prepared at Fermilab for the production of high precision 1M and 16.6M SSC dipole coils suitable for mass production. The design and construction methods builds on the Tevatron tooling and production experience. Details of the design and construction methods and measured coil uniformity of 1M coils will be presented. 4 refs., 10 figs.

  1. Stagnation and interpenetration of laser-created colliding plasmas

    SciTech Connect

    Pollaine, S.M.; Albritton, J.R.; Kauffman, R.; Keane, C.J. ); Berger, R.L.; Bosch, R.; Delameter, N.D.; Failor, B.H. )

    1990-11-05

    A KMS laser experiment collides Aluminum (A1) and Magnesium (Mg) plasmas. The measurements include electron density, time and space resolved Ly-alpha and He-alpha lines of Al and Mg, and x-ray images. These measurements were analyzed with a hydrodynamic code, LASNEX, and a special two-fluid code OFIS. The results strongly suggest that at early times, the Al interpenetrates the counterstreaming Mg and deposits in the dense Mg region. At late times, the Al plasma stagnates against the Mg plasma.

  2. Minimax: Multiparticle physics at the TeVatron collider

    SciTech Connect

    Bjorken, J.D.

    1994-01-01

    The author and two dozen others are engaged in a small test/experiment in the Fermilab Tevatron collider. It is called Minimax, and its purpose is to explore large-cross-section physics in the forward direction. The primary goal of Minimax is search for events containing the residue of disoriented chiral condensate (dcc) produced in the primary collision. The theoretical ideas are very speculative. But if they are right, they could provide an interpretation of the Centauro/anti-Centauro anomalies claimed to have been seen in cosmic-ray events. In this paper, the history and status of Minimax is described.

  3. Status of the SLAC Linear Collider Project

    SciTech Connect

    Stiening, R.

    1983-01-01

    The SLAC Linear Collider Project has two principal goals. The first is to serve as a prototype for a future very high energy linear electron-positron collider. The second is to quickly, at low cost, achieve sufficient luminosity at 100 GeV center-of-mass energy to explore the physics of the Z/sup 0/. The first goal is important to the future of electron-positron physics because the rapid increase of synchrotron radiation with energy causes the cost of circular storage ring colliders to whereas the cost of linear colliders increases only in proportion to the center-of-mass energy. The second is important because the existance at SLAC of a linear accelerator which can be converted at low cost to collider operation makes possible a unique opportunity to quickly achieve 100 GeV center-of-mass collisions. At the design luminosity of 6.0 x 10/sup 30/ many thousands of Z/sup 0/ decays should be observed in each day of operation.

  4. Top Quark Mass from the Tevatron and LHC Colliders

    NASA Astrophysics Data System (ADS)

    Brigliadori, Luca

    2015-03-01

    The discovery of the top quark in 1995 has been one of the great successes of the CDF and D0 experiments at the Fermilab Tevatron collider. Since then, many measurements of the top quark properties have been performed in different channels and using many methods. The importance of measuring its mass lies in the possibility of verifying the predictions and the consistency of the Standard Model as well as in setting constraints on possible, still unobserved, physics. In 2010, the new CERN experiments, ATLAS and CMS, started to measure the top quark properties exploiting the large amount of data collected at the Large Hadron Collider. In March 2014, the very first combination of measurements from all the four experiments has been performed yielding Mtop = 173.34 ± 0.76 GeV, with a precision below 0.5%. In these proceedings a selected review of the most recent or relevant results obtained by the Tevatron and LHC Collaborations is presented.

  5. Compilation of current high-energy physics experiments

    SciTech Connect

    Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.

    1981-05-01

    This is the fourth edition of the compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and nine participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about April 1981, and (2) had not completed taking of data by 1 January 1977. Only approved experiments are included.

  6. The Large Hadron Collider: Redefining High Energy

    SciTech Connect

    Demers, Sarah

    2007-06-19

    Particle physicists have a description of the forces of nature known as the Standard Model that has successfully withstood decades of testing at laboratories around the world. Though the Standard Model is powerful, it is not complete. Important details like the masses of particles are not explained well, and realities as fundamental as gravity, dark matter, and dark energy are left out altogether. I will discuss gaps in the model and why there is hope that some puzzles will be solved by probing high energies with the Large Hadron Collider. Beginning next year, this machine will accelerate protons to record energies, hurling them around a 27 kilometer ring before colliding them 40 million times per second. Detectors the size of five-story buildings will record the debris of these collisions. The new energy frontier made accessible by the Large Hadron Collider will allow thousands of physicists to explore nature's fundamental forces and particles from a fantastic vantage point.

  7. The Relativistic Heavy Ion Collider at Brookhaven

    SciTech Connect

    Hahn, H.

    1989-01-01

    The conceptual design of a collider capable of accelerating and colliding heavy ions and to be constructed in the existing 3.8 km tunnel at Brookhaven has been developed. The collider has been designed to provide collisions of gold ions at six intersection points with a luminosity of about 2 /times/ 10/sup 26/ cm/sup /minus/2/sec/sup /minus/1/ at an energy per nucleon of 100 GeV in each beam. Collisions with different ion species, including protons, will be possible. The salient design features and the reasons for major design choices of the proposed machine are discussed in this paper. 28 refs., 2 figs., 1 tab.

  8. Seismic studies for Fermilab future collider projects

    SciTech Connect

    Lauh, J.; Shiltsev, V.

    1997-11-01

    Ground motion can cause significant beam emittance growth and orbit oscillations in large hadron colliders due to a vibration of numerous focusing magnets. Larger accelerator ring circumference leads to smaller revolution frequency and, e.g. for the Fermilab Very Large Hadron Collider(VLHC) 50-150 Hz vibrations are of particular interest as they are resonant with the beam betatron frequency. Seismic measurements at an existing large accelerator under operation can help to estimate the vibrations generated by the technical systems in future machines. Comparison of noisy and quiet microseismic conditions might be useful for proper choice of technical solutions for future colliders. This article presents results of wide-band seismic measurements at the Fermilab site, namely, in the tunnel of the Tevatron and on the surface nearby, and in two deep tunnels in the Illinois dolomite which is though to be a possible geological environment of the future accelerators.

  9. Dynamics of laser ablated colliding plumes

    SciTech Connect

    Gupta, Shyam L.; Pandey, Pramod K.; Thareja, Raj K.

    2013-01-15

    We report the dynamics of single and two collinearly colliding laser ablated plumes of ZnO studied using fast imaging and the spectroscopic measurements. Two dimensional imaging of expanding plume and temporal evolution of various species in interacting zones of plumes are used to calculate plume front velocity, electron temperature, and density of plasma. The two expanding plumes interact with each other at early stage of expansion ({approx}20 ns) resulting in an interaction zone that propagates further leading to the formation of stagnation layer at later times (>150 ns) at the lateral collision front of two plumes. Colliding plumes have larger concentration of higher ionic species, higher temperature, and increased electron density in the stagnation region. A one-to-one correlation between the imaging and optical emission spectroscopic observations in interaction zone of the colliding plumes is reported.

  10. Collider and detector protection at beam accidents

    SciTech Connect

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

    2003-12-10

    Dealing with beam loss due to abort kicker prefire is considered for hadron colliders. The prefires occurred 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.

  11. Quirky collider signals of folded supersymmetry

    NASA Astrophysics Data System (ADS)

    Burdman, Gustavo; Chacko, Z.; Goh, Hock-Seng; Harnik, Roni; Krenke, Christopher A.

    2008-10-01

    We investigate the collider signals associated with scalar quirks (squirks) in folded supersymmetric models. As opposed to regular superpartners in supersymmetric models these particles are uncolored, but are instead charged under a new confining group, leading to radically different collider signals. Because of the new strong dynamics, squirks that are pair produced do not hadronize separately, but rather form a highly excited bound state. The excited squirkonium loses energy to radiation before annihilating back into standard model particles. We calculate the branching fractions into various channels for this process, which is prompt on collider time scales. The most promising annihilation channel for discovery is W+photon which dominates for squirkonium near its ground state. We demonstrate the feasibility of the LHC search, showing that the mass peak is visible above the SM continuum background and estimate the discovery reach.

  12. 2009 Linear Collider Workshop of the Americas

    SciTech Connect

    Seidel, Sally

    2009-09-29

    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 designs 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.

  13. The Tevatron Hadron Collider: A short history

    SciTech Connect

    Tollestrup, A.V.

    1994-11-01

    The subject of this presentation was intended to cover the history of hadron colliders. However this broad topic is probably better left to historians. I will cover a much smaller portion of this subject and specialize my subject to the history of the Tevatron. As we will see, the Tevatron project is tightly entwined with the progress in collider technology. It occupies a unique place among accelerators in that it was the first to make use of superconducting magnets and indeed the basic design now forms a template for all machines using this technology. It was spawned in an incredibly productive era when new ideas were being generated almost monthly and it has matured into our highest energy collider complete with two large detectors that provide the major facility in the US for probing high Pt physics for the coming decade.

  14. Calorimetry At Very High Energy Colliders

    SciTech Connect

    Chiu, Mickey

    2011-06-01

    The capability of hadron colliders has increased to where it will soon be possible to collide protons at center of mass energies of 14 TeV with the advent of the LHC. With increasing collision energy, calorimeters become ever more essential components of a detector, and collaborations often choose very different technologies to meet their goals. From the perspective of a high energy particle and nuclear physicist, a survey is presented of the differences in design considerations and actual performance of the wide variety of calorimeters used in modern hadron colliders such as the Tevatron, RHIC, and LHC. The lessons learned and some ideas for future development of calorimetry will also be discussed.

  15. International linear collider reference design report

    SciTech Connect

    Aarons, G.

    2007-06-22

    The International Linear Collider will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. A proposed electron-positron collider, the ILC will complement the Large Hadron Collider, a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, together unlocking some of the deepest mysteries in the universe. With LHC discoveries pointing the way, the ILC -- a true precision machine -- will provide the missing pieces of the puzzle. Consisting of two linear accelerators that face each other, the ILC will hurl some 10 billion electrons and their anti-particles, positrons, toward each other at nearly the speed of light. Superconducting accelerator cavities operating at temperatures near absolute zero give the particles more and more energy until they smash in a blazing crossfire at the centre of the machine. Stretching approximately 35 kilometres in length, the beams collide 14,000 times every second at extremely high energies -- 500 billion-electron-volts (GeV). Each spectacular collision creates an array of new particles that could answer some of the most fundamental questions of all time. The current baseline design allows for an upgrade to a 50-kilometre, 1 trillion-electron-volt (TeV) machine during the second stage of the project. This reference design provides the first detailed technical snapshot of the proposed future electron-positron collider, defining in detail the technical parameters and components that make up each section of the 31-kilometer long accelerator. The report will guide the development of the worldwide R&D program, motivate international industrial studies and serve as the basis for the final engineering design needed to make an official project proposal later this decade.

  16. Collider physics for the late 1980's

    SciTech Connect

    Hinchliffe, I.

    1987-02-27

    Topics in the Standard Model of strong and electroweak interactions and how these topics are relevant for the high energy colliders are discussed. Radiative corrections in the Glashow-Weinberg-Salam model are discussed, stressing how these corrections may be measured at LEP and the SLC. CP violation is discussed, followed by a discussion of the Higgs boson and the searches which can be carried out for it. Some features of quantum chromodynamics are discussed which are relevant to hadron colliders. Some of the problems which the Standard Model does not solve are discussed. 115 refs., 53 figs. (LEW)

  17. Top quark studies at hadron colliders

    SciTech Connect

    Sinervo, P.K.; CDF Collaboration

    1996-08-01

    The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag {ital b} quark jets in candidate events. The most recent measurements of top quark properties by the CDF and D{null} collaborations are reviewed, including the top quark cross section, mass, branching fractions and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented.

  18. Top quark studies at hadron colliders

    SciTech Connect

    Sinervo, P.K.

    1997-01-01

    The techniques used to study top quarks at hadron colliders are presented. The analyses that discovered the top quark are described, with emphasis on the techniques used to tag b quark jets in candidate events. The most recent measurements of top quark properties by the CDF and DO Collaborations are reviewed, including the top quark cross section, mass, branching fractions, and production properties. Future top quark studies at hadron colliders are discussed, and predictions for event yields and uncertainties in the measurements of top quark properties are presented.

  19. Beam instrumentation for the Tevatron Collider

    SciTech Connect

    Moore, Ronald S.; Jansson, Andreas; Shiltsev, Vladimir; /Fermilab

    2009-10-01

    The Tevatron in Collider Run II (2001-present) is operating with six times more bunches and many times higher beam intensities and luminosities than in Run I (1992-1995). Beam diagnostics were crucial for the machine start-up and the never-ending luminosity upgrade campaign. We present the overall picture of the Tevatron diagnostics development for Run II, outline machine needs for new instrumentation, present several notable examples that led to Tevatron performance improvements, and discuss the lessons for future colliders.

  20. Suppressing Electron Cloud in Future Linear Colliders

    SciTech Connect

    Pivi, M; Kirby, R.E.; Raubenheimer, T.O.; Le Pimpec, F.; /PSI, Villigen

    2005-05-27

    Any accelerator circulating positively charged beams can suffer from a build-up of an electron cloud (EC) in the beam pipe. The cloud develops through ionization of residual gases, synchrotron radiation and secondary electron emission and, when severe, can cause instability, emittance blow-up or loss of the circulating beam. The electron cloud is potentially a luminosity limiting effect for both the Large Hadron Collider (LHC) and the International Linear Collider (ILC). For the ILC positron damping ring, the development of the electron cloud must be suppressed. This paper discusses the state-of-the-art of the ongoing SLAC and international R&D program to study potential remedies.

  1. Physics Beyond the Standard Model at Colliders

    NASA Astrophysics Data System (ADS)

    Matchev, Konstantin

    These lectures introduce the modern machinery used in searches and studies of new physics Beyond the Standard Model (BSM) at colliders. The first lecture provides an overview of the main simulation tools used in high energy physics, including automated parton-level calculators, general purpose event generators, detector simulators, etc. The second lecture is a brief introduction to low energy supersymmetry (SUSY) as a representative BSM paradigm. The third lecture discusses the main collider signatures of SUSY and methods for measuring the masses of new particles in events with missing energy.

  2. FFAG Designs for Muon Collider Acceleration

    SciTech Connect

    Berg, J. Scott

    2014-01-13

    I estimate FFAG parameters for a muon collider with a 70mm longitudinal emittance. I do not discuss the lower emittance beam for a Higgs factory. I produce some example designs, giving only parameters relevant to estimating cost and performance. The designs would not track well, but the parameters of a good design will be close to those described. I compare these cost estimates to those for a fast-ramping synchrotron and a recirculating linear accelerator. I conclude that FFAGs do not appear to be cost-effective for the large longitudinal emittance in a high-energy muon collider.

  3. Luminosity measurements at hadron colliders

    SciTech Connect

    Papadimitriou, Vaia; /Fermilab

    2008-04-01

    In this paper we discuss luminosity measurements at Tevatron and HERA as well as plans for luminosity measurements at LHC. We discuss luminosity measurements using the luminosity detectors of the experiments as well as measurements by the machine. We address uncertainties of the measurements, challenges and lessons learned.

  4. Report of Snowmass 2001 working group E2: Electron - positron colliders from the phi to the Z

    SciTech Connect

    Zhen-guo Zhao et al.

    2002-12-23

    We report on the status and plans of experiments now running or proposed for electron-positron colliders at energies between the {phi} and the Z. The e{sup +}e{sup -}B and charm factories we considered were PEP-II/BABAR, KEKB/Belle, superKEK, SuperBABAR, and CESR-c/CLEO-c. We reviewed the programs at the {phi} factory at Frascati and the proposed PEP-N facility at Stanford Linear Accelerator Center. We studied the prospects for B physics with a dedicated linear collider Z factory, associated with the TESLA high energy linear collider. In all cases, we compared the physics reach of these facilities with that of alternative experiments at hadron colliders or fixed target facilities.

  5. Present optics options for TeV colliders

    SciTech Connect

    Spencer, J.E.

    1986-05-01

    A practical approach for implementing TeV collider optics with high luminosities pounds approx. = 10/sup 33/ (cm/sup 2/ s)/sup -1/ but without large pinch effects is given using current alternatives. Characteristics are considered that constrain the optics and the types and orders of magnets required. A modified linac FoDo cell based on permanent magnet hybrid quadrupoles is discussed. Similarly, a demagnifying, permanent magnet telescopic system that allows variation of beta, eta and energy is suggested for the final focus. The basic cell for low emittance damping rings can also be constructed solely from permanent magnets. Small diameter, low permeability, high field permanent magnets have proven useful for injection and extraction lines and are also compatible with the large particle near the interaction regions as well as with exotic experiments for production and use of secondary beams or for multi-bunch coalescing schemes for control of longitudinal bunch distribution. An 8-10 GeV prototype cell and final focus experiment is proposed to verify and study such systems as well as do some interesting physics tests. One example, which could be used with the PEP storage ring, would convert an external electron beam into a photon beam to avoid beamstrahlung effects - a major problem for high energy e+- colliders.

  6. Beam dynamics issues for linear colliders

    SciTech Connect

    Ruth, R.D.

    1987-09-01

    In this paper we discuss various beam dynamics issues for linear colliders. The emphasis is to explore beam dynamics effects which lead to an effective dilution of the emittance of the beam and thus to a loss of luminosity. These considerations lead to various tolerances which are evaluated for a particular parameter set.

  7. Proton-proton colliding beam facility ISABELLE

    SciTech Connect

    Hahn, H

    1980-01-01

    This paper attempts to present the status of the ISABELLE construction project, which has the objective of building a 400 + 400 GeV proton colliding beam facility. The major technical features of the superconducting accelerators with their projected performance are described. Progress made so far, difficulties encountered, and the program until completion in 1986 is briefly reviewed.

  8. Difficult Decisions: The Superconducting Super Collider.

    ERIC Educational Resources Information Center

    Newton, David E.; Slesnick, Irwin L.

    1990-01-01

    The fundamental principles of the superconducting super collider are presented. Arguments for the construction of this apparatus and policy issues surrounding its construction are discussed. Charts of the fundamental atomic particles and forces and the history of particle accelerators are provided. An activity for discussing this controversial…

  9. Cost optimization of a hadron collider

    SciTech Connect

    Vadim V. Kashikhin and Peter J. Limon

    2001-11-30

    This paper discusses cost scaling laws and optimization of hadron colliders based on high field magnets. Using a few simplifying assumptions that should give a reasonable approximation, cost of the magnet is divided among several major components. Scaling law for every component is determined along with the weight factors that allow cost comparison between different magnet designs. Cost of hadron collider as a function of field, aperture size and critical current density in superconductor is described analytically that allows cost optimization by changing magnet parameters. The optimum magnetic field is determined for machines based on NbTi superconductor, operating at 4.2 K or 1.9 K and NB{sub 3}Sn superconductor operating at 4.2 K. Analyzed influence of main magnet design parameters on a machine cost provided information on ways leading to the magnet cost reduction. Economical justification of a NB{sub 3}Sn collider is performed, which lets to determine the maximum price ratio between NB{sub 3}Sn and NbTi superconductors that makes NB{sub 3}Sn collider economically effective.

  10. From the LHC to Future Colliders

    SciTech Connect

    De Roeck, A.; Ellis, J.; Grojean, C.; Heinemeyer, S.; Jakobs, K.; Weiglein, G.; Azuelos, G.; Dawson, S.; Gripaios, B.; Han, T.; Hewett, J.; Lancaster, M.; Mariotti, C.; Moortgat, F.; Moortgat-Pick, G.; Polesello, G.; Riemann, S.; Assamagan, K.; Bechtle, P.; Carena, M.; Chachamis, G.; /more authors..

    2010-06-11

    Discoveries at the LHC will soon set the physics agenda for future colliders. This report of a CERN Theory Institute includes the summaries of Working Groups that reviewed the physics goals and prospects of LHC running with 10 to 300 fb{sup -1} of integrated luminosity, of the proposed sLHC luminosity upgrade, of the ILC, of CLIC, of the LHeC and of a muon collider. The four Working Groups considered possible scenarios for the first 10 fb{sup -1} of data at the LHC in which (i) a state with properties that are compatible with a Higgs boson is discovered, (ii) no such state is discovered either because the Higgs properties are such that it is difficult to detect or because no Higgs boson exists, (iii) a missing-energy signal beyond the Standard Model is discovered as in some supersymmetric models, and (iv) some other exotic signature of new physics is discovered. In the contexts of these scenarios, theWorking Groups reviewed the capabilities of the future colliders to study in more detail whatever new physics may be discovered by the LHC. Their reports provide the particle physics community with some tools for reviewing the scientific priorities for future colliders after the LHC produces its first harvest of new physics from multi-TeV collisions.

  11. Beam-beam issues in asymmetric colliders

    SciTech Connect

    Furman, M.A.

    1992-07-01

    We discuss generic beam-beam issues for proposed asymmetric e{sup +}- e{sup -} colliders. We illustrate the issues by choosing, as examples, the proposals by Cornell University (CESR-B), KEK, and SLAC/LBL/LLNL (PEP-II).

  12. 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…

  13. Towards a Future Linear Collider and The Linear Collider Studies at CERN

    ScienceCinema

    None

    2011-10-06

    During the week 18-22 October, more than 400 physicists will meet at CERN and in the CICG (International Conference Centre Geneva) to review the global progress towards a future linear collider. The 2010 International Workshop on Linear Colliders will study the physics, detectors and accelerator complex of a linear collider covering both the CLIC and ILC options. Among the topics presented and discussed will be the progress towards the CLIC Conceptual Design Report in 2011, the ILC Technical Design Report in 2012, physics and detector studies linked to these reports, and an increasing numbers of common working group activities. The seminar will give an overview of these topics and also CERN?s linear collider studies, focusing on current activities and initial plans for the period 2011-16. n.b: The Council Chamber is also reserved for this colloquium with a live transmission from the Main Auditorium.

  14. The Collider Principle in Causal Reasoning: Why the Monty Hall Dilemma Is So Hard

    ERIC Educational Resources Information Center

    Burns, Bruce D.; Wieth, Mareike

    2004-01-01

    The authors tested the thesis that people find the Monty Hall dilemma (MHD) hard because they fail to understand the implications of its causal structure, a collider structure in which 2 independent causal factors influence a single outcome. In 4 experiments, participants performed better in versions of the MHD involving competition, which…

  15. High Energy Accelerator and Colliding Beam User Group: Progress report, March 1, 1988--February 28, 1989

    SciTech Connect

    Not Available

    1988-09-01

    This report discusses work carried out by the High Energy Accelerator and Colliding Beam User Group at the University of Maryland. Particular topics discussed are: OPAL experiment at LEP; deep inelastic muon interactions; B physics with the CLEO detector at CESR; further results from JADE; and search for ''small'' violation of the Pauli principle. (LSP)

  16. High-brightness injectors for hadron colliders

    SciTech Connect

    Wangler, T.P.

    1990-01-01

    The counterrotating beams in collider rings consist of trains of beam bunches with N{sub B} particles per bunch, spaced a distance S{sub B} apart. When the bunches collide, the interaction rate is determined by the luminosity, which is defined as the interaction rate per unit cross section. For head-on collisions between cylindrical Gaussian beams moving at speed {beta}c, the luminosity is given by L = N{sub B}{sup 2}{beta}c/4{pi}{sigma}{sup 2}S{sub B}, where {sigma} is the rms beam size projected onto a transverse plane (the two transverse planes are assumed identical) at the interaction point. This beam size depends on the rms emittance of the beam and the focusing strength, which is a measure of the 2-D phase-space area in each transverse plane, and is defined in terms of the second moments of the beam distribution. Our convention is to use the rms normalized emittance, without factors of 4 or 6 that are sometimes used. The quantity {tilde {beta}} is the Courant-Synder betatron amplitude function at the interaction point, a characteristic of the focusing lattice and {gamma} is the relativistic Lorentz factor. Achieving high luminosity at a given energy, and at practical values of {tilde {beta}} and S{sub B}, requires a large value for the ratio N{sub B}{sup 2}/{var epsilon}{sub n}, which implies high intensity and small emittance. Thus, specification of the luminosity sets the requirements for beam intensity and emittance, and establishes the requirements on the performance of the injector to the collider ring. In general, for fixed N{sub B}, the luminosity can be increased if {var epsilon}{sub n} can be reduced. The minimum emittance of the collider is limited by the performance of the injector; consequently the design of the injector is of great importance for the ultimate performance of the collider.

  17. Current Experiments in Particle Physics (September 1996)

    SciTech Connect

    Galic, H.; Lehar, F.; Klyukhin, V.I.; Ryabov, Yu.G.; Bilak, S.V.; Illarionova, N.S.; Khachaturov, B.A.; Strokovsky, E.A.; Hoffman, C.M.; Kettle, P.-R.; Olin, A.; Armstrong, F.E.

    1996-09-01

    This report contains summaries of current and recent experiments in Particle Physics. Included are experiments at BEPC (Beijing), BNL, CEBAF, CERN, CESR, DESY, FNAL, Frascati, ITEP (Moscow), JINR (Dubna), KEK, LAMPF, Novosibirsk, PNPI (St. Petersburg), PSI, Saclay, Serpukhov, SLAC, and TRIUMF, and also several proton decay and solar neutrino experiments. Excluded are experiments that finished taking data before 1991. Instructions are given for the World Wide Web (WWW) searching of the computer database (maintained under the SLAC-SPIRES system) that contains the summaries. This report contains full summaries of 180 approved current and recent experiments in elementary particle physics. The focus of the report is on selected experiments which directly contribute to our better understanding of elementary particles and their properties such as masses, widths or lifetimes, and branching fractions.

  18. Department of Energy assessment of the Large Hadron Collider

    SciTech Connect

    1996-06-01

    This report summarizes the conclusions of the committee that assessed the cost estimate for the Large Hadron Collider (LHC). This proton-proton collider will be built at CERN, the European Laboratory for Particle Physics near Geneva, Switzerland. The committee found the accelerator-project cost estimate of 2.3 billion in 1995 Swiss francs, or about $2 billion US, to be adequate and reasonable. The planned project completion date of 2005 also appears achievable, assuming the resources are available when needed. The cost estimate was made using established European accounting procedures. In particular, the cost estimate does not include R and D, prototyping and testing, spare parts, and most of the engineering labor. Also excluded are costs for decommissioning the Large Electron-Positron collider (LEP) that now occupies the tunnel, modifications to the injector system, the experimental areas, preoperations costs, and CERN manpower. All these items are assumed by CERN to be included in the normal annual operations budget rather than the construction budget. Finally, contingency is built into the base estimate, in contrast to Department of Energy (DOE) estimates that explicitly identify contingency. The committee`s charge, given by Dr. James F. Decker, Deputy Directory of the DOE Office of Energy Research, was to understand the basis for the LHC cost estimate, identify uncertainties, and judge the overall validity of the estimate, proposed schedule, and related issues. The committee met at CERN April 22--26, 1996. The assessment was based on the October 1995 LHC Conceptual Design Report or ``Yellow Book,`` cost estimates and formal presentations made by the CERN staff, site inspection, detailed discussions with LHC technical experts, and the committee members` considerable experience.

  19. Compilation of current high-energy-physics experiments

    SciTech Connect

    Wohl, C.G.; Kelly, R.L.; Armstrong, F.E.

    1980-04-01

    This is the third edition of a compilation of current high energy physics experiments. It is a collaborative effort of the Berkeley Particle Data Group, the SLAC library, and ten participating laboratories: Argonne (ANL), Brookhaven (BNL), CERN, DESY, Fermilab (FNAL), the Institute for Nuclear Study, Tokyo (INS), KEK, Rutherford (RHEL), Serpukhov (SERP), and SLAC. The compilation includes summaries of all high energy physics experiments at the above laboratories that (1) were approved (and not subsequently withdrawn) before about January 1980, and (2) had not completed taking of data by 1 January 1976.

  20. Collider Detector at Fermilab (CDF): Data from the Top Group's Top Quark Research

    DOE Data Explorer

    The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Top group studies the properties of the top quark, the heaviest known fundamental particle. Their public web page makes data and numerous figures available from both CDF Runs I and II.

  1. Collider Detector at Fermilab (CDF): Data from Supersymmetry, New Phenomena Research of the CDF Exotics Group

    DOE Data Explorer

    The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Exotics group searches for Supersymmetry and other New Phenomena. Their public web page makes data and numerous figures available from both CDF Runs I and II.

  2. Higgs bosons, electroweak symmetry breaking, and the physics of the Large Hadron Collider

    SciTech Connect

    Quigg, Chris; /Fermilab /CERN

    2007-02-01

    The Large Hadron Collider, a 7 {circle_plus} 7 TeV proton-proton collider under construction at CERN (the European Laboratory for Particle Physics in Geneva), will take experiments squarely into a new energy domain where mysteries of the electroweak interaction will be unveiled. What marks the 1-TeV scale as an important target? Why is understanding how the electroweak symmetry is hidden important to our conception of the world around us? What expectations do we have for the agent that hides the electroweak symmetry? Why do particle physicists anticipate a great harvest of discoveries within reach of the LHC?

  3. An Afterburner at the ILC: The Collider Viewpoint

    SciTech Connect

    Raubenheimer, Tor O.

    2004-12-07

    The concept of a high-gradient plasma wakefield accelerator is considered as an upgrade path for the International Linear Collider, a future linear collider. Basic parameters are presented based on those developed for the SLC 'Afterburner'. Basic layout considerations are described and the primary concerns related to the collider operation are discussed.

  4. An Afterburner at the ILC: The Collider Viewpoint

    SciTech Connect

    Raubenheimer, T

    2004-09-01

    The concept of a high-gradient plasma wakefield accelerator is considered as an upgrade path for the International Linear Collider, a future linear collider. Basic parameters are presented based on those developed for the SLC ''Afterburner.'' Basic layout considerations are described and the primary concerns related to the collider operation are discussed.

  5. Higgs boson and Z physics at the first muon collider

    SciTech Connect

    Demarteau, M.; Han, T.

    1998-01-01

    The potential for the Higgs boson and Z-pole physics at the first muon collider is summarized, based on the discussions at the ``Workshop on the Physics at the First Muon Collider and at the Front End of a Muon Collider``.

  6. LASER-PLASMA-ACCELERATOR-BASED GAMMA GAMMA COLLIDERS

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Toth, Cs.; Geddes, C. G. R.; Leemans, W. P.

    2009-05-04

    Design considerations for a next-generation linear collider based on laser-plasma-accelerators are discussed, and a laser-plasma-accelerator-based gamma-gamma collider is considered. An example of the parameters for a 0.5 TeV laser-plasma-accelerator gamma gamma collider is presented.

  7. Laser triggered injection of electrons in a laser wakefield accelerator with the colliding pulse method

    SciTech Connect

    Nakamura, K.; Fubiani, G.; Geddes, C.G.R.; Michel, P.; van Tilborg, J.; Toth, C.; Esarey, E.; Schroeder, C.B.; Leemans, W.P.

    2004-10-22

    An injection scheme for a laser wakefield accelerator that employs a counter propagating laser (colliding with the drive laser pulse, used to generate a plasma wake) is discussed. The threshold laser intensity for electron injection into the wakefield was analyzed using a heuristic model based on phase-space island overlap. Analysis shows that the injection can be performed using modest counter propagating laser intensity a{sub 1} < 0.5 for a drive laser intensity of a{sub 0} = 1.0. Preliminary experiments were preformed using a drive beam and colliding beam. Charge enhancement by the colliding pulse was observed. Increasing the signal-to-noise ratio by means of a preformed plasma channel is discussed.

  8. J. J. Sakurai Prize for Theoretical Particle Physics Talk: Collider Physics: Yesterday, Today and Tomorrow

    NASA Astrophysics Data System (ADS)

    Eichten, Estia

    2011-04-01

    More than a quarter century ago, theoretical issues with the Standard Model scalar boson sector inspired theorists to develop alternative models of electroweak symmetry breaking. The goal of the EHLQ study of hadron collider physics was to help determine the basic parameters of a supercollider that could distinguish these alternatives. Now we await data from the CMS and ATLAS experiments at CERN's Large Hadron Collider to solve this mystery. Does the Standard Model survive or, as theorists generally expect, does new physics appear (Strong Dynamics, SUSY, Extra Dimensions,...)? Even well into the LHC era it is likely that questions about the origin of fermion mass and mixings will remain and new physics will bring new puzzles. This time, the associated new scales are unknown. The opportunity to address new physics at a future multi-TeV lepton collider is briefly addressed.

  9. A photon-photon collider in a vacuum hohlraum

    NASA Astrophysics Data System (ADS)

    Pike, O. J.; Mackenroth, F.; Hill, E. G.; Rose, S. J.

    2014-06-01

    The ability to create matter from light is amongst the most striking predictions of quantum electrodynamics. Experimental signatures of this have been reported in the scattering of ultra-relativistic electron beams with laser beams, intense laser-plasma interactions and laser-driven solid target scattering. However, all such routes involve massive particles. The simplest mechanism by which pure light can be transformed into matter, Breit-Wheeler pair production (γγ' --> e+e-), has never been observed in the laboratory. Here, we present the design of a new class of photon-photon collider in which a gamma-ray beam is fired into the high-temperature radiation field of a laser-heated hohlraum. Matching experimental parameters to current-generation facilities, Monte Carlo simulations suggest that this scheme is capable of producing of the order of 105 Breit-Wheeler pairs in a single shot. This would provide the first realization of a pure photon-photon collider, representing the advent of a new type of high-energy physics experiment.

  10. The Electroweak Phase Transition: Corralling the Higgs with Colliders & Cosmology

    NASA Astrophysics Data System (ADS)

    Long, Andrew J.

    Through this thesis, I investigate the way in which the electroweak phase transition, and therefore the Higgs boson, bridges high energy particle physics and early universe cosmology; moreover, I argue that it is particularly interesting to explore this bridge today as experiments such as the Large Hadron Collider begin to uncover the nature of physics at the electroweak scale. I will discuss how measurements of the properties of the Higgs boson at the Large Hadron Collider allow one to determine the nature of the phase transition that was responsible for electroweak symmetry breaking in the early universe. That information in turn will allow one to assess whether the asymmetry between the abundances of matter and anti-matter in the universe may have been generated during the electroweak phase transition. Additionally, I will discuss the impact of the electroweak phase transition on another cosmological relic: namely, the dark matter. Precise measurements of the mass and abundance of dark matter today yield further information about the nature of the electroweak phase transition, in some scenarios. This information may be used to test the hypothesis that the cosmological constant, assumed to be a good model of dark energy, is finely tuned. In this way, I hope to demonstrate the importance of the electroweak phase transition as a bridge between terrestrial tests of high energy physics and cosmological tests of the physics of the early universe.

  11. TARGETRY FOR A MU+MU- COLLIDER.

    SciTech Connect

    KIRK,H.G.

    1999-03-29

    The requirement for high luminosity in a {mu}{sup +}{mu}{sup -} collider leads one to conclude that a prodigious source of pions is needed followed by an efficient capture/decay channel. Significant targetry issues are raised by these demands. Among these are (1) the best target configuration to tolerate a high-rep rate, high-power proton beam ({approx} 10{sup 14} ppp at 15 Hz), (2) the pion spectra of the produced pions and (3) the best configuration for maximizing the quantity of captured pions. In this paper, the current thinking of the {mu}{sup +}{mu}{sup -} collider collaboration for solutions to these issues is discussed. In addition, we give a description of the R&D program designed to provide a proof-of-principle for a muon capture system capable of meeting the demands of a future high-luminosity machine.

  12. Global QCD Analysis and Hadron Collider Physics

    SciTech Connect

    Tung, W.-K.

    2005-03-22

    The role of global QCD analysis of parton distribution functions (PDFs) in collider physics at the Tevatron and LHC is surveyed. Current status of PDF analyses are reviewed, emphasizing the uncertainties and the open issues. The stability of NLO QCD global analysis and its prediction on 'standard candle' W/Z cross sections at hadron colliders are discussed. The importance of the precise measurement of various W/Z cross sections at the Tevatron in advancing our knowledge of PDFs, hence in enhancing the capabilities of making significant progress in W mass and top quark parameter measurements, as well as the discovery potentials of Higgs and New Physics at the Tevatron and LHC, is emphasized.

  13. Future high energy colliders symposium. Summary report

    SciTech Connect

    Parsa, Z. |

    1996-12-31

    A `Future High Energy Colliders` Symposium was held October 21-25, 1996 at the Institute for Theoretical Physics (ITP) in Santa Barbara. This was one of the 3 symposia hosted by the ITP and supported by its sponsor, the National Science Foundation, as part of a 5 month program on `New Ideas for Particle Accelerators`. The long term program and symposia were organized and coordinated by Dr. Zohreh Parsa of Brookhaven National Laboratory/ITP. The purpose of the symposium was to discuss the future direction of high energy physics by bringing together leaders from the theoretical, experimental and accelerator physics communities. Their talks provided personal perspectives on the physics objectives and the technology demands of future high energy colliders. Collectively, they formed a vision for where the field should be heading and how it might best reach its objectives.

  14. Initial operation of the Tevatron collider

    SciTech Connect

    Johnson, R.

    1987-03-01

    The Tevatron is now the highest energy proton synchrotron and the only accelerator made with superconducting magnets. Operating since 1983 as a fixed-target machine at energies up to 800 GeV, it has now been modified to operate as a 900 GeV antiproton-proton collider. This paper describes the initial operation of the machine in this mode. The new features of the Fermilab complex, including the antiproton source and the Main Ring injector with its two overpasses and new rf requirements, are discussed. Beam characteristics in the Tevatron (including lifetimes, emittances, luminosity, beam-beam tune shifts, backgrounds, and low beta complications), the coordination of the steps in the accelerator chain, and the commissioning history are also discussed. Finally, some plans for the improvement of the collider are presented.

  15. Reverse Emittance Exchange for Muon Colliders

    SciTech Connect

    V. Ivanov, A. Afanasev, C.M. Ankenbrandt, R.P. Johnson, G.M. Wang, S.A. Bogacz, Y.S. Derbenev

    2009-05-01

    Muon collider luminosity depends on the number of muons in the storage ring and on the transverse size of the beams in collision. Ionization cooling as it is currently envisioned will not cool the beam sizes sufficiently well to provide adequate luminosity without large muon intensities. Six-dimensional cooling schemes will reduce the longitudinal emittance of a muon beam so that smaller high frequency RF cavities can be used for later stages of cooling and for acceleration. However, the bunch length at collision energy is then shorter than needed to match the interaction region beta function. New ideas to shrink transverse beam dimensions by lengthening each bunch will help achieve high luminosity in muon colliders. Analytic expressions for the reverse emittance exchange mechanism were derived, including a new resonant method of beam focusing.

  16. Collider Detector (CDF) at FERMILAB: an overview

    SciTech Connect

    Theriot, D.

    1984-07-01

    CDF, the Collider Detector at Fermilab, is a collaboration of almost 150 physicists from ten US universities (University of Chicago, Brandeis University, Harvard University, University of Illinois, University of Pennsylvania, Purdue University, Rockefeller University, Rutgers University, Texas A and M University, and University of Wisconsin), three US DOE supported national laboratories (Fermilab, Argonne National Laboratory, and Lawrence Berkeley Laboratory), Italy (Frascati Laboratory and University of Pisa), and Japan (KEK National Laboratory and Unversity of Tsukuba). The primary physics goal for CDF is to study the general features of proton-antiproton collisions at 2 TeV center-of-mass energy. On general grounds, we expect that parton subenergies in the range 50 to 500 GeV will provide the most interesting physics at this energy. Work at the present CERN Collider has already demonstrated the richness of the 100 GeV scale in parton subenergies.

  17. 1987 DOE review: First collider run operation

    SciTech Connect

    Childress, S.; Crawford, J.; Dugan, G.; Edwards, H.; Finley, D.A.; Fowler, W.B.; Harrison, M.; Holmes, S.; Makara, J.N.; Malamud, E.

    1987-05-01

    This review covers the operations of the first run of the 1.8 TeV superconducting super collider. The papers enclosed cover: PBAR source status, fixed target operation, Tevatron cryogenic reliability and capacity upgrade, Tevatron Energy upgrade progress and plans, status of the D0 low beta insertion, 1.8 K and 4.7 K refrigeration for low-..beta.. quadrupoles, progress and plans for the LINAC and booster, near term and long term and long term performance improvements.

  18. Polarized muon beams for muon collider

    NASA Astrophysics Data System (ADS)

    Skrinsky, A. N.

    1996-11-01

    An option for the production of intense and highly polarized muon beams, suitable for a high-luminosity muon collider, is described briefly. It is based on a multi-channel pion-collection system, narrow-band pion-to-muon decay channels, proper muon spin gymnastics, and ionization cooling to combine all of the muon beams into a single bunch of ultimately low emittance.

  19. ψψ production at collider energies

    NASA Astrophysics Data System (ADS)

    Humpert, B.; Méry, P.

    1983-03-01

    We estimate ψψ production at collider energies in the framework of perturbative QCD. The O(α{/s 2})-(α{/s 4}) parton cross-sections, with the non-relativistic approximation for the heavy quark bound states, are used. This first insight into the characteristics of the kinematical distributions allows predictions on the predominance of the quark, gluon or B meson production mechanisms in particular kinematical regions.

  20. Progress report on the SLAC Linear Collider

    SciTech Connect

    Rees, J.

    1986-06-01

    The SLAC Linear Collider project (SLC) is reported as being near completion. The performance specifications are tabulated both for the initial form and for eventual goals. Various parts of the SLC are described and the status of their construction is reported, including the front end electron gun and booster, the linac, damping ring, positron source, SLC arcs, and conventional facilities. 5 refs., 12 figs. (LEW)

  1. 2009: A Colliding-Wind Odyssey

    NASA Astrophysics Data System (ADS)

    Fahed, R.; Moffat, A. F. J.; Zorec, J.; Eversberg, T.; Chené, A. N.; Alves, F.; Arnold, W.; Bergmann, T.; Corcoran, M. F.; Correia Viegas, N. G.; Dougherty, S. M.; Fernando, A.; Frémat, Y.; Gouveia Carreira, L. F.; Hunger, T.; Knapen, J. H.; Leadbeater, R.; Marques Dias, F.; Martayan, C.; Morel, T.; Pittard, J. M.; Pollock, A. M. T.; Rauw, G.; Reinecke, N.; Ribeiro, J.; Romeo, N.; Sánchez-Gallego, J. R.; dos Santos, E. M.; Schanne, L.; Stahl, O.; Stober, Ba.; Stober, Be.; Vollmann, K.; Williams, P. M.

    2012-12-01

    We present the results from two optical spectroscopic campaigns on colliding-wind binaries (CWB) which both occurred in 2009. The first one was on WR 140 (WC7pd + O5.5fc), the archetype of CWB, which experienced periastron passage of its highly elliptical 8-year orbit in January. The WR 140 campaign consisted of a unique and constructive collaboration between amateur and professional astronomers and took place at half a dozen locations, including Teide Observatory, Observatoire de Haute Provence, Dominion Astrophysical Observatory, Observatoire du Mont-Mégantic and at several small private observatories. The second campaign was on a selection of 5 short-period WR + O binaries not yet studied for colliding-wind effects: WR 12 (WN8h), WR 21 (WN5o + O7 V), WR 30 (WC6 + O7.5 V), WR 31 (WN4o + O8), and WR 47 (WN6o + O5). The campaign took place at Leoncito Observatory, Argentina, during 1 month. We provide updated values of most of these systems for the orbital parameters, new estimates for the WR and O star masses and new constraints on the mass-loss rates and colliding wind geometry.

  2. Muon Collider Machine-Detector Interface

    SciTech Connect

    Mokhov, Nikolai V.; /Fermilab

    2011-08-01

    In order to realize the high physics potential of a Muon Collider (MC) a high luminosity of {mu}{sup +}{mu}{sup -}-collisions at the Interaction Point (IP) in the TeV range must be achieved ({approx}10{sup 34} cm{sup -2}s{sup -1}). To reach this goal, a number of demanding requirements on the collider optics and the IR hardware - arising from the short muon lifetime and from relatively large values of the transverse emittance and momentum spread in muon beams that can realistically be obtained with ionization cooling should be satisfied. These requirements are aggravated by limitations on the quadrupole gradients as well as by the necessity to protect superconducting magnets and collider detectors from muon decay products. The overall detector performance in this domain is strongly dependent on the background particle rates in various sub-detectors. The deleterious effects of the background and radiation environment produced by the beam in the ring are very important issues in the Interaction Region (IR), detector and Machine-Detector Interface (MDI) designs. This report is based on studies presented very recently.

  3. Structure and Dynamics of Colliding Plasma Jets

    DOE PAGESBeta

    Li, C.; Ryutov, D.; Hu, S.; Rosenberg, M.; Zylstra, A.; Seguin, F.; Frenje, J.; Casey, D.; Gatu Johnson, M.; Manuel, M.; et al

    2013-12-01

    Monoenergetic-proton radiographs of laser-generated, high-Mach-number plasma jets colliding at various angles shed light on the structures and dynamics of these collisions. The observations compare favorably with results from 2D hydrodynamic simulations of multistream plasma jets, and also with results from an analytic treatment of electron flow and magnetic field advection. In collisions of two noncollinear jets, the observed flow structure is similar to the analytic model’s prediction of a characteristic feature with a narrow structure pointing in one direction and a much thicker one pointing in the opposite direction. Spontaneous magnetic fields, largely azimuthal around the colliding jets and generatedmore » by the well-known ∇Te ×∇ne Biermann battery effect near the periphery of the laser spots, are demonstrated to be “frozen in” the plasma (due to high magnetic Reynolds number RM ~5×10⁴) and advected along the jet streamlines of the electron flow. These studies provide novel insight into the interactions and dynamics of colliding plasma jets.« less

  4. The Relativistic Heavy Ion Collider at Brookhaven

    SciTech Connect

    Hahn, H.

    1988-01-01

    The conceptual design of a Relativistic Heavy Ion Collider (RACK) to be constructed in the existing 3.8 km tunnel at Brookhaven has been developed. The collider has been designed to provide collisions of gold ions at six intersection points with a luminosity of about 5 /times/ 10/sup 26/cm/sup /minus/2/sec/sup /minus/1/ at an energy of 100 GeV/u in each beam. Collisions with different ion species, including protons, will be possible. The collider consists of two interlaced, but otherwise separate, superconducting magnet rings. The 9.7 m long dipoles will operate at 3.5 T. Their 8 cm aperture was determined by the dimensions of gold ion beams taking into account diffusion due to intrabeam scattering. Heavy ion beams will be available from the Tandem Van de Graaff/Booster/AGS complex. The salient design features and the reasons for major design choices of the proposed machine are discussed in this paper. 24 refs., 7 figs., 2 tabs.

  5. Linear collider IR and final focus introduction

    SciTech Connect

    Irwin, J.; Burke, D.

    1991-09-01

    The Linear Collider subgroup of the Accelerator Physics working group concerned itself with all aspects of the Next Linear Collider (NLC) design from the end of the accelerating structure to and through the interaction region. Within this region are: (1) a collimation section, (2) muon protection (of the detector from the collimator), (3) final focus system, (4) interaction point physics, and (5) detector masking from synchrotron radiation and beam-beam pair production. These areas of study are indicated schematically in Fig. 1. The parameters for the Next Linear Collider are still in motion, but attention has settled on a handful of parameter sets. Energies under consideration vary from 0.5 to 1.5 TeV in the center of mass, and luminosities vary from 10{sup 33} to 10{sup 34} cm{sup {minus}2}s{sup {minus}1}. To be concrete we chose as a guide for our studies the parameter sets labeled F and G, Table 1 from Palmer. These cover large and small crossing angle cases and 0.4 m to 1.8 m of free length at the interaction point.

  6. Structure and Dynamics of Colliding Plasma Jets

    SciTech Connect

    Li, C.; Ryutov, D.; Hu, S.; Rosenberg, M.; Zylstra, A.; Seguin, F.; Frenje, J.; Casey, D.; Gatu Johnson, M.; Manuel, M.; Rinderknecht, H.; Petrasso, R.; Amendt, P.; Park, H.; Remington, B.; Wilks, S.; Betti, R.; Froula, D.; Knauer, J.; Meyerhofer, D.; Drake, R.; Kuranz, C.; Young, R.; Koenig, M.

    2013-12-01

    Monoenergetic-proton radiographs of laser-generated, high-Mach-number plasma jets colliding at various angles shed light on the structures and dynamics of these collisions. The observations compare favorably with results from 2D hydrodynamic simulations of multistream plasma jets, and also with results from an analytic treatment of electron flow and magnetic field advection. In collisions of two noncollinear jets, the observed flow structure is similar to the analytic model’s prediction of a characteristic feature with a narrow structure pointing in one direction and a much thicker one pointing in the opposite direction. Spontaneous magnetic fields, largely azimuthal around the colliding jets and generated by the well-known ∇Te ×∇ne Biermann battery effect near the periphery of the laser spots, are demonstrated to be “frozen in” the plasma (due to high magnetic Reynolds number RM ~5×10⁴) and advected along the jet streamlines of the electron flow. These studies provide novel insight into the interactions and dynamics of colliding plasma jets.

  7. Neutrino Factory and Muon Collider Fellow

    SciTech Connect

    Hanson, Gail G.; Snopak, Pavel; Bao, Yu

    2015-03-20

    Muons are fundamental particles like electrons but much more massive. Muon accelerators can provide physics opportunities similar to those of electron accelerators, but because of the larger mass muons lose less energy to radiation, allowing more compact facilities with lower operating costs. The way muon beams are produced makes them too large to fit into the vacuum chamber of a cost-effective accelerator, and the short muon lifetime means that the beams must be reduced in size rather quickly, without losing too many of the muons. This reduction in size is called "cooling." Ionization cooling is a new technique that can accomplish such cooling. Intense muon beams can then be accelerated and injected into a storage ring, where they can be used to produce neutrino beams through their decays or collided with muons of the opposite charge to produce a muon collider, similar to an electron-positron collider. We report on the research carried out at the University of California, Riverside, towards producing such muon accelerators, as part of the Muon Accelerator Program based at Fermilab. Since this research was carried out in a university environment, we were able to involve both undergraduate and graduate students.

  8. Interpenetration and stagnation in colliding laser plasmas

    SciTech Connect

    Al-Shboul, K. F.; Harilal, S. S. Hassan, S. M.; Hassanein, A.; Costello, J. T.; Yabuuchi, T.; Tanaka, K. A.; Hirooka, Y.

    2014-01-15

    We have investigated plasma stagnation and interaction effects in colliding laser-produced plasmas. For generating colliding plasmas, two split laser beams were line-focused onto a hemi-circular target and the seed plasmas so produced were allowed to expand in mutually orthogonal directions. This experimental setup forced the expanding seed plasmas to come to a focus at the center of the chamber. The interpenetration and stagnation of plasmas of candidate fusion wall materials, viz., carbon and tungsten, and other materials, viz., aluminum, and molybdenum were investigated in this study. Fast-gated imaging, Faraday cup ion analysis, and optical emission spectroscopy were used for diagnosing seed and colliding plasma plumes. Our results show that high-Z target (W, Mo) plasma ions interpenetrate each other, while low-Z (C, Al) plasmas stagnate at the collision plane. For carbon seed plasmas, an intense stagnation was observed resulting in longer plasma lifetime; in addition, the stagnation layer was found to be rich with C{sub 2} dimers.

  9. Measurement of Boer-Mulders Function via Drell-Yan Process by SeaQuest Experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Nakano, Kenichi

    2016-02-01

    The SeaQuest experiment is being carried out at Fermi National Accelerator Lab (FNAL) to investigate the nucleon structure with the Drell-Yan process. It utilizes the 120-GeV proton beam extracted from the FNAL Main Injector and targets of liquid hydrogen, liquid deuterium, carbon, iron and tungsten. The solid targets are used to measure the nuclear effects. This paper describes the flavor asymmetry of light anti-quark distributions in the proton (d¯/ū) and the angular distribution of Drell-Yan process. The Boer-Mulders function (h1⊥(x,k T)) can be derived from the size (ν) of cos 2ϕ modulation. SeaQuest finished the second data-taking period in August 2014. Preliminary results of d¯/ū and ν are reported.

  10. Probing neutrino oscillations in supersymmetric models at the Large Hadron Collider

    SciTech Connect

    Campos, F. de; Eboli, O. J. P.; Hirsch, M.; Valle, J. W. F.; Porod, W.

    2010-10-01

    The lightest supersymmetric particle may decay with branching ratios that correlate with neutrino oscillation parameters. In this case the CERN Large Hadron Collider (LHC) has the potential to probe the atmospheric neutrino mixing angle with sensitivity competitive to its low-energy determination by underground experiments. Under realistic detection assumptions, we identify the necessary conditions for the experiments at CERN's LHC to probe the simplest scenario for neutrino masses induced by minimal supergravity with bilinear R parity violation.

  11. Indiana University High Energy Physics, Task A. Technical progress report, 1992--1993

    SciTech Connect

    Brabson, B.; Crittenden, R.; Dzierba, A.

    1993-10-01

    This report discusses research at Indians University on the following high energy physics experiments: A search for mesons with unusual quantum numbers; hadronic states produced in association with high-mass dimuons; FNAL E740 (D0); superconducting super collider; and OPAL experiment at CERN.

  12. Jet Reconstruction and Spectroscopy at Hadron Colliders

    NASA Astrophysics Data System (ADS)

    Bellettini, Giorgio

    2011-11-01

    Dear colleagues and friends, Major new particle discoveries were made in the past by exploring the mass spectrum of lepton pairs. These searches still have great potential. However, new particle searches are now being extended to masses larger than the W, Z mass. More and more decay channels open up and the branching ratios into lepton pairs are reduced. Also, physics may dictate that states with heavy bosons and quarks become dominant. Examples are the decay of top quarks, and the expected final states of the standard model Higgs boson. Supersymmetry in any of its wide spectrum of models predicts intrigued final states where jets are major observables. To reconstruct masses and to study the dynamics of these states one must exploit the energy-momentum four-vectors of jets. Past experiments at the CERN SPS collider, at HERA, at LEP and now at the Tevatron collider and at LHC, have studied how best to reconstruct hadron jets. However, originally the role of jets in searching for new physics was primarily to sense new parton contact interactions by means of increased large pt tails in inclusive jet spectra, or studying jet events with large missing Et, or measuring branching ratios into jets of different flavour. These studies did not require as accurate a measure of jet four-momenta as needed in new particle searches in multi-jets final states. Figure 1 Figure 1. W, Z associated production in CDF events with large Et, miss and 2 jets. Consider for example (figure 1) the mass spectrum of dijets in events with large missing Et recently measured by CDF [1]. Trigger and analysis cuts were chosen so as to favour production of heavy boson pairs, with decay of one Z boson into neutrinos tagging the event and another W or Z boson decaying into jets. Associated production of boson pairs is observed, but the dijet mass resolution does not allow the separation of W from Z. A broad agreement of the overall observed rate with expectation is found, but a comparative study of the

  13. Search for New Fermions (''Quirks'') at the Fermilab Tevatron Collider

    SciTech Connect

    Abazov, V. M.; Alexeev, G. D.; Golovanov, G.; Kharzheev, Y. N.; Malyshev, V. L.; Tokmenin, V. V.; Vertogradov, L. S.; Yatsunenko, Y. A.; Abbott, B.; Gutierrez, P.; Hossain, S.; Severini, H.; Skubic, P.; Strauss, M.; Abolins, M.; Benitez, J. A.; Brock, R.; Edmunds, D.; Fisher, W.; Kraus, J.

    2010-11-19

    We report results of a search for particles with anomalously high ionization in events with a high transverse energy jet and large missing transverse energy in 2.4 fb{sup -1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron pp collider. Production of such particles (quirks) is expected in scenarios with extra QCD-like SU(N) sectors, and this study is the first dedicated search for such signatures. We find no evidence of a signal and set a lower mass limit of 107, 119, and 133 GeV for the mass of a charged quirk with strong dynamics scale {Lambda} in the range from 10 keV to 1 MeV and N=2, 3, and 5, respectively.

  14. Dark Matter and Collider Physics in Split-UED

    SciTech Connect

    Chan Park, Seong; Shu Jing

    2010-02-10

    Kaluza-Klein dark matter is an attractive weakly interacting massive particle in universal extra dimension model. In the recent extension 'split-UED', annihilation of Kaluza-Klein dark matter with a mass range 600-1000 GeV provides excellent fits to the recently observed excesses in cosmic electron and positron fluxes of Pamela, ATIC and Fermi-LAT experiments. The cosmic gamma-ray flux in the same process can be significant around 300 GeV, thus can be observed or constrained by the forthcoming Fermi-LAT diffuse gamma-ray data. The collider signal at the LHC is the resonance in the dijets channels and the large missing energy in the missing energy plus jets.

  15. Search for New Fermions (``Quirks'') at the Fermilab Tevatron Collider

    NASA Astrophysics Data System (ADS)

    Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T.; Alexeev, G. D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G. A.; Ancu, L. S.; Aoki, M.; Arnoud, Y.; Arov, M.; Askew, A.; Åsman, B.; Atramentov, O.; Avila, C.; Backusmayes, J.; Badaud, F.; Bagby, L.; Baldin, B.; Bandurin, D. V.; Banerjee, S.; Barberis, E.; Baringer, P.; Barreto, J.; Bartlett, J. F.; Bassler, U.; Beale, S.; Bean, A.; Begalli, M.; Begel, M.; Belanger-Champagne, C.; Bellantoni, L.; Benitez, J. A.; Beri, S. B.; Bernardi, G.; Bernhard, R.; Bertram, I.; Besançon, M.; Beuselinck, R.; Bezzubov, V. A.; Bhat, P. C.; Bhatnagar, V.; Blazey, G.; Blessing, S.; Bloom, K.; Boehnlein, A.; Boline, D.; Bolton, T. A.; Boos, E. E.; Borissov, G.; Bose, T.; Brandt, A.; Brandt, O.; Brock, R.; Brooijmans, G.; Bross, A.; Brown, D.; Brown, J.; Bu, X. B.; Buchholz, D.; Buehler, M.; Buescher, V.; Bunichev, V.; Burdin, S.; Burnett, T. H.; Buszello, C. P.; Calpas, B.; Calvet, S.; Camacho-Pérez, E.; Carrasco-Lizarraga, M. A.; Carrera, E.; Casey, B. C. K.; Castilla-Valdez, H.; Chakrabarti, S.; Chakraborty, D.; Chan, K. M.; Chandra, A.; Chen, G.; Chevalier-Théry, S.; Cho, D. K.; Cho, S. W.; Choi, S.; Choudhary, B.; Christoudias, T.; Cihangir, S.; Claes, D.; Clutter, J.; Cooke, M.; Cooper, W. E.; Corcoran, M.; Couderc, F.; Cousinou, M.-C.; Croc, A.; Cutts, D.; Ćwiok, M.; Das, A.; Davies, G.; de, K.; de Jong, S. J.; de La Cruz-Burelo, E.; Déliot, F.; Demarteau, M.; Demina, R.; Denisov, D.; Denisov, S. P.; Desai, S.; Devaughan, K.; Diehl, H. T.; Diesburg, M.; Dominguez, A.; Dorland, T.; Dubey, A.; Dudko, L. V.; Duggan, D.; Duperrin, A.; Dutt, S.; Dyshkant, A.; Eads, M.; Edmunds, D.; Ellison, J.; Elvira, V. D.; Enari, Y.; Eno, S.; Evans, H.; Evans, J. A.; Evdokimov, A.; Evdokimov, V. N.; Facini, G.; Ferapontov, A. V.; Ferbel, T.; Fiedler, F.; Filthaut, F.; Fisher, W.; Fisk, H. E.; Fortner, M.; Fox, H.; Fuess, S.; Gadfort, T.; Garcia-Bellido, A.; Gavrilov, V.; Gay, P.; Geist, W.; Geng, W.; Gerbaudo, D.; Gerber, C. E.; Gershtein, Y.; Ginther, G.; Golovanov, G.; Goussiou, A.; Grannis, P. D.; Greder, S.; Greenlee, H.; Greenwood, Z. D.; Gregores, E. M.; Grenier, G.; Gris, Ph.; Grivaz, J.-F.; Grohsjean, A.; Grünendahl, S.; Grünewald, M. W.; Guo, F.; Guo, J.; Gutierrez, G.; Gutierrez, P.; Haas, A.; Hagopian, S.; Haley, J.; Han, L.; Harder, K.; Harel, A.; Hauptman, J. M.; Hays, J.; Hebbeker, T.; Hedin, D.; Hegab, H.; Heinson, A. P.; Heintz, U.; Hensel, C.; Heredia-de La Cruz, I.; Herner, K.; Hesketh, G.; Hildreth, M. D.; Hirosky, R.; Hoang, T.; Hobbs, J. D.; Hoeneisen, B.; Hohlfeld, M.; Hossain, S.; Hubacek, Z.; Huske, N.; Hynek, V.; Iashvili, I.; Illingworth, R.; Ito, A. S.; Jabeen, S.; Jaffré, M.; Jain, S.; Jamin, D.; Jesik, R.; Johns, K.; Johnson, M.; Johnston, D.; Jonckheere, A.; Jonsson, P.; Joshi, J.; Juste, A.; Kaadze, K.; Kajfasz, E.; Karmanov, D.; Kasper, P. A.; Katsanos, I.; Kehoe, R.; Kermiche, S.; Khalatyan, N.; Khanov, A.; Kharchilava, A.; Kharzheev, Y. N.; Khatidze, D.; Kirby, M. H.; Kohli, J. M.; Kozelov, A. V.; Kraus, J.; Kumar, A.; Kupco, A.; Kurča, T.; Kuzmin, V. A.; Kvita, J.; Lammers, S.; Landsberg, G.; Lebrun, P.; Lee, H. S.; Lee, S. W.; Lee, W. M.; Lellouch, J.; Li, L.; Li, Q. Z.; Lietti, S. M.; Lim, J. K.; Lincoln, D.; Linnemann, J.; Lipaev, V. V.; Lipton, R.; Liu, Y.; Liu, Z.; Lobodenko, A.; Lokajicek, M.; Love, P.; Lubatti, H. J.; Luna-Garcia, R.; Luty, M. A.; Lyon, A. L.; Maciel, A. K. A.; Mackin, D.; Madar, R.; Magaña-Villalba, R.; Malik, S.; Malyshev, V. L.; Maravin, Y.; Martínez-Ortega, J.; McCarthy, R.; McGivern, C. L.; Meijer, M. M.; Melnitchouk, A.; Menezes, D.; Mercadante, P. G.; Merkin, M.; Meyer, A.; Meyer, J.; Mondal, N. K.; Muanza, G. S.; Mulhearn, M.; Nagy, E.; Naimuddin, M.; Narain, M.; Nayyar, R.; Neal, H. A.; Negret, J. P.; Neustroev, P.; Nilsen, H.; Novaes, S. F.; Nunnemann, T.; Obrant, G.; Onoprienko, D.; Orduna, J.; Osman, N.; Osta, J.; Otero Y Garzón, G. J.; Owen, M.; Padilla, M.; Pangilinan, M.; Parashar, N.; Parihar, V.; Park, S. K.; Parsons, J.; Partridge, R.; Parua, N.; Patwa, A.; Penning, B.; Perfilov, M.; Peters, K.; Peters, Y.; Petrillo, G.; Pétroff, P.; Piegaia, R.; Piper, J.; Pleier, M.-A.; Podesta-Lerma, P. L. M.; Podstavkov, V. M.; Pol, M.-E.; Polozov, P.; Popov, A. V.; Prewitt, M.; Price, D.; Protopopescu, S.; Qian, J.; Quadt, A.; Quinn, B.; Rangel, M. S.; Ranjan, K.; Ratoff, P. N.; Razumov, I.; Renkel, P.; Rich, P.; Rijssenbeek, M.; Ripp-Baudot, I.; Rizatdinova, F.; Rominsky, M.; Royon, C.; Rubinov, P.; Ruchti, R.; Safronov, G.; Sajot, G.; Sánchez-Hernández, A.; Sanders, M. P.; Sanghi, B.; Santos, A. S.; Savage, G.; Sawyer, L.; Scanlon, T.; Schamberger, R. D.; Scheglov, Y.; Schellman, H.; Schliephake, T.; Schlobohm, S.; Schwanenberger, C.; Schwienhorst, R.; Sekaric, J.; Severini, H.; Shabalina, E.; Shary, V.; Shchukin, A. A.; Shivpuri, R. K.; Simak, V.; Sirotenko, V.; Skubic, P.; Slattery, P.; Smirnov, D.; Smith, K. J.; Snow, G. R.; Snow, J.; Snyder, S.; Söldner-Rembold, S.; Sonnenschein, L.; Sopczak, A.; Sosebee, M.; Soustruznik, K.; Spurlock, B.; Stark, J.; Stolin, V.; Stoyanova, D. A.; Strauss, E.; Strauss, M.; Strom, D.; Stutte, L.; Svoisky, P.; Takahashi, M.; Tanasijczuk, A.; Taylor, W.; Titov, M.; Tokmenin, V. V.; Tsybychev, D.; Tuchming, B.; Tully, C.; Tuts, P. M.; Uvarov, L.; Uvarov, S.; Uzunyan, S.; van Kooten, R.; van Leeuwen, W. M.; Varelas, N.; Varnes, E. W.; Vasilyev, I. A.; Verdier, P.; Vertogradov, L. S.; Verzocchi, M.; Vesterinen, M.; Vilanova, D.; Vint, P.; Vokac, P.; Wahl, H. D.; Wang, M. H. L. S.; Warchol, J.; Watts, G.; Wayne, M.; Weber, M.; Wetstein, M.; White, A.; Wicke, D.; Williams, M. R. J.; Wilson, G. W.; Wimpenny, S. J.; Wobisch, M.; Wood, D. R.; Wyatt, T. R.; Xie, Y.; Xu, C.; Yacoob, S.; Yamada, R.; Yang, W.-C.; Yasuda, T.; Yatsunenko, Y. A.; Ye, Z.; Yin, H.; Yip, K.; Yoo, H. D.; Youn, S. W.; Yu, J.; Zelitch, S.; Zhao, T.; Zhou, B.; Zhu, J.; Zielinski, M.; Zieminska, D.; Zivkovic, L.

    2010-11-01

    We report results of a search for particles with anomalously high ionization in events with a high transverse energy jet and large missing transverse energy in 2.4fb-1 of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron pp¯ collider. Production of such particles (quirks) is expected in scenarios with extra QCD-like SU(N) sectors, and this study is the first dedicated search for such signatures. We find no evidence of a signal and set a lower mass limit of 107, 119, and 133 GeV for the mass of a charged quirk with strong dynamics scale Λ in the range from 10 keV to 1 MeV and N=2, 3, and 5, respectively.

  16. 120 MW, 800 MHz Magnicon for a Future Muon Collider

    SciTech Connect

    Jay L. Hirshfield

    2005-12-15

    Development of a pulsed magnicon at 800 MHz was carried out for the muon collider application, based on experience with similar amplifiers in the frequency range between 915 MHz and 34.3 GHz. Numerical simulations using proven computer codes were employed for the conceptual design, while established design technologies were incorporated into the engineering design. A cohesive design for the 800 MHz magnicon amplifier was carried out, including design of a 200 MW diode electron gun, design of the magnet system, optimization of beam dynamics including space charge effects in the transient and steady-state regimes, design of the drive, gain, and output cavities including an rf choke in the beam exit aperture, analysis of parasitic oscillations and design means to eliminate them, and design of the beam collector capable of 20 kW average power operation.

  17. Search for quirks at the Fermilab Tevatron Collider

    SciTech Connect

    Abazov, V.M.; Abbott, B.; Abolins, M.; Acharya, B.S.; Adams, M.; Adams, T.; Alexeev, G.D.; Alkhazov, G.; Alton, A.; Alverson, G.; Alves, G.A.; /Rio de Janeiro, CBPF /NIKHEF, Amsterdam

    2010-08-01

    We report results of a search for particles with anomalously high ionization in events with a high transverse energy jet and large missing transverse energy in 2.4 fb{sup -1} of integrated luminosity collected by the D0 experiment at the Fermilab Tevatron p{bar p} collider. Production of such particles (quirks) is expected in scenarios with extra QCD-like SU(N) sectors, and this study is the first dedicated search for such signatures. We find no evidence of a signal and set a lower mass limit of 107 GeV for the mass of a charged quirk with strong dynamics scale {Lambda} in the range from 10 keV to 1 MeV.

  18. Extrapolation technique pitfalls in asymmetry measurements at colliders

    NASA Astrophysics Data System (ADS)

    Colletti, Katrina; Hong, Ziqing; Toback, David; Wilson, Jonathan S.

    2016-09-01

    Asymmetry measurements are common in collider experiments and can sensitively probe particle properties. Typically, data can only be measured in a finite region covered by the detector, so an extrapolation from the visible asymmetry to the inclusive asymmetry is necessary. Often a constant multiplicative factor is advantageous for the extrapolation and this factor can be readily determined using simulation methods. However, there is a potential, avoidable pitfall involved in the determination of this factor when the asymmetry in the simulated data sample is small. We find that to obtain a reliable estimate of the extrapolation factor, the number of simulated events required rises as the inverse square of the simulated asymmetry; this can mean that an unexpectedly large sample size is required when determining the extrapolation factor.

  19. Collider signatures of Higgs-portal scalar dark matter

    NASA Astrophysics Data System (ADS)

    Han, Huayong; Yang, Jin Min; Zhang, Yang; Zheng, Sibo

    2016-05-01

    In the simplest Higgs-portal scalar dark matter model, the dark matter mass has been restricted to be either near the resonant mass (mh / 2) or in a large-mass region by the direct detection at LHC Run 1 and LUX. While the large-mass region below roughly 3 TeV can be probed by the future Xenon1T experiment, most of the resonant mass region is beyond the scope of Xenon1T. In this paper, we study the direct detection of such scalar dark matter in the narrow resonant mass region at the 14 TeV LHC and the future 100 TeV hadron collider. We show the luminosities required for the 2σ exclusion and 5σ discovery.

  20. Self-sustaining charging of identical colliding particles.

    PubMed

    Siu, Theo; Cotton, Jake; Mattson, Gregory; Shinbrot, Troy

    2014-05-01

    Recent experiments have demonstrated that identical material samples can charge one another after being brought into symmetric contact. The mechanism for this charging is not known. In this article, we use a simplified one-dimensional lattice model to analyze charging in the context of agitated particles. We find that the electric field from a single weakly polarized grain can feed back on itself by polarizing its neighbors, leading to an exponential growth in polarization. We show that, by incorporating partial neutralization between neighboring polarized particles, either uniform alignment of dipoles or complex charge and polarization waves can be produced. We reproduce a polarized state experimentally using identical colliding particles and raise several issues for future study. PMID:25353788

  1. An Energy Recovery Electron Linac On Ring Collider

    SciTech Connect

    Nikolitsa Merminga; Geoffrey Krafft; Valeri Lebedev; Ilan Ben-Zvi

    2001-09-01

    Electron-proton/ion colliders with center of mass energies between 14 GeV and 100 GeV (protons) or 63 GeV/A (ions) and luminosities at the 10{sup 33} (per nucleon) level have been proposed recently as a means for studying hadronic structure. Electron beam polarization appears to be crucial for many of the experiments. Two accelerator design scenarios have been examined in detail: colliding rings and recirculating linac-on-ring. Although the linac-on-ring scenario is not as well developed as the ring-ring scenario, comparable luminosities appear feasible. The linac-on-ring option presents significant advantages with respect to: (1) spin manipulations; (2) reduction of the synchrotron radiation load in the detectors; (3) a wide range of continuous energy variability. Rf power and beam dump considerations require that the electron linac recover the beam energy. This technology has been demonstrated at Jefferson Lab's IR FEL with cw current up to 5 mA and beam energy up to 50 MeV. Based on extrapolations from actual measurements and calculations, energy recovery is expected to be feasible at higher currents (a few hundred mA) and higher energies (a few GeV) as well. The report begins with a brief overview of Jefferson Lab's experience with energy recovery and summarize its benefits. Luminosity projections for the linac-ring scenario based on fundamental limitations are presented next. The feasibility of an energy recovery electron linac-on-proton ring collider is investigated and four conceptual point designs are shown corresponding to electron to proton energies of: 3 GeV on 15 GeV, 5 GeV on 50 GeV and 10 GeV on 250 GeV, and for gold ions with 100 GeV/A. The last two designs assume that the protons or ions are stored in the existing RHIC accelerator. Accelerator physics issues relevant to proton rings and energy recovery linacs are discussed next and a list of required R and D for the realization of such a design is presented.

  2. Test of Relativistic Gravity for Propulsion at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Felber, Franklin

    2010-01-01

    A design is presented of a laboratory experiment that could test the suitability of relativistic gravity for propulsion of spacecraft to relativistic speeds. An exact time-dependent solution of Einstein's gravitational field equation confirms that even the weak field of a mass moving at relativistic speeds could serve as a driver to accelerate a much lighter payload from rest to a good fraction of the speed of light. The time-dependent field of ultrarelativistic particles in a collider ring is calculated. An experiment is proposed as the first test of the predictions of general relativity in the ultrarelativistic limit by measuring the repulsive gravitational field of bunches of protons in the Large Hadron Collider (LHC). The estimated `antigravity beam' signal strength at a resonant detector of each proton bunch is 3 nm/s2 for 2 ns during each revolution of the LHC. This experiment can be performed off-line, without interfering with the normal operations of the LHC.

  3. Solid State Technology Meets Collider Challenge

    SciTech Connect

    Hazi, A

    2005-09-20

    Probing the frontiers of particle physics and delving into the mysteries of the universe and its beginnings require machines that can accelerate beams of fundamental particles to very high energies and then collide those beams together, producing a multitude of exotic subatomic particles. The proposed Next Linear Collider (NLC), being developed by Stanford Linear Accelerator Center (SLAC), Lawrence Livermore and Lawrence Berkeley national laboratories, and Fermi National Accelerator Laboratory (Fermilab), is such a machine. The NLC is expected to produce a variety of subatomic particles by smashing together electrons and their antimatter counterparts (positrons) at nearly the speed of light with energies in the teraelectronvolt (TeV) range. Plans are that the NLC will initially operate at 0.5 TeV and ultimately be scaled up to 1.5 TeV. (See S&TR, April 2000, pp. 12-16.) Work at the facility will complement the research to be conducted at another high-energy particle accelerator, the 14-TeV Large Hadron Collider at the European Laboratory for Particle Physics (commonly known by the acronym CERN from its former name) in Geneva, which is scheduled for completion in 2007. Achieving beam energy levels in the TeV range requires modulator systems that can convert ac line power--the same type of power one gets from the wall plug--into dc pulses. Ultimately, these pulses are transformed into radiofrequency (rf) pulses that ''kick'' the particles up to the required energy levels. Livermore scientists and engineers have designed a solid-state modulator to replace oldstyle modulators based on vacuum-tube technology. These new modulators promise to be far more efficient, reliable, and serviceable than the previous components. Livermore's Laboratory Directed Research and Development Program supported the basic research and development on the solid-state modulator technology, and SLAC supported the systems integration.

  4. Chromaticity correction for a muon collider optics

    SciTech Connect

    Alexahin, Y.; Gianfelice-Wendt, E.; Kapin, V.; /Fermilab

    2011-03-01

    Muon Collider (MC) is a promising candidate for the next energy frontier machine. However, in order to obtain peak luminosity in the 10{sup 34} cm{sup 2}s{sup -1} range the collider lattice designmust satisfy a number of stringent requirements. In particular the expected large momentum spread of the muon beam and the very small {beta}* call for a careful correction of the chromatic effects. Here we present a particular solution for the interaction region (IR) optics whose distinctive feature is a three-sextupole local chromatic correction scheme. The scheme may be applied to other future machines where chromatic effects are expected to be large. The expected large muon energy spread requires the optics to be stable over a wide range of momenta whereas the required luminosity calls for {beta}* in the mm range. To avoid luminosity degradation due to hour-glass effect, the bunch length must be comparatively small. To keep the needed RF voltage within feasible limits the momentum compaction factor must be small over the wide range of momenta. A low {beta}* means high sensitivity to alignment and field errors of the Interaction Region (IR) quadrupoles and large chromatic effects which limit the momentum range of optics stability and require strong correction sextupoles, which eventually limit the Dynamic Aperture (DA). Finally, the ring circumference should be as small as possible, luminosity being inversely proportional to the collider length. A promising solution for a 1.5 TeV center of mass energy MC with {beta}* = 1 m in both planes has been proposed. This {beta}* value has been chosen as a compromise between luminosity and feasibility based on the magnet design and energy deposition considerations. The proposed solution for the IR optics together with a new flexible momentum compaction arc cell design allows to satisfy all requirements and is relatively insensitive to the beam-beam effect.

  5. Electron Cloud Effect in the Linear Colliders

    SciTech Connect

    Pivi, M

    2004-09-13

    Beam induced multipacting, driven by the electric field of successive positively charged bunches, may arise from a resonant motion of electrons, generated by secondary emission, bouncing back and forth between opposite walls of the vacuum chamber. The electron-cloud effect (ECE) has been observed or is expected at many storage rings [1]. In the beam pipe of the Damping Ring (DR) of a linear collider, an electron cloud is produced initially by ionization of the residual gas and photoelectrons from the synchrotron radiation. The cloud is then sustained by secondary electron emission. This electron cloud can reach equilibrium after the passage of only a few bunches. The electron-cloud effect may be responsible for collective effects as fast coupled-bunch and single-bunch instability, emittance blow-up or incoherent tune shift when the bunch current exceeds a certain threshold, accompanied by a large number of electrons in the vacuum chamber. The ECE was identified as one of the most important R&D topics in the International Linear Collider Report [2]. Systematic studies on the possible electron-cloud effect have been initiated at SLAC for the GLC/NLC and TESLA linear colliders, with particular attention to the effect in the positron main damping ring (MDR) and the positron Low Emittance Transport which includes the bunch compressor system (BCS), the main linac, and the beam delivery system (BDS). We present recent computer simulation results for the main features of the electron cloud generation in both machine designs. Thus, single and coupled-bunch instability thresholds are estimated for the GLC/NLC design.

  6. Accelerator R&D toward Muon Collider and Neutrino Factory

    SciTech Connect

    Shiltsev, Vladimir; /Fermilab

    2009-10-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture, accelerate and collide high intensity beams of muons. At present, a high-luminosity multi-TeV muon collider presents a viable option for the next generation lepton-lepton collider, which is believed to be needed to fully explore high energy physics in the era following LHC discoveries. Such a collider can offer superb energy resolution, smaller size, and potentially cost and power consumption compared to multi-TeV e{sup +}e{sup -} linear colliders. This article briefly reviews the motivation, design and status of accelerator R&D for Muon Collider and Neutrino Factory.

  7. Accelerator R&D toward Muon Collider and Neutrino Factory

    NASA Astrophysics Data System (ADS)

    Shiltsev, V.

    2010-12-01

    Over the last decade there has been significant progress in developing the concepts and technologies needed to produce, capture, accelerate and collide high intensity beams of muons. At present, a high-luminosity multi-TeV muon collider presents a viable option for the next generation lepton-lepton collider, which is believed to be needed to fully explore high energy physics in the era following LHC discoveries. Such a collider can offer superb energy resolution, smaller size, and potentially cost and power consumption compared to multi-TeV e + e - linear colliders. This article briefly reviews the motivation, design and status of accelerator R&D for Muon Collider and Neutrino Factory.

  8. 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.

  9. Current Correlations from a Mesoscopic Anyon Collider.

    PubMed

    Rosenow, Bernd; Levkivskyi, Ivan P; Halperin, Bertrand I

    2016-04-15

    Fermions and bosons are fundamental realizations of exchange statistics, which governs the probability for two particles being close to each other spatially. Anyons in the fractional quantum Hall effect are an example for exchange statistics intermediate between bosons and fermions. We analyze a mesoscopic setup in which two dilute beams of anyons collide with each other, and relate the correlations of current fluctuations to the probability of particles excluding each other spatially. While current correlations for fermions vanish, negative correlations for anyons are a clear signature of a reduced spatial exclusion as compared to fermions. PMID:27127979

  10. Magnetic merging in colliding flux tubes

    NASA Technical Reports Server (NTRS)

    Zweibel, Ellen G.; Rhoads, James E.

    1995-01-01

    We develop an analytical theory of reconnection between colliding, twisted magnetic flux tubes. Our analysis is restricted to direct collisions between parallel tubes and is based on the collision dynamics worked out by Bogdan (1984). We show that there is a range of collision velocities for which neutral point reconnection of the Parker-Sweet type can occur, and a smaller range for which reconnection leads to coalescence. Mean velocities within the solar convection zone are probably significantly greater than the upper limit for coalescence. This suggests that the majority of flux tube collisions do not result in merging, unless the frictional coupling of the tubes to the background flow is extremely strong.

  11. Next linear collider test accelerator injector upgrade

    SciTech Connect

    Yeremian, A.D.; Miller, R.H.

    1995-12-31

    The Next Linear Collider Test Accelerator (NLCTA) is being constructed at SLAC to demonstrate multibunch beam loading compensation, suppression of higher order deflecting modes and measure transverse components of the accelerating fields in X-band accelerating structures. Currently a simple injector which provides the average current necessary for the beam loading compensations studies is under construction. An injector upgrade is planned to produce bunch trains similar to that of the NLC with microbunch intensity, separation and energy spread, identical to that of NLC. We discuss the design of the NLCTA injector upgrade.

  12. The next linear collider damping ring lattices

    SciTech Connect

    Wolski, Andrzej; Corlett, John N.

    2001-06-20

    We report on the lattice design of the Next Linear Collider (NLC) damping rings. The damping rings are required to provide low emittance electron and positron bunch trains to the NLC linacs, at a rate of 120 Hz. We present an optical design, based on a theoretical minimum emittance (TME) lattice, to produce the required normalized extracted beam emittances gex = 3 mm-mrad and gey = 0.02 mm mrad. An assessment of dynamic aperture and non-linear effects is given. The positron pre-damping ring, required to reduce the emittance of the positron beam such that it may be accepted by a main damping ring, is also described.

  13. Simulations of high disruption colliding beams

    SciTech Connect

    Boyce, J.R.; Heifets, S.; Krafft, G.A.

    1990-09-01

    Recent B-factory proposals that use a linac beam colliding with the beam from a storage ring to achieve high luminosities (L > 10{sup 34} cm{sup {minus}2}sec{sup {minus}1}) result in very high disruption of the linac beam. The effects of such high disruption have been studied using the relativistic, 3-D code SWARM. We discuss the assumptions, parameters, and results of a series of runs that model such collisions. Regimes of high beam loss and methods to avoid them are also discussed. 5 refs., 4 figs.

  14. Stochastic cooling requirements for a muon collider

    SciTech Connect

    Ruggiero, A.G.

    1993-12-31

    The most severe limitation to the muon production for a large-energy muon collider is the short time allowed for cooling the beam to dimensions small enough to provide reasonably high luminosity. The limitation is caused by the short lifetime of the particles. It appears to be desirable to accelerate the beam quickly in very short bunches. This paper describes the requirements of single-pass, fast stochastic cooling for very short bunches. Bandwidth, amplifier gain and Schottky power do not seem to be of major concern. Problems do arise with the ultimate low emittance that can be achieved, the value of which is seriously affected by the front-end noise.

  15. Broader Impacts of the International Linear Collider

    SciTech Connect

    Bardeen, M.; Ruchti, R.

    2005-08-01

    Large-scale scientific endeavors such as the International Linear Collider Project can have a lasting impact on education and outreach to our society. The ILC will provide a discovery platform for frontier physical science and it will also provide a discovery platform for broader impacts and social science. The importance of Broader Impacts of Science in general and the ILC in particular are described. Additionally, a synopsis of education and outreach activities carried out as an integral part of the Snowmass ILC Workshop is provided.

  16. Black holes at the Large Hadron Collider.

    PubMed

    Dimopoulos, S; Landsberg, G

    2001-10-15

    If the scale of quantum gravity is near TeV, the CERN Large Hadron Collider will be producing one black hole (BH) about every second. The decays of the BHs into the final states with prompt, hard photons, electrons, or muons provide a clean signature with low background. The correlation between the BH mass and its temperature, deduced from the energy spectrum of the decay products, can test Hawking's evaporation law and determine the number of large new dimensions and the scale of quantum gravity. PMID:11690198

  17. Precision Event Simulation for Hadron Colliders

    NASA Astrophysics Data System (ADS)

    Hoeche, Stefan

    2016-03-01

    Hadron colliders are workhorses of particle physics, enabling scientific breakthroughs such as the discovery of the Higgs boson. Hadron beams reach the highest energies, but they also produce very complex collisions. Studying the underlying dynamics requires involved multi-particle calculations. Over the past decades Monte-Carlo simulation programs were developed to tackle this task. They have by now evolved into precision tools for theorists and experimenters alike. This talk will give an introduction to event generators and discuss the current status of development.

  18. Drell-Yan production at collider energies

    SciTech Connect

    Neerven, W.L. Van

    1995-07-01

    We present some results of the Drell-Yan cross sections d{sigma}/dm and {sigma}{sub tot} which includes the O ({alpha}{sub s}{sup 2}) contribution to the coefficient function. In particular we study the total cross section {sigma}{sub tot} for vector boson production and d{sigma}/dm for low invariant masses m of the lepton pairs at large hadron collider energies. This study includes a detailed discussion of the dependence of the cross sections on the chosen scheme ({bar M}S versus DIS) and the factorization scale.

  19. Quantum production of black holes at colliders

    NASA Astrophysics Data System (ADS)

    Arsene, Nicusor; Casadio, Roberto; Micu, Octavian

    2016-07-01

    We investigate black hole production in p p collisions at the Large Hadron Collider by employing the horizon quantum mechanics for models of gravity with extra spatial dimensions. This approach can be applied to processes around the fundamental gravitational scale and naturally yields a suppression below the fundamental gravitational scale and for increasing number of extra dimensions. The results of numerical simulations performed with the black hole event generator BLACKMAX are here reported in order to illustrate the main differences in the numbers of expected black hole events and mass distributions.

  20. Rf power sources for linear colliders

    SciTech Connect

    Allen, M.A.; Callin, R.S.; Caryotakis, G.; Deruyter, H.; Eppley, K.R.; Fant, K.S.; Farkas, Z.D.; Fowkes, W.R.; Hoag, H.A.; Feinstein, J.; Ko, K.; Koontz, R.F.; Kroll, N.M.; Lavine, T.L.; Lee, T.G.; Loew, G.A.; Miller, R.H.; Nelson, E.M.; Ruth, R.D.; Vlieks, A.E.; Wang, J.W.; Wilson, P.B. ); Boyd, J.K.; Houk, T.; Ryne, R.D.; Westenskow, G.A.; Yu, S.S. (Lawrence Live

    1990-06-01

    The next generation of linear colliders requires peak power sources of over 200 MW per meter at frequencies above 10 GHz at pulse widths of less than 100 nsec. Several power sources are under active development, including a conventional klystron with rf pulse compression, a relativistic klystron (RK) and a crossed-field amplifier. Power from one of these has energized a 0.5 meter two- section High Gradient Accelerator (HGA) and accelerated a beam at over 80 MeV meter. Results of tests with these experimental devices are presented here.

  1. A COMPLETE SCHEME FOR A MUON COLLIDER.

    SciTech Connect

    PALMER,R.B.; BERG, J.S.; FERNOW, R.C.; GALLARDO, J.C.; KIRK, H.G.; ALEXAHIN, Y.; NEUFFER, D.; KAHN, S.A.; SUMMERS, D.

    2007-09-01

    A complete scheme for production, cooling, acceleration, and ring for a 1.5 TeV center of mass muon collider is presented, together with parameters for two higher energy machines. The schemes starts with the front end of a proposed neutrino factory that yields bunch trains of both muon signs. Six dimensional cooling in long-period helical lattices reduces the longitudinal emittance until it becomes possible to merge the trains into single bunches, one of each sign. Further cooling in all dimensions is applied to the single bunches in further helical lattices. Final transverse cooling to the required parameters is achieved in 50 T solenoids.

  2. Two gauge boson physics at future colliders

    SciTech Connect

    Cahn, R.N.

    1988-05-13

    Electroweak unification suggests that there should be WW and ZZ physics analogous to {gamma}{gamma} physics. Indeed, WW and ZZ collisions will provide an opportunity to search for the Higgs boson at future high energy colliders. Cross sections in the picobarn range are predicted for Higgs boson production at the proposed 40-TeV SSC. While other states may be produced by WW and ZZ collisions, it is the Higgs boson that looms as the most attractive objective. 31 refs., 5 figs.

  3. String resonances at the Large Hadron Collider

    SciTech Connect

    Roy, Arunava; Cavaglia, Marco

    2009-07-01

    The Large Hadron Collider promises to discover new physics beyond the standard model. An exciting possibility is the formation of string resonances at the TeV scale. In this article, we show how string resonances may be detected at the LHC in the pp{yields}{gamma}+jet channel. Our study is based on event-shape variables, missing energy and momentum, maximum transverse momentum of photons and dijet invariant mass. These observables provide interesting signatures which enable us to discriminate string events from the standard model background.

  4. High energy accelerator and colliding beam user group. Progress report, March 1, 1983-February 29, 1984

    SciTech Connect

    Not Available

    1983-01-01

    Topics covered in this research summary include: status of the OPAL collaboration at LEP, CERN; two-photon physics at PLUTO; search for new particles at JADE; neutrinoless double beta decay at DESY; Fermilab jet experiment; neutrino deuterium experiment in the 15 foot bubble chamber at Fermilab; deep inelastic muon experiment at Fermilab; new experiments at the proton-antiproton collider; neutrino-electron scattering at Los Alamos; parity violation in proton-proton scattering; an upgrade of laboratory and computer facilities; and a study of bismuth germanate as a durable scintillation crystal. (GHT)

  5. From the SLAC linear collider to the next linear collider: A status report and road map

    SciTech Connect

    Richter, B.

    1992-02-01

    In this presentation, I will review what we have learned about linear colliders, the problems that have been uncovered, and the technology-development program aimed at realizing the next high energy machine. I will then close with a few comments on how to get on with the job of building it.

  6. Higgs boson production with heavy quarks at hadron colliders

    NASA Astrophysics Data System (ADS)

    Jackson, Christopher B.

    2005-11-01

    One of the remaining puzzles in particle physics is the origin of electroweak symmetry breaking. In the Standard Model (SM), a single doublet of complex scalar fields is responsible for breaking the SU(2) L x U(1)Y gauge symmetry thus giving mass to the electroweak gauge bosons via the Higgs mechanism and to the fermions via Yukawa couplings. The remnant of the process is a vet to he discovered scalar particle, the Higgs boson (h). However, current and future experiments at hadron colliders hold great promise. Of particular interest at hadron colliders is the production of a Higgs boson in association with a pair of heavy quarks, pp¯(pp) → QQ¯h, where Q can be either a top or a bottom quark. Indeed, the production of a Higgs boson with a pair of top quarks provides a very distinctive signal in hadronic collisions where background processes are formidable, and it will be instrumental in the discovery of a Higgs boson below about 130 GeV at the LHC. On the other hand, the production of a Higgs boson with bottom quarks can be strongly enhanced in models of new physics beyond the SM, e.g. supersymmetric models. If this is the case, bb¯h production will play a crucial role at the Tevatron where it could provide the first signal of new physics. Given the prominent role that Higgs production with heavy quarks can play at hadron colliders, it becomes imperative to have precise theoretical predictions for total and differential cross sections. In this dissertation, we outline and present detailed results for the next-to-leading order (NLO) calculation of the Quantum Chromodynamic (QCD) corrections to QQ¯h production at both the Tevatron and the LHC. This calculation involves several difficult issues due to the three massive particles in the final state, a situation which is at the frontier of radiative correction calculations in quantum field theory. We detail the novel techniques developed to deal with these challenges. The calculation of pp¯(pp) → bb¯h at NLO in

  7. Numerical calculation of ion polarization in the NICA collider

    NASA Astrophysics Data System (ADS)

    Kovalenko, A. D.; Butenko, A. V.; Kekelidze, V. D.; Mikhaylov, V. A.; Kondratenko, M. A.; Kondratenko, A. M.; Filatov, Yu N.

    2016-02-01

    The NICA Collider with two solenoid Siberian snakes is “transparent” to the spin. The collider transparent to the spin provides a unique capability to control any polarization direction of protons and deuterons using additional weak solenoids without affecting orbital parameters of the beam. The spin tune induced by the control solenoids must significantly exceed the strength of the zero-integer spin resonance, which contains a coherent part associated with errors in the collider's magnetic structure and an incoherent part associated with the beam emittances. We present calculations of the coherent part of the resonance strength in the NICA collider for proton and deuteron beams.

  8. Far Future Colliders and Required R&D Program

    SciTech Connect

    Shiltsev, V.; /Fermilab

    2012-06-01

    Particle colliders for high energy physics have been in the forefront of scientific discoveries for more than half a century. The accelerator technology of the collider has progressed immensely, while the beam energy, luminosity, facility size and the cost have grown by several orders of magnitude. The method of colliding beams has not fully exhausted its potential but its pace of progress has greatly slowed down. In this paper we very briefly review the R&D toward near future colliders and make an attempt to look beyond the current horizon and outline the changes in the paradigm required for the next breakthroughs.

  9. Tau anomalous magnetic moment in γγ colliders

    NASA Astrophysics Data System (ADS)

    Peressutti, Javier; Sampayo, Oscar A.

    2012-08-01

    We investigate the possibility of setting model independent limits for a nonstandard anomalous magnetic moment aτNP of the tau lepton, in future γγ colliders based on Compton backscattering. For a hypothetical collider we find that, at various levels of confidence, the limits for aτNP could be improved, compared to previous studies based on LEP1, LEP2 and SLD data. We show the results for a realistic range of the center of mass energy of the e+e- collider. As a more direct application, we also present the results of the simulation for the photon collider at the TESLA project.

  10. Fast cooling, muon acceleration and the prospect of muon colliders

    NASA Astrophysics Data System (ADS)

    Palmer, Mark

    Facilities based on stored muons offer unique potential for future high-energy physics capabilities. Three key characteristics of the muon make this possible: * The muon is a lepton; * The muon is roughly 200 times as massive as the electron; * The muon decays to an electron and two neutrinos. As the next heavier members of the lepton family with respect to the electron and positron, μ+ and μ-. beams can be collided to provide a precision lepton probe of the electroweak couplings. This makes a muon collider a suitable option for a lepton collider companion to a hadron collider discovery machine...

  11. The Very Large Hadron Collider: The farthest energy frontier

    SciTech Connect

    Barletta, William A.

    2001-06-21

    The Very Large Hadron Collider (or Eloisatron) represents what may well be the final step on the energy frontier of accelerator-based high energy physics. While an extremely high luminosity proton collider at 100-200 TeV center of mass energy can probably be built in one step with LHC technology, that machine would cost more than what is presently politically acceptable. This talk summarizes the strategies of collider design including staged deployment, comparison with electron-positron colliders, opportunities for major innovation, and the technical challenges of reducing costs to manageable proportions. It also presents the priorities for relevant R and D for the next few years.

  12. Klystron switching power supplies for the Internation Linear Collider

    SciTech Connect

    Fraioli, Andrea; /Cassino U. /INFN, Pisa

    2009-12-01

    The International Linear Collider is a majestic High Energy Physics particle accelerator that will give physicists a new cosmic doorway to explore energy regimes beyond the reach of today's accelerators. ILC will complement the Large Hadron Collider (LHC), a proton-proton collider at the European Center for Nuclear Research (CERN) in Geneva, Switzerland, by producing electron-positron collisions at center of mass energy of about 500 GeV. In particular, the subject of this dissertation is the R&D for a solid state Marx Modulator and relative switching power supply for the International Linear Collider Main LINAC Radio Frequency stations.

  13. ICOOL: A TOOL FOR MUON COLLIDER SIMULATIONS.

    SciTech Connect

    FERNOW,R.C.

    2001-09-28

    Current ideas for designing neutrino factories [ 1,2] and muon colliders [3] require unique configurations of fields and materials to prepare the muon beam for acceleration. This so-called front end system must accomplish the goals of phase rotation, bunching and cooling. We have continued the development of a 3-D tracking code, ICOOL [4], for examining possible muon collider front end configurations. A system is described in terms of a series of longitudinal regions with associated material and field properties. The tracking takes place in a coordinate system that follows a reference orbit through the system. The code takes into account decays and interactions of {approx}50-500 MeV/c muons in matter. Material geometry regions include cylinders and wedges. A number of analytic models are provided for describing the field configurations. Simple diagnostics are built into the code, including calculation of emittances and correlations, longitudinal traces, histograms and scatter plots. A number of auxiliary codes can be used for pre-processing, post-processing and optimization.

  14. The Large Hadron Collider, a personal recollection

    NASA Astrophysics Data System (ADS)

    Evans, Lyndon

    2014-03-01

    The construction of the Large Hadron Collider (LHC) has been a massive endeavor spanning almost 30 years from conception to commissioning. Building the machine with the highest possible energy (7 TeV) in the existing LEP tunnel of 27 km circumference and with a tunnel diameter of only 3.8 m has required considerable innovation. The first was the development of an idea first proposed by Bob Palmer at Brookhaven National Laboratory in 1978, where the two rings are integrated into a single magnetic structure. This compact 2-in-1 structure was essential for the LHC due to both the limited space available in the existing Large Electron-Positron collider tunnel and the cost. The second innovation was the bold move to use superfluid helium cooling on a massive scale, which was imposed by the need to achieve a high (8.3 T) magnetic field using an affordable Nb-Ti superconductor. In this article, no attempt is made to give a comprehensive review of the machine design. This can be found in the LHC Design Report [1], which gives a detailed description of the machine as it was built and comprehensive references. A more popular description of the LHC and its detectors can be found in [2]. Instead, this is a more personal account of the project from approval to commissioning, describing some of the main technologies and some of the trials and tribulations encountered in bringing this truly remarkable machine alive.

  15. The muon collider (Sandro`s snake)

    SciTech Connect

    Ruggiero, A.G.

    1992-12-31

    This paper describes a feasibility study for the design of a muon collider. Recognized the fact that the particle lifetime increases linearly with the energy, we have adopted a scheme where steps of cooling and acceleration are entwined. We have indeed found convenient to accelerate the beam as fast as possible to increase its chances of survival, and necessary to dilute the action of cooling throughout the entire accelerating process to make it more effective and affordable. All acceleration and cooling steps are executed in a single pass essentially along a curvilinear and open path. We do not believe it is possible to handle the beam otherwise in circular and closed rings, as it has been proposed in the past. The example shown in this paper describes a muon collider at the energy of 250 GeV per beam and a luminosity of 4 {times} 10{sup 28} cm{sup {minus}2}s{sup {minus}1}. We have adopted an extrapolation of the stochastic cooling method for the reduction of the beam emittance.

  16. 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.

  17. Mass reach scaling for future hadron colliders

    NASA Astrophysics Data System (ADS)

    Rizzo, Thomas G.

    2015-04-01

    The primary goal of any future hadron collider is to discover new physics (NP) associated with a high mass scale, , beyond the range of the LHC. In order to maintain the same relative mass reach for rate-limited NP, , as increases, Richter recently reminded us that the required integrated luminosity obtainable at future hadron colliders (FHC) must grow rapidly, , in the limit of naive scaling. This would imply, e.g., a 50-fold increase in the required integrated luminosity when going from the 14 TeV LHC to a FHC with TeV, an increase that would prove quite challenging on many different fronts. In this paper we point out, due to the scaling violations associated with the evolution of the parton density functions (PDFs) and the running of the strong coupling, , that the actual luminosity necessary in order to maintain any fixed value of the relative mass reach is somewhat greater than this scaling result indicates. However, the actual values of the required luminosity scaling are found to be dependent upon the detailed nature of the NP being considered. Here we elucidate this point explicitly by employing several specific benchmark examples of possible NP scenarios and briefly discuss the (relatively weak) search impact in each case if these luminosity goals are not met.

  18. Letter of Intent for a Tevatron Collider Beauty Factory

    SciTech Connect

    Volk, J.T.; Yager, P.M.; Edelstein, R.; Christian, D.; Lundberg, B.; Reay, N.W.; Reibel, K.; Sidwell, R.A.; Stanton, N.; Kalbfleisch, G.R.; Skubic, P.; /Oklahoma U.

    1987-01-01

    A hadron collider beauty production experiment which will increase our knowledge of mixing, rare decay modes and even of CP violation could be performed using a new type of detector at the upgraded Fermilab Tevatron. In order to progress from the hundreds of thousands of B{bar B} events which can be tagged per year at a luminosity of several times 10{sup 29}/cm{sup 2}-sec to an ultimate yield of tens of millions at a luminosity of several times 10{sup 31}/cm{sup 2}-sec, they also must embark on a learning curve which will take many years and will require development both of hardware and software before achieving a final system. A new high-luminosity intersection region would have to be included as part of the presently-planned Tevatron Collider upgrade. Designing and constructing an initial system will take four years. Thus, in the light of the positive decision on the SSC, a start must be made soon if Fermilab is ever to play a strong role in this exciting area of physics. Designing even the initial system will require several man-years of effort by a dedicated group of people, together with concurrent work in prototyping and testing. They therefore ask that the Physics Advisory Committee give us their opinion of the priority such a project should be given at Fermilab, within the context that eventually it will require a devoted interaction region which accesses the full achieved luminosity of the machine. Initially, they discuss physics accessible as the B{bar B} yield increases. Subsequently, they outline a detector which can be staged, increasing its power (and cost) as we progress along our learning curve. Finally, costs and time schedules are estimated for the initial version of this detector and possible locations are discussed.

  19. Strong Electroweak Symmetry Breaking in the Large Hadron Collider Era

    NASA Astrophysics Data System (ADS)

    Evans, Jared Andrew

    2011-12-01

    With the Large Hadron Collider collecting data, both the pursuit of novel detection techniques and the exploration of new ideas are more important than ever. Novel detection techniques are essential in order for the community to garner the most worth from the machine. New ideas are needed both to expand the boundaries of what could be observed and to foster the creative mindset of the community that moves particle physics into fascinating, and often unexpected, directions. Discovering whether electroweak symmetry is broken strongly or weakly is one of the most pressing questions to be answered. Exploring the possibility of strong electroweak symmetry breaking is the topic of this work. The first of two major sectors in this work concerns the theory of conformal technicolor. We present the low energy minimal model for conformal technicolor and verify that it can satisfy current constraints from experiment. We will also provide a UV completion for this model, which realistically extends the sector with high-energy supersymmetry. Two complete models of flavor are presented. This is the first example of a complete, consistent model of strong electroweak symmetry breaking. The second of the two sectors discusses experimental signatures arising in a large class of general technicolor models at the Large Hadron Collider. The possible existence of narrow scalar states that can be produced via gluon-gluon fusion is first discussed. These states can decay into exotic final states of multiple electroweak gauge bosons, third generation particles and even light composite Higgs particles. A two Higgs doublet model is proposed as an effective way to model these exciting states. Lastly, we discuss the array of possible final states and their possible discovery.

  20. B factory at RHIC (Relativistic Heavy Ion Collider)

    SciTech Connect

    Lockyer, N.S.; Van Berg, R.; Newcomer, F.M.; Foley, K.; Morse, W.; Paige, F.; Polychronakos, V.; Protopopescu, S.; Rehak, P.; Sidwell, R.

    1988-01-01

    A dedicated B physics experiment located in the proposed Relativistic Heavy Ion Collider at Brookhaven (RHIC) is considered. The machine may operate in a p-p mode with a luminosity in excess of 10/sup 32/ cm/sup /minus/2/ sec/sup /minus/1/ at 250 /times/ 250 GeV. The estimated B/bar B/ cross section at these energies is about 10 ..mu..barns and a run of 10/sup 7/ sec would produce roughly 10/sup 10/ B/bar B/ pairs. A comparison to similar ideas proposed for the Fermilab Tevatron Upgrade and the SSC are discussed. The most ambitious physics objective of such an experiment would be the study of CP nonconservation. Particular emphasis at this workshop was given to the self tagging mode B ..-->.. K/sup +/..pi../sup /minus//. Experimental techniques developed during this experiment would be extremely useful for more ambitious projects anticipated at the SSC. 36 refs., 10 figs.

  1. Turbulent amplification of magnetic fields in colliding laboratory jets

    NASA Astrophysics Data System (ADS)

    Tzeferacos, P.; Meinecke, J.; Bell, A. R.; Doyle, H.; Bingham, R.; Churazov, E. M.; Crowston, R.; Murphy, C. D.; Woolsey, N. C.; Drake, R. P.; Kuranz, C. C.; MacDonald, M. J.; Wan, W. C.; Koenig, M.; Pelka, A.; Ravasio, A.; Yurchak, R.; Kuramitsu, Y.; Sakawa, Y.; Park, H.-S.; Reville, B.; Miniati, F.; Schekochihin, A. A.; Lamb, D. Q.; Gregori, G.

    2015-11-01

    Turbulence and magnetic fields are ubiquitous in the universe. In galaxy clusters, turbulence is believed to amplify seed magnetic fields to values of a few μG, as observed through diffuse radio-synchrotron emission and Faraday rotation measurements. In this study we present experiments that emulate such a process in a controlled laboratory environment. Two laser-driven plasma flows collide to mimic the dynamics of a cluster merger. From the measured density fluctuations we infer the development of Kolmogorov-like turbulence. Measurements of the magnetic field show it is amplified by turbulent motions, reaching a non-linear regime that is a precursor to turbulent dynamo. We also present numerical simulations with the FLASH code that model these experiments. The simulations reproduce the measured plasma properties and enable us to disentangle and characterize the complex physical processes that occur in the experiment. This study provides a promising experimental platform to probe magnetic field amplification by turbulence in plasmas, a process thought to occur in many astrophysical phenomena.

  2. Neutralino dark matter in minimal supergravity: Direct detection versus collider searches

    SciTech Connect

    Baer, H.; Brhlik, M.

    1998-01-01

    We calculate expected event rates for direct detection of relic neutralinos as a function of parameter space of the minimal supergravity model. Numerical results are presented for the specific case of a {sup 73}Ge detector. We find significant detection rates (R{gt}0.01events/kg/day) in regions of parameter space most favored by constraints from B{r_arrow}X{sub s}{gamma} and the cosmological relic density of neutralinos. The detection rates are especially large in regions of large tan{beta}, where many conventional signals for supersymmetry at collider experiments are difficult to detect. If the parameter tan{beta} is large, then there is a significant probability that the first direct evidence for supersymmetry could come from direct detection experiments, rather than from collider searches for sparticles. {copyright} {ital 1997} {ital The American Physical Society}

  3. Search of strangelets and “forward” physics on the collider

    NASA Astrophysics Data System (ADS)

    Kurepin, A. B.

    2016-01-01

    A new stage of the collider experiments at the maximum energy of protons and nuclei at the LHC may lead to the discovery of new phenomena, as well as to confirm the effects previously observed only at very high energies in cosmic rays. A specific program of the experiments is so-called “forward” physics, i.e. the study of low-angle processes. Of the most interesting phenomena can be noted the detection in cosmic rays events called Centauro, which could be explained as the strangelets production. Centauro represent events with small multiplicity and with a strong suppression of electromagnetic component. Since the energy of the beams at the collider and kinematic parameters of the forward detectors CASTOR (CMS), TOTEM, LHCf and the ADA and ADC (ALICE) are close to the parameters and energies of abnormal events in cosmic rays, it is possible to reproduce and investigate in details these events in the laboratory.

  4. Muon colliders: New prospects for precision physics and the high energy frontier

    SciTech Connect

    King, B.J.

    1998-06-01

    An overview is given of muon collider technology and of the current status of the muon collider research program. The exciting potential of muon colliders for both neutrino physics and collider physics studies is then described and illustrated using self-consistent collider parameter sets at 0.1 TeV to 100 TeV center-of-mass energies.

  5. Model SSC (Superconducting Super Collider) dipole magnet cryostat assembly at Fermilab

    SciTech Connect

    Niemann, R.C.

    1989-03-01

    The Superconducting Super Collider (SSC) magnet development program includes the design, fabrication and testing of full length model dipole magnets. A result of the program has been the development of a magnet cryostat design. The cryostat subsystems consist of cold mass connection-slide, suspension, thermal shields, insulation, vacuum vessel and interconnections. Design details are presented along with model magnet production experience. 6 refs., 13 figs.

  6. Probing neutral gauge boson self-interactions in ZZ production at hadron colliders

    NASA Astrophysics Data System (ADS)

    Baur, U.; Rainwater, D.

    2000-12-01

    A detailed analysis of ZZ production at the upgraded Fermilab Tevatron and the CERN Large Hadron Collider is presented for general ZZZ and ZZγ couplings. Deviations from the standard model gauge theory structure for each of these can be parametrized in terms of two form factors which are severely restricted by unitarity at high energy. Achievable limits on these couplings are shown to be a dramatic improvement over the limits currently obtained by e+e- experiments.

  7. SDA-based diagnostic and analysis tools for Collider Run II

    SciTech Connect

    Bolshakov, T.B.; Lebrun, P.; Panacek, S.; Papadimitriou, V.; Slaughter, J.; Xiao, A.; /Fermilab

    2005-05-01

    Operating and improving the understanding of the Fermilab Accelerator Complex for the colliding beam experiments requires advanced software methods and tools. The Shot Data Analysis (SDA) has been developed to fulfill this need. Data from the Fermilab Accelerator Complex is stored in a relational database, and is served to programs and users via Web-based tools. Summary tables are systematically generated during and after a store. These tables (the Supertable, the Recomputed Emittances, the Recomputed Intensities and other tables) are discussed here.

  8. e-A PHYSICS AT A COLLIDER.

    SciTech Connect

    G. T. GARVEY

    2001-01-09

    An electron-nucleus (e-A) collider with center-of-mass energy in excess of 50 GeV per electron-nucleon collision will allow the physics community to obtain unprecedented new knowledge of the partonic structure of nuclei. If reliable information is to be extracted on these partonic densities, it is essential to realize that with our current level of understanding of QCD, momentum transfers to the struck partons greater than 1 GeV/c are necessary. This requirement puts a priority on high center-of-mass energy if partonic densities are to be measured over a wide range. Comparing the partonic structure of the free nucleon to that of bound nucleons and measuring the systematic changes in that structure as a function of nucleon number (A) will provide deeper insight into the origins and dynamics of nuclear binding. In addition, e-A collisions will allow the exploration of partonic densities appreciably higher than is accessible in e-p collisions. An e-A collider will allow one to measure the gluonic structure functions of nuclei down to x {approx} 10{sup -3}, information valuable in its own right and essential to a quantitative understanding of highly relativistic A-A collisions. The time-space evolution of partons can only be investigated by studying the modifications of hard collisions that take place when nuclear targets are employed. In a hard collision the partonic fragments interact, hadronize, and reinteract on their way to the distant detectors without revealing their evolution into the hadrons finally detected. Nuclear targets of differing A place varying amounts of nuclear matter in proximity to the hard collision producing unique information about the quantum fluctuations of incident projectile prior to the collision and on the early evolution of the produced partons. Using charged leptons (e, {mu}) to investigate this physics has been the richest source of information to date and extending the reach of these investigations by the constructing an e -A collider

  9. Multianode Photomultiplier Tube Alignment for the MINERvA Experiment at Fermilab

    NASA Astrophysics Data System (ADS)

    Bruno, Jorge

    2006-10-01

    The MINERvA experiment (Main INjector ExpeRiment vA) at FNAL will study the neutrino-nucleon and neutrino-nucleus interaction. The light collection from the detector will be done via optic fibers using Hamamatsu H8804 64-channel photomultiplier tubes (PMT). Each PMT channel needs to be precisely aligned with the corresponding optic fiber. The MINERvA PMT optical boxes contain precision machined optic ``cookies'' which capture the 8x8 array of optic fibers. Each PMT-cookie pair needs to be aligned as precisely as possible. This contribution will describe the alignment setup and procedure implemented at James Madison University.

  10. Colliding superposed waves in the Einstein-Maxwell theory

    SciTech Connect

    Halilsoy, M.

    1989-04-15

    We reformulate the initial data on the characteristic surface for colliding waves in the Einstein-Maxwell theory. This approach takes into account the superposition principle for gravitational and electromagnetic waves. Finding exact solutions for colliding superposed waves happens to be a rather challenging problem.

  11. Design considerations for a laser-plasma linear collider

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Geddes, C. G. R.; Toth, Cs.; Leemans, W. P.

    2009-01-22

    Design considerations for a next-generation electron-positron linear collider based on laser-plasma-accelerators are discussed. Several of the advantages and challenges of laser-plasma-based accelerator technology are addressed. An example of the parameters for a 1 TeV laser-plasma-based collider is presented.

  12. Event simulation for colliders — A basic overview

    NASA Astrophysics Data System (ADS)

    Reuschle, Christian

    2015-05-01

    In this article we will discuss the basic calculational concepts to simulate particle physics events at high energy colliders. We will mainly focus on the physics in hadron colliders and particularly on the simulation of the perturbative parts, where we will in turn focus on the next-to-leading order QCD corrections.

  13. The Threshold of Embedded M Collider Bias and Confounding Bias

    ERIC Educational Resources Information Center

    Kelcey, Benjamin; Carlisle, Joanne

    2011-01-01

    Of particular import to this study, is collider bias originating from stratification on retreatment variables forming an embedded M or bowtie structural design. That is, rather than assume an M structural design which suggests that "X" is a collider but not a confounder, the authors adopt what they consider to be a more reasonable position and…

  14. Implementation of Stochastic Cooling Hardware at Fermilab's Tevatron Collider

    SciTech Connect

    Pasquinelli, Ralph J.; /Fermilab

    2011-08-01

    The invention of Stochastic cooling by Simon van der Meer made possible the increase in phase space density of charged particle beams. In particular, this feedback technique allowed the development of proton antiproton colliders at both CERN and Fermilab. This paper describes the development of hardware systems necessary to cool antiprotons at the Fermilab Tevatron Collider complex.

  15. Implementation of stochastic cooling hardware at Fermilab's Tevatron collider

    NASA Astrophysics Data System (ADS)

    Pasquinelli, Ralph J.

    2011-08-01

    The invention of Stochastic cooling by Simon van der Meer made possible the increase in phase space density of charged particle beams. In particular, this feedback technique allowed the development of proton antiproton colliders at both CERN and Fermilab. This paper describes the development of hardware systems necessary to cool antiprotons at the Fermilab Tevatron Collider complex.

  16. Design considerations for a laser-plasma linear collider

    SciTech Connect

    Schroeder, C. B.; Esarey, E.; Geddes, C. G. R.; Toth, Cs.; Leemans, W. P.

    2008-08-01

    Design considerations for a next-generation electron-positron linear collider based on laser-plasma-accelerators are discussed. Several of the advantages and challenges of laser-plasma based accelerator technology are addressed. An example of the parameters for a 1 TeV laser-plasma based collider is presented.

  17. RF power generation for future linear colliders

    SciTech Connect

    Fowkes, W.R.; Allen, M.A.; Callin, R.S.; Caryotakis, G.; Eppley, K.R.; Fant, K.S.; Farkas, Z.D.; Feinstein, J.; Ko, K.; Koontz, R.F.; Kroll, N.; Lavine, T.L.; Lee, T.G.; Miller, R.H.; Pearson, C.; Spalek, G.; Vlieks, A.E.; Wilson, P.B.

    1990-06-01

    The next linear collider will require 200 MW of rf power per meter of linac structure at relatively high frequency to produce an accelerating gradient of about 100 MV/m. The higher frequencies result in a higher breakdown threshold in the accelerating structure hence permit higher accelerating gradients per meter of linac. The lower frequencies have the advantage that high peak power rf sources can be realized. 11.42 GHz appears to be a good compromise and the effort at the Stanford Linear Accelerator Center (SLAC) is being concentrated on rf sources operating at this frequency. The filling time of the accelerating structure for each rf feed is expected to be about 80 ns. Under serious consideration at SLAC is a conventional klystron followed by a multistage rf pulse compression system, and the Crossed-Field Amplifier. These are discussed in this paper.

  18. Beam dynamics issues in linear colliders

    SciTech Connect

    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 effects 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.

  19. Small air showers and collider physics

    NASA Technical Reports Server (NTRS)

    Capdevielle, J. N.; Gawin, J.; Grochalska, B.

    1985-01-01

    At energies lower than 2.5 X 10 to the 5 GeV (in Lab. system), more accurate information on nucleon-nucleon collision (p-p collider and on primary composition now exist. The behavior of those both basic elements in cosmic ray phenomenology from ISR energy suggests some tendencies for reasonable extrapolation in the next decade 2.0x10 to the 5 to 2.0x10 to the 6 GeV. Small showers in altitude, recorded in the decade 2 X 10 to the 4 to 2 X 10 to the 5 GeV offers a good tool to testify the validity of all the Monte-Carlo simulation analysis and appreciate how nucleon-air collision are different from nucleon-nucleon collisions.

  20. Galaxies Collide to Create Hot, Huge Galaxy

    NASA Technical Reports Server (NTRS)

    2009-01-01

    This image of a pair of colliding galaxies called NGC 6240 shows them in a rare, short-lived phase of their evolution just before they merge into a single, larger galaxy. The prolonged, violent collision has drastically altered the appearance of both galaxies and created huge amounts of heat turning NGC 6240 into an 'infrared luminous' active galaxy.

    A rich variety of active galaxies, with different shapes, luminosities and radiation profiles exist. These galaxies may be related astronomers have suspected that they may represent an evolutionary sequence. By catching different galaxies in different stages of merging, a story emerges as one type of active galaxy changes into another. NGC 6240 provides an important 'missing link' in this process.

    This image was created from combined data from the infrared array camera of NASA's Spitzer Space Telescope at 3.6 and 8.0 microns (red) and visible light from NASA's Hubble Space Telescope (green and blue).

  1. QCD and jets at hadron colliders

    NASA Astrophysics Data System (ADS)

    Sapeta, Sebastian

    2016-07-01

    We review various aspects of jet physics in the context of hadron colliders. We start by discussing the definitions and properties of jets and recent development in this area. We then consider the question of factorization for processes with jets, in particular for cases in which jets are produced in special configurations, like for example in the region of forward rapidities. We review numerous perturbative methods for calculating predictions for jet processes, including the fixed-order calculations as well as various matching and merging techniques. We also discuss the questions related to non-perturbative effects and the role they play in precision jet studies. We describe the status of calculations for processes with jet vetoes and we also elaborate on production of jets in forward direction. Throughout the article, we present selected comparisons between state-of-the-art theoretical predictions and the data from the LHC.

  2. Illuminating new electroweak states at hadron colliders

    NASA Astrophysics Data System (ADS)

    Ismail, Ahmed; Izaguirre, Eder; Shuve, Brian

    2016-07-01

    In this paper, we propose a novel powerful strategy to perform searches for new electroweak states. Uncolored electroweak states appear in generic extensions of the Standard Model (SM) and yet are challenging to discover at hadron colliders. This problem is particularly acute when the lightest state in the electroweak multiplet is neutral and all multiplet components are approximately degenerate. In this scenario, production of the charged fields of the multiplet is followed by decay into nearly invisible states; if this decay occurs promptly, the only way to infer the presence of the reaction is through its missing energy signature. Our proposal relies on emission of photon radiation from the new charged states as a means of discriminating the signal from SM backgrounds. We demonstrate its broad applicability by studying two examples: a pure Higgsino doublet and an electroweak quintuplet field.

  3. 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.

  4. A proof of the conformal collider bounds

    NASA Astrophysics Data System (ADS)

    Hofman, Diego M.; Li, Daliang; Meltzer, David; Poland, David; Rejon-Barrera, Fernando

    2016-06-01

    In this paper, we prove that the "conformal collider bounds" originally proposed in [1] hold for any unitary parity-preserving conformal field theory (CFT) with a unique stress tensor in dimensions d ≥ 3. In particular this implies that the ratio of central charges for a unitary 4d CFT lies in the interval 31/18ge a/cge 1/3 . For superconformal theories this is further reduced to 3/2ge a/cge 1/2 . The proof relies only on CFT first principles — in particular, bootstrap methods — and thus constitutes the first complete field theory proof of these bounds. We further elaborate on similar bounds for non-conserved currents and relate them to results obtained recently from deep inelastic scattering.

  5. Ground motion data for International Collider models

    SciTech Connect

    Volk, J.T.; LeBrun, P.; Shiltsev, V.; Singatulin, S.; /Fermilab

    2007-11-01

    The proposed location for the International Linear Collider (ILC) in the Americas region is Fermilab in Batavia Illinois. If built at this location the tunnels would be located in the Galena Platteville shale at a depth of 100 or more meters below the surface. Studies using hydro static water levels and seismometers have been conducted in the MINOS hall and the LaFrange Mine in North Aurora Illinois to determine the level of ground motion. Both these locations are in the Galena Platteville shale and indicate the typical ground motion to be expected for the ILC. The data contains both natural and cultural noise. Coefficients for the ALT law are determined. Seismic measurements at the surface and 100 meters below the surface are presented.

  6. Beam Dynamics Considerations in Electron Ion Colliders

    NASA Astrophysics Data System (ADS)

    Krafft, Geoffrey

    2015-04-01

    The nuclear physics community is converging on the idea that the next large project after FRIB should be an electron-ion collider. Both Brookhaven National Lab and Thomas Jefferson National Accelerator Facility have developed accelerator designs, both of which need novel solutions to accelerator physics problems. In this talk we discuss some of the problems that must be solved and their solutions. Examples in novel beam optics systems, beam cooling, and beam polarization control will be presented. Authored by Jefferson Science Associates, LLC under U.S. DOE Contract No. DE-AC05-06OR23177. The U.S. Government retains a non-exclusive, paid-up, irrevocable, world-wide license to publish or reproduce this manuscript for U.S. Government purposes.

  7. Colliding Beam Fusion Reactor Space Propulsion System

    NASA Astrophysics Data System (ADS)

    Cheung, A.; Binderbauer, M.; Liu, F.; Qerushi, A.; Rostoker, N.; Wessel, F. J.

    2004-02-01

    The Colliding Beam Fusion Reactor Space Propulsion System, CBFR-SPS, is an aneutronic, magnetic-field-reversed configuration, fueled by an energetic-ion mixture of hydrogen and boron11 (H-B11). Particle confinement and transport in the CBFR-SPS are classical, hence the system is scaleable. Fusion products are helium ions, α-particles, expelled axially out of the system. α-particles flowing in one direction are decelerated and their energy recovered to ``power'' the system; particles expelled in the opposite direction provide thrust. Since the fusion products are charged particles, the system does not require the use of a massive-radiation shield. This paper describes a 100 MW CBFR-SPS design, including estimates for the propulsion-system parameters and masses. Specific emphasis is placed on the design of a closed-cycle, Brayton-heat engine, consisting of heat-exchangers, turbo-alternator, compressor, and finned radiators.

  8. Time resolved diagnostics of ions in colliding carbon plasmas

    SciTech Connect

    Singh, Ravi Pratap; Gupta, Shyam L.; Thareja, Raj K.

    2014-11-14

    We report a comparative study of the dynamic behaviour of ions at different pressures in laser ablated colliding and single plasma plumes using 2D imaging, optical emission spectroscopy (OES) and a retarding field analyser (RFA). 2D imaging shows the splitting of plasma plumes due to different velocities of various plasma species. OES shows enhancement in abundance of ionic species with their presence for a longer time in colliding plume. C{sub 2} molecular formation is seen at later time in colliding plume compared to single plume and is attributed to dominating collisional processes in the colliding region of the plumes. The time of flight distribution of ions traced by the RFA shows the variation with change in fluence as well as ambient pressure for both colliding and single plume. Time of flight analysis of ions also shows the appearance of a fast peak in ion signal due to acceleration of ions at larger fluence.

  9. The Relativistic Heavy Ion Collider control system

    SciTech Connect

    Clifford, T.S.; Barton, D.S.; Oerter, B.R.

    1997-12-01

    The Relativistic Heavy Ion Collider control system has been used in the commissioning of the AGS to RHIC transfer line and in the first RHIC sextant test. Much of the controls infrastructure for networks and links has been installed throughout the collider. All of the controls hardware modules needed to be built for early RHIC operations have been designed and tested. Many of these VME modules are already being used in normal AGS operations. Over 150 VME based front end computers and device controllers will be installed by the Summer of 1998 in order to be ready for Fall of 1998. A few features are being added to the front end computer core software. The bulk of the Accelerator Device Objects (ADOs) which are instantiated in the FECs, have been written and tested in the early commissioning. A configuration database has been designed. Generic control and display of ADO parameters via a spreadsheet like program on the console level computers was provided early on in the control system development. User interface tools that were developed for the AGS control system have been used in RHIC applications. Some of the basic operations programs, like alarm display and save/restore, that are used in the AGS operations have been or will be expanded to support RHIC operations. A model for application programs which involves a console level manager servicing ADOs have been verified with a few RHIC applications. More applications need to be written for the Fall of 1998 commissioning effort. A sequencer for automatic control of the fill is being written with the expectation that it will be useful in early commissioning.

  10. Linear Collider Flavour Identification status report: Sensors for the International Linear Collider

    NASA Astrophysics Data System (ADS)

    Stefanov, K. D.

    2007-12-01

    The Linear Collider Flavour Identification (LCFI) collaboration is continuing the work to develop column-parallel CCDs (CPCCD) and CMOS readout chips to be used in the vertex detector at the international linear collider (ILC). The CPCCD achieves several orders of magnitude faster readout than conventional CCDs because every column is equipped with amplifier and ADC, enabling efficient data taking with low occupancy. Already two generations of CPCCDs and readout chips have been manufactured and the first chips have been fully tested. The second generation devices are now being evaluated. A new CCD-based device, the in-situ storage image sensor (ISIS) has also been developed. The ISIS offers numerous advantages in terms of relaxed readout, increased radiation hardness and great immunity to EMI. In this paper we present the results from the tests of the CPCCDs, readout chips and ISIS, as well as the plans for future developments.

  11. Detectors for Linear Colliders: Calorimetry at a Future Electron-Positron Collider (3/4)

    SciTech Connect

    2010-02-17

    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.

  12. Detectors for Linear Colliders: Calorimetry at a Future Electron-Positron Collider (3/4)

    ScienceCinema

    None

    2011-10-06

    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.

  13. Status and future directions for advanced accelerator research - conventional and non-conventional collider concepts

    SciTech Connect

    Siemann, R.H.

    1997-01-01

    The relationship between advanced accelerator research and future directions for particle physics is discussed. Comments are made about accelerator research trends in hadron colliders, muon colliders, and e{sup +}3{sup {minus}} linear colliders.

  14. Beam tube vacuum in future superconducting proton colliders

    SciTech Connect

    Turner, W.

    1994-10-01

    The beam tube vacuum requirements in future superconducting proton colliders that have been proposed or discussed in the literature -- SSC, LHC, and ELN -- are reviewed. The main beam tube vacuum problem encountered in these machines is how to deal with the magnitude of gas desorption and power deposition by synchrotron radiation while satisfying resistivity, impedance, and space constraints in the cryogenic environment of superconducting magnets. A beam tube vacuum model is developed that treats photodesorption of tightly bound H, C, and 0, photodesorption of physisorbed molecules, and the isotherm vapor pressure of H{sub 2}. Experimental data on cold tube photodesorption experiments are reviewed and applied to model calculations of beam tube vacuum performance for simple cold beam tube and liner configurations. Particular emphasis is placed on the modeling and interpretation of beam tube photodesorpiion experiments at electron synchrotron light sources. The paper also includes discussion of the constraints imposed by beam image current heating, the growth rate of the resistive wall instability, and single-bunch instability impedance limits.

  15. A tevatron collider beauty factory. [Final report, 1980--1992

    SciTech Connect

    Not Available

    1992-12-31

    This document which is labeled a final report consists of several different items. The first is a proposal for a detector to be developed for beauty physics. The detector is proposed for the Fermilab Tevatron, and would be designed to measure mixing reactions, rare decay modes, and even CP violation in hadron collider beauty production. The general outline of the work proposed is given, and an estimate of the time to actually design the detector is presented, along with proposed changes to the Tevatron to accommodate the system. A preliminary report on an experiment to verify a reported observation of a 17 keV neutrino in tritium decay is presented. The present results in the decay spectra actually show a depression below expected levels, which is not consistent with a massive neutrino. Additional interest has been shown in finishing an electrostatic beta spectrometer which was started several years previously. The instrument uses hemispherical electrostatic electric fields to retard electrons emitted in tritium decay, allowing measurement of integral spectra. The design goal has a 5 eV energy resolution, which may be achievable. A new PhD student is pursuing this experiment. Also the report contains a proposal for additional work in the field of non-perturbative quantum field theory by the theoretical group at OU. The work which is proposed will be applied to electroweak and strong interactions, as well as to quantum gravitational phenomena.

  16. Beam tube vacuum in future superconducting proton colliders

    NASA Astrophysics Data System (ADS)

    Turner, William C.

    1995-02-01

    The beam tube vacuum requirements in future superconducting proton colliders that have been proposed or discussed in the literature—SSC, LHC, and ELN—are reviewed. The main beam tube vacuum problem encountered in these machines is how to deal with the magnitude of gas desorption and power deposition by synchrotron radiation while satisfying resistivity, impedance, and space constraints in the cryogenic environment of superconducting magnets. A beam tube vacuum model is developed that treats photodesorption of tightly bound H, C, and O, photodesorption of physisorbed molecules, and the isotherm vapor pressure of H2. Experimental data on cold tube photodesorption experiments are reviewed and applied to model calculations of beam tube vacuum performance for simple cold beam tube and liner configurations. Particular emphasis is placed on the modeling and interpretation of beam tube photodesorption experiments at electron synchrotron light sources. The paper also includes discussion of the constraints imposed by beam image current heating, the growth rate of the resistive wall instability, and single-bunch instability impedance limits.

  17. Collider Detector at Fermilab (CDF): Data from Standard Model and Supersymmetric Higgs Bosons Research of the Higgs Group

    DOE Data Explorer

    The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The Higgs group searches for Standard Model and Supersymmetric Higgs bosons. Their public web page makes data and numerous figures available from both CDF Runs I and II.

  18. Collider Detector at Fermilab (CDF): Data from the QCD Group's Research into Properties of the Strong Interaction

    DOE Data Explorer

    ,

    The Collider Detector at Fermilab (CDF) is a Tevatron experiment at Fermilab. The Tevatron, a powerful particle accelerator, accelerates protons and antiprotons close to the speed of light, and then makes them collide head-on inside the CDF detector. The CDF detector is used to study the products of such collisions. The CDF Physics Group at Fermilab is organized into six working groups, each with a specific focus. The QCD group studies the properties of the strong interaction. Their public web page makes data and numerous figures available from both CDF Runs I and II.

  19. Studies of Magnetic Reconnection in Colliding Laser-Produced Plasmas

    NASA Astrophysics Data System (ADS)

    Rosenberg, Michael

    2013-10-01

    Novel images of magnetic fields and measurements of electron and ion temperatures have been obtained in the magnetic reconnection region of high- β, laser-produced plasmas. Experiments using laser-irradiated foils produce expanding, hemispherical plasma plumes carrying MG Biermann-battery magnetic fields, which can be driven to interact and reconnect. Thomson-scattering measurements of electron and ion temperatures in the interaction region of two colliding, magnetized plasmas show no thermal enhancement due to reconnection, as expected for β ~ 8 plasmas. Two different proton radiography techniques used to image the magnetic field structures show deformation, pileup, and annihilation of magnetic flux. High-resolution images reveal unambiguously reconnection-induced jets emerging from the interaction region and show instabilities in the expanding plasma plumes and supersonic, hydrodynamic jets due to the plasma collision. Quantitative magnetic flux data show that reconnection in experiments with asymmetry in the scale size, density, temperature, and plasma flow across the reconnection region occurs less efficiently than in similar, symmetric experiments. This result is attributed to disruption of the Hall mechanism mediating collisionless reconnection. The collision of plasmas carrying parallel magnetic fields has also been probed, illustrating the deformation of magnetic field structures in high-energy-density plasmas in the absence of reconnection. These experiments are particularly relevant to high- β reconnection environments, such as the magnetopause. This work was performed in collaboration with C. Li, F. Séguin, A. Zylstra, H. Rinderknecht, H. Sio, J. Frenje, and R. Petrasso (MIT), I. Igumenshchev, V. Glebov, C. Stoeckl, and D. Froula (LLE), J. Ross and R. Town (LLNL), W. Fox (UNH), and A. Nikroo (GA), and was supported in part by the NLUF, FSC/UR, U.S. DOE, LLNL, and LLE.

  20. Alighment and Vibration Issues in TeV Linear Collider Design

    SciTech Connect

    Fischer, G.E.; /SLAC

    2005-08-12

    The next generation of linear colliders will require alignment accuracies and stabilities of component placement at least one, perhaps two, orders of magnitude better than can be achieved by the conventional methods and procedures in practice today. The magnitudes of these component-placement tolerances for current designs of various linear collider subsystems are tabulated. In the micron range, long-term ground motion is sufficiently rapid that on-line reference and mechanical correction systems are called for. Some recent experiences with the upgraded SLAC laser alignment systems and examples of some conceivable solutions for the future are described. The so called ''girder'' problem is discussed in the light of ambient and vibratory disturbances. The importance of the quality of the underlying geology is stressed. The necessity and limitations of particle-beam-derived placement information are mentioned.

  1. Alignment and vibration issues in TeV linear collider design

    SciTech Connect

    Fischer, G.E.

    1989-07-01

    The next generation of linear colliders will require alignment accuracies and stabilities of component placement at least one, perhaps two, orders of magnitude better than can be achieved by the conventional methods and procedures in practice today. The magnitudes of these component-placement tolerances for current designs of various linear collider subsystems are tabulated. In the micron range, long-term ground motion is sufficiently rapid that on-line reference and mechanical correction systems are called for. Some recent experiences with the upgraded SLAC laser alignment systems and examples of some conceivable solutions for the future are described. The so called ''girder'' problem is discussed in the light of ambient and vibratory disturbances. The importance of the quality of the underlying geology is stressed. The necessity and limitations of public-beam-derived placement information are mentioned. 40 refs., 4 figs., 1 tab.

  2. Probing charged Higgs boson couplings at a future circular hadron collider

    NASA Astrophysics Data System (ADS)

    Ćakır, I. T.; Kuday, S.; Saygın, H.; Şenol, A.; ćakır, O.

    2016-07-01

    Many of the new physics models predict a light Higgs boson similar to the Higgs boson of the Standard Model (SM) and also extra scalar bosons. Beyond the search channels for a SM Higgs boson, the future collider experiments will explore additional channels that are specific to extended Higgs sectors. We study the charged Higgs boson production within the framework of two Higgs doublet models (THDM) in the proton-proton collisions at a future circular hadron collider (FCC-hh). With an integrated luminosity of Lint=500 fb-1 at very high energy frontier (√{s }=100 TeV ), we obtain a significant coverage of the parameter space and distinguish the charged Higgs-top-bottom interaction within the THDM or other new physics models with charged Higgs boson mass up to 1.5 TeV.

  3. DEPFET Active Pixel Detectors for a Future Linear e(+}e({-)) Collider

    NASA Astrophysics Data System (ADS)

    Alonso, O.; Casanova, R.; Dieguez, A.; Dingfelder, J.; Hemperek, T.; Kishishita, T.; Kleinohl, T.; Koch, M.; Kruger, H.; Lemarenko, M.; Lutticke, F.; Marinas, C.; Schnell, M.; Wermes, N.; Campbell, A.; Ferber, T.; Kleinwort, C.; Niebuhr, C.; Soloviev, Y.; Steder, M.; Volkenborn, R.; Yaschenko, S.; Fischer, P.; Kreidl, C.; Peric, I.; Knopf, J.; Ritzert, M.; Curras, E.; Lopez-Virto, A.; Moya, D.; Vila, I.; Boronat, M.; Esperante, D.; Fuster, J.; Garcia, I. Garcia; Lacasta, C.; Oyanguren, A.; Ruiz, P.; Timon, G.; Vos, M.; Gessler, T.; Kuhn, W.; Lange, S.; Munchow, D.; Spruck, B.; Frey, A.; Geisler, C.; Schwenker, B.; Wilk, F.; Barvich, T.; Heck, M.; Heindl, S.; Lutz, O.; Muller, Th.; Pulvermacher, C.; Simonis, H. J.; Weiler, T.; Krausser, T.; Lipsky, O.; Rummel, S.; Schieck, J.; Schluter, T.; Ackermann, K.; Andricek, L.; Chekelian, V.; Chobanova, V.; Dalseno, J.; Kiesling, C.; Koffmane, C.; Gioi, L. Li; Moll, A.; Moser, H. G.; Muller, F.; Nedelkovska, E.; Ninkovic, J.; Petrovics, S.; Prothmann, K.; Richter, R.; Ritter, A.; Ritter, M.; Simon, F.; Vanhoefer, P.; Wassatsch, A.; Dolezal, Z.; Drasal, Z.; Kodys, P.; Kvasnicka, P.; Scheirich, J.

    2013-04-01

    The DEPFET collaboration develops highly granular, ultra-transparent active pixel detectors for high-performance vertex reconstruction at future collider experiments. The characterization of detector prototypes has proven that the key principle, the integration of a first amplification stage in a detector-grade sensor material, can provide a comfortable signal to noise ratio of over 40 for a sensor thickness of 50-75 $\\mathrm{\\mathbf{\\mu m}}$. ASICs have been designed and produced to operate a DEPFET pixel detector with the required read-out speed. A complete detector concept is being developed, including solutions for mechanical support, cooling and services. In this paper the status of DEPFET R & D project is reviewed in the light of the requirements of the vertex detector at a future linear $\\mathbf{e^+ e^-}$ collider.

  4. Tevatron Collider Run II status and novel technologies for luminosity upgrades

    SciTech Connect

    Vladimir Shiltsev

    2004-07-20

    Over the past 2 years the Tevatron peak luminosity steadily progressed and reached the level of 92e30 cm-2s-1 which exceeds the original Run IIa goal. Over 0.57fb-1 have being delivered to each CDF and D0 experiments since the beginning of the Run II. In parallel to the Collider operation, we have started a project of the luminosity upgrade which should lead to peak luminosities of about 270e30 and total integrated luminosity of 4.4-8.5 fb-1 through FY2009. In this paper we describe the status of the Tevatron Collider complex, essence of the upgrades and novel accelerator technologies to be employed.

  5. Linear collider signals of an invisible Higgs boson in theories of large extra dimensions

    SciTech Connect

    Datta, Anindya; Huitu, Katri; Laamanen, Jari; Mukhopadhyaya, Biswarup

    2004-10-01

    We discuss the possibility of detecting a Higgs boson in electron-positron collider experiments if large extra dimensions are realized in nature. In such a case, the Higgs boson can decay invisibly by oscillating into a graviscalar Kaluza-Klein tower. We show that the search for such a Higgs boson at an e{sup +}e{sup -} linear collider entails more complications than are usually thought of in relation to an invisibly decaying Higgs boson. The main sources of such complications are due to the simultaneous presence of a continuum graviton production and the broadening of the Higgs peak. We discuss possible ways of overcoming such difficulties and conclude that the detection of such a Higgs boson might still be a problem beyond the mass range of 250-300 GeV.

  6. Beam induced backgrounds: CDF experience

    SciTech Connect

    Tesarek, R.J.; /Fermilab

    2008-05-01

    We summarize the experiences of the Collider Detector at Fermilab (CDF) experiment in the presence of backgrounds originating from the counter circulating beams in the Fermilab Tevatron. These backgrounds are measured and their sources identified. Finally, we outline the strategies employed to reduce the effects of these backgrounds on the experiment.

  7. Run scenarios for the linear collider

    SciTech Connect

    M. Battaglia et al.

    2002-12-23

    We have examined how a Linear Collider program of 1000 fb{sup -1} could be constructed in the case that a very rich program of new physics is accessible at {radical}s {le} 500 GeV. We have examined possible run plans that would allow the measurement of the parameters of a 120 GeV Higgs boson, the top quark, and could give information on the sparticle masses in SUSY scenarios in which many states are accessible. We find that the construction of the run plan (the specific energies for collider operation, the mix of initial state electron polarization states, and the use of special e{sup -}e{sup -} runs) will depend quite sensitively on the specifics of the supersymmetry model, as the decay channels open to particular sparticles vary drastically and discontinuously as the underlying SUSY model parameters are varied. We have explored this dependence somewhat by considering two rather closely related SUSY model points. We have called for operation at a high energy to study kinematic end points, followed by runs in the vicinity of several two body production thresholds once their location is determined by the end point studies. For our benchmarks, the end point runs are capable of disentangling most sparticle states through the use of specific final states and beam polarizations. The estimated sparticle mass precisions, combined from end point and scan data, are given in Table VIII and the corresponding estimates for the mSUGRA parameters are in Table IX. The precision for the Higgs boson mass, width, cross-sections, branching ratios and couplings are given in Table X. The errors on the top quark mass and width are expected to be dominated by the systematic limits imposed by QCD non-perturbative effects. The run plan devotes at least two thirds of the accumulated luminosity near the maximum LC energy, so that the program would be sensitive to unexpected new phenomena at high mass scales. We conclude that with a 1 ab{sup -1} program, expected to take the first 6-7 years

  8. Multi-waveband observations of colliding galaxies

    NASA Technical Reports Server (NTRS)

    Appleton, P. N.; Robson, E. I.; Schombert, James M.

    1990-01-01

    Colliding galaxies represent a major challenge to both theorists and observers because of the large variety of phenomena which are expected to come into play during the interaction. Strong gravitational fluctuations may drive non-linear waves and instabilities throughout the stars and gas leading to enhanced star formation, nuclear activity and ultimately a mixing of the morphological components of the original galaxies. One relatively uncomplicated class of colliding galaxy where stellar waves play an important role in star formation are ring galaxies. Ring galaxies are probably formed when a companion galaxy passes through the center of a disk system driving circular waves through the disk (Lynds and Toomre 1976, Toomre 1978, Struck-Marcell 1990). Off-center collisions can generate non-circular waves and can be loosely described as banana-shaped although they may exhibit more complex forms as the waves expand into the disk. The propagation of such stellar and gaseous waves through the disk leads to enhanced star formation (e.g., Appleton and Struck-Marcell 1987a; Jeske 1986) and provides a unique probe of the response of the interstellar medium (ISM) to a propagating wave (see Appleton and Struck-Marcell 1987b). Here, the authors report results for 3 systems; the irregular ring Arp 143 (=VV 117); Wakamatsu's Seyfert ring (A0959-755; see Wakamatsu and Nishida 1987) and the brighter member of the pair of ring galaxies comprising of AM 1358-221. The most complete multi-wavelength data is for Arp 143. Optical charge coupled device (CCD) observations made with the 60 inch Palomar telescope at BV and r band, near-IR images at J (1.25 microns), H (1.65 microns) and k (2.2 microns) bands from the infrared camera (IRCAM) InSb array camera on the 3.8m United Kingdon Infrared Telescope (UKIRT) telescope and very large array (VLA) observations at 20cm in both the neutral hydrogen line and radio continuum are described. The observations of Wakamatsu's ring and AM 1358 were

  9. Overview of the Tevatron Collider Complex: Goals, Operations and Performance

    SciTech Connect

    Holmes, Stephen; Moore, Ronald S.; Shiltsev, Vladimir

    2011-06-01

    For more than two decades the Tevatron proton-antiproton collider was the centerpiece of the world's high energy physics program. The collider was arguably one of the most complex research instruments ever to reach the operation stage and is widely recognized for numerous physics discoveries and for many technological breakthroughs. In this article we outline the historical background that led to the construction of the Tevatron Collider, the strategy applied to evolution of performance goals over the Tevatron's operational history, and briefly describe operations of each accelerator in the chain and achieved performance.

  10. Beamstrahlung spectra in next generation linear colliders. Revision

    SciTech Connect

    Barklow, T.; Chen, P.; Kozanecki, W.

    1992-04-01

    For the next generation of linear colliders, the energy loss due to beamstrahlung during the collision of the e{sup +}e{sup {minus}} beams is expected to substantially influence the effective center-of-mass energy distribution of the colliding particles. In this paper, we first derive analytical formulae for the electron and photon energy spectra under multiple beamstrahlung processes, and for the e{sup +}e{sup {minus}} and {gamma}{gamma} differential luminosities. We then apply our formulation to various classes of 500 GeV e{sup +}e{sup {minus}} linear collider designs currently under study.

  11. 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.

  12. Heavy flavor production and top quark search at hadron colliders

    SciTech Connect

    Baer, H.A.

    1991-01-01

    We review heavy flavor production at hadron colliders, with an eye towards the physics of the top quark. Motivation for existence of top, and current status of top search are reviewed. The physics of event simulation at hadron colliders is reviewed. We discuss characteristics of top quark events at p{bar p} colliders that may aid in distinguishing the top quark signal from Standard Model backgrounds, and illustrate various cuts which may be useful for top discovery. Top physics at hadron supercolliders is commented upon, as well as top quark mass measurement techniques. 22 refs., 5 figs.

  13. Laser cooling of electron beams for linear colliders

    SciTech Connect

    Telnov, V.

    1996-10-01

    A novel method of electron beam cooling is considered which can be used for linear colliders. The electron beam is cooled during collision with focused powerful laser pulse. With reasonable laser parameters (laser flash energy about 10 J) one can decrease transverse beam emittances by a factor about 10 per one stage. The ultimate transverse emittances are much below that given by other methods. Depolarization of a beam during the cooling is about 5--15% for one stage. This method is especially useful for photon colliders and open new possibilities for e{sup +}e{sup {minus}} colliders and x-ray FEL based on high energy linacs.

  14. Cryostat design for the Superconducting Super Collider

    SciTech Connect

    Nicol, T.H.

    1990-09-01

    The cryostat of an SSC dipole magnet consists of all magnet components except the cold mass assembly. It serves to support the cold mass accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation (MLI) system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course their 25 year expected life. This paper describes the design of the current SSC collider dipole magnet cryostat and includes discussions on the thermal, structural, and dynamic considerations involved in the development of each of the major systems. 7 refs., 4 figs.

  15. Multimegawatt rf power sources for linear colliders

    SciTech Connect

    Caryotakis, G.

    1991-04-01

    Conceptual designs for a future linear collider operating at 11.4 GHz call for peak rf power as high as 240 MW per meter, with an accelerator length of 14 km. This is an extremely high total power, which results in requirements for microwave sources that cannot be met with existing microwave tubes. While some new tube concepts are being considered, work is proceeding at several laboratories in the US and abroad on conventional 100 MW klystrons for this application. The electron beam necessary for this power to be generated, unless carefully controlled, can easily cause intrapulse melting at the klystron output circuit. This, coupled to the need for good efficiency, high production yield, and long life, poses some difficult problems to the klystron designer. Experimental klystrons at SLAC and other laboratories are approaching the goal of 100 MW in 800 nsec pulses, but much work remains to be done before a design is available which is suitable for manufacturing thousands of these tubes. 4 figs., 1 tab.

  16. A large hadron electron collider at CERN

    DOE PAGESBeta

    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

  17. Conformal collider physics from the lightcone bootstrap

    NASA Astrophysics Data System (ADS)

    Li, Daliang; Meltzer, David; Poland, David

    2016-02-01

    We analytically study the lightcone limit of the conformal bootstrap equations for 4-point functions containing global symmetry currents and the stress tensor in 3d CFTs. We show that the contribution of the stress tensor to the anomalous dimensions of large spin double-twist states is negative if and only if the conformal collider physics bounds are satisfied. In the context of AdS/CFT these results indicate a relation between the attractiveness of AdS gravity and positivity of the CFT energy flux. We also study the contribution of non-Abelian conserved currents to the anomalous dimensions of double- twist operators, corresponding to the gauge binding energy of 2-particle states in AdS. We show that the representation of the double-twist state determines the sign of the gauge binding energy if and only if the coefficients appearing in the current 3-point function satisfies a similar bound, which is equivalent to an upper bound on the charge flux asymmetry of the CFT.

  18. Colliding beam fusion reactor space propulsion system

    NASA Astrophysics Data System (ADS)

    Wessel, Frank J.; Binderbauer, Michl W.; Rostoker, Norman; Rahman, Hafiz Ur; O'Toole, Joseph

    2000-01-01

    We describe a space propulsion system based on the Colliding Beam Fusion Reactor (CBFR). The CBFR is a high-beta, field-reversed, magnetic configuration with ion energies in the range of hundreds of keV. Repetitively-pulsed ion beams sustain the plasma distribution and provide current drive. The confinement physics is based on the Vlasov-Maxwell equation, including a Fokker Planck collision operator and all sources and sinks for energy and particle flow. The mean azimuthal velocities and temperatures of the fuel ion species are equal and the plasma current is unneutralized by the electrons. The resulting distribution functions are thermal in a moving frame of reference. The ion gyro-orbit radius is comparable to the dimensions of the confinement system, hence classical transport of the particles and energy is expected and the device is scaleable. We have analyzed the design over a range of 106-109 Watts of output power (0.15-150 Newtons thrust) with a specific impulse of, Isp~106 sec. A 50 MW propulsion system might involve the following parameters: 4-meters diameter×10-meters length, magnetic field ~7 Tesla, ion beam current ~10 A, and fuels of either D-He3,P-B11,P-Li6,D-Li6, etc. .

  19. Macroscopic strings and ``quirks'' at colliders

    NASA Astrophysics Data System (ADS)

    Kang, Junhai; Luty, Markus A.

    2009-11-01

    We consider extensions of the standard model containing additional heavy particles (``quirks'') charged under a new unbroken non-abelian gauge group as well as the standard model. We assume that the quirk mass m is in the phenomenologically interesting range 100 GeV-TeV, and that the new gauge group gets strong at a scale Λ < m. In this case breaking of strings is exponentially suppressed, and quirk production results in strings that are long compared to Λ-1. The existence of these long stable strings leads to highly exotic events at colliders. For 100 eV lsimΛ <~ keV the strings are macroscopic, giving rise to events with two separated quirk tracks with measurable curvature toward each other due to the string interaction. For keV <~ Λ <~ MeV the typical strings are mesoscopic: too small to resolve in the detector, but large compared to atomic scales. In this case, the bound state appears as a single particle, but its mass is the invariant mass of a quirk pair, which has an event-by-event distribution. For MeV <~ Λ <~ m, the strings are microscopic, and the quirks annihilate promptly within the detector. For colored quirks, this can lead to hadronic fireball events with ~ 103 hadrons with energy of order GeV emitted in conjunction with hard decay products from the final annihilation.

  20. Simulating graviton production at hadron colliders

    NASA Astrophysics Data System (ADS)

    de Aquino, Priscila; Hagiwara, Kaoru; Li, Qiang; Maltoni, Fabio

    2011-06-01

    Spin-2 particles and in particular gravitons are predicted in many new physics scenarios at the TeV scale. Depending on the details of models such new states might show up as a continuum, massless particles, or TeV scale resonances. Correspondingly, very different discovery signatures should be exploited, from the search of excesses in events with multi jets and large missing transverse energy, to resonances in weak boson or jet pair productions. We present a very general and flexible implementation in M ad-G raph/M adE vent of spin-2 particles interacting with the standard model particles via the energy momentum tensor, which encompasses all of the most popular TeV scale models featuring gravitons. By merging matrix elements with parton shower, we can generate inclusive samples of graviton + jets at the hadron colliders in several scenarios (ADD, zero-mass graviton and RS). We compare and validate our results against the corresponding next-to-leading order QCD calculations.