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Sample records for linear collider final

  1. Final focus systems for linear colliders

    SciTech Connect

    Erickson, R.A.

    1987-11-01

    The final focus system of a linear collider must perform two primary functions, it must focus the two opposing beams so that their transverse dimensions at the interaction point are small enough to yield acceptable luminosity, and it must steer the beams together to maintain collisions. In addition, the final focus system must transport the outgoing beams to a location where they can be recycled or safely dumped. Elementary optical considerations for linear collider final focus systems are discussed, followed by chromatic aberrations. The design of the final focus system of the SLAC Linear Collider (SLC) is described. Tuning and diagnostics and steering to collision are discussed. Most of the examples illustrating the concepts covered are drawn from the SLC, but the principles and conclusions are said to be generally applicable to other linear collider designs as well. 26 refs., 17 figs. (LEW)

  2. 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.

  3. A final focus system for the Next Linear Collider

    SciTech Connect

    Zimmermann, F.; Brown, K.; Emma, P.; Helm, R.; Irwin, J.; Tenenbaum, P.; Wilson, P.

    1995-06-01

    The final focus of the Next Linear Collider (NLC) demagnifies electron and positron beams of 250--750 GeV energy down to a transverse size of about 2.5 {times} 350 nm{sup 2} at the interaction point (IP). The basic layout, momentum bandwidth, vibration tolerances, wakefield effects, and the tunability of the proposed final focus design are discussed. Also a perspective is given on the crab cavity and on effects of the solenoid field in the interaction region.

  4. Expanded studies of linear collider final focus systems at the Final Focus Test Beam

    SciTech Connect

    Tenenbaum, Peter Gregory

    1995-12-01

    In order to meet their luminosity goals, linear colliders operating in the center-of-mass energy range from 3,50 to 1,500 GeV will need to deliver beams which are as small as a few Manometers tall, with x:y aspect ratios as large as 100. The Final Focus Test Beam (FFTB) is a prototype for the final focus demanded by these colliders: its purpose is to provide demagnification equivalent to those in the future linear collider, which corresponds to a focused spot size in the FFTB of 1.7 microns (horizontal) by 60 manometers (vertical). In order to achieve the desired spot sizes, the FFTB beam optics must be tuned to eliminate aberrations and other errors, and to ensure that the optics conform to the desired final conditions and the measured initial conditions of the beam. Using a combination of incoming-beam diagnostics. beam-based local diagnostics, and global tuning algorithms, the FFTB beam size has been reduced to a stable final size of 1.7 microns by 70 manometers. In addition, the chromatic properties of the FFTB have been studied using two techniques and found to be acceptable. Descriptions of the hardware and techniques used in these studies are presented, along with results and suggestions for future research.

  5. Vibration Stabilization of a Mechanical Model of a X-Band Linear Collider Final Focus Magnet

    SciTech Connect

    Frisch, Josef; Chang, Allison; Decker, Valentin; Doyle, Eric; Eriksson, Leif; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Partridge, Richard; Seryi, Andrei; /SLAC

    2006-09-28

    The small beam sizes at the interaction point of a X-band linear collider require mechanical stabilization of the final focus magnets at the nanometer level. While passive systems provide adequate performance at many potential sites, active mechanical stabilization is useful if the natural or cultural ground vibration is higher than expected. A mechanical model of a room temperature linear collider final focus magnet has been constructed and actively stabilized with an accelerometer based system.

  6. Interactive beam tuning simulator for the SLC (Stanford Linear Collider) final focus

    SciTech Connect

    Ford, W.T.; Kozanecki, W.; Lohse, T.; Servranckx, R.V.

    1989-03-01

    An interface to the DIMAD beam optics computer program enables the operator to perform in simulation the sequence of magnet adjustments that would be used online for tuning the Stanford Linear Collider Final Focus System. The program accepts any input beam matrix from a disk file and presents a menu of magnet adjustments and scan and display options. The results of a ray trace calculation are presented as profiles or envelope plots on the graphics screen. We give results from studies of the optimization of the beam under various input conditions. 11 refs., 4 figs.

  7. 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.

  8. 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.

  9. Optical tuning in the arcs and final focus sections of the Stanford Linear Collider

    SciTech Connect

    Bambade, P.S.

    1989-03-01

    In this thesis, we present the experimental tuning procedures developed for the Arcs and for the Final Focus Section of the Stanford Linear Collider (SLC). Such tuning is necessary to maximize the luminosity, by minimizing the beam size at the interaction point, and to reduce backgrounds in the experiment. In the final Focus Section, the correction strategy must result from the principles of the optical design, which is based on cancellations between second order aberrations, and on the ability to measure micron-size beams typical of the SLC. In the Arcs, the corrections were designed after the initial commissioning, to make the system more error-tolerant, through a modification in the optical design, and to enable adjustments of the beam phase-space a the injection to the Final Focus System, through a harmonic perturbation technique inspired from circular accelerators. Although the overall optimization of the SLC is not entirely finished, an almost optimal set-up has been achieved for the optics of the Arcs and of the Final Focus Section. Beams with transverse sizes close to the nominal ones, of a few microns, have been obtained at the interaction point. We present and discuss our results and the optical limits to the present performance. 24 refs., 25 figs., 2 tabs.

  10. Final Report for the UNIVERSITY-BASED DETECTOR RESEARCH AND DEVELOPMENT FOR THE INTERNATIONAL LINEAR COLLIDER

    SciTech Connect

    Brau, James E

    2013-04-22

    The U.S Linear Collider Detector R&D program, supported by the DOE and NSF umbrella grants to the University of Oregon, made significant advances on many critical aspects of the ILC detector program. Progress advanced on vertex detector sensor development, silicon and TPC tracking, calorimetry on candidate technologies, and muon detection, as well as on beamline measurements of luminosity, energy, and polarization.

  11. SiD Linear Collider Detector R&D, DOE Final Report

    SciTech Connect

    Brau, James E.; Demarteau, Marcel

    2015-05-15

    The Department of Energy’s Office of High Energy Physics supported the SiD university detector R&D projects in FY10, FY11, and FY12 with no-cost extensions through February, 2015. The R&D projects were designed to advance the SiD capabilities to address the fundamental questions of particle physics at the International Linear Collider (ILC): • What is the mechanism responsible for electroweak symmetry breaking and the generation of mass? • How do the forces unify? • Does the structure of space-time at small distances show evidence for extra dimensions? • What are the connections between the fundamental particles and forces and cosmology? Silicon detectors are used extensively in SiD and are well-matched to the challenges presented by ILC physics and the ILC machine environment. They are fast, robust against machine-induced background, and capable of very fine segmentation. SiD is based on silicon tracking and silicon-tungsten sampling calorimetry, complemented by powerful pixel vertex detection, and outer hadronic calorimetry and muon detection. Radiation hard forward detectors which can be read out pulse by pulse are required. Advanced calorimetry based on a particle flow algorithm (PFA) provides excellent jet energy resolution. The 5 Tesla solenoid is outside the calorimeter to improve energy resolution. PFA calorimetry requires fine granularity for both electromagnetic and hadronic calorimeters, leading naturally to finely segmented silicon-tungsten electromagnetic calorimetry. Since silicon-tungsten calorimetry is expensive, the detector architecture is compact. Precise tracking is achieved with the large magnetic field and high precision silicon microstrips. An ancillary benefit of the large magnetic field is better control of the e⁺e⁻ pair backgrounds, permitting a smaller radius beampipe and improved impact parameter resolution. Finally, SiD is designed with a cost constraint in mind. Significant advances and new capabilities have been made and

  12. 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)

  13. 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)

  14. Positron sources for Linear Colliders

    SciTech Connect

    Gai Wei; Liu Wanming

    2009-09-02

    Positron beams have many applications and there are many different concepts for positron sources. In this paper, only positron source techniques for linear colliders are covered. In order to achieve high luminosity, a linear collider positron source should have a high beam current, high beam energy, small emittance and, for some applications, a high degree of beam polarization. There are several different schemes presently being developed around the globe. Both the differences between these schemes and their common technical challenges are discussed.

  15. The status of the Stanford Linear Collider

    SciTech Connect

    Stiening, R.

    1987-03-01

    The Stanford Linear Collider is described, and the status of commissioning of the major SLC systems is given, including the electron source and 1.2 GeV linac, storage rings, 50 GeV linac, and positron source. Beam transport between the linac and final focus, and the final focus optical system are described. (LEW)

  16. International workshop on final focus and interaction regions of next generation linear colliders: Proceedings

    SciTech Connect

    Not Available

    1992-01-01

    The first day of the workshop was devoted to four plenary issues'' talks, one for each working group: Beam-Beam Interaction, Detector, Hardware, and Optical Design. The last day was devoted to plenary talks summarizing the activities of the working groups. Each of the three remaining days there,was a short morning plenary devoted to a brief summary of the preceding day and an announcement of planned working group discussions for that day. The transparencies for the issues'' and summary'' talks are included in this volume, along with some remarks from the working group chairpersons. Very briefly, the beam-beam group continued to address the quantitative study of QED induced backgrounds, and attempted to better understand the nature and prevalence of QCD millijets. The detector group attempted to identify the impact on masking and detector design of the beam-beam backgrounds, the synchrotron radiation induced backgrounds from beam halos and muon backgrounds produced primarily in collimators. Nanosecond timing elements needed in conjunction with multi-bunch operation were discussed. The hardware group addressed the problem of magnet design and support, especially the final doublet magnets suspended within the detector environment, and instrumentation issues, such as high resolution beam position monitors. The optics group discussed new final focus system ideas, collimator design, and improvement of beamline tolerances. If you were not here to participate, we hope that this volume will help you in your orientation to these problems.

  17. International workshop on final focus and interaction regions of next generation linear colliders: Proceedings

    SciTech Connect

    Not Available

    1992-11-01

    The first day of the workshop was devoted to four plenary ``issues`` talks, one for each working group: Beam-Beam Interaction, Detector, Hardware, and Optical Design. The last day was devoted to plenary talks summarizing the activities of the working groups. Each of the three remaining days there,was a short morning plenary devoted to a brief summary of the preceding day and an announcement of planned working group discussions for that day. The transparencies for the ``issues`` and ``summary`` talks are included in this volume, along with some remarks from the working group chairpersons. Very briefly, the beam-beam group continued to address the quantitative study of QED induced backgrounds, and attempted to better understand the nature and prevalence of QCD millijets. The detector group attempted to identify the impact on masking and detector design of the beam-beam backgrounds, the synchrotron radiation induced backgrounds from beam halos and muon backgrounds produced primarily in collimators. Nanosecond timing elements needed in conjunction with multi-bunch operation were discussed. The hardware group addressed the problem of magnet design and support, especially the final doublet magnets suspended within the detector environment, and instrumentation issues, such as high resolution beam position monitors. The optics group discussed new final focus system ideas, collimator design, and improvement of beamline tolerances. If you were not here to participate, we hope that this volume will help you in your orientation to these problems.

  18. 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.

  19. 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.

  20. 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.

  1. International Workshop on Linear Colliders 2010

    SciTech Connect

    2010-10-25

    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

  2. SUSY Without Prejudice at Linear Colliders

    SciTech Connect

    Rizzo, Thomas G.

    2008-12-11

    We explore the physics of the general CP-conserving MSSM with Minimal Flavor Violation, the pMSSM. The 19 soft SUSY breaking parameters are chosen so to satisfy all existing experimental and theoretical constraints assuming that the WIMP is the lightest neutralino. We scan this parameter space twice using both flat and log priors and compare the results which yield similar conclusions. Constraints from both LEP and the Tevatron play an important role in obtaining our final model samples. Implications for future TeV-scale e{sup +}e{sup -} linear colliders (LC) are discussed.

  3. International Workshop on Linear Colliders 2010

    ScienceCinema

    None

    2016-07-12

    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

  4. 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.

  5. 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.

  6. 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

  7. Linear collider research and development at SLAC, LBL and LLNL

    SciTech Connect

    Mattison, T.S.

    1988-10-01

    The study of electron-positron (e/sup +/e/sup /minus//) annihilation in storage ring colliders has been very fruitful. It is by now well understood that the optimized cost and size of e/sup +/e/sup /minus// storage rings scales as E(sub cm//sup 2/ due to the need to replace energy lost to synchrotron radiation in the ring bending magnets. Linear colliders, using the beams from linear accelerators, evade this scaling law. The study of e/sup +/e/sup /minus// collisions at TeV energy will require linear colliders. The luminosity requirements for a TeV linear collider are set by the physics. Advanced accelerator research and development at SLAC is focused toward a TeV Linear Collider (TLC) of 0.5--1 TeV in the center of mass, with a luminosity of 10/sup 33/--10/sup 34/. The goal is a design for two linacs of less than 3 km each, and requiring less than 100 MW of power each. With a 1 km final focus, the TLC could be fit on Stanford University land (although not entirely within the present SLAC site). The emphasis is on technologies feasible for a proposal to be framed in 1992. Linear collider development work is progressing on three fronts: delivering electrical energy to a beam, delivering a focused high quality beam, and system optimization. Sources of high peak microwave radio frequency (RF) power to drive the high gradient linacs are being developed in collaboration with Lawrence Berkeley Laboratory (LBL) and Lawrence Livermore National Laboratory (LLNL). Beam generation, beam dynamics and final focus work has been done at SLAC and in collaboration with KEK. Both the accelerator physics and the utilization of TeV linear colliders were topics at the 1988 Snowmass Summer Study. 14 refs., 4 figs., 1 tab.

  8. 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.

  9. 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.

  10. 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.

  11. 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.

  12. 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

  13. BEAM-BASED NON-LINEAR OPTICS CORRECTIONS IN COLLIDERS.

    SciTech Connect

    PILAT, R.; LUO, Y.; MALITSKY, N.; PTITSYN, V.

    2005-05-16

    A method has been developed to measure and correct operationally the non-linear effects of the final focusing magnets in colliders, that gives access to the effects of multi-pole errors by applying closed orbit bumps, and analyzing the resulting tune and orbit shifts. This technique has been tested and used during 4 years of RHIC (the Relativistic Heavy Ion Collider at BNL) operations. I will discuss here the theoretical basis of the method, the experimental set-up, the correction results, the present understanding of the machine model, the potential and limitations of the method itself as compared with other non-linear correction techniques.

  14. 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.

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

    ScienceCinema

    None

    2016-07-12

    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.

  16. 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

  17. Slepton Flavor Physics at Linear Colliders

    NASA Astrophysics Data System (ADS)

    Dine, Michael; Grossman, Yuval; Thomas, Scott

    If low energy supersymmetry is realized in nature it is possible that a first generation linear collider will only have access to some of the superpartners with electroweak quantum numbers. Among these, sleptons can provide sensitive probes for lepton flavor violation through potentially dramatic lepton violating signals. Theoretical proposals to understand the absence of low energy quark and lepton flavor changing neutral currents are surveyed and many are found to predict observable slepton flavor violating signals at linear colliders. The observation or absence of such sflavor violation will thus provide important indirect clues to very high energy physics. Previous analyses of slepton flavor oscillations are also extended to include the effects of finite width and mass differences.

  18. 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)

  19. 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.

  20. 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.

  1. 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.

  2. 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.

  3. 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.

  4. Performance of the SLAC Linear Collider klystrons

    SciTech Connect

    Allen, M.A.; Fowkes, W.R.; Koontz, R.F.; Schwarz, H.D.; Seeman, J.T.; Vlieks, A.E.

    1987-01-01

    There are now 200 new, high power 5045 klystrons installed on the two-mile Stanford Linear Accelerator. Peak power per klystron averages over 63 MW. Average energy contribution is above 240 MeV per station. Electron beam energy has been measured as high as 53 GeV. Energy instability due to klystron malfunction is less than 0.2%. The installed klystrons have logged over one million operating hours with close to 20,000 klystron hours cumulative operating time between failures. Data are being accumulated on klystron operation and failure modes with failure signatures starting to become apparent. To date, no wholesale failure modes have surfaced that would impair the SLAC Linear Collider (SLC) program.

  5. Sfermion precision measurements at a linear collider

    SciTech Connect

    A. Freitas et al.

    2003-09-25

    At future e{sup +}e{sup -} linear colliders, the event rates and clean signals of scalar fermion production--in particular for the scalar leptons--allow very precise measurements of their masses and couplings and the determination of their quantum numbers. Various methods are proposed for extracting these parameters from the data at the sfermion thresholds and in the continuum. At the same time, NLO radiative corrections and non-zero width effects have been calculated in order to match the experimental accuracy. The substantial mixing expected for the third generation sfermions opens up additional opportunities. Techniques are presented for determining potential CP-violating phases and for extracting tan {beta} from the stau sector, in particular at high values. The consequences of possible large mass differences in the stop and sbottom system are explored in dedicated analyses.

  6. High pulse power rf sources for linear colliders

    SciTech Connect

    Wilson, P.B.

    1983-09-01

    RF sources with high peak power output and relatively short pulse lengths will be required for future high gradient e/sup +/e/sup -/ linear colliders. The required peak power and pulse length depend on the operating frequency, energy gradient and geometry of the collider linac structure. The frequency and gradient are in turn constrained by various parameters which depend on the beam-beam collision dynamics, and on the total ac wall-plug power that has been committed to the linac rf system. Various rf sources which might meet these requirements are reviewed. Existing source types (e.g., klystrons, gyrotrons) and sources which show future promise based on experimental prototypes are first considered. Finally, several proposals for high peak power rf sources based on unconventional concepts are discussed. These are an FEL source (two beam accelerator), rf energy storage cavities with switching, and a photocathode device which produces an rf current by direct emission modulation of the cathode.

  7. Linear collider approach to a B anti B factory

    SciTech Connect

    Wilson, P.B.

    1987-06-01

    In this paper we consider the basic design expression and principal design constraints for a linear collider suitable for a B anti-B factory: Energy approx. =10 GeV, luminosity 10/sup 33/-10/sup 34/ cm/sup -2/s/sup -1/, energy resolution approx. =10/sup -2/. The design of room temperature linear colliders for a B factory is discussed. In such colliders, the rf energy stored in the linac structure is thrown away after each linac pulse. Linear colliders using superconducting rf cavities are considered. Some brief conclusions are presented.

  8. Luminosity Limitations of Linear Colliders Based on Plasma Acceleration

    SciTech Connect

    Lebedev, Valeri; Burov, Alexey; Nagaitsev, Sergei

    2016-01-01

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

  9. Comparison of two approaches to linear collider design

    SciTech Connect

    Schnell, W.

    1987-11-01

    This paper reviews linear collider parameters. It aims at analyzing two specific design approachs - the ones for CLIC at CERN and for a TeV linear collider at SLAC - which appear to lead into remarkably different directions although they start from the same premises and try to respect the same boundary conditions. 19 refs.

  10. 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.

  11. Calculation of detector backgrounds at TeV linear colliders

    SciTech Connect

    Himel, T.

    1988-11-01

    It is necessary to carefully design masks and beam lines to prevent the high energy physics detector from being inundated with background particles from a high energy linear collider. Presented here are preliminary calculations on two of the three expected backgrounds: photons from synchrotron radiation produced in the final focus quadrupoles, and electrons which lose energy due to bremsstrahlung and are then bent into a mask or quadrupole by the field of the opposite beam. The former can be controlled with proper masking. The latter may pose a problem, so further calculations are needed. Work was also done on the third expected source of background: electrons in the tail of the beam which hit masks where showers are made whose products enter the detector. This work was very preliminary and is not included in this write-up. All the calculations here are based on the 1 TeV center-of-mass linear collider design of R. Palmer and the final focus design of K. Oide which can be found in these proceedings. Extrapolations to other accelerator designs should be straightforward.

  12. Unique radiation problems associated with the SLAC Linear Collider

    SciTech Connect

    Jenkins, T.M.; Nelson, W.R.

    1987-01-01

    The SLAC Linear Collider (SLC) is a variation of a new class of linear colliders whereby two linear accelerators are aimed at each other to collide intense bunches of electrons and positrons together. Conventional storage rings are becoming ever more costly as the energy of the stored beams increases such that the cost of two linear colliders per GeV is less than that of electron-positron storage rings at cm energies above about 100 GeV. The SLC being built at SLAC is designed to achieve a center-of-mass energy of 100 GeV by accelerating intense bunches of particles, both electrons and positrons, in the SLAC linac and transporting them along two different arcs to a point where they are focused to a small radius and made to collide head on. The SLC has two main goals. The first is to develop the physics and technology of linear colliders. The other is to achieve center-of-mass energies above 90 GeV in order to investigate the unification of the weak and electromagnetic interactions in the energy range above 90 GeV; (i.e., Z/sup 0/, etc.). This note discusses a few of the special problems that were encountered by the Radiation Physics group at SLAC during the design and construction of the SLAC Linear Collider. The nature of these problems is discussed along with the methods employed to solve them.

  13. 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.

  14. 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.

  15. Report on the international workshop on next generation linear colliders

    SciTech Connect

    Ruth, R.D.

    1989-05-01

    Many laboratories around the world have begun vigorous research programs on a next generation linear collider (NLC). However, it has been recognized that the research towards NLC is beyond the capabilities of any one laboratory presently. This workshop was organized to begin a series of workshops that address this problem. Specifically, the main goals of the workshop were to discuss research programs of the various laboratories around the world, to identify common areas of interest in the various NLC designs, and finally to advance these programs by collaboration. The particular topics discussed briefly in this paper are: parameters, rf power, structures, final focus, beam dynamics, damping rings, and instrumentation. 2 refs., 3 figs., 6 tabs.

  16. Isolating Non-Linear Signatures of Two Colliding Black Holes

    NASA Astrophysics Data System (ADS)

    Garrido, Rita

    2012-03-01

    The early and late stages of the binary-black-hole collision can be approximated by perturbations to a background, solutions to linearization of the Einstein's equations. However, once the two black holes are within several radii of each other, and ultimately collide, the solution is intrinsically non-linear. The main objective is to intuitively understand the non-linear portion of the solution to the Einstein equation by performing simulations of such mergers. I will identify the non-linear regime through a process of elimination. The early stages of the coalescence are well known by post-Newtonian theory. The end state is approximated very well by perturbation theory, the waveforms decay as a damped sinusoidal with a frequency and decay time uniquely determined by the mass and spin of the final black hole in theory. I will isolate the non-linear portion of the waveform by fitting the early stages to the post-Newtonian solution and the late stages to the perturbative solution. What remains is the non-linear region. Once isolated, we will search through the physics parameter space of the binary black holes for bulk features. These features can then be used to fine-tune the search algorithms hunting for these collisions with LIGO.

  17. 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.

  18. Free Electron Laser for Gamma-Gamma Collider at a Low-Energy Option of International Linear Collider

    SciTech Connect

    Saldin, Evgeny; Schneidmiller, Evgeny; Yurkov, Mikhail; Seryi, Andrei; /SLAC

    2009-10-30

    Different scenarios of a start-up with International Linear Collider (ILC) are under discussion at the moment in the framework of the Global Design Effort (GDE). One of them assumes construction of the ILC in stages from some minimum CM energy up to final target of 500 GeV CM energy. Gamma-gamma collider with CM energy of 180GeV is considered as a candidate for the first stage of the facility. In this report we present conceptual design of a free electron laser as a source of primary photons for the first stage of ILC.

  19. A bunch compressor for the Next Linear Collider

    SciTech Connect

    Emma, P.; Raubenheimer, T.; Zimmermann, F.

    1995-06-01

    A bunch compressor design for the Next Linear Collider (NLC) is described. The compressor reduces the bunch length by a factor of 40 in two stages. The first stage at 2 GeV consists of an rf section and a wiggler. The second stage at 10 GeV is formed by an arc, an rf section, and a chicane. The final bunch phase is insensitive to initial phase errors and to beam loading in the intermediate S-band pre-linac. Residual longitudinal aberrations of the system are partially compensated. The bunch compressor encompasses a solenoid spin-rotator system at 2 GeV that allows complete control over the spin orientation.

  20. Alternate approaches to future electron-positron linear colliders

    SciTech Connect

    Loew, G.A.

    1998-07-01

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

  1. Final focus designs for crab waist colliders

    NASA Astrophysics Data System (ADS)

    Bogomyagkov, A.; Levichev, E.; Piminov, P.

    2016-12-01

    The crab waist collision scheme promises significant luminosity gain. The successful upgrade of the DA Φ NE collider proved the principle of crab waist collision and increased luminosity 3 times. Therefore, several new projects try to implement the scheme. The paper reviews interaction region designs with the crab waist collision scheme for already existent collider DA Φ NE and SuperKEKB, presently undergoing commissioning, for the projects of SuperB in Italy, CTau in Novosibirsk and FCC-ee at CERN.

  2. Proceedings of the 2005 International Linear Collider Workshop (LCWS05)

    SciTech Connect

    Hewett, JoAnne,; /SLAC

    2006-12-18

    Exploration of physics at the TeV scale holds the promise of addressing some of our most basic questions about the nature of matter, space, time, and energy. Discoveries of the Electroweak Symmetry Breaking mechanism, Supersymmetry, Extra Dimensions of space, Dark Matter particles, and new forces of nature are all possible. We have been waiting and planning for this exploration for over 20 years. In 2007 the Large Hadron Collider at CERN will begin its operation and will break into this new energy frontier. A new era of understanding will emerge as the LHC data maps out the Terascale. With the LHC discoveries, new compelling questions will arise. Responding to these questions will call for a new tool with greater sensitivity--the International Linear Collider. Historically, the most striking progress in the exploration of new energy frontiers has been made from combining results from hadron and electron-positron colliders. The precision measurements possible at the ILC will reveal the underlying theory which gave rise to the particles discovered at the LHC and will open the window to even higher energies. The world High Energy Physics community has reached an accord that an e+e- linear collider operating at 0.5-1.0 TeV would provide both unique and essential scientific opportunities; the community has endorsed with highest priority the construction of such a machine. A major milestone toward this goal was reached in August 2004 when the International Committee on Future Accelerators approved a recommendation for the technology of the future International Linear Collider. A global research and design effort is now underway to construct a global design report for the ILC. This endeavor is directed by Barry Barrish of the California Institute of Technology. The offer, made by Jonathan Dorfan on the behalf of ICFA, and acceptance of this directorship took place during the opening plenary session of this workshop. The 2005 International Linear Collider Workshop was held

  3. Power Saving Optimization for Linear Collider Interaction Region Parameters

    SciTech Connect

    Seryi, Andrei; /SLAC

    2009-10-30

    Optimization of Interaction Region parameters of a TeV energy scale linear collider has to take into account constraints defined by phenomena such as beam-beam focusing forces, beamstrahlung radiation, and hour-glass effect. With those constraints, achieving a desired luminosity of about 2E34 would require use of e{sup +}e{sup -} beams with about 10 MW average power. Application of the 'travelling focus' regime may allow the required beam power to be reduced by at least a factor of two, helping reduce the cost of the collider, while keeping the beamstrahlung energy loss reasonably low. The technique is illustrated for the 500 GeV CM parameters of the International Linear Collider. This technique may also in principle allow recycling the e{sup +}e{sup -} beams and/or recuperation of their energy.

  4. Lepton flavor violating processes at the International Linear Collider

    SciTech Connect

    Ferreira, P. M.; Guedes, R. B.; Santos, R.

    2007-03-01

    We study the effects of dimension-six effective operators on the flavor violating production and decay of leptons at the International Linear Collider. Analytic expressions for the cross sections, decay widths, and asymmetries of all flavor changing processes will be presented, as well as an analysis of the feasibility of their observation at the ILC.

  5. SLAC linear collider: the machine, the physics, and the future

    SciTech Connect

    Richter, B.

    1981-11-01

    The SLAC linear collider, in which beams of electrons and positrons are accelerated simultaneously, is described. Specifications of the proposed system are given, with calculated preditions of performance. New areas of research made possible by energies in the TeV range are discussed. (GHT)

  6. Production of high intensity electron bunches for the SLAC Linear Collider

    SciTech Connect

    James, M.B.

    1987-08-01

    This thesis describes the design and performance of a high intensity electron injecfor for the SLAC Linear Collider. Motivation for the collider and the specifications for the injector are discussed. An analytic theory of the bunching and capture of electrons by rf fields is discussed in the limit of low space charge and small signal. The design and performance of SLAC's main injector are described to illustrate a successful application of this theory. The bunching and capture of electrons by rf fields are then discussed in the limit of high space charge and large signal, and a description of the design of the collider injector follows. In the limit of high space charge forces and large rf signals, the beam dynamics are considerably more complex and numerical simulations are required to predict particle motion. A computer code which models the longitudinal dynamics of electrons in the presence of space charge and rf fields is described. The results of the simulations, the resulting collider injector design and the various components which make up the collider injector are described. These include the gun, subharmonic bunchers, traveling-wave buncher and velocity-of-light accelerator section. Finally, the performance of the injector is described including the beam intensity, bunch length, transverse emittance and energy spectrum. While the final operating conditions differ somewaht from the design, the performance of the collider injector is in good agreement with the numerical simulations and meets all of the collider specifications. 28 refs.

  7. Proceedings of the international workshop on next-generation linear colliders

    SciTech Connect

    Riordan, M.

    1988-12-01

    This report contains papers on the next-generation of linear colliders. The particular areas of discussion are: parameters; beam dynamics and wakefields; damping rings and sources; rf power sources; accelerator structures; instrumentation; final focus; and review of beam-beam interaction.

  8. Development of a Non-Magnetic Inertial Sensor for Vibration Stabilization in a Linear Collider

    SciTech Connect

    Frisch, Josef; Decker, Valentin; Doyle, Eric; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Seryi, Andrei; Chang, Allison; Partridge, Richard; /Brown U.

    2006-09-01

    One of the options for controlling vibration of the final focus magnets in a linear collider is to use active feedback based on accelerometers. While commercial geophysics sensors have noise performance that substantially exceeds the requirements for a linear collider, they are physically large, and cannot operate in the strong magnetic field of the detector. Conventional nonmagnetic sensors have excessive noise for this application. We report on the development of a non-magnetic inertial sensor, and on a novel commercial sensor both of which have demonstrated the required noise levels for this application.

  9. Physics considerations for laser-plasma linear colliders

    SciTech Connect

    Schroeder, Carl; Esarey, Eric; Geddes, Cameron; Benedetti, Carlo; Leemans, Wim

    2010-06-11

    Physics considerations for a next-generation linear collider based on laser-plasma accelerators are discussed. The ultra-high accelerating gradient of a laser-plasma accelerator and short laser coupling distance between accelerator stages allows for a compact linac. Two regimes of laser-plasma acceleration are discussed. The highly nonlinear regime has the advantages of higher accelerating fields and uniform focusing forces, whereas the quasi-linear regime has the advantage of symmetric accelerating properties for electrons and positrons. Scaling of various accelerator and collider parameters with respect to plasma density and laser wavelength are derived. Reduction of beamstrahlung effects implies the use of ultra-short bunches of moderate charge. The total linac length scales inversely with the square root of the plasma density, whereas the total power scales proportional to the square root of the density. A 1 TeV center-of-mass collider based on stages using a plasma density of 10{sup 17} cm{sup -3} requires tens of J of laser energy per stage (using 1 {micro}m wavelength lasers) with tens of kHz repetition rate. Coulomb scattering and synchrotron radiation are examined and found not to significantly degrade beam quality. A photon collider based on laser-plasma accelerated beams is also considered. The requirements for the scattering laser energy are comparable to those of a single laser-plasma accelerator stage.

  10. Polarized positrons and electrons at the linear collider

    NASA Astrophysics Data System (ADS)

    Moortgat-Pick, G.; Abe, T.; Alexander, G.; Ananthanarayan, B.; Babich, A. A.; Bharadwaj, V.; Barber, D.; Bartl, A.; Brachmann, A.; Chen, S.; Clarke, J.; Clendenin, J. E.; Dainton, J.; Desch, K.; Diehl, M.; Dobos, B.; Dorland, T.; Dreiner, H. K.; Eberl, H.; Ellis, J.; Flöttmann, K.; Fraas, H.; Franco-Sollova, F.; Franke, F.; Freitas, A.; Goodson, J.; Gray, J.; Han, A.; Heinemeyer, S.; Hesselbach, S.; Hirose, T.; Hohenwarter-Sodek, K.; Juste, A.; Kalinowski, J.; Kernreiter, T.; Kittel, O.; Kraml, S.; Langenfeld, U.; Majerotto, W.; Martinez, A.; Martyn, H.-U.; Mikhailichenko, A.; Milstene, C.; Menges, W.; Meyners, N.; Mönig, K.; Moffeit, K.; Moretti, S.; Nachtmann, O.; Nagel, F.; Nakanishi, T.; Nauenberg, U.; Nowak, H.; Omori, T.; Osland, P.; Pankov, A. A.; Paver, N.; Pitthan, R.; Pöschl, R.; Porod, W.; Proulx, J.; Richardson, P.; Riemann, S.; Rindani, S. D.; Rizzo, T. G.; Schälicke, A.; Schüler, P.; Schwanenberger, C.; Scott, D.; Sheppard, J.; Singh, R. K.; Sopczak, A.; Spiesberger, H.; Stahl, A.; Steiner, H.; Wagner, A.; Weber, A. M.; Weiglein, G.; Wilson, G. W.; Woods, M.; Zerwas, P.; Zhang, J.; Zomer, F.

    2008-05-01

    The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.

  11. Photoinjectors R&D for future light sources & linear colliders

    SciTech Connect

    Piot, P.; /Northern Illinois U. /Fermilab

    2006-08-01

    Linac-driven light sources and proposed linear colliders require high brightness electron beams. In addition to the small emittances and high peak currents, linear colliders also require spin-polarization and possibly the generation of asymmetric beam in the two transverse degrees of freedom. Other applications (e.g., high-average-power free-electron lasers) call for high duty cycle and/or (e.g., electron cooling) angular-momentum-dominated electron beams. We review ongoing R&D programs aiming at the production of electron beams satisfying these various requirements. We especially discuss R&D on photoemission electron sources (with focus on radiofrequency guns) along with the possible use of emittance-manipulation techniques.

  12. Plasma Lens Backgrounds at a Future Linear Collider

    SciTech Connect

    Weidemann, Achim W

    2002-04-29

    A ''plasma lens'' might be used to enhance the luminosity of future linear colliders. However, its utility for this purpose depends largely on the potential backgrounds that may be induced by the insertion of such a device in the interaction region of the detector.In this note we identify different sources of such backgrounds, calculate their event rates from the elementary interaction processes, and evaluate their effects on the major parts of a hypothetical Next Linear Collider (NLC) detector. For plasma lens parameters which give a factor of seven enhancement of the luminosity, and using the NLC design for beam parameters as a reference, we find that the background yields are fairly high, and require further study and improvements in detector technology to avoid their impact.

  13. 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.

  14. New timing system for the Stanford Linear Collider

    SciTech Connect

    Paffrath, L.; Bernstein, D.; Kang, H.; Koontz, R.; Leger, G.; Ross, M.; Pierce, W.; Wilmunder, A.

    1984-11-01

    In order to be able to meet the goals of the Stanford Linear Collider, a much more precise timing system had to be implemented. This paper describes the specification and design of this system, and the results obtained from its use on 1/3 of the SLAC linac. The functions of various elements are described, and a programmable delay unit (PDU) is described in detail.

  15. Emittance calculations for the Stanford Linear Collider injector

    SciTech Connect

    Sheppard, J.C.; Clendenin, J.E.; Helm, R.H.; Lee, M.J.; Miller, R.H.; Blocker, C.A.

    1983-03-01

    A series of measurements have been performed to determine the emittance of the high intensity, single bunch beam that is to be injected into the Stanford Linear Collider. On-line computer programs were used to control the Linac for the purpose of data acquisition and to fit the data to a model in order to deduce the beam emittance. This paper will describe the method of emittance calculation and present some of the measurement results.

  16. Final Muon Emittance Exchange in Vacuum for a Collider

    SciTech Connect

    Summers, Don; Acosta, John; Cremaldi, Lucien; Hart, Terry; Oliveros, Sandra; Perera, Lalith; Wu, Wanwei; Neuffer, David

    2015-05-07

    We outline a plan for final muon ionization cooling with quadrupole doublets focusing onto short absorbers followed by emittance exchange in vacuum to achieve the small transverse beam sizes needed by a muon collider. A flat muon beam with a series of quadrupole doublet half cells appears to provide the strong focusing required for final cooling. Each quadrupole doublet has a low β region occupied by a dense, low Z absorber. After final cooling, normalized xyz emittances of (0.071, 0.141, 2.4) mm-rad are exchanged into (0.025, 0.025, 70) mm-rad. Thin electrostatic septa efficiently slice the bunch into 17 parts. The 17 bunches are interleaved into a 3.7 meter long train with RF deflector cavities. Snap bunch coalescence combines the muon bunch train longitudinally in a 21 GeV ring in 55 μs, one quarter of a synchrotron oscillation period. A linear long wavelength RF bucket gives each bunch a different energy causing the bunches to drift until they merge into one bunch and can be captured in a short wavelength RF bucket with a 13% muon decay loss and a packing fraction as high as 87%.

  17. Linear Collider Physics Resource Book for Snowmass 2001

    SciTech Connect

    Peskin, Michael E

    2001-06-05

    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.

  18. 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.

  19. Acclerator R&D for a Linear Collider

    SciTech Connect

    Rubin, D.L.; Dugan, G.; Gibbons, L.; Palmer, M.; Patterson, R.; Sagan, D.; Smith, J.C.; Tenenbaum, P.; Woodley, M.; Fields, J.; Urban, J.

    2008-11-26

    The goal of this project was to perform simulations of beam transport in linear colliders, with an emphasis on emittance dilution, spin polarization transport, and development and testing of beam based tuning algorithms. Our simulations are based on an existing object-oriented particle-tracking library, Bmad. To facilitate the efficient development of simulations, an accelerator design and analysis program based on Bmad has been developed called Tao (Tool for Accelerator Optics). The three beam-based alignment algorithms, Dispersion Free Steering, Ballistic Alignment (BA), and the Kubo Method have been implemented in Tao. We have studied the effects of magnet misalignments, BPM resolution, beam jitter, stray fields, BPM and steering magnet failure and the effects of various cavity shape wakefields. A parametric study has been conducted in the presence of the above types of errors for all three alignment algorithms. We find that BPM resolution has only modest impact on the effectiveness of beam based alignment. The DFS correction algorithm was found to be very robust in situations where there were BPM and/or steering magnet failures. The wakefields in the main linac are very weak and cause negligible emittance growth. Spin tracking was extended to study all accelerator components between the damping ring and the interaction point, including RF cavities and the helical undulator. We find that there is no significant depolarization in the RTML, main linac or beam delivery system and that the polarization is relatively insensitive to misalignment. We have developed an effective spin rotator. During the final year of the grant we exploited the computing power of our new linux cluster, along with the modeling codes that we had developed, to investigate damping ring physics and design, specifically as it relates to the CESR Test Accelerator project.

  20. International Linear Collider Technical Review Committee: Second Report, 2003

    SciTech Connect

    Loew, Gregory

    2003-02-21

    As this report is being published, the international high energy physics (HEP) community finds itself confronting a set of fascinating discoveries and new questions regarding the nature of matter and its fundamental particles and forces. The observation of neutrino oscillations that indicates that neutrinos have mass, measurements of the accelerating expansion of the universe that may be due to dark energy, and evidence for a period of rapid inflation at the beginning of the Big Bang are stimulating the entire field. Looming on the horizon are the potential discoveries of a Higgs particle that may reveal the origin of mass and of a whole family of supersymmetric particles that may be part of the cosmic dark matter. For the HEP community to elucidate these mysteries, new accelerators are indispensable. At this time, after careful deliberations, all three regional organizations of the HEP community (ACFA in Asia, HEPAP in North America, and ECFA in Europe) have reached the common conclusion that the next accelerator should be an electron-positron linear collider with an initial center-of-mass energy of 500 Giga-electronvolts (GeV), later upgradable to higher energies, and that it should be built and operated in parallel with the Large Hadron Collider under construction at CERN. Hence, this second report of the International Linear Collider Technical Review Committee (ILC-TRC) comes at a very timely moment. The report was requested by the International Committee on Future Accelerators (ICFA) in February 2001 to assess the current technical status of electron-positron linear collider designs in the various regions. Note that the ILC-TRC was not asked to concern itself with either cost studies or the ultimate selection process of a machine. This Executive Summary gives a short outline of the genesis of the report, the charge given to the committee, and its organization. It then presents a brief description of four electron-positron linear collider designs at hand. The

  1. 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.

  2. RF properties of periodic accelerating structures for linear colliders

    SciTech Connect

    Wang, J.W.

    1989-07-01

    With the advent of the SLAC electron-positron linear collider (SLC) in the 100 GeV center-of-mass energy range, research and development work on even higher energy machines of this type has started in several laboratories in the United States, Europe, the Soviet Union and Japan. These linear colliders appear to provide the only promising approach to studying e/sup /plus//e/sup /minus// physics at center-of-mass energies approaching 1 TeV. This thesis concerns itself with the study of radio frequency properties of periodic accelerating structures for linear colliders and their interaction with bunched beams. The topics that have been investigated are: experimental measurements of the energy loss of single bunches to longitudinal modes in two types of structures, using an equivalent signal on a coaxial wire to simulate the beam; a method of canceling the energy spread created within a single bunch by longitudinal wakefields, through appropriate shaping of the longitudinal charge distribution of the bunch; derivation of the complete transient beam-loading equation for a train of bunches passing through a constant-gradient accelerator section, with application to the calculation and minimization of multi-bunch energy spread; detailed study of field emission and radio frequency breakdown in disk-loaded structures at S-, C- and X-band frequencies under extremely high-gradient conditions, with special attention to thermal effects, radiation, sparking, emission of gases, surface damage through explosive emission and its possible control through RF-gas processing. 53 refs., 49 figs., 9 tabs.

  3. 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.

  4. Linear accelerators for TeV colliders. Revision

    SciTech Connect

    Wilson, P.B.

    1985-10-01

    The basic scaling relations for important linear collider design parameters are introduced. Some of the basic concepts concerning the design of accelerating structures are presented, and breakdown limitations are discussed. Rf power sources are considered. Some of the key concepts of wakefield accelerators are discussed, and some examples of wake fields for typical linac structures are presented. Some general concepts concerning emittance, and the limitations on the emittance that can be obtained from linac guns and damping rings are discussed. 49 refs., 15 figs. (LEW)

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

    PubMed

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

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

  6. Physics at the e⁺e⁻ linear collider

    SciTech Connect

    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.

  7. Staging optics considerations for a plasma wakefield acceleration linear collider

    NASA Astrophysics Data System (ADS)

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

    2016-09-01

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

  8. The Optimized Bunch Compressor for the International Linear Collider

    SciTech Connect

    Seletskiy, S.; Tenenbaum, P.; /SLAC

    2007-07-06

    The International Linear Collider (ILC) utilizes a two stage Bunch Compressor (BC) that compresses the RMS bunch length from 9 mm to 200 to 300 micrometers before sending the electron beam to the Main Linac. This paper reports on the new design of the optimized BC wiggler. It was reduced in length by more than 30%. The introduction of nonzero dispersion slope in the BC wigglers enabled them to generate the required compression while having a small SR emittance growth, a tunability range of over a factor of 2 in each wiggler, and less than 3% RMS energy spread throughout the entire system.

  9. Fourth standard model family neutrino at future linear colliders

    SciTech Connect

    Ciftci, A.K.; Ciftci, R.; Sultansoy, S.

    2005-09-01

    It is known that flavor democracy favors the existence of the fourth standard model (SM) family. In order to give nonzero masses for the first three-family fermions flavor democracy has to be slightly broken. A parametrization for democracy breaking, which gives the correct values for fundamental fermion masses and, at the same time, predicts quark and lepton Cabibbo-Kobayashi-Maskawa (CKM) matrices in a good agreement with the experimental data, is proposed. The pair productions of the fourth SM family Dirac ({nu}{sub 4}) and Majorana (N{sub 1}) neutrinos at future linear colliders with {radical}(s)=500 GeV, 1 TeV, and 3 TeV are considered. The cross section for the process e{sup +}e{sup -}{yields}{nu}{sub 4}{nu}{sub 4}(N{sub 1}N{sub 1}) and the branching ratios for possible decay modes of the both neutrinos are determined. The decays of the fourth family neutrinos into muon channels ({nu}{sub 4}(N{sub 1}){yields}{mu}{sup {+-}}W{sup {+-}}) provide cleanest signature at e{sup +}e{sup -} colliders. Meanwhile, in our parametrization this channel is dominant. W bosons produced in decays of the fourth family neutrinos will be seen in detector as either di-jets or isolated leptons. As an example, we consider the production of 200 GeV mass fourth family neutrinos at {radical}(s)=500 GeV linear colliders by taking into account di-muon plus four jet events as signatures.

  10. Ingot Nb based SRF technology for the International Linear Collider

    SciTech Connect

    Yamamoto, Akira; Yamanaka, Masashi; Myneni, Ganapati

    2015-12-04

    The International Linear Collider (ILC) is anticipated to be built as the next energy-frontier electron-positron colliding accelerator with a global effort in particle physics. Niobium based Superconducting Radio-Frequency (SRF) technology is required to provide beam-accelerating structure with elliptical cavity strings to linearly accelerate the electron and positron beams up to 250 GeV and to realize a center-of-mass energy of 500 GeV in collisions. The accelerator design and R&D efforts progressed, and the ILC Technical Design Report (ILC-TDR) was published in 2013. Niobium will take a critical role to generate electric field gradient with a frequency of 1.3 GHz, for accelerating the beam with the best efficiency, in energy balance, using RF superconductivity. This paper discusses a technical approach to provide Nb material (ingot) and thin disks for producing the elliptical cavity structure, with direct slicing from Nb ingot having sufficiently optimized purity and residual resistance ration (RRR) necessary for the ILC SRF cavities.

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

    SciTech Connect

    Baer, Howard; Barklow, Tim; Fujii, Keisuke; Gao, Yuanning; Hoang, Andre; Kanemura, Shinya; List, Jenny; Logan, Heather E.; Nomerotski, Andrei; Perelstein, Maxim; Peskin, Michael E.; Pöschl, Roman; Reuter, Jürgen; Riemann, Sabine; Savoy-Navarro, Aurore; Tait, Tim P.; Yu, Jaehoon

    2013-06-26

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

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

    SciTech Connect

    Behnke, Ties

    2013-06-26

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

  13. Parallel computation of transverse wakes in linear colliders

    SciTech Connect

    Zhan, Xiaowei; Ko, Kwok

    1996-11-01

    SLAC has proposed the detuned structure (DS) as one possible design to control the emittance growth of long bunch trains due to transverse wakefields in the Next Linear Collider (NLC). The DS consists of 206 cells with tapering from cell to cell of the order of few microns to provide Gaussian detuning of the dipole modes. The decoherence of these modes leads to two orders of magnitude reduction in wakefield experienced by the trailing bunch. To model such a large heterogeneous structure realistically is impractical with finite-difference codes using structured grids. The authors have calculated the wakefield in the DS on a parallel computer with a finite-element code using an unstructured grid. The parallel implementation issues are presented along with simulation results that include contributions from higher dipole bands and wall dissipation.

  14. Fermionic effective operators and Higgs production at a linear collider

    SciTech Connect

    Kile, Jennifer; Ramsey-Musolf, Michael J.

    2007-09-01

    We study the possible contributions of dimension six operators containing fermion fields to Higgs production at a 500 GeV or 1 TeV e{sup +}e{sup -} linear collider. We show that--depending on the production mechanism--the effects of such operators can be kinematically enhanced relative to standard model (SM) contributions. We determine constraints on the operator coefficients implied by existing precision electroweak measurements and the scale of neutrino mass. We find that even in the presence of such constraints, substantial deviations from SM Higgs production cross sections are possible. We compare the effects of fermionic operators with those associated with purely bosonic operators that have been previously discussed in the literature.

  15. Note on the SC Linear Collider TESLA Cavity Design

    NASA Astrophysics Data System (ADS)

    Sekutowicz, J.; Proch, D.; Tang, C.

    1997-05-01

    The experience we have gained over the last few years from experiments with superconducting cavities for the TESLA test facility justifies a revision of the design decided almost five years ago. The proposed new design takes advantage of the high quality factor Q0 > 10^10 and the low electron emission as demonstrated by some tested cavities. The main aim of the new design is to simplify the production and preparation of sc cavities and thus to reduce the cost of the linear collider. The new cavity shape has an enlarged iris diameter with the following advantages: significant lower loss factors, simplified and less expensive scheme for the HOM damping, suitability of hydroforming and higher stability of the field profile.

  16. Beam Instrumentation Challenges at the International Linear Collider

    SciTech Connect

    Tenenbaum, Peter; /SLAC

    2006-05-16

    The International Linear Collider (ILC) is a proposed facility for the study of high energy physics through electron-positron collisions at center-of-mass energies up to 500 GeV and luminosities up to 2 x 10{sup 34} cm{sup -2} sec{sup -1}. Meeting the ILC's goals will require an extremely sophisticated suite of beam instruments for the preservation of beam emittance, the diagnosis of optical errors and mismatches, the determination of beam properties required for particle physics purposes, and machine protection. The instrumentation foreseen for the ILC is qualitatively similar to equipment in use at other accelerator facilities in the world, but in many cases the precision, accuracy, stability, or dynamic range required by the ILC exceed what is typically available in today's accelerators. In this paper we survey the beam instrumentation requirements of the ILC and describe the system components which are expected to meet those requirements.

  17. High-yield positron systems for linear colliders

    SciTech Connect

    Clendenin, J.E.

    1989-04-01

    Linear colliders, such as the SLC, are among those accelerators for which a high-yield positron source operating at the repetition rate of the accelerator is desired. The SLC, having electron energies up to 50 GeV, presents the possibility of generating positron bunches with useful charge even exceeding that of the initial electron bunch. The exact positron yield to be obtained depends on the particular capture, transport and damping system employed. Using 31 GeV electrons impinging on a W-type converter phase-space at the target to the acceptance of the capture rf section, the SLC source is capable of producing, for every electron, up to two positrons within the acceptance of the positron damping ring. The design of this source and the performance of the positron system as built are described. Also, future prospects and limitations for high-yield positron systems are discussed. 11 refs., 5 figs., 3 tabs.

  18. Bunch compression for the TLC (TeV Linear Collider)

    SciTech Connect

    Kheifets, S.A.; Ruth, R.D.; Fieguth, T.H.

    1989-08-01

    The length of the bunch for the TeV Linear Collider (TLC) must be decreased, while simultaneously preserving its small transverse emittance. To achieve a short bunch length (/approximately/ 70 /mu/m) needed for the TLC, it is necessary to use two-step compression of a 5 mm bunch which is extracted from the damping ring. The corresponding increase of momentum spread requires that chromatic aberrations of the transport line must be corrected at least up to second order. This goal is achieved by building the compressor out of second-order achromats, which also eliminates geometric aberrations. The utilization of flat beams restricts the design to an uncoupled, mid-plane symmetric transport line. The first compression is performed by a conventional compressor. For the second, it is possible to use a 180/degree/ bend. The emittance growth due to the synchrotron radiation is kept to several percent. 10 refs., 3 tabs.

  19. Dark Current Simulation for Linear Collider Accelerator Structures

    SciTech Connect

    Ng, C.K.; Li, Z.; Zhan, X.; Srinivas, V.; Wang, J.; Ko, K.; /SLAC

    2011-08-25

    The dynamics of field-emitted electrons in the traveling wave fields of a constant gradient (tapered) disk-loaded waveguide is followed numerically. Previous simulations have been limited to constant impedance (uniform) structures for sake of simplicity since only the fields in a unit cell is needed. Using a finite element field solver on a parallel computer, the fields in the tapered structure can now be readily generated. We will obtain the characteristics of the dark current emitted from both structure types and compare the two results with and without the effect of secondary electrons. The NLC and JLC detuned structures are considered to study if dark current may pose a problem for high gradient acceleration in the next generation of Linear Colliders.

  20. Reliability and Maintainability Issues for the Next Linear Collider

    SciTech Connect

    Wilson, Zane J.; Gold, Saul L.; Koontz, Ron F.; Lavine, Ted L.; /SLAC

    2011-08-26

    Large accelerators for high energy physics research traditionally have been designed using informal best design, engineering, and management practices to achieve acceptable levels of operational availability. However, the Next Linear Collider(NLC) project presents a particular challenge for operational availability due to the unprecedented size and complexity of the accelerator systems required to achieve the physics goals of high center-of-mass energy and high luminosity. Formal reliability and maintainability analysis, design, and implementation will be required to achieve acceptable operational availability for the high energy physics research program. This paper introduces some of the basic concepts of reliability analysis and applies them to the 2.6-cm microwave power system of the two 10-km-long, 250-GeV linacs that are currently proposed for the NLC design.

  1. Proposal of the Next Incarnation of Accelerator Test Facility at KEK for the International Linear Collider

    SciTech Connect

    Araki, S.; Hayano, H.; Higashi, Y.; Honda, Y.; Kanazawa, K.; Kubo, K.; Kume, T.; Kuriki, M.; Kuroda, S.; Masuzawa, M.; Naito, T.; Okugi, T.; Sugahara, R.; Takahashi, T.; Tauchi, T.; Terunuma, N.; Toge, N.; Urakawa, J.; Vogel, V.; Yamaoka, H.; Yokoya, K.; /KEK, Tsukuba /Beijing, Inst. High Energy Phys. /Novosibirsk, IYF /Daresbury /CERN /Hiroshima U. /Orsay, LAL /LLNL, Livermore /North Carolina A-T State U. /Oxford U. /Pohang Accelerator Lab. /Queen Mary, U. of London /Royal Holloway, U. of London /DESY /SLAC /University Coll. London /Oregon U. /Tokyo U.

    2005-05-27

    To reach design luminosity, the International Linear Collider (ILC) must be able to create and reliably maintain nanometer size beams. The ATF damping ring is the unique facility where ILC emittances are possible. In this paper we present and evaluate the proposal to create a final focus facility at the ATF which, using compact final focus optics and an ILC-like bunch train, would be capable of achieving 37 nm beam size. Such a facility would enable the development of beam diagnostics and tuning methods, as well as the training of young accelerator physicists.

  2. Neutrino counting with the SLD at the Stanford Linear Collider

    SciTech Connect

    Band, H.; Bugg, W.; Chadwick, G.; Coyne, D.; Gyure, M.; Hertzbach, S.; Messner, R.; Mincer, A.; Mockett, P.; Nauenberg, U.

    1989-06-01

    One of the fundamental measurements to be made at the e/sup +/e/sup /minus// colliders, SLC and LEP, is the determination of the number of neutrino families produced in Z/sup 0/ boson decays. In the event that a fourth generation of light Dirac neutrinos exists, the experimental consequences at the Z/sup 0/ resonances are easily seen; the total width will be increased by 171 MeV over its three generation value, to be compared to the /approx/30 MeV precision that should be achievable once the systematic limit has been reached. A reasonable figure of merit for the precision of a neutrino counting measurement of 0.2 standard model generations corresponds to a Z/sup 0/ width measurement error of 35 MeV; close to the limit of anticipated experimental capability. In fact, it is highly desirable to achieve an even higher precision if possible, in order to distinguish potentially small effects due to exotic phenomena from beyond the Standard Model. This paper will address the issue of how to obtain the best measurement of the number of neutrino generations as a function of the size of the available sample of Z/sup 0/ decays. The results presented here were obtained by our study group in an attempt to understand the limitations of a realistic neutrino counting measurement with the SLD at the Stanford Linear Collider. However, many of our findings are general enough to be applicable to any e/sup +/e/sup /minus// detector designed to take data at the Z/sup 0/ resonance. 19 refs., 5 figs., 6 tabs.

  3. International Linear Collider-A Technical Progress Report

    SciTech Connect

    Elsen, Eckhard; Harrison, Mike; Hesla, Leah; Ross, Marc; Royole-Degieux, Perrine; Takahashi, Rika; Walker, Nicholas; Warmbein, Barbara; Yamamoto, Akira; Yokoya, Kaoru; Zhang, Min; /Beijing, Inst. High Energy Phys.

    2011-11-04

    The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

  4. Zeroth-order design report for the next linear collider. Volume 2

    SciTech Connect

    Raubenheimer, T.O.

    1996-05-01

    This Zeroth-Order Design Report (ZDR) for the Next Linear Collider (NLC) has been completed as a feasibility study for a TeV-scale linear collider that incorporates a room-temperature accelerator powered by rf microwaves at 11.424 GHz--similar to that presently used in the SLC, but at four times the rf frequency. The purpose of this study is to examine the complete systems of such a collider, to understand how the parts fit together, and to make certain that every required piece has been included. The ``design`` presented here is not fully engineered in any sense, but to be assured that the NLC can be built, attention has been given to a number of critical components and issues that present special challenges. More engineering and development of a number of mechanical and electrical systems remain to be done, but the conclusion of this study is that indeed the NLC is technically feasible and can be expected to reach the performance levels required to perform research at the TeV energy scale. Volume II covers the following: collimation systems; IP switch and big bend; final focus; the interaction region; multiple bunch issues; control systems; instrumentation; machine protection systems; NLC reliability considerations; NLC conventional facilities. Also included are four appendices on the following topics: An RF power source upgrade to the NLC; a second interaction region for gamma-gamma, gamma-electron; ground motion: theory and measurement; and beam-based feedback: theory and implementation.

  5. Adjustable permanent quadrupoles for the next linear collider

    SciTech Connect

    James T. Volk et al.

    2001-06-22

    The proposed Next Linear Collider (NLC) will require over 1400 adjustable quadrupoles between the main linacs' accelerator structures. These 12.7 mm bore quadrupoles will have a range of integrated strength from 0.6 to 138 Tesla, with a maximum gradient of 141 Tesla per meter, an adjustment range of +0 to {minus}20% and effective lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. In an effort to reduce costs and increase reliability, several designs using hybrid permanent magnets have been developed. Four different prototypes have been built. All magnets have iron poles and use Samarium Cobalt to provide the magnetic fields. Two use rotating permanent magnetic material to vary the gradient, one uses a sliding shunt to vary the gradient and the fourth uses counter rotating magnets. Preliminary data on gradient strength, temperature stability, and magnetic center position stability are presented. These data are compared to an equivalent electromagnetic prototype.

  6. High Reliability Prototype Quadrupole for the Next Linear Collider

    SciTech Connect

    Spencer, Cherrill M

    2001-01-04

    The Next Linear Collider (NLC) will require over 5600 magnets, each of which must be highly reliable and/or quickly repairable in order that the NLC reach its 85% overall availability goal. A multidiscipline engineering team was assembled at SLAC to develop a more reliable electromagnet design than historically had been achieved at SLAC. This team carried out a Failure Mode and Effects Analysis (FMEA) on a standard SLAC quadrupole magnet system. They overcame a number of longstanding design prejudices, producing 10 major design changes. This paper describes how a prototype magnet was constructed and the extensive testing carried out on it to prove full functionality with an improvement in reliability. The magnet's fabrication cost will be compared to the cost of a magnet with the same requirements made in the historic SLAC way. The NLC will use over 1600 of these 12.7 mm bore quadrupoles with a range of integrated strengths from 0.6 to 132 Tesla, a maximum gradient of 135 Tesla per meter, an adjustment range of 0 to -20% and core lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20% adjustment. A magnetic measurement set-up has been developed that can measure sub-micron shifts of a magnetic center. The prototype satisfied the center shift requirement over the full range of integrated strengths.

  7. High Reliability Prototype Quadrupole for the Next Linear Collider

    NASA Astrophysics Data System (ADS)

    Spencer, C. M.

    2001-01-01

    The Next Linear Collider (NLC) will require over 5600 magnets, each of which must be highly reliable and/or quickly repairable in order that the NLC reach its 85/ overall availability goal. A multidiscipline engineering team was assembled at SLAC to develop a more reliable electromagnet design than historically had been achieved at SLAC. This team carried out a Failure Mode and Effects Analysis (FMEA) on a standard SLAC quadrupole magnet system. They overcame a number of longstanding design prejudices, producing 10 major design changes. This paper describes how a prototype magnet was constructed and the extensive testing carried out on it to prove full functionality with an improvement in reliability. The magnet's fabrication cost will be compared to the cost of a magnet with the same requirements made in the historic SLAC way. The NLC will use over 1600 of these 12.7 mm bore quadrupoles with a range of integrated strengths from 0.6 to 132 Tesla, a maximum gradient of 135 Tesla per meter, an adjustment range of 0 to -20/ and core lengths from 324 mm to 972 mm. The magnetic center must remain stable to within 1 micron during the 20/ adjustment. A magnetic measurement set-up has been developed that can measure sub-micron shifts of a magnetic center. The prototype satisfied the center shift requirement over the full range of integrated strengths.

  8. Depolarization due to beam-beam interaction in electron-positron linear colliders

    SciTech Connect

    Yokoya, K. ); Chen, P. )

    1989-05-05

    We investigate two major mechanisms which induce depolarization of electron beams during beam-beam interaction in linear colliders. These are the classical spin precession under the collective field of the oncoming beam, and the spin-flip effect from beamstrahlung. Analytic formulas are derived for estimating these depolarization effects. As examples, we estimate the depolarization in the Stanford Linear Collider (SLC) and a possible future TeV linear collider (TLC). The effects are found to be negligibly small for SLC and not very large for TLC.

  9. Beam trajectory acquisition system for the arcs of the Stanford Linear Collider

    SciTech Connect

    Pellegrin, J.L.; Ross, M.C.; Scott, B.D.; Wilson, D.S.

    1987-02-01

    This report describes the beam position monitoring system of the collider arcs at the Stanford Linear Collider. This beam position monitoring system is different from others at SLAC in its large amount of hardware and its use of ungated, self-triggered electronics. All of the processing electronics are installed in the accelerator tunnel. (JDH)

  10. Science and Technology of the TESLA Electron-Positron Linear Collider

    NASA Astrophysics Data System (ADS)

    Wagner, Albrecht

    2002-07-01

    Recent analyses of the long term future of particles physics in Asia, Europe, and the U.S.A. have led to the consensus that the next major facility to be built to unravel the secrets of the micro-cosmos is an electron-positron linear collider in the energy range of 500 to 1000 GeV. This collider should be constructed in an as timely fashion as possible to overlap with the Large Hadron Collider, under construction at CERN. Here, the scientific potential and the technological aspects of the TESLA projects, a superconducting collider with an integrated X-ray laser laboratory, are summarised.

  11. HOM-Free Linear Accelerating Structure for e+ e- Linear Collider at C-Band

    SciTech Connect

    Kubo, Kiyoshi

    2003-07-07

    HOM-free linear acceleration structure using the choke mode cavity (damped cavity) is now under design for e{sup +}e{sup -} linear collider project at C-band frequency (5712 MHz). Since this structure shows powerful damping effect on most of all HOMs, there is no multibunch problem due to long range wakefields. The structure will be equipped with the microwave absorbers in each cells and also the in-line dummy load in the last few cells. The straightness tolerance for 1.8 m long structure is closer than 30 {micro}m for 25% emittance dilution limit, which can be achieved by standard machining and braising techniques. Since it has good vacuum pumping conductance through annular gaps in each cell, instabilities due to the interaction of beam with the residual-gas and ions can be minimized.

  12. The generation and acceleration of low emittance flat beams for future linear colliders

    SciTech Connect

    Raubenheimer, T.O.

    1991-11-01

    Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {gamma}{epsilon}{sub x} = 3{times}10{sup {minus}6} m-rad and {gamma}{epsilon}{sub y} = 3{times}10{sup {minus}8} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate fundamental'' limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

  13. The generation and acceleration of low emittance flat beams for future linear colliders

    SciTech Connect

    Raubenheimer, T.O.

    1991-11-01

    Many future linear collider designs call for electron and positron beams with normalized rms horizontal and vertical emittances of {gamma}{epsilon}{sub x} = 3{times}10{sup {minus}6} m-rad and {gamma}{epsilon}{sub y} = 3{times}10{sup {minus}8} m-rad; these are a factor of 10 to 100 below those observed in the Stanford Linear Collider. In this dissertation, we examine the feasibility of achieving beams with these very small vertical emittances. We examine the limitations encountered during both the generation and the subsequent acceleration of such low emittance beams. We consider collective limitations, such as wakefields, space charge effects, scattering processes, and ion trapping; and also how intensity limitations, such as anomalous dispersion, betatron coupling, and pulse-to-pulse beam jitter. In general, the minimum emittance in both the generation and the acceleration stages is limited by the transverse misalignments of the accelerator components. We describe a few techniques of correcting the effect of these errors, thereby easing the alignment tolerances by over an order of magnitude. Finally, we also calculate ``fundamental`` limitations on the minimum vertical emittance; these do not constrain the current designs but may prove important in the future.

  14. Effects and tolerances of injection jitter in the SLC and future linear colliders

    SciTech Connect

    Limberg, T.; Seeman, J.T.; Spence, W.L.

    1990-05-01

    The bunch injected into the main linac of a linear collider may have offsets in transverse angle and position, may have a phase error (longitudinal position offset) and, furthermore, may be optically mismatched. Each of these injection errors reduces the luminosity and must be held within tolerances. The effect of optical mismatches on the emittance at the end of the linac is calculated analytically. The tightest tolerances on magnetic elements stemming from these effects are listed. The phase tolerance is determined by the energy acceptance of the final focus system. It imposes tolerances to the integrated field strength of the damping ring and RTL bending magnets and the bunch compressor rf-phase. In this paper, measurements of injection jitter and the effect of betatron oscillations caused by changes of the angle or position of the incoming beam are described. These measurements were taken with BNS damping which relaxes certain tolerances by an order of magnitude. The injection jitter tolerances for a linac of the next generation are given. As an example, parameters for the Next Linear Collider (NLC) being designed at SLAC are used.

  15. DCal: A custom integrated circuit for calorimetry at the International Linear Collider

    SciTech Connect

    Hoff, James R.; Mekkaoui, Abderrazek; Yarema, Ray; Drake, Gary; Repond, Jose; /Argonne

    2005-10-01

    A research and development collaboration has been started with the goal of producing a prototype hadron calorimeter section for the purpose of proving the Particle Flow Algorithm concept for the International Linear Collider. Given the unique requirements of a Particle Flow Algorithm calorimeter, custom readout electronics must be developed to service these detectors. This paper introduces the DCal or Digital Calorimetry Chip, a custom integrated circuit developed in a 0.25um CMOS process specifically for this International Linear Collider project. The DCal is capable of handling 64 channels, producing a 1-bit Digital-to-Analog conversion of the input (i.e. hit/no hit). It maintains a 24-bit timestamp and is capable of operating either in an externally triggered mode or in a self-triggered mode. Moreover, it is capable of operating either with or without a pipeline delay. Finally, in order to permit the testing of different calorimeter technologies, its analog front end is capable of servicing Particle Flow Algorithm calorimeters made from either Resistive Plate Chambers or Gaseous Electron Multipliers.

  16. Extra neutral gauge bosons at a 5 TeV e+e- linear collider

    SciTech Connect

    Ohgaki, T.

    1999-05-01

    For a 5 TeV e{sup +}e{sup -} linear collider in the deep quantum regime, the energy loss due to beam-strahlung during the collision of the e{sup +}e{sup -} beams is expected to substantially influence the effect center-of-mass energy distribution of the colliding particles. In this paper, the author has estimated the feasibility of the measurement of the extra neutral gauge bosons Z' on the Z' pole at a 5 TeV e{sup +}e{sup -} linear collider including the effects of the beam-beam interaction.

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

    ScienceCinema

    None

    2016-07-12

    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.

  18. 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.

  19. PROGRESS WITH THE JLC/NLC X-BAND LINEAR COLLIDER DESIGN

    SciTech Connect

    Raubenheimer, Tor O

    2000-11-06

    An electron/positron linear collider with a center-of-mass energy between 0.5 and 1 TeV would be an important complement to the physics program of the LHC in the next decade. The Next Linear Collider (NLC) is being designed by a US collaboration (FNAL, LBNL, LLNL, and SLAC) which is working closely with the Japanese collaboration that is designing the Japanese Linear Collider (JLC). This paper will discuss the technical difficulties encountered as well as the changes that have been made to the NLC design over the last year. These changes include improvements to the X-band rf system as well as modifications to the beam delivery system. The net effect has been to reduce the length of the collider from about 32 km to 25 km and to reduce the number of klystrons and modulators by a factor of two. Together these lead to significant cost savings.

  20. Analysis and Control of Wakefields in X-Band Crab Cavities for Compact Linear Collider

    SciTech Connect

    Ambattu, P.K.; Burt, G.; Khan, V.F.; Jones, R.M.; Dexter, A.; Dolgashev, V.; /SLAC

    2012-04-25

    The Compact Linear Collider requires a crab cavity on each beamline prior to the interaction point to rotate the bunches before collision. The cavities are X-band travelling wave type and are located close to the final doublet of the beam delivery system. This makes the beam very sensitive to transverse momentum imparted by wakefields; hence the wakefields must be tightly controlled. Of special concerns are the orthogonal polarization of the operating mode and the fundamental monopole mode of the crab cavity. The former mode is at the same frequency as the operating mode of a cylindrically symmetric cavity and the latter one is at a lower frequency and hence is difficult to damp using a single means. In this paper major problematic modes of the crab cavity are investigated and damping requirements for them are calculated. Possibility of meeting the required wakefield control using waveguide damping and choke damping is thoroughly investigated. As a comparison, damped-detuning is also investigated.

  1. 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.

  2. A Laser-Driven Linear Collider: Sample Machine Parameters and Configuration

    SciTech Connect

    Colby, E.R.; England, R.J.; Noble, R.J.; /SLAC

    2011-05-20

    We present a design concept for an e{sup +}e{sup -} linear collider based on laser-driven dielectric accelerator structures, and discuss technical issues that must be addressed to realize such a concept. With a pulse structure that is quasi-CW, dielectric laser accelerators potentially offer reduced beamstrahlung and pair production, reduced event pileup, and much cleaner environment for high energy physics and. For multi-TeV colliders, these advantages become significant.

  3. Linear Corrugating - Final Technical Report

    SciTech Connect

    Lloyd Chapman

    2000-05-23

    Linear Corrugating is a process for the manufacture of corrugated containers in which the flutes of the corrugated medium are oriented in the Machine Direction (MD) of the several layers of paper used. Conversely, in the conventional corrugating process the flutes are oriented at right angles to the MD in the Cross Machine Direction (CD). Paper is stronger in MD than in CD. Therefore, boxes made using the Linear Corrugating process are significantly stronger-in the prime strength criteria, Box Compression Test (BCT) than boxes made conventionally. This means that using Linear Corrugating boxes can be manufactured to BCT equaling conventional boxes but containing 30% less fiber. The corrugated container industry is a large part of the U.S. economy, producing over 40 million tons annually. For such a large industry, the potential savings of Linear Corrugating are enormous. The grant for this project covered three phases in the development of the Linear Corrugating process: (1) Production and evaluation of corrugated boxes on commercial equipment to verify that boxes so manufactured would have enhanced BCT as proposed in the application; (2) Production and evaluation of corrugated boxes made on laboratory equipment using combined board from (1) above but having dual manufactures joints (glue joints). This box manufacturing method (Dual Joint) is proposed to overcome box perimeter limitations of the Linear Corrugating process; (3) Design, Construction, Operation and Evaluation of an engineering prototype machine to form flutes in corrugating medium in the MD of the paper. This operation is the central requirement of the Linear Corrugating process. Items I and II were successfully completed, showing predicted BCT increases from the Linear Corrugated boxes and significant strength improvement in the Dual Joint boxes. The Former was constructed and operated successfully using kraft linerboard as the forming medium. It was found that tensile strength and stretch

  4. Stripline design for the extraction kicker of Compact Linear Collider damping rings

    NASA Astrophysics Data System (ADS)

    Belver-Aguilar, C.; Faus-Golfe, A.; Toral, F.; Barnes, M. J.

    2014-07-01

    In the framework of the design study of future linear colliders, the Compact Linear Collider (CLIC) aims for electron-positron collisions with high luminosity at a nominal center-of-mass energy of 3 TeV. To achieve the luminosity requirements, predamping rings (PDRs) and damping rings (DRs) are required: they reduce the beam emittance before the beam is accelerated in the main linac. Several kicker systems are needed to inject and extract the beam from the PDRs and DRs. In order to achieve both low beam coupling impedance and reasonable broadband impedance matching to the electrical circuit, striplines have been chosen for the kicker elements. In this paper, we present the complete design of the striplines for the DR extraction kicker, since it is the most challenging from the field homogeneity point of view. The excellent field homogeneity required, as well as a good transmission of the high voltage pulse through the electrodes, has been achieved by choosing a novel electrode shape. With this new geometry, it has been possible to benefit from all the advantages that the most common shapes introduce separately. Furthermore, a detailed study of the different operating modes of a stripline kicker allowed the beam coupling impedance to be reduced at low frequencies: this cannot be achieved by tapering the electrodes. The optimum design of the striplines and their components has been based on studies of impedance matching, field homogeneity, power transmission, beam coupling impedance, and manufacturing tolerances. Finally, new ideas for further improvement of the performance of future striplines are reported.

  5. Photon-photon collisions at the next linear collider: Theory

    SciTech Connect

    Brodsky, S.J.

    1993-08-01

    The collisions of photons at a high energy electron-positron collider provide a comprehensive laboratory for testing QCD, electroweak interactions, and extensions of the standard model. It is expected that by using back-scattered laser beams that the effective luminosity and energy of photon-photon collisions will be comparable to that of the primary e{sup +}e{sup {minus}} collisions. In this talk, I will focus on tests of electroweak theory in photon-photon annihilation such as {gamma}{gamma} {yields} W{sup +}W{sup {minus}}, {gamma}{gamma} {yields} Higgs boson, and higher-order loop processes, such as {gamma}{gamma} {yields} {gamma}{gamma}, Z{gamma} and ZZ. Since each photon can be resolved into a W{sup +}W{sup {minus}} pair, high energy photon-photon collisions can also provide a remarkable background-free laboratory for studying WW collisions and annihilation. I also review high energy {gamma}{gamma} tests of quantum chromodynamics, such as the scaling of the photon structure function, t{bar t} production, mini-jet processes, and diffractive reactions.

  6. On the Preference of Cold RF Technology for the International Linear Collider

    SciTech Connect

    Gamp, Alexander

    2006-01-03

    On August 20th 2004 the International Technology Recommendation Panel (ITRP) released its recommendation that the Linear Collider be based on Superconducting RF Technology. Following a request of the organizers of this conference we will summarise in this article the arguments worked out and presented by the ITRP, which led to this recommendation. The main features of both RF-technologies, the favoured L-band RF system of the superconducting version of the Linear Collider and the X-band-technology anticipated for the normal-conducting alternative will be briefly described.

  7. Estimates of Hadronic Backgrounds in Future e+e- LinearColliders

    SciTech Connect

    Ohgaki, Tomomi

    1998-05-01

    We have estimated hadronic backgrounds for an e+e- linear collider at a center- of-mass energy of 5 TeV. In order to achieve a required luminosity in TeV e+ e- colliders, the high beamstrahlung parameter {Upsilon}, such as several thousands, is caused. In the high {Upsilon} regime, the {gamma}{gamma} luminosities due to the collision of beamstrahlung photons are calculated by using the CAIN code. According to the {gamma}{gamma} luminosity distribution, we have estimated the hadronic backgrounds of {gamma}{gamma} {yields} minijets based on the parton distributions of the Drees and Grassie model by the PYTHIA 5.7 code. The Japan Linear Collider (J LC-1) detector simulator is applied for selection performances in the detector.

  8. Long ion chamber systems for the SLC (Stanford Linear Collider)

    SciTech Connect

    Rolfe, J.; Gearhart, R.; Jacobsen, R.; Jenkins, T.; McComick, D.; Nelson, R.; Reagan, D.; Ross, M.

    1989-03-01

    A Panofsky Long Ion Chamber (PLIC) is essentially a gas-filled coaxial cable, and has been used to protect the Stanford Linear Accelerator from damage caused by its electron beam, and as a sensitive diagnostic tool. This old technology has been updated and has found renewed use in the SLC. PLIC systems have been installed as beam steering aids in most parts of the SLC and are a part of the system that protects the SLC from damage by errant beams in several places. 5 refs., 3 figs., 1 tab.

  9. Detectors for Linear Colliders: Tracking and Vertexing (2/4)

    ScienceCinema

    None

    2016-07-12

    Efficient and precise determination of the flavour of partons in multi-hadron final states is essential to the anticipated LC physics program. This makes tracking in the vicinity of the interaction region of great importance. Tracking extrapolation and momentum resolution are specified by precise physics requirements. The R&D; towards detectors able to meet these specifications will be discussed, together with some of their application beyond particle physics.

  10. Review of studies on conventional linear colliders in the S- and X-Band regime

    SciTech Connect

    Loew, G.A.

    1992-07-01

    This paper gives a status report on the conventional approaches to linear colliders at DESY, KEK, SLAC and INP-Protvino in the S- and X-Band regime. Critical topics are reviewed and a discussion of global issues such as future R&D requirements is included.

  11. Review of studies on conventional linear colliders in the S- and X-Band regime

    SciTech Connect

    Loew, G.A.

    1992-07-01

    This paper gives a status report on the conventional approaches to linear colliders at DESY, KEK, SLAC and INP-Protvino in the S- and X-Band regime. Critical topics are reviewed and a discussion of global issues such as future R D requirements is included.

  12. Baseline Configuration of the Cryogenic System for the International Linear Collider

    SciTech Connect

    Casas-Cubillos, J.; Claudet, S.; Parma, V.; Riddone, G.; Serio, L.; Tavian, L.; Vullierme, B.; van Weelderen, R.; Chorowski, M.; Ganni, R.; Rode, C.; Klebaner, A.; Peterson, T.; Theilacker, J.; Rousset, B.; Weisend, J.; /SLAC

    2007-06-18

    The paper discusses the main constraints and boundary conditions and describes the baseline configuration of the International Linear Collider (ILC) cryogenic system. The cryogenic layout, architecture and the cooling principle are presented. The paper addresses a plan for study and development required to demonstrate and improve the performance, to reduce cost and to attain the desired reliability.

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

    SciTech Connect

    Abe, T.; et al.

    2001-06-13

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

  14. Review of linear collider beam-beam interaction

    SciTech Connect

    Chen, P.

    1989-01-01

    Three major effects from the interaction of e/sup +/e/sup /minus// beams---disruption, beamstrahlung, and electron-positron pair creation---are reviewed. For the disruption effects we discuss the luminosity enhancement factor, the maximum and rms disruption angles, and the ''kink instability''. All the results are obtained from computer simulations. Scaling laws for the numerical results and theoretical explanations of the computer acquired phenomena are offered wherever possible. For the beamstrahlung effects we concentrate only on the final electron energy spectrum resulting from multiple photon radiation process, and the deflection angle associated with low energy particles. For the effects from electron-positron pair creation, both coherent and incoherent processes of beamstrahlung pair creation are discussed. In addition to the estimation on total number of such pairs, we also look into the energy spectrum and the deflection angle. 17 refs., 23 figs., 1 tab.

  15. Physics at TeV e sup + e sup minus linear colliders

    SciTech Connect

    Chanowitz, M.S.

    1992-01-01

    A survey is presented of the physics opportunities at TeV e{sup +}e{sup {minus}} linear colliders. Examples are given of physics that might emerge in e{sup +}e{sup {minus}} collisions and in {gamma}{gamma} collisions using the back-scattered laser technique, including {gamma}{gamma} {yields} ZZ scattering as a probe of ultraheavy quanta. The second portion of the talk focuses on physics that must emerge at or below the TeV scale--the mechanism of electroweak symmetry breaking. In particular a very rough estimate is presented of the most challenging possible signal of symmetry breaking, strong WW scattering, as a function of collider energy. A subtheme, made explicit in the concluding section, is the continuing complementarity of e{sup +}e{sup {minus}} and pp colliders in the domain of TeV physics.

  16. Physics at TeV e{sup +}e{sup {minus}} linear colliders

    SciTech Connect

    Chanowitz, M.S.

    1992-01-01

    A survey is presented of the physics opportunities at TeV e{sup +}e{sup {minus}} linear colliders. Examples are given of physics that might emerge in e{sup +}e{sup {minus}} collisions and in {gamma}{gamma} collisions using the back-scattered laser technique, including {gamma}{gamma} {yields} ZZ scattering as a probe of ultraheavy quanta. The second portion of the talk focuses on physics that must emerge at or below the TeV scale--the mechanism of electroweak symmetry breaking. In particular a very rough estimate is presented of the most challenging possible signal of symmetry breaking, strong WW scattering, as a function of collider energy. A subtheme, made explicit in the concluding section, is the continuing complementarity of e{sup +}e{sup {minus}} and pp colliders in the domain of TeV physics.

  17. Physics with linear colliders in the TeV CM energy region

    SciTech Connect

    Bulos, F.; Cook, V.; Hinchliffe, I.; Lane, K.; Pellet, D.; Perl, M.; Seiden, A.; Wiedemann, H.

    1982-07-01

    From a technical point of view a linear collider of high energy and luminosity cannot be operated economically at the present date. A series of R and D efforts in different areas are required to produce the necessary technology for an economically feasible linear collider. No fundamental limits, however, have been found as yet that would prevent us from reaching the goals outlined in this report. Most of the critical component will be tested in a real like situation once the SLC comes into operation. Beyond that much R and D is required in rf-power sources to reduce the power consumption and in high gradient accelerating structures to minimize the required real estate and linear construction costs.

  18. 2005 Final Report: New Technologies for Future Colliders

    SciTech Connect

    Peter McIntyre; Al McInturff

    2005-12-31

    This document presents an annual report on our long-term R&D grant for development of new technology for future colliders. The organizing theme of our development is to develop a compact high-field collider dipole, utilizing wind-and-react Nb3Sn coil fabrication, stress man-agement, conductor optimization, bladder preload, and flux plate suppression of magnetization multipoles. The development trail for this new technology began over four years ago with the successful testing of TAMU12, a NbTi model in which we put to a first test many of the construction details of the high-field design. We have built TAMU2, a mirror-geometry dipole containing a single coil module of the 3-module set required for the 14 Tesla design. This first Nb3Sn model was built using ITER conductor which carries much less current than high-performance conductor but enables us to prove in practice our reaction bake and impregnation strategies with ‘free’ su-perconductor. TAMU2 has been shipped to LBNL for testing. Work is beginning on the construction of TAMU3, which will contain two coil modules of the 14 Tesla design. TAMU3 has a design field of 13.5 Tesla and will enable us to fully evaluate the issues of stress management that will be important to the full design. With the completion of TAMU2 and the construction of TAMU3 the Texas A&M group ‘comes of age’ in the family of superconducting magnet R&D laboratories. We have completed the phase of developing core technologies and fixtures and entered the phase of building and testing a succession of model dipoles that each build incrementally upon a proven core design.

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

    NASA Astrophysics Data System (ADS)

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

    2015-11-01

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

  20. 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.

  1. Revealing Fundamental Interactions: the Role of Polarized Positrons and Electrons at the Linear Collider

    SciTech Connect

    Moortgat-Pick, G.; Abe, T.; Alexander, G.; Ananthanarayan, B.; Babich, A.A.; Bharadwaj, V.; Barber, D.; Bartl, A.; Brachmann, A.; Chen, S.; Clarke, J.; Clendenin, J.E.; Dainton, J.; Desch, K.; Diehl, M.; Dobos, B.; Dorland, T.; Eberl, H.; Ellis, John R.; Flottman, K.; Frass, H.; /CERN /Durham U., IPPP /Colorado U. /Tel-Aviv U. /Bangalore, Indian Inst. Sci. /Gomel State Tech. U. /SLAC /DESY /Vienna U. /Daresbury /Liverpool U. /Freiburg U. /Vienna, OAW /Wurzburg U. /Fermilab /Uppsala U. /Waseda U., RISE /Warsaw U. /Bonn U. /Aachen, Tech. Hochsch. /Cornell U., Phys. Dept.

    2005-07-06

    The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.

  2. The Role of polarized positrons and electrons in revealing fundamental interactions at the linear collider

    SciTech Connect

    Moortgat-Pick, G.; Abe, T.; Alexander, G.; Ananthanarayan, B.; Babich, A.A.; Bharadwaj, V.; Barber, D.; Bartl, A.; Brachmann, A.; Chen, S.; Clarke, J.; Clendenin, J.E.; Dainton, J.; Desch, K.; Diehl, M.; Dobos, B.; Dorland, T.; Eberl, H.; Ellis, John R.; Flottman, K.; Frass, H.; /CERN /Durham U., IPPP /Colorado U. /Tel-Aviv U. /Bangalore, Indian Inst. Sci. /Gomel State Tech. U. /SLAC /DESY /Vienna U. /Daresbury /Liverpool U. /Freiburg U. /Vienna, OAW /Wurzburg U. /Fermilab /Uppsala U. /Waseda U., RISE /Warsaw U. /Bonn U. /Aachen, Tech. Hochsch. /Cornell U., Phys. Dept.

    2005-07-01

    The proposed International Linear Collider (ILC) is well-suited for discovering physics beyond the Standard Model and for precisely unraveling the structure of the underlying physics. The physics return can be maximized by the use of polarized beams. This report shows the paramount role of polarized beams and summarizes the benefits obtained from polarizing the positron beam, as well as the electron beam. The physics case for this option is illustrated explicitly by analyzing reference reactions in different physics scenarios. The results show that positron polarization, combined with the clean experimental environment provided by the linear collider, allows to improve strongly the potential of searches for new particles and the identification of their dynamics, which opens the road to resolve shortcomings of the Standard Model. The report also presents an overview of possible designs for polarizing both beams at the ILC, as well as for measuring their polarization.

  3. 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.

  4. A modified post damping ring bunch compressor beamline for the TESLA linear collider

    SciTech Connect

    Philippe R.-G. Piot; Winfried Decking

    2004-03-23

    We propose a modified bunch compressor beamline, downstream of the damping ring, for the TESLA linear collider. This modified beamline uses a third harmonic radio-frequency section based on the 3.9 GHz superconducting cavity under development at Fermilab. In our design the beam deceleration is about {approx}50 MeV instead of {approx}450 MeV in the original design proposed.

  5. Overview and Actual Understanding of the Electron Cloud Effect and Instabilities in the Future Linear Colliders

    SciTech Connect

    Pivi, M.

    2004-12-03

    The electron cloud is potentially an important effect in linear colliders. Many of the effects have been evaluated. Actions to suppress the electron cloud are required for the GLC/NLC positron main damping ring (MDR or DR) and the low emittance transport lines as well as for the TESLA damping ring. There is an ongoing R&D program studying a number of possible remedies to reduce the secondary electron yield below that required.

  6. Simulator for the Linear Collider (SLIC): a Tool for ILC Detector Simulations

    SciTech Connect

    Graf, N.; McCormick, J.; /SLAC

    2007-02-13

    The Simulator for the Linear Collider (SLIC) is a detector simulation program based on the GEANT4 toolkit. It is intended to enable end users to easily model detector concepts by providing the ability to fully describe detectors using plain text files read in by a common executable at runtime. The detector geometry, typically the most complex part of a detector simulation, is described at runtime using the Linear Collider Detector Description (LCDD). This system allows end users to create complex detector geometries in a standard XML format rather than procedural code such as C++. The LCDD system is based on the Geometry Description Markup Language (GDML) from the LHC Applications Group (LCG). The geometry system facilitates the study of different full detector design and their variations. SLIC uses the StdHep format to read input created by event generators and outputs events in the Linear Collider IO (LCIO) format. The SLIC package provides a binding to GEANT4 and many additional commands and features for the end user.

  7. Proceedings of the workshop on new kinds of positron sources for linear colliders

    SciTech Connect

    Clendenin, J.; Nixon, R.

    1997-06-01

    It has been very clear from the beginning of studies for future linear colliders that the conventional positron source approach, as exemplified by the SLC source, is pushing uncomfortably close to the material limits of the conversion target. Nonetheless, since this type of positron source is better understood and relatively inexpensive to build, it has been incorporated into the initial design studies for the JLC/NLC. New ideas for positron sources for linear colliders have been regularly reported in the literature and at accelerator conferences for at least a decade, and indeed the recirculation scheme associated with the VLEPP design is nearly two decades old. Nearly all the new types of positron sources discussed in this workshop come under the heading of crystals (or channeling), undulators, and Compton. Storage ring and nuclear reactor sources were not discussed. The positron source designs that were discussed have varying degrees of maturity, but except for the case of crystal sources, where proof of principle experiments have been undertaken, experimental results are missing. It is hoped that these presentations, and especially the recommendations of the working groups, will prove useful to the various linear collider groups in deciding if and when new experimental programs for positron sources should be undertaken.

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

    NASA Astrophysics Data System (ADS)

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

    2012-04-01

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

  9. Construction and performance of a permanent earth anchor (tieback) system for the Stanford Linear Collider

    SciTech Connect

    Obergfell, M.N.

    1987-02-01

    The Stanford Linear Collider is the newest addition to the high-energy physics research complex at the Stanford Linear Accelerator Center. One of the many unique features of this project is the large, underground pit, where massive particle detectors will study the collision of subatomic particles. The large, open pit utilizes nearly 600 permanent earth anchors (tiebacks) for the support of the 56 ft (17 m) high walls, and is one of the largest applications of tiebacks for permanent support of a structure. This paper examines the use of tiebacks on this project with emphasis on their installation and performance.

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

    SciTech Connect

    Raubenheimer, T.O.

    1996-05-01

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

  11. Relativistic-klystron two-beam accelerator as a power source for future linear colliders

    SciTech Connect

    Anderson, D E; Eylon, S; Henestroza, E; Houck, T L; Lidia, M; Vanecek, D L; Westenskow, G A; Yu, S S

    1998-10-05

    The technical challenge for making two-beam accelerators into realizable power sources for high-energy colliders lies in the creation of the drive beam and in its propagation over long distances through multiple extraction sections. This year we have been constructing a 1.2&A, l-MeV, induction gun for a prototype relativistic klystron two-beam accelerator (RK-TBA). The electron source will be a 8.9 cm diameter, thermionic, flat-surface cathode with a maximum shroud field stress of approximately 165 kV/cm. Additional design parameters for the injector include a pulse length of over 150-ns flat top (1% energy variation), and a normalized edge emittance of less than 300 pi-mm-n-n. The prototype accelerator will be used to study physics, engineering, and costing issues involved in the application of the RK-TBA concept to linear colliders. We have also been studying optimization parameters, such as frequency, for the application of the RK-TBA concept to multi-TeV linear colliders. As an rf power source the RK-TBA scales favorably up to frequencies around 35 GHz. An overview of this work with details of the design and performance of the prototype injector, beam line, and diagnostics will be presented.

  12. Experimental validation of a novel compact focusing scheme for future energy-frontier linear lepton colliders.

    PubMed

    White, G R; Ainsworth, R; Akagi, T; Alabau-Gonzalvo, J; Angal-Kalinin, D; Araki, S; Aryshev, A; Bai, S; Bambade, P; Bett, D R; Blair, G; Blanch, C; Blanco, O; Blaskovic-Kraljevic, N; Bolzon, B; Boogert, S; Burrows, P N; Christian, G; Corner, L; Davis, M R; Faus-Golfe, A; Fukuda, M; Gao, J; García-Morales, H; Geffroy, N; Hayano, H; Heo, A Y; Hildreth, M; Honda, Y; Huang, J Y; Hwang, W H; Iwashita, Y; Jang, S; Jeremie, A; Kamiya, Y; Karataev, P; Kim, E S; Kim, H S; Kim, S H; Kim, Y I; Komamiya, S; Kubo, K; Kume, T; Kuroda, S; Lam, B; Lekomtsev, K; Liu, S; Lyapin, A; Marin, E; Masuzawa, M; McCormick, D; Naito, T; Nelson, J; Nevay, L J; Okugi, T; Omori, T; Oroku, M; Park, H; Park, Y J; Perry, C; Pfingstner, J; Phinney, N; Rawankar, A; Renier, Y; Resta-López, J; Ross, M; Sanuki, T; Schulte, D; Seryi, A; Shevelev, M; Shimizu, H; Snuverink, J; Spencer, C; Suehara, T; Sugahara, R; Takahashi, T; Tanaka, R; Tauchi, T; Terunuma, N; Tomás, R; Urakawa, J; Wang, D; Warden, M; Wendt, M; Wolski, A; Woodley, M; Yamaguchi, Y; Yamanaka, T; Yan, J; Yokoya, K; Zimmermann, F

    2014-01-24

    A novel scheme for the focusing of high-energy leptons in future linear colliders was proposed in 2001 [P. Raimondi and A. Seryi, Phys. Rev. Lett. 86, 3779 (2001)]. This scheme has many advantageous properties over previously studied focusing schemes, including being significantly shorter for a given energy and having a significantly better energy bandwidth. Experimental results from the ATF2 accelerator at KEK are presented that validate the operating principle of such a scheme by demonstrating the demagnification of a 1.3 GeV electron beam down to below 65 nm in height using an energy-scaled version of the compact focusing optics designed for the ILC collider.

  13. Online beam energy measurement of Beijing electron positron collider II linear accelerator

    NASA Astrophysics Data System (ADS)

    Wang, S.; Iqbal, M.; Liu, R.; Chi, Y.

    2016-02-01

    This paper describes online beam energy measurement of Beijing Electron Positron Collider upgraded version II linear accelerator (linac) adequately. It presents the calculation formula, gives the error analysis in detail, discusses the realization in practice, and makes some verification. The method mentioned here measures the beam energy by acquiring the horizontal beam position with three beam position monitors (BPMs), which eliminates the effect of orbit fluctuation, and is much better than the one using the single BPM. The error analysis indicates that this online measurement has further potential usage such as a part of beam energy feedback system. The reliability of this method is also discussed and demonstrated in this paper.

  14. Study of radio frequency breakdown in pressurized L-band waveguide for the International Linear Collider

    NASA Astrophysics Data System (ADS)

    Wang, Faya; Adolphsen, Chris; Nantista, Christopher

    2013-09-01

    An L-band (1.3 GHz) radio frequency (rf) waveguide system was assembled at SLAC to test components of a high power distribution scheme proposed for the International Linear Collider (ILC). All parts were made of aluminum and pressurized with dry nitrogen. The rf breakdown rate measured in this resonantly powered system is presented as a function of field level at different gas pressures and rf pulse widths (typically, only breakdown thresholds are reported.). The data are compared to predictions of a simple model which relates the breakdown phenomenon to the rate at which the free electron density builds in the gas.

  15. Double Higgs production in the Two Higgs Doublet Model at the linear collider

    SciTech Connect

    Arhrib, Abdesslam; Benbrik, Rachid; Chiang, C.-W.

    2008-04-21

    We study double Higgs-strahlung production at the future Linear Collider in the framework of the Two Higgs Doublet Models through the following channels: e{sup +}e{sup -}{yields}{phi}{sub i}{phi}{sub j}Z, {phi}{sub i} = h deg., H deg., A deg. All these processes are sensitive to triple Higgs couplings. Hence observations of them provide information on the triple Higgs couplings that help reconstructing the scalar potential. We discuss also the double Higgs-strahlung e{sup +}e{sup -}{yields}h deg. h deg. Z in the decoupling limit where h deg. mimics the SM Higgs boson.

  16. Survey of top quark polarization at a polarized linear e{sup +}e{sup -} collider

    SciTech Connect

    Groote, S.; Koerner, J. G.; Melic, B.; Prelovsek, S.

    2011-03-01

    We discuss in detail top quark polarization in above-threshold (tt) production at a polarized linear e{sup +}e{sup -} collider. We pay particular attention to the minimization and maximization of the polarization of the top quark by tuning the longitudinal polarization of the e{sup +} and e{sup -} beams. The polarization of the top quark is calculated in full next-to-leading order QCD. We also discuss the beam polarization dependence of the longitudinal spin-spin correlations of the top and antitop quark spins.

  17. The International Linear Collider Technical Design Report - Volume 1: Executive Summary

    SciTech Connect

    Behnke, Ties; Brau, James E.; Foster, Brian; Fuster, Juan; Harrison, Mike; Paterson, James McEwan; Peskin, Michael; Stanitzki, Marcel; Walker, Nicholas; Yamamoto, Hitoshi

    2013-06-26

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

  18. The International Linear Collider Technical Design Report - Volume 3.II: Accelerator Baseline Design

    SciTech Connect

    Adolphsen, Chris

    2013-06-26

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

  19. The International Linear Collider Technical Design Report - Volume 3.I: Accelerator \\& in the Technical Design Phase

    SciTech Connect

    Adolphsen, Chris

    2013-06-26

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

  20. High-Power Multimode X-Band RF Pulse Compression System for Future Linear Colliders

    SciTech Connect

    Tantawi, S.G.; Nantista, C.D.; Dolgashev, V.A.; Pearson, C.; Nelson, J.; Jobe, K.; Chan, J.; Fant, K.; Frisch, J.; Atkinson, D.; /LLNL, Livermore

    2005-08-10

    We present a multimode X-band rf pulse compression system suitable for a TeV-scale electron-positron linear collider such as the Next Linear Collider (NLC). The NLC main linac operating frequency is 11.424 GHz. A single NLC rf unit is required to produce 400 ns pulses with 475 MW of peak power. Each rf unit should power approximately 5 m of accelerator structures. The rf unit design consists of two 75 MW klystrons and a dual-moded resonant-delay-line pulse compression system that produces a flat output pulse. The pulse compression system components are all overmoded, and most components are designed to operate with two modes. This approach allows high-power-handling capability while maintaining a compact, inexpensive system. We detail the design of this system and present experimental cold test results. We describe the design and performance of various components. The high-power testing of the system is verified using four 50 MW solenoid-focused klystrons run off a common 400 kV solid-state modulator. The system has produced 400 ns rf pulses of greater than 500 MW. We present the layout of our system, which includes a dual-moded transmission waveguide system and a dual-moded resonant line (SLED-II) pulse compression system. We also present data on the processing and operation of this system, which has set high-power records in coherent and phase controlled pulsed rf.

  1. Diffusion bonding and brazing of high purity copper for linear collider accelerator structures

    NASA Astrophysics Data System (ADS)

    Elmer, J. W.; Klingmann, J.; van Bibber, K.

    2001-05-01

    Diffusion bonding and brazing of high purity copper were investigated to develop procedures for joining precision machined copper components for the Next Linear Collider (NLC). Diffusion bonds were made over a range of temperatures from 400 °C to 1000 °C, under two different loading conditions [3.45 kPa (0.5 psi) and 3.45 MPa (500 psi)], and on two different diamond machined surface finishes. Brazes were made using pure silver, pure gold, and gold-nickel alloys, and different heating rates produced by both radiation and induction heating. Braze materials were applied by both physical vapor deposition (PVD) and conventional braze alloy shims. Results of the diffusion bonding experiments showed that bond strengths very near that of the copper base metal could be made at bonding temperatures of 700 °C or higher at 3.45 MPa bonding pressure. At lower temperatures, only partial strength diffusion bonds could be made. At low bonding pressures (3.45 kPa), full strength bonds were made at temperatures of 800 °C and higher, while no bonding (zero strength) was observed at temperatures of 700 °C and lower. Observations of the fracture surfaces of the diffusion bonded samples showed the effects of surface finish on the bonding mechanism. These observations clearly indicate that bonding began by point asperity contact, and flatter surfaces resulted in a higher percentage of bonded area under similar bonding conditions. Results of the brazing experiments indicated that pure silver worked very well for brazing under both conventional and high heating rate scenarios. Similarly, pure silver brazed well for both the PVD layers and the braze alloy shims. The gold and gold-containing brazes had problems, mainly due to the high diffusivity of gold in copper. These problems led to the necessity of overdriving the temperature to ensure melting, the presence of porosity in the joint, and very wide braze joints. Based on the overall findings of this study, a two-step joining method

  2. Detection of heavy charged Higgs bosonsin e+ e- -> t b H- production at future Linear Colliders

    NASA Astrophysics Data System (ADS)

    Moretti, S.

    2004-05-01

    Heavy charged Higgs bosons (H^±) of a Type II 2-Higgs doublet model (2HDM) can be detected at future electron-positron Linear Colliders (LCs) even when their mass is larger than half the collider energy. The single Higgs mode e^ + e^-to tbar b H^- + {c.c.} to 4b + {j}{j} + ell + pT^{miss} (where j represents a jet and with ell = e,μ) contributes to extend the discovery reach of H^± states into the mass region M_{H^±}gtrsim sqrt s/2, where the well studied pair production channel e^ + e^-to H^-H^ + is no longer available. With a technique that allows one to reconstruct the neutrino four-momentum in the decay tto b W^ + to b ell^ + ν, one can suppress the initially overwhelming main irreducible background due to e^ + e^-to tbar t bbar b (via a gluon splitting into bbar b pairs) to a negligible level. However, for currently foreseen luminosities, one can establish a statistically significant H^± signal only over a rather limited mass region, of 20 GeV or so, beyond M_{H^±}≈ sqrt s/2, for very large or very small values of tanβ and provided high b-tagging efficiency can be achieved.

  3. 50-MW X-band klystron sources for the next generation of linear colliders

    SciTech Connect

    Caryotakis, G.; Eppley, K.; Fant, K.; Fowkes, R.; Phillips, R.; Tantawi, S.; Vlieks, A.; Wright, E.

    1994-06-01

    The first in a new series of high-power pulsed klystrons has been tested with the following results: Frequency = 11.4 GHz, beam voltage = 415 kV, power output = 51 MW, pulse length = 1.5 {mu}s, and efficiency = 37%. Several tubes of this type will be used in the Next Linear Collider Test Accelerator (NLCTA) at SLAC. The rf performance of the klystron, which employs a standing-wave extended-interaction output circuit, is closely approximated by simulations performed with the SLAC CONDOR code. The same code predicts considerably higher efficiency, using a traveling-wave output circuit. A klystron with such a circuit will be constructed in the future. Another klystron is also planned in which beam confinement is accomplished by a periodic permanent magnet (PPM) stack, for which simulations also predict good performance.

  4. State of the art in electromagnetic modeling for the Compact Linear Collider

    SciTech Connect

    Candel, Arno; Kabel, Andreas; Lee, Lie-Quan; Li, Zenghai; Ng, Cho; Schussman, Greg; Ko, Kwok; /SLAC

    2009-07-10

    SLAC's Advanced Computations Department (ACD) has developed the parallel 3D electromagnetic time-domain code T3P for simulations of wakefields and transients in complex accelerator structures. T3P is based on state-of-the-art Finite Element methods on unstructured grids and features unconditional stability, quadratic surface approximation and up to 6th-order vector basis functions for unprecedented simulation accuracy. Optimized for large-scale parallel processing on leadership supercomputing facilities, T3P allows simulations of realistic 3D structures with fast turn-around times, aiding the design of the next generation of accelerator facilities. Applications include simulations of the proposed two-beam accelerator structures for the Compact Linear Collider (CLIC) - wakefield damping in the Power Extraction and Transfer Structure (PETS) and power transfer to the main beam accelerating structures are investigated.

  5. Radiation calculations and shielding considerations for the design of the Next Linear Collider

    SciTech Connect

    Nelson, W.R.; Rokni, S.H.; Vylet, V.

    1996-11-01

    The authors describe some of the work that they have done as a contribution to the Next Linear Collider (NLC) Zeroth-Order Design Report (ZDR), with specific emphasis placed on radiation-protection issues. However, because of the very nature of this machine--namely, extremely-small beam spots of high intensity--a new approach in accelerator radiation-protection philosophy appears to be warranted. Accordingly, the presentation will first take a look at recent design studies directed at protecting the machine itself, since this has resulted in a much better understanding of the very short exposure times involved whenever beam is lost and radiation sources are created. At the end of the paper, the authors suggest a Beam Containment System (BCS) that would provide an independent, redundant guarantee that exposure times are, indeed, kept very short. This, in turn, has guided them in the determination of the transverse shield thickness for the machine.

  6. The Higgs sector of the minimal B- L model at future Linear Colliders

    NASA Astrophysics Data System (ADS)

    Basso, Lorenzo; Moretti, Stefano; Pruna, Giovanni Marco

    2011-08-01

    We investigate the phenomenology of the Higgs sector of the minimal B- L extension of the Standard Model at a future e + e - Linear Collider. We consider the discovery potential of both a sub-TeV and a multi-TeV machine. We show that, within such a theoretical scenario, several novel production and decay channels involving the two physical Higgs states, precluded at the LHC, could experimentally be accessed at such machines. Amongst these, several Higgs signatures have very distinctive features with respect to those of other models with enlarged Higgs sector, as they involve interactions of Higgs bosons between themselves, with Z' bosons as well as with heavy neutrinos. In particular, we present the scope of the Z' strahlung process for single and double Higgs production, the only suitable mechanism enabling one to access an almost decoupled heavy scalar state (therefore outside the LHC range).

  7. Choke-mode damped structure design for the Compact Linear Collider main linac

    NASA Astrophysics Data System (ADS)

    Zha, Hao; Shi, Jiaru; Chen, Huaibi; Grudiev, Alexej; Wuensch, Walter; Tang, Chuanxiang; Huang, Wenhui

    2012-12-01

    Choke-mode damped structures are being studied as an alternative design to waveguide damped structures for the main linac of the Compact Linear Collider (CLIC). Choke-mode structures have the potential for lower pulsed temperature rise and simpler and less expensive fabrication. An equivalent circuit model based on transmission line theory for higher-order-mode damping is presented. Using this model, a new choke geometry is proposed and the wakefield performance is verified using Gdfidl. This structure has a comparable wakefield damping effect to the baseline design which uses waveguide damping. A prototype structure with the same iris dimensions and accelerating gradient as the nominal CLIC design, but with the new choke geometry, has been designed for high-power tests.

  8. Ion Effects in the Electron Damping Ring of the International Linear Collider

    SciTech Connect

    Wang, L.; Raubenheimer, T.; Wolski, A.; /Liverpool U.

    2006-07-17

    Ion-induced beam instabilities and tune shifts are critical issues for the electron damping ring of the International Linear Collider (ILC). To avoid conventional ion trapping, a long gap is introduced in the electron beam by omitting a number of successive bunches out of a long train. However, the beam can still suffer from the fast ion instability, driven by ions that last only for a single passage of the electron bunches. Our study shows that the ion effects can be significantly mitigated by using multiple gaps, so that the stored beam consists of a number of relatively short bunch trains. The ion effects in the ILC damping rings are investigated using both analytical and numerical methods.

  9. Fine Grained Silicon-Tungsten Calorimetry for a Linear Collider Detector

    SciTech Connect

    Strom, D.; Frey, R.; Breidenbach, M.; Freytag, D.; Graf, N.; Haller, G.; Milgrome, O.; Radeka, V.; /Brookhaven

    2006-02-08

    A fine grained silicon-tungsten calorimeter is ideal for use as the electromagnetic calorimeter in a linear collider detector optimized for particle-flow reconstruction. We are designing a calorimeter that is based on readout chips which are bump bonded to the silicon wafers that serve as the active medium in the calorimeter. By using integrated electronics we plan to demonstrate that fine granularity can be achieved at a reasonable price. Our design minimizes the gap between tungsten layers leading to a small Moliere radius, an important figure of merit for particle-flow detectors. Tests of the silicon detectors to be used in a test beam prototype as well as timing measurements based on similar silicon detectors are discussed.

  10. 600 kV modulator design for the SLAC Next Linear Collider Test Accelerator

    SciTech Connect

    Harris, K.; de Lamare, J.; Nesterov, V.; Cassel, R.

    1992-07-01

    Preliminary design for the SLAC Next Linear Collider Test Accelerator (NLCTA) requires a pulse power source to produce a 600 kV, 600 A, 1.4 {mu}s, 0.1% flat top pulse with rise and fall times of approximately 100 ns to power an X-Band klystron with a microperveance of 1.25 at {approx} 100 MW peak RF power. The design goals for the modulator, including those previously listed, are peak modulator pulse power of 340 MW operating at 120 Hz. A three-stage darlington pulse-forming network, which produces a >100 kV, 1.4 {mu}s pulse, is coupled to the klystron load through a 6:1 pulse transformer. Careful consideration of the transformer leakage inductance, klystron capacitance, system layout, and component choice is necessary to produce the very fast rise and fall times at 600 kV operating continuously at 120 Hz.

  11. Investigation into electron cloud effects in the International Linear Collider positron damping ring

    SciTech Connect

    Crittenden, J. A.; Conway, J.; Dugan, G. F.; Palmer, M. A.; Rubin, D. L.; Shanks, J.; Sonnad, K. G.; Boon, L.; Harkay, K.; Ishibashi, T.; Furman, M. A.; Guiducci, S.; Pivi, M. T. F.; Wang, L.

    2014-03-01

    We report modeling results for electron cloud buildup and instability in the International Linear Collider positron damping ring. Updated optics, wiggler magnets, and vacuum chamber designs have recently been developed for the 5 GeV, 3.2-km racetrack layout. An analysis of the synchrotron radiation profile around the ring has been performed, including the effects of diffuse and specular photon scattering on the interior surfaces of the vacuum chamber. The results provide input to the cloud buildup simulations for the various magnetic field regions of the ring. The modeled cloud densities thus obtained are used in the instability threshold calculations. We conclude that the mitigation techniques employed in this model will suffice to allow operation of the damping ring at the design operational specifications

  12. Physics goals for the planned next linear collider engineering test facility

    SciTech Connect

    Courtlandt L Bohn et al.

    2001-06-26

    The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well as of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.

  13. Physics goals for the planned next linear collider engineering test facility.

    SciTech Connect

    Bohn, C.; Michelotti, L.; Ostiguy, J.-F.; Syphers, M.; Bluem, H.; Todd, A.; Gai, W.; Power, J.; Simpson, J.; Raubenheimer, T.

    2001-07-17

    The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well as of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.

  14. Physics Goals for the Planned Next Linear Collider Engineering Test Facility

    SciTech Connect

    Raubenheimer, Tor O

    2001-10-02

    The Next Linear Collider (NLC) Collaboration is planning to construct an Engineering Test Facility (ETF) at Fermilab. As presently envisioned, the ETF would comprise a fundamental unit of the NLC main linac to include X-band klystrons and modulators, a delay-line power-distribution system (DLDS), and NLC accelerating structures that serve as loads. The principal purpose of the ETF is to validate stable operation of the power-distribution system, first without beam, then with a beam having the NLC pulse structure. This paper concerns the possibility of configuring and using the ETF to accelerate beam with an NLC pulse structure, as well as of doing experiments to measure beam-induced wakefields in the rf structures and their influence back on the beam.

  15. Design and optimization of Compact Linear Collider main linac accelerating structure

    NASA Astrophysics Data System (ADS)

    Zha, Hao; Grudiev, Alexej

    2016-11-01

    The Compact Linear Collider (CLIC) main linac uses waveguide damped structure as its baseline design. The current baseline structure design written in the CLIC Conceptual Design Report is named "CLIC-G." Recent activities on the CLIC-G design including high power tests on structure prototypes and the study of machining cost assessment had raised the need of reoptimizing the structure design to minimize the machining cost and the pulse surface temperature rise. This work presents optimization of the structure geometry, high-order-mode (HOM) damping loads and the design of a HOM-free power splitter for the input coupler. Compared to the current baseline design CLIC-G, the new structure design reduced the pulse surface temperature rise, input power and manufacturing cost and achieves better suppression to the long range transverse wakefield. Cell disks and damping loads for the new structure design are also more compact than those of the CLIC-G design.

  16. Exploring the top-Higgs FCNC couplings at polarized linear colliders with top spin observables

    NASA Astrophysics Data System (ADS)

    Melić, Blaženka; Patra, Monalisa

    2017-01-01

    We study the nature of flavor changing neutral couplings of the top quark with the Higgs boson and the up/charm quark in the toverline{t} production at linear colliders. There are previous bounds on such tqH couplings at both, linear and hadronic colliders, with the assumption that the top couples equally to the left and the right handed fermions. In this paper we examine chirality of the tqH coupling and construct different observables which will be sensitive to it. The kinematics of the emitted q from t → qH in toverline{t} production is discussed and it was found that the polar angle distribution of q is sensitive to the chiral nature of tqH couplings. The observables in the context of top-antitop spin correlations, which are sensitive to new physics in the top decay are considered using different spin-quantization bases. It was found that in particular the off-diagonal basis can be useful to distinguish among the chiral tqH couplings. The sensitivity of the unpolarized ILC in probing the couplings at the 3 σ level at √{s}=500 GeV and ℒ = 500 fb-1 is also studied, resulting in predicted BR( t → qH) < 1 .19 × 10-3. This limit is further improved to BR( t → qH) < 8 .84 × 10-4 with the inclusion of initial beam polarization of left handed electrons and right handed positrons.

  17. Final Cooling For a High-luminosity High-Energy Lepton Collider

    SciTech Connect

    Neuffer, D.; Sayed, H.; Hart, T.; Summers, D.

    2015-05-01

    The final cooling system for a high-energy high-luminosity heavy lepton collider requires reduction of the transverse emittance εt by an order of magnitude to ~0.00003 m (rms, N), while allowing longitudinal emittance εL to increase to ~0.1m. In the present baseline approach, this is obtained by transverse cooling of low-energy muons within a sequence of high-field solenoids with low-frequency rf systems. Recent studies of such systems are presented. Since the final cooling steps are mostly emittance exchange, a variant form of that final system can be obtained by a round to flat transform in x-y, with transverse slicing of the enlarged flat transverse dimension followed by longitudinal recombination of the sliced bunchlets. Other variants are discussed. More explicit emittance exchange can greatly reduce the cost of a final cooling system.

  18. Interim report on the Global Design Effort Global International Linear Collider (ILC) R&D

    SciTech Connect

    Harrison, M.

    2011-04-30

    The International Linear Collider: A Technical Progress Report marks the halfway point towards the Global Design Effort fulfilling its mandate to follow up the ILC Reference Design Report with a more optimised Technical Design Report (TDR) by the end of 2012. The TDR will be based on much of the work reported here and will contain all the elements needed to propose the ILC to collaborating governments, including a technical design and implementation plan that are realistic and have been better optimised for performance, cost and risk. We are on track to develop detailed plans for the ILC, such that once results from the Large Hadron Collider (LHC) at CERN establish the main science goals and parameters of the next machine, we will be in good position to make a strong proposal for this new major global project in particle physics. The two overriding issues for the ILC R&D programme are to demonstrate that the technical requirements for the accelerator are achievable with practical technologies, and that the ambitious physics goals can be addressed by realistic ILC detectors. This GDE interim report documents the impressive progress on the accelerator technologies that can make the ILC a reality. It highlights results of the technological demonstrations that are giving the community increased confidence that we will be ready to proceed with an ILC project following the TDR. The companion detector and physics report document likewise demonstrates how detector designs can meet the ambitious and detailed physics goals set out by the ILC Steering Committee. LHC results will likely affect the requirements for the machine design and the detectors, and we are monitoring that very closely, intending to adapt our design as those results become available.

  19. Wedge Absorbers for Final Cooling for a High-Energy High-Luminosity Lepton Collider

    SciTech Connect

    Neuffer, David; Mohayai, Tanaz; Snopok, Pavel; Summers, Don

    2016-06-01

    A high-energy high-luminosity muon collider scenario requires a "final cooling" system that reduces transverse emittance to ~25 microns (normalized) while allowing longitudinal emittance increase. Ionization cooling using high-field solenoids (or Li Lens) can reduce transverse emittances to ~100 microns in readily achievable configurations, confirmed by simulation. Passing these muon beams at ~100 MeV/c through cm-sized diamond wedges can reduce transverse emittances to ~25 microns, while increasing longitudinal emittance by a factor of ~5. Implementation will require optical matching of the exiting beam into downstream acceleration systems.

  20. Discriminating between Z'-boson effects and effects of anomalous gauge couplings in the double production of W ± bosons at a linear collider

    NASA Astrophysics Data System (ADS)

    Andreev, Vasili V.; Pankov, A. A.

    2013-06-01

    The potential of the International Linear electron-positron Collider (ILC) for seeking, in the annihilation production of W ±-boson pairs, signals induced by new neutral gauge bosons predicted by models belonging to various classes and featuring an extended gauge sector is studied. Limits that will be obtained at ILC for the parameters and masses of Z' bosons are compared with present-day and future data from the Large Hadron Collider (LHC). The possibility of discriminating between the effects of Z-Z' mixing and signals induced by anomalous gauge couplings (AGC) is demonstrated within theoretically motivated trilinear gauge models involving several free anomalous parameters. It is found that the sensitivity of ILC to the effects of Z-Z' mixing in the process e + e - → W + W - and its ability to discriminate between these two new-physics scenarios, Z' and AGC, become substantially higher upon employing polarized initial ( e + e -) and final ( W ±) states.

  1. The E166 experiment: Development of an Undulator-Based Polarized Positron Source for the International Linear Collider

    SciTech Connect

    Kovermann, J.; Stahl, A.; Mikhailichenko, A.A.; Scott, D.; Moortgat-Pick, G.A.; Gharibyan, V.; Pahl, P.; Poschl, R.; Schuler, K.P.; Laihem, K.; Riemann, S.; Schalicke, A.; Dollan, R.; Kolanoski, H.; Lohse, T.; Schweizer, T.; McDonald, K.T.; Batygin, Y.; Bharadwaj, V.; Bower, G.; Decker, F.J.; /SLAC /Tel Aviv U. /Tennessee U.

    2011-11-14

    A longitudinal polarized positron beam is foreseen for the international linear collider (ILC). A proof-of-principle experiment has been performed in the final focus test beam at SLAC to demonstrate the production of polarized positrons for implementation at the ILC. The E166 experiment uses a 1 m long helical undulator in a 46.6 GeV electron beam to produce a few MeV photons with a high degree of circular polarization. These photons are then converted in a thin target to generate longitudinally polarized e{sup +} and e{sup -}. The positron polarization is measured using a Compton transmission polarimeter. The data analysis has shown asymmetries in the expected vicinity of 3.4% and {approx}1% for photons and positrons respectively and the expected positron longitudinal polarization is covering a range from 50% to 90%. The full exploitation of the physics potential of an international linear collider (ILC) will require the development of polarized positron beams. Having both e{sup +} and e{sup -} beams polarized will provide new insight into structures of couplings and thus give access to physics beyond the standard model [1]. The concept for a polarized positron source is based on circularly polarized photon sources. These photons are then converted to longitudinally polarized e{sup +} and e{sup -} pairs. While in an experiment at KEK [1a], Compton backscattering is used [2], the E166 experiment uses a helical undulator to produce polarized photons. An undulator-based positron source for the ILC has been proposed in [3,4]. The proposed scheme for an ILC positron source is illustrated in figure 1. In this scheme, a 150 GeV electron beam passes through a 120 m long helical undulator to produce an intense photon beam with a high degree of circular polarization. These photons are converted in a thin target to e{sup +} e{sup -} pairs. The polarized positrons are then collected, pre-accelerated to the damping ring and injected to the main linac. The E166 experiment is

  2. Design, Simulation and Testing of a Precision Alignment Frame for the Next Linear Collider

    SciTech Connect

    Fitsos, P

    2004-06-18

    An alignment frame is developed to support 3 Beam Position Monitors (BPM's) for detecting and ultimately aligning the electron beam from a linear accelerator. This report discusses the design details, preliminary modal analysis of the alignment frame as well as the addition of a metrology frame in the final phase of development.

  3. A Study on Multi-Jets Final States at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Amouzegar, Maya; Halkiadakis, Eva; Lath, Amitabh; Thomas, Scott; Gershtein, Yuri; CMS Collaboration

    2016-03-01

    The LHC (Large Hadron Collider) at CERN, located in Geneva, Switzerland, collides protons at a center of mass energy of 13 TeV. The CMS (Compact Muon Solenoid) detector is one of the four experiments that detects collisions at the LHC. One of the new physics phenomenon that is looked for by the CMS detector is Supersymmetry (SUSY). In our method, we look for these particles by looking at multi-jets final states in interactions that produce up to 8 jets in their final states. By comparing jets in new physics signals with ones produced through QCD, we would be able to predict where new physics might be lying. Since the standard model interactions mostly produce di-jets, if there is an excess of jets at a certain energy, it is possible that a process beyond the standard model is producing those jets. Most of the simulated Monte Carlo signals considered are R-Parity Violating SUSY interactions. In order to perform these studies, we studied the jets' transverse momentum (Pt) divided by the total hadronic energy in the event (HT) as a function of the jet multiplicity, between 2 and 8 jets. If there is an excess of transverse momentum, there is the possibility that SUSY particles are created and are decaying into jets. The studies performed here were a result of the National Science Foundation Research Experiences for Undergraduates (REU) program, and has been supported by funding from NSF Grant PHY-1263280.

  4. Experimental program to build a multimegawatt lasertron for super linear colliders

    SciTech Connect

    Garwin, E.L.; Herrmannsfeldt, W.B.; Sinclair, C.; Weaver, J.N.; Welch, J.J.; Wilson, P.B.

    1985-04-01

    A lasertron (a microwave ''triode'' with an RF output cavity and an RF modulated laser to illuminate a photocathode) is a possible high power RF amplifier for TeV linear colliders. As the first step toward building a 35 MW, S-band lasertron for a proof of principle demonstration, a 400 kV dc diode is being designed with a GaAs photocathode, a drift-tube and a collector. After some cathode life tests are made in the diode, an RF output cavity will replace the drift tube and a mode-locked, frequency-doubled, Nd:YAG laser, modulated to produce a 1 us-long comb of 60 ps pulses at a 2856 MHz rate, will be used to illuminate the photocathode to make an RF power source out of the device. This paper discusses the plans for the project and includes some results of numerical simulation studies of the lasertron as well as some of the ultra-high vacuum and mechanical design requirements for incorporating a photocathode.

  5. A vertically integrated pixel readout device for the Vertex Detector at the International Linear Collider

    SciTech Connect

    Deptuch, Grzegorz; Christian, David; Hoff, James; Lipton, Ronald; Shenai, Alpana; Trimpl, Marcel; Yarema, Raymond; Zimmerman, Tom; /Fermilab

    2008-12-01

    3D-Integrated Circuit technology enables higher densities of electronic circuitry per unit area without the use of nanoscale processes. It is advantageous for mixed mode design with precise analog circuitry because processes with conservative feature sizes typically present lower process dispersions and tolerate higher power supply voltages, resulting in larger separation of a signal from the noise floor. Heterogeneous wafers (different foundries or different process families) may be combined with some 3D integration methods, leading to the optimization of each tier in the 3D stack. Tracking and vertexing in future High-Energy Physics (HEP) experiments involves construction of detectors composed of up to a few billions of channels. Readout electronics must record the position and time of each measurement with the highest achievable precision. This paper reviews a prototype of the first 3D readout chip for HEP, designed for a vertex detector at the International Linear Collider. The prototype features 20 x 20 {micro}m{sup 2} pixels, laid out in an array of 64 x 64 elements and was fabricated in a 3-tier 0.18 {micro}m Fully Depleted SOI CMOS process at MIT-Lincoln Laboratory. The tests showed correct functional operation of the structure. The chip performs a zero-suppressed readout. Successive submissions are planned in a commercial 3D bulk 0.13 {micro}m CMOS process to overcome some of the disadvantages of an FDSOI process.

  6. Cryogenic system configuration for the International Linear Collider (ILC) at mountainous site

    NASA Astrophysics Data System (ADS)

    Nakai, H.; Okamura, T.; Delikaris, D.; Peterson, T.; Yamamoto, A.

    2017-02-01

    The International Linear Collider (ILC) plans to make use of ten cryoplants for its main linacs, each providing 19 kW at 4.5 K equivalent and among of it 3.6 kW at 2 K. Each cryoplant will consist of various cryogenic components such as a 4.5 K refrigerator cold box, a 2 K refrigerator cold box, and helium compressors and so on. In the technical design report (TDR) of the ILC, due to the mountainous topology, almost all cryogenic components would be installed in underground cryogenic caverns next to the main linac tunnels and only cooling towers on surface area. However, we would like to find a more effective and sophisticated configuration of the cryoplant components (cryogenic configuration). Under several constraints of technical, geographical, and environmental points of view, the cryogenic configuration should be considered carefully to satisfy such various conditions. After discussions on this topic conducted at various workshops and conferences, an updated cryogenic configuration is suggested. The proposed updated configuration may affect the total construction cost of the ILC and the entire structure of the ILC conventional facilities. The updated cryogenic configuration is presented and the on-going discussions with the conventional facilities and siting (CFS) colleagues for further improvement of the cryogenic configuration is introduced.

  7. Probing triple Higgs couplings of the two Higgs doublet model at a linear collider

    SciTech Connect

    Arhrib, Abdesslam; Benbrik, Rachid; Chiang, C.-W.

    2008-06-01

    We study double Higgs production at the future linear collider in the framework of the two Higgs doublet models through the following channels: e{sup +}e{sup -}{yields}{phi}{sub i}{phi}{sub j}Z, {phi}{sub i}=h{sup 0}, H{sup 0}, A{sup 0}, H{sup {+-}}. All these processes are sensitive to triple Higgs couplings. Hence observations of them provide information on the triple Higgs couplings that help reconstructing the scalar potential. We also discuss the double Higgs-Strahlung e{sup +}e{sup -}{yields}h{sup 0}h{sup 0}Z in the decoupling limit where h{sup 0} mimics the standard model Higgs boson. The processes e{sup +}e{sup -}{yields}h{sup 0}h{sup 0}Z and e{sup +}e{sup -}{yields}h{sup 0}H{sup 0}Z are also discussed in the fermiophobic limit where distinctive signatures such as 4{gamma}+X, 2{gamma}+X, and 6{gamma}+X are expected in the Type-I two Higgs doublet model.

  8. Radiation and Thermal Analysis of Superconducting Quadrupoles in the Interaction Region of Linear Collider

    SciTech Connect

    Drozhdin, A.I.; Kashikhin, V.V.; Kashikhin, V.S.; Lopes, M.L.; Mokhov, N.V.; Zlobin, A.V.; Seryi, Andrei; /SLAC

    2011-10-14

    Radiation heat deposition in the superconducting magnets of the Interaction Region (IR) of a linear collider can be a serious issue that limits the magnet operating margins and shortens the material lifetime. Radiation and thermal analyses of the IR quadrupoles in the incoming and extraction beam lines of the ILC are performed in order to determine the magnet limits. This paper presents an analysis of the radial, azimuthal and longitudinal distributions of heat deposition in the incoming and disrupted beam doublets. Operation margins of the magnets based on NbTi superconductor are calculated and compared. The radiation and thermal analysis of the ILC IR quadrupoles based on Rutherford type cables was performed. It was found that the peak radiation heat deposition takes place in the second extraction quadrupole QFEX2. The maximum power density in the coil is {approx}17mW/g. This is rather high, comparing to the proton machines (LHC). However, the fast radial decay of the heat deposition together with the high thermal conductivity of the Rutherford type cable limits the coil temperatures to a moderate level. It was determined that both 2-layer and 4-layer QFEX2 magnet designs have thermal margins of a factor of {approx}4 at the nominal gradient of 31.3 T/m. Because of the large margins, these magnets can easily accommodate possible changes in the IR optics and heat deposition levels.

  9. On-line dispersion estimation and correction scheme for the Compact Linear Collider

    NASA Astrophysics Data System (ADS)

    Pfingstner, J.; Adli, E.; Schulte, D.

    2017-01-01

    The Compact Linear Collider (CLIC) has stringent component alignment tolerances in order to preserve the ultralow emittance of the utilized particle beams. Beam-based alignment techniques have been designed to relax these tolerances to realizable values. In this paper, a scheme is presented that is capable of mitigating besides the effects of static misalignments also dynamic misalignments caused by ground motion. It is based on the well-known dispersion-free steering (DFS) algorithm, with the peculiarity that it can perform its correction during the usual operation (on-line). This is enabled by performing the necessary dispersion measurements by introducing only negligibly small beam energy changes (per mille level). It has been found that this on-line correction becomes sensitive to the imperfections of transverse wakefields and structure tilts. These sensitivities have been studied via analytical models and in simulations and appropriate countermeasures to improve the robustness of the method have been proposed. The correction performance and robustness properties of the improved algorithm have been studied in detail with respect to all relevant static and dynamic imperfections in a realistic scenario. The presented scheme is not only a potentially important operational tool for CLIC, but the findings with respect to robustness properties for different imperfections are of general interest for the application of the dispersion-free steering algorithm.

  10. Damped accelerator structures for future linear e/sup/plus minus// colliders

    SciTech Connect

    Deruyter, H.; Hoag, H.A.; Lisin, A.V.; Loew, G.A.; Palmer, R.B.; Paterson, J.M.; Rago, C.E.; Wang, J.W.

    1989-03-01

    This paper describes preliminary work on accelerator structures for future TeV linear colliders which use trains of e/sup +-/ bunches to reach the required luminosity. These bunch trains, if not perfectly aligned with respect to the accelerator axis, induce transverse wake field modes into the structure. Unless they are sufficiently damped, these modes cause cummulative beam deflections and emittance growth. The envisaged structures, originally proposed by R. B. Palmer, are disk-loaded waveguides in which the disks are slotted radially into quadrants. Wake field energy is coupled via the slots and double-ridged waveguides into a lossy region which is external to the accelerator structure. The requirement is that the Q of the HEM/sub 11/ mode be reduced to a value of less than 30. The work done so far includes MAFIA code computations and low power rf measurements to study the fields. A four-cavity 2..pi../3 mode standing-wave structure has been built to find whether the slots lower the electric breakdown thresholds below those reached with conventional disk-loaded structures. We set out to assess the microwave properties of the structure and the problems which might be encountered in fabricating it. 4 refs., 7 figs.

  11. An Automated Magnet Positioning System For Use in the Next Linear Collider

    SciTech Connect

    Viola, Robert J

    2006-02-21

    The Next Linear Collider (NLC) is conceived as the world's most powerful electron-positron particle accelerator. Throughout the NLC, the beam itself will be used to measure errors in the positions of the lattice elements. This beam-based alignment strategy is an essential element of the NLC's design and precision adjustment systems have been identified as a critical enabling technology. Square One proposes a new type of precision manipulator that could be adapted for applications throughout the accelerator. As envisioned, this Tri-Sphere Adjustment System will possess up to six, non-redundant degrees of freedom, be capable of sub-micron resolutions and have ultimate load capacities in excess of 10,000 kg. The system will accommodate thermal expansions and contractions of the objects being supported and can be either motorized or manually actuated. Phase I development tasks will include detailed manipulator design, solution of the associated kinematic equations of motion and evaluation of actuators, gear reducers and transmission systems. The Phase I effort will culminate in the fabrication and full evaluation of a system prototype. A successfully developed Tri-Sphere manipulator could also be used to actively position critical fusion optics, adjust communication dishes or perform parts handling tasks in harsh manufacturing environments.

  12. Current Status of the Next Linear Collider X-Band Klystron Development Program

    SciTech Connect

    Caryotakis, G.; Haase, A.A.; Jongewaard, E.N.; Pearson, C.; Sprehn, D.W.; /SLAC

    2005-05-09

    Klystrons capable of driving accelerator sections in the Next Linear Collider (NLC) have been developed at SLAC during the last decade. In addition to fourteen 50 MW solenoid-focused devices and a 50 MW Periodic Permanent Magnet focused (PPM) klystron, a 500 kV 75 MW PPM klystron was tested in 1999 to 80 MW with 3 {micro}s pulses, but very low duty. Subsequent 75 MW prototypes aimed for low-cost manufacture by employing reusable focusing structures external to the vacuum, similar to a solenoid electromagnet. During the PPM klystron development, several partners (CPI, EEV and Toshiba) have participated by constructing partial or complete PPM klystrons. After early failures during testing of the first two devices, SLAC has recently tested this design (XP3-3) to the full NLC specifications of 75 MW, 1.6 {micro}s pulse length, and 120 Hz. This 14.4 kW average power operation came with an efficiency of 50%. The XP3-3 average and peak output power, together with the focusing method, arguably makes it the most advanced high power klystron ever built anywhere in the world. Design considerations and test results for these latest prototypes will be presented.

  13. Final Cooling for a High-Energy High-Luminosity Lepton Collider

    SciTech Connect

    Neuffer, David; Sayed, H.; Hart, T.; Summers, D.

    2015-12-03

    A high-energy muon collider scenario require a “final cooling” system that reduces transverse emittance by a factor of ~10 while allowing longitudinal emittance increase. The baseline approach has low-energy transverse cooling within high-field solenoids, with strong longitudinal heating. This approach and its recent simulation are discussed. Alternative approaches which more explicitly include emittance exchange are also presented. Round-to-flat beam transform, transverse slicing, and longitudinal bunch coalescence are possible components of an alternative approach. Wedge-based emittance exchange could provide much of the required transverse cooling with longitudinal heating. Li-lens and quadrupole focusing systems could also provide much of the required final cooling.

  14. Analytical approach to chromatic correction in the final focus system of circular colliders

    NASA Astrophysics Data System (ADS)

    Cai, Yunhai

    2016-11-01

    A conventional final focus system in particle accelerators is systematically analyzed. We find simple relations between the parameters of two focus modules in the final telescope. Using the relations, we derive the chromatic Courant-Snyder parameters for the telescope. The parameters are scaled approximately according to (L*/βy*)δ , where L* is the distance from the interaction point to the first quadrupole, βy* the vertical beta function at the interaction point, and δ the relative momentum deviation. Most importantly, we show how to compensate its chromaticity order by order in δ by a traditional correction module flanked by an asymmetric pair of harmonic multipoles. The method enables a circular Higgs collider with 2% momentum aperture and illuminates a path forward to 4% in the future.

  15. Nanosecond-Timescale Intra-Bunch-Train Feedback for the Linear Collider: Results of the FONT2 Run

    SciTech Connect

    Barlow, R.; Dufau, M.; Kalinin, A.; Myatt, G.; Perry, C.; Burrows, P.N.; Hartin, T.; Hussain, S.M.; Molloy, S.; White, G.R.; Adolphsen, C.; Frisch, J.C.; Hendrickson, L.; Jobe, R.K.; Markiewicz, T.; McCormick, D.J.; Nelson, J.; Ross, M.C.; Smith, S.; Smith, T.J.; /SLAC

    2005-05-11

    We report on experimental results from the December 2003/January 2004 data run of the Feedback On Nanosecond Timescales (FONT) experiment at the Next Linear Collider Test Accelerator at SLAC. We built a second-generation prototype intra-train beam-based feedback system incorporating beam position monitors, fast analogue signal processors, a feedback circuit, fast-risetime amplifiers and stripline kickers. We applied a novel real-time charge-normalization scheme to account for beam current variations along the train. We used the system to correct the position of the 170-nanosecond-long bunchtrain at NLCTA. We achieved a latency of 53 nanoseconds, representing a significant improvement on FONT1 (2002), and providing a demonstration of intra-train feedback for the Linear Collider.

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

    ScienceCinema

    None

    2016-07-12

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

  17. Precision Studies of Hadronic and Electro-Weak Interactions for Collider Physics. Final Report

    SciTech Connect

    Yost, Scott A

    2014-04-02

    This project was directed toward developing precision computational tools for proton collisions at the Large Hadron Collider, focusing primarily on electroweak boson production and electroweak radiative corrections. The programs developed under this project carried the name HERWIRI, for High Energy Radiation With Infra-Red Improvements, and are the first steps in an ongoing program to develop a set of hadronic event generators based on combined QCD and QED exponentiation. HERWIRI1 applied these improvements to the hadronic shower, while HERWIRI2 will apply the electroweak corrections from the program KKMC developed for electron-positron scattering to a hadronic event generator, including exponentiated initial and final state radiation together with first-order electroweak corrections to the hard process. Some progress was also made on developing differential reduction techniques for hypergeometric functions, for application to the computation of Feynman diagrams.

  18. The Silicon Detector (SiD) And Linear Collider Detector R&D in Asia And North America

    SciTech Connect

    Brau, J.E.; Breidenbach, M.; Fujii, Y.; /KEK, Tsukuba

    2005-08-11

    In Asia and North America research and development on a linear collider detector has followed complementary paths to that in Europe. Among the developments in the US has been the conception of a detector built around silicon tracking, which relies heavily on a pixel (CCD) vertex detector, and employs a silicon tungsten calorimeter. Since this detector is quite different from the TESLA detector, we describe it here, along with some of the sub-system specific R&D in these regions.

  19. Studies of strong electroweak symmetry breaking at future e{sup +}e{sup {minus}} linear colliders

    SciTech Connect

    Barklow, T.L.

    1994-08-01

    Methods of studying strong electroweak symmetry breaking at future e{sup +}e{sup {minus}} linear colliders are reviewed. Specifically, we review precision measurements of triple gauge boson vertex parameters and the rescattering of longitudinal W bosons in the process e{sup +}e{sup {minus}} {yields} W{sup +}W{sup {minus}}. Quantitative estimates of the sensitivity of each technique to strong electroweak symmetry breaking are included.

  20. Laboratory Frame Analysis of e+e-→μ+μ- Scattering in the Noncommutative Standard Model at Linear Collider

    NASA Astrophysics Data System (ADS)

    Das, Prasanta Kumar; Prakash, Abhishodh

    2012-09-01

    We study the muon pair production e+e-→μ+μ- in the framework of the nonminimal noncommutative standard model (NCSM) to the second-order of the noncommutative (NC) parameter Θμν at linear collider. The {O}(Θ 2) momentum-dependent NC interaction significantly modifies the cross-section and angular distributions which are different from the standard model. After including the effects of earth's rotation we analyze the time-averaged and time-dependent observables in detail. The time-averaged azimuthal distribution of the cross-section shows significant departure from the standard model which can be tested at the upcoming linear collider. We find strong dependence of total cross-section (time-averaged) and their distributions on the orientation and the magnitude of the NC electric vector (ΘE). Assuming that the future linear collider data will differ from the standard model result by 5%, we obtain Λ≥615 GeV and Λ≥946 GeV corresponding to the machine energy Ecom = 1000 GeV and 1500 GeV.

  1. Future e/sup +/e/sup -/ linear colliders and beam-beam effects

    SciTech Connect

    Wilson, P.B.

    1986-05-01

    Numerous concepts, ranging from conventional to highly exotic, hae been proposed for the acceleration of electrons and positrons to very high energies. For any such concept to be viable, it must be possible to produce from it a set of consistent parameters for one of these ''benchmark'' machines. Attention is directed to the choice of parameters for a collider in the 300 GeV energy range, operating at a gradient on the order of 200 MV/m, using X-band power sources to drive a conventional disk-loaded accelerating structure. These rf power sources, while not completely conventional represent a reasonable extrapolation from present technology. The choice of linac parameters is strongly coupled to various beam-beam effects which take place when the electron and positron bunches collide. We summarize these beam-beam effects, and then return to the rf design of a 650 GeV center-of-mass collider. 14 refs.

  2. The Next Linear Collider Test Accelerator's RF Pulse Compression And Transmission

    SciTech Connect

    Tantawi, S.G.; Adelphson, C.; Holmes, S.; Lavine, Theodore L.; Loewen, R.J.; Nantista, C.; Pearson, C.; Pope, R.; Rifkin, J.; Ruth, R.D.; Vlieks, A.E.; /SLAC

    2011-09-14

    The overmoded rf transmission and pulsed power compression system for SLAC's Next Linear Collider (NLC) program requires a high degree of transmission efficiency and mode purity to be economically feasible. To this end, a number of new, high power components and systems have been developed at X-band, which transmit rf power in the low loss, circular TE01 mode with negligible mode conversion. In addition, a highly efficient SLED-II* pulse compressor has been developed and successfully tested at high power. The system produced a 200 MW, 250 ns wide pulse with a near-perfect flat-top. In this paper we describe the design and test results of the high power pulse compression system using SLED-II. The NLC rf systems use low loss highly over-moded circular waveguides operating in the TE01 mode. The efficiency of the systems is sensitive to the mode purity of the mode excited inside these guides. We used the so called flower petal mode transducer [2] to excite the TE01 mode. This type of mode transducer is efficient, compact and capable of handling high levels of power. To make more efficient systems, we modified this device by adding several mode selective chokes to act as mode purifiers. To manipulate the rf signals we used these modified mode converters to convert back and forth between over-moded circular waveguides and single-moded WR90 rectangular waveguides. Then, we used the relatively simple rectangular waveguide components to do the actual manipulation of rf signals. For example, two mode transducers and a mitered rectangular waveguide bend comprise a 90 degree bend. Also, a magic tee and four mode transducers would comprise a four-port-hybrid, etc. We will discuss the efficiency of an rf transport system based on the above methodology. We also used this methodology in building the SLEDII pulse compression system. At SLAC we built 4 of these pulse systems. In this paper we describe the SLEDII system and compare the performance of these 4 systems at SLAC. We

  3. Linear motor free piston compressor. Final report

    SciTech Connect

    Bloomfield, D.P.

    1995-02-17

    A Linear Motor Free Piston Compressor (LMFPC), a free piston pressure recovery system for fuel cell powerplants was developed. The LMFPC consists of a reciprocating compressor and a reciprocating expander which are separated by a piston. In the past energy efficient turbochargers have been used for pressure large (over 50 kW) fuel cell powerplants by recovering pressure energy from the powerplant exhaust. A free piston compressor allows pressurizing 3 - 5 kW sized fuel cell powerplants. The motivation for pressurizing PEM fuel cell powerplants is to improve fuel cell performance. Pressurization of direct methanol fuel cells will IC required if PEM membranes are to be used. Direct methanol oxidation anode catalysts require high temperatures to operate at reasonable power densities. The elevated temperatures above 80 deg C will cause high water loss from conventional PEM membranes unless pressurization is employed. Because pressurization is an energy intensive process, recovery of the pressure energy is required to permit high efficiency in fuel cell powerplants. A complete LMFPC which can pressurize a 3 kW fuel cell stack was built. This unit is one of several that were constructed during the course of the program.

  4. Magnicon development to power TeV colliders. Final report, 16 May 1991--14 May 1994

    SciTech Connect

    Gold, S.H.; Manheimer, W.M.; Fliflet, A.

    1997-04-01

    The goal of this program was the development of a high power frequency-doubling magnicon amplifier at 11.4 GHz. The magnicon is an advanced {open_quotes}scanning-beam{close_quotes} microwave amplifier tube for use in powering future high gradient linear accelerators, such as the proposed TeV linear collider known as the Next Linear Collider (NLC). The rf source for the NLC must provide a power of 500 MW to 1 GW per tube in a 200 nsec pulse at a frequency in the range of 10-20 GHz. The required power can either be generated directly in 200 nsec pulses, or generated at longer pulse lengths (e.g., 1-2 {mu}sec) and then pulse-compressed. Because the average power required by the NLC is so large, source efficiency is a crucial consideration.

  5. Comment on ``Beamstrahlung considerations in laser-plasma-accelerator-based linear colliders''

    NASA Astrophysics Data System (ADS)

    Lebedev, Valeri; Nagaitsev, Sergei

    2013-10-01

    Schroeder, Esarey, Geddes, Benedetti, and Leemans [Phys. Rev. ST Accel. Beams 13, 101301 (2010)PRABFM1098-440210.1103/PhysRevSTAB.13.101301 and Phys. Rev. ST Accel. Beams 15, 051301 (2012)PRABFM1098-440210.1103/PhysRevSTAB.15.051301] have proposed a set of parameters for a TeV-scale collider based on plasma wakefield accelerator principles. In particular, it is sugested that the luminosities greater than 1034cm-2s-1 are attainable for an electron-positron collider. In this Comment we dispute this set of parameters on the basis of first principles. The interactions of accelerating beam with plasma impose fundamental limitations on beam properties and, thus, on attainable luminosity values.

  6. 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

  7. Single production of excited spin-3/2 neutrinos at linear colliders

    SciTech Connect

    Cakir, O.; Ozansoy, A.

    2009-03-01

    We study the potential of future high energy e{sup +}e{sup -} colliders to probe excited neutrino signals in different channels coming from the single production process via gauge interactions. We calculate the production cross section, decay widths, and branching ratios of excited spin-3/2 neutrinos according to their effective currents and we compare them with those of the spin-1/2 ones. The signals and corresponding backgrounds are examined in detail to get accessible limits on the masses and couplings of excited spin-3/2 neutrinos.

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

    SciTech Connect

    Assmann, R

    2004-06-08

    The feasibility of future linear colliders depends on achieving very tight alignment and steering tolerances. All proposals (NLC, JLC, CLIC, TESLA and S-BAND) currently require a total emittance growth in the main linac of less than 30-100% [1]. This should be compared with a 100% emittance growth in the much smaller SLC linac [2]. Major advances in alignment and beam steering techniques beyond those used in the SLC are necessary for the next generation of linear colliders. In this paper, we present an experimental study of quadrupole alignment with a dispersion-free steering algorithm. A closely related method (wakefield-free steering) takes into account wakefield effects [3]. However, this method can not be studied at the SLC. The requirements for future linear colliders lead to new and unconventional ideas about alignment and beam steering. For example, no dipole correctors are foreseen for the standard trajectory correction in the NLC [4]; beam steering will be done by moving the quadrupole positions with magnet movers. This illustrates the close symbiosis between alignment, beam steering and beam dynamics that will emerge. It is no longer possible to consider the accelerator alignment as static with only a few surveys and realignments per year. The alignment in future linear colliders will be a dynamic process in which the whole linac, with thousands of beam-line elements, is aligned in a few hours or minutes, while the required accuracy of about 5 pm for the NLC quadrupole alignment [4] is a factor of 20 higher than in existing accelerators. The major task in alignment and steering is the accurate determination of the optimum beam-line position. Ideally one would like all elements to be aligned along a straight line. However, this is not practical. Instead a ''smooth curve'' is acceptable as long as its wavelength is much longer than the betatron wavelength of the accelerated beam. Conventional alignment methods are limited in accuracy by errors in the survey

  9. Discriminating between Z Prime -boson effects and effects of anomalous gauge couplings in the double production of W{sup {+-}} bosons at a linear collider

    SciTech Connect

    Andreev, Vasili V.; Pankov, A. A.

    2013-06-15

    The potential of the International Linear electron-positron Collider (ILC) for seeking, in the annihilation production of W{sup {+-}}-boson pairs, signals induced by new neutral gauge bosons predicted by models belonging to various classes and featuring an extended gauge sector is studied. Limits that will be obtained at ILC for the parameters and masses of Z Prime bosons are compared with present-day and future data from the Large Hadron Collider (LHC). The possibility of discriminating between the effects of Z-Z Prime mixing and signals induced by anomalous gauge couplings (AGC) is demonstrated within theoretically motivated trilinear gauge models involving several free anomalous parameters. It is found that the sensitivity of ILC to the effects of Z-Z Prime mixing in the process e{sup +}e{sup -} {yields} W{sup +}W{sup -} and its ability to discriminate between these two new-physics scenarios, Z Prime and AGC, become substantially higher upon employing polarized initial (e{sup +}e{sup -}) and final (W{sup {+-}}) states.

  10. International Linear Collider Reference Design Report Volume 2: Physics at the ILC

    SciTech Connect

    Aarons, Gerald; Abe, Toshinori; Abernathy, Jason; Ablikim, Medina; Abramowicz, Halina; Adey, David; Adloff, Catherine; Adolphsen, Chris; Afanaciev, Konstantin; Agapov, Ilya; Ahn, Jung-Keun; Aihara, Hiroaki; Akemoto, Mitsuo; del Carmen Alabau, Maria; Albert, Justin; Albrecht, Hartwig; Albrecht, Michael; Alesini, David; Alexander, Gideon; Alexander, Jim; Allison, Wade; /SLAC /Tokyo U. /Victoria U. /Beijing, Inst. High Energy Phys. /Tel Aviv U. /Birmingham U. /Annecy, LAPP /Minsk, High Energy Phys. Ctr. /DESY /Royal Holloway, U. of London /CERN /Pusan Natl. U. /KEK, Tsukuba /Orsay, LAL /Notre Dame U. /Frascati /Cornell U., Phys. Dept. /Oxford U. /Hefei, CUST /Bangalore, Indian Inst. Sci. /Fermilab

    2011-11-14

    The triumph of 20th century particle physics was the development of the Standard Model and the confirmation of many of its aspects. Experiments determined the particle constituents of ordinary matter, and identified four forces that hold matter together and transform it from one form to another. Particle interactions were found to obey precise laws of relativity and quantum theory. Remarkable features of quantum physics were observed, including the real effects of 'virtual' particles on the visible world. Building on this success, particle physicists are now able to address questions that are even more fundamental, and explore some of the deepest mysteries in science. The scope of these questions is illustrated by this summary from the report Quantum Universe: (1) Are there undiscovered principles of nature; (2) How can we solve the mystery of dark energy; (3) Are there extra dimensions of space; (4) Do all the forces become one; (5) Why are there so many particles; (6) What is dark matter? How can we make it in the laboratory; (7) What are neutrinos telling us; (8) How did the universe begin; and (9) What happened to the antimatter? A worldwide program of particle physics investigations, using multiple approaches, is already underway to explore this compelling scientific landscape. As emphasized in many scientific studies, the International Linear Collider is expected to play a central role in what is likely to be an era of revolutionary advances. Discoveries from the ILC could have breakthrough impact on many of these fundamental questions. Many of the scientific opportunities for the ILC involve the Higgs particle and related new phenomena at Terascale energies. The Standard Model boldly hypothesizes a new form of Terascale energy, called the Higgs field, that permeates the entire universe. Elementary particles acquire mass by interacting with this field. The Higgs field also breaks a fundamental electroweak force into two forces, the electromagnetic and weak

  11. A method for the precision mass measurement of the stop quark at the International Linear Collider

    NASA Astrophysics Data System (ADS)

    Freitas, Ayres; Milsténe, Caroline; Schmitt, Michael; Sopczak, Andre

    2008-09-01

    Many supersymmetric models predict new particles within the reach of the next generation of colliders. For an understanding of the model structure and the mechanism(s) of symmetry breaking, it is important to know the masses of the new particles precisely. In this article the measurement of the mass of the scalar partner of the top quark (stop) at an e+e- collider is studied. A relatively light stop is motivated by attempts to explain electroweak baryogenesis and can play an important role in dark matter relic density. A method is presented which makes use of cross-section measurements near the pair-production threshold as well as at higher center-of-mass energies. It is shown that this method not only increases the statistical precision, but also greatly reduces the systematic uncertainties, which can be important. Numerical results are presented, based on a realistic event simulation, for two signal selection strategies: using conventional selection cuts, and using an Iterative Discriminant Analysis (IDA). Our studies indicate that a precision of Δmtilde t1 = 0.42 GeV can be achieved, representing a major improvement over previous studies. While the analysis of stops is particularly challenging due to the possibility of stop hadronization, the general procedure could be applied to the mass measurement of other particles as well. We also comment on the potential of the IDA to discover a stop quark in this scenario, and we revisit the accuracy of the theoretical predictions for the neutralino relic density.

  12. Update on the high-current injector for the Stanford Linear collider

    SciTech Connect

    James, M.B.; Clendenin, J.E.; Ecklund, S.D.; Miller, R.H.; Sheppard, J.C.; Sinclair, C.K.; Sodja, J.

    1983-03-01

    The high current injector has become operational. There are two crucial areas where improvements must be made to meet collider specifications: while the injector can produce up to 10/sup 11/ e/sup -/ in a single S-band bucket, initially much of this charge was captured in a low energy tail and was this not suitable for transport through the accelerator and injection into the damping ring. Pulse to pulse position jitter has been observed, resulting in transverse wake field which increases beam emittance. The problems described above contribute to substantial current loss during transport from the injector (40 MeV) to the SLC damping ring (1.2 GeV). Experimental studies are continuing with the aim of understanding and improving beam characteristics including bunch length, pulse to pulse stability and emittance. The present status of these studies is reported.

  13. A Method for the Precision Mass Measurement of the Stop Quark at the International Linear Collider

    SciTech Connect

    Freitas, Ayres; Milstene, Caroline; Schmitt, Michael; Sopczak, Andre; /Lancaster U.

    2007-12-01

    Many supersymmetric models predict new particles within the reach of the next generation of colliders. For an understanding of the model structure and the mechanism(s) of symmetry breaking, it is important to know the masses of the new particles precisely. In this article the measurement of the mass of the scalar partner of the top quark (stop) at an e{sup +}e{sup -} collider is studied. A relatively light stop is motivated by attempts to explain electroweak baryogenesis and can play an important role in dark matter relic density. A method is presented which makes use of cross-section measurements near the pair-production threshold as well as at higher center-of-mass energies. It is shown that this method not only increases the statistical precision, but also greatly reduces the systematic uncertainties, which can be important. numerical results are presented, based on a realistic event simulation, for two signal selection strategies: using conventional selection cuts, and using an Iterative Discriminant Analysis (IDA). The studies indicate that a precision of {Delta}m{sub {bar t}{sub 1}} = 0.42 GeV can be achieved, representing a major improvement over previous studies. While the analysis of stops is particularly challenging due to the possibility of stop hadronization, the general procedure could be applied to the mass measurement of other particles as well. They also comment on the potential of the IDA to discover a stop quark in this scenario, and they revisit the accuracy of the theoretical predictions for the neutralino relic density.

  14. Final Report - The Decline and Fall of the Superconducting Super Collider

    SciTech Connect

    RIORDAN, MICHAEL

    2011-11-29

    In October 1993 the US Congress terminated the Superconducting Super Collider — at the time the largest pure-science project ever attempted, with a total cost estimated to exceed $10 billion. It was a stunning loss for the US highenergy physics community, which until that moment had perched for decades at the pinnacle of American science. Ever since 1993, this once-dominant scientific community has been in gradual decline. With the 2010 startup of research on the CERN Large Hadron Collider and the 2011 shutdown of the Fermilab Tevatron, world leadership in elementary-particle physics has crossed the Atlantic and returned to Europe.

  15. Recent Electron-Cloud Simulation Results for the Main Damping Rings of the NLC and the TESLA Linear Colliders

    SciTech Connect

    Pivi, Mauro T F

    2003-05-19

    In the beam pipe of the Main Damping Ring (MDR) of the Next Linear Collider (NLC), ionization of residual gases and secondary emission give rise to an electron-cloud which stabilizes to equilibrium after few bunch trains. In this paper, we present recent computer simulation results for the main features of the electron cloud at the NLC and preliminary simulation results for the TESLA main damping rings, obtained with the code POSINST that has been developed at LBNL, and lately in collaboration with SLAC, over the past 7 years. Possible remedies to mitigate the effect are also discussed. We have recently included the possibility to simulate different magnetic field configurations in our code including solenoid, quadrupole, sextupole and wiggler.

  16. Recent electron-cloud simulation results for the main damping rings of the NLC and TESLA linear colliders

    SciTech Connect

    Pivi, M.; Raubenheimer, T.O.; Furman, M.A.

    2003-05-01

    In the beam pipe of the Main Damping Ring (MDR) of the Next Linear Collider (NLC), ionization of residual gases and secondary emission give rise to an electron-cloud which stabilizes to equilibrium after few bunch trains. In this paper, we present recent computer simulation results for the main features of the electron cloud at the NLC and preliminary simulation results for the TESLA main damping rings, obtained with the code POSINST that has been developed at LBNL, and lately in collaboration with SLAC, over the past 7 years. Possible remedies to mitigate the effect are also discussed. We have recently included the possibility to simulate different magnetic field configurations in our code including solenoid, quadrupole, sextupole and wiggler.

  17. 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.

  18. 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.

  19. Rollfix---An adiabatic roll transition for the SLC (Stanford Linear Collider) Arcs

    SciTech Connect

    Bambade, P.; Brown, K.; Fieguth, T.; Hutton, A.; Ritson, D.; Sands, M.; Toge, N.

    1989-02-01

    The SLC Arcs were rolled at achromat boundaries to follow the terrain of the SLAC site. This makes the linear optics sensitive to systematic gradient errors, from which severe cross-plane coupling effects may arise. As a partial correction, a smoother roll transition was introduced which relieves much of this sensitivity. We present an evaluation of this scheme and report on the observed improvements. 18 refs., 10 figs.

  20. Exclusive vector meson photoproduction at the LHC and a future circular collider: A closer look on the final state

    NASA Astrophysics Data System (ADS)

    da Silveira, G. Gil; Gonçalves, V. P.; Jaime, M. M.

    2017-02-01

    Over the past years, the LHC experiments have reported experimental evidence for processes associated to photon-photon and photon-hadron interactions, showing their potential to investigate the production of low- and high-mass systems in exclusive events. In the particular case of the photoproduction of vector mesons, the experimental study of this final state is expected to shed light on the description of the QCD dynamics at small values of the Bjorken-x variable. In this paper, we extend previous studies for the exclusive J /Ψ and ϒ photoproduction in p p collisions based on the nonlinear QCD dynamics by performing a detailed study of the final-state distributions that can be measured experimentally at the LHC and at a future circular collider. Predictions for the rapidity and transverse momentum distributions of the vector mesons and of final-state dimuons are presented for p p collisions at √{s }=7 , 13, and 100 TeV.

  1. Synchrotron radiation and absence of linear polarization in the colliding wind binary WR 146

    NASA Astrophysics Data System (ADS)

    Hales, C. A.; Benaglia, P.; del Palacio, S.; Romero, G. E.; Koribalski, B. S.

    2017-01-01

    Context. Several massive early-type binaries exhibit non-thermal emission which has been attributed to synchrotron radiation from particles accelerated by diffusive shock acceleration (DSA) in the wind-collision region (WCR). If the magnetic field in the strong shocks is ordered, its component parallel to the shock front should be enhanced, and the resultant synchrotron radiation would be polarized. However, such polarization has never been measured. Aims: We aim to determine the percentage of linearly polarized emission from the well-known non-thermal radio emitter WR 146, a WC6+O8 system. Methods: We performed spatially-unresolved radio continuum observations of WR 146 at 5 cm and 20 cm with the Karl G. Jansky Very Large Array. We constructed a numerical model to investigate a scenario where particles are accelerated by turbulent magnetic reconnection (MR), and we performed a quantitative analysis of possible depolarization effects. Results: No linearly polarized radio emission was detected. The data constrain the fractional linear polarization to less than 0.6% between 1 to 8 GHz. This is compatible with a high level of turbulence and a dominant random component in the magnetic field. In this case the relativistic particles could be produced by turbulent magnetic reconnection. In order for this scenario to satisfy the required non-thermal energy budget, the strength of the magnetic field in the WCR must be as high as 150 mG. However, if the magnetic field is ordered and DSA is ongoing, then a combination of internal and external Faraday rotation could equally account for the depolarization of the emission. Conclusions: The absence of polarization could be caused by a highly turbulent magnetic field, other depolarization mechanisms such as Faraday rotation in the stellar wind, or a combination of these processes. It is not clear whether it is possible to develop the high level of turbulence and strong magnetic fields required for efficient MR in a long

  2. A precise measurement of the left-right asymmetry of Z Boson production at the SLAC linear collider

    SciTech Connect

    1994-09-01

    We present a precise measurement of the left-right cross section asymmetry of Z boson production (A{sub LR}) observed in 1993 data at the SLAC linear collider. The A{sub LR} experiment provides a direct measure of the effective weak mixing angle through the initial state couplings of the electron to the Z. During the 1993 run of the SLC, the SLD detector recorded 49,392 Z events produced by the collision of longitudinally polarized electrons on unpolarized positrons at a center-of-mass energy of 91.26 GeV. A Compton polarimeter measured the luminosity-weighted electron polarization to be (63.4{+-}1.3)%. ALR was measured to be 0.1617{+-}0.0071(stat.){+-}0.0033(syst.), which determines the effective weak mixing angle to be sin {sup 2}{theta}{sub W}{sup eff} = 0.2292{+-}0.0009(stat.){+-}0.0004(syst.). This measurement of A{sub LR} is incompatible at the level of two standard deviations with the value predicted by a fit of several other electroweak measurements to the Standard Model.

  3. The development of an annular-beam, high power free-electron maser for future linear colliders

    SciTech Connect

    Fazio, M.V.; Carlsten, B.E.; Earley, L.M.; Fortgang, C.M.; Haddock, P.C.; Haynes, W.B.

    1996-09-01

    Work is under way to develop a 17 GHz free electron maser (FEM) for producing a 500 MW output pulse with a phase stability appropriate for linear collider applications. We plan to use a 500 keV, 5 kV, 6 cm diameter annular electron beam to excite a TM{sub 02} mode Raman FEM amplifier in a corrugated cylindrical waveguide. The annular beam will run close to the interaction device walls to reduce the power density in the fields, and to greatly reduce the kinetic energy loss caused by beam potential depression associated with the space charge which is a significant advantage in comparison with conventional solid beam microwave tubes at the same beam current. A key advantage of the annular beam is that the reduced plasma wave number can be tuned to achieve phase stability for an arbitrary correlation on interaction strength with beam velocity. It should be noted that this technique for improving phase stability of an EM in not possible with a solid beam klystron. The annular beam FEM provides the opportunity to extend the output power of sources in the 17 GHz regime by well over an order of magnitude with enhanced phase stability. The design and experimental status are discussed.

  4. Implications of the 750 GeV γγ Resonance as a Case Study 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; Poschl, Roman; Reuter, Jurgen; Simon, Frank; Tanabe, Tomohiko; Yu, Jaehoon; Wells, James D.; Falkowski, Adam; Matsumoto, Shigeki; Moroi, Takeo; Richard, Francois; Tian, Junping; Vos, Marcel; Yokoya, Hiroshi; Murayama, Hitoshi; Yamamoto, Hitoshi

    2016-07-14

    If the γγ resonance at 750 GeV suggested by 2015 LHC data turns out to be a real effect, what are the implications for the physics case and upgrade path of the International Linear Collider? Whether or not the resonance is confirmed, this question provides an interesting case study testing the robustness of the ILC physics case. In this note, we address this question with two points: (1) Almost all models proposed for the new 750 GeV particle require additional new particles with electroweak couplings. The key elements of the 500 GeV ILC physics program - precision measurements of the Higgs boson, the top quark, and 4-fermion interactions - will powerfully discriminate among these models. This information will be important in conjunction with new LHC data, or alone, if the new particles accompanying the 750 GeV resonance are beyond the mass reach of the LHC. (2) Over a longer term, the energy upgrade of the ILC to 1 TeV already discussed in the ILC TDR will enable experiments in γγ and e+e- collisions to directly produce and study the 750 GeV particle from these unique initial states.

  5. Discovery potential of Higgs boson pair production through final states at a 100 TeV collider

    NASA Astrophysics Data System (ADS)

    Zhao, Xiaoran; Li, Qiang; Li, Zhao; Yan, Qi-Shu

    2017-02-01

    We explore the discovery potential of Higgs pair production at a 100 TeV collider via full leptonic mode. The same mode can be explored at the LHC when Higgs pair production is enhanced by new physics. We examine two types of fully leptonic final states and propose a partial reconstruction method, which can reconstruct some useful kinematic observables. It is found that the m T2 variable determined by this reconstruction method and the reconstructed visible Higgs mass are crucial to discriminate the signal and background events. It is also noticed that a new variable, denoted as Δm, which is defined as the mass difference of two possible combinations, is very useful as a discriminant. To examine the detector effects, we consider seven detector setups for a 100 TeV collider and investigate the changes in the sensitivity, and we find that lepton isolation and the minimal lepton P t cut are crucial in order to reduce the integrated luminosity. Supported by Natural Science Foundation of China (11175251, 11305179, 11675185, 11475180, 11575005) The work of Q. Li and Q.S. Yan is partially supported by CAS Center for Excellence in Particle Physics (CCEPP), X. Zhao is partially supported by the European Union as part of the FP7 Marie Curie Initial Training Network MCnetITN (PITN-GA-2012-315877).

  6. Design study of beam dynamics issues for 1 TeV next linear collider based upon the relativistic-klystron two-beam accelerator

    SciTech Connect

    Li, H.; Goffeney, N.; Henestroza, E.; Sessler, A.; Yu, S.; Houck, T.; Westenskow, G.

    1994-11-01

    A design study has recently been conducted for exploring the feasibility of a relativistic-klystron two-beam accelerator (RK-TBA) system as a rf power source for a 1 TeV linear collider. The author present, in this paper, the beam dynamics part of this study. They have achieved in their design study acceptable transverse and longitudinal beam stability properties for the resulting high efficiency and low cost RK-TBA.

  7. First observation of vector boson pairs in a hadronic final state at the tevatron collider.

    PubMed

    Aaltonen, T; Adelman, J; Akimoto, T; Alvarez González, B; Amerio, S; Amidei, D; Anastassov, A; Annovi, A; Antos, J; Apollinari, G; Apresyan, A; Arisawa, T; Artikov, A; Ashmanskas, W; Attal, A; Aurisano, A; Azfar, F; Badgett, W; Barbaro-Galtieri, A; Barnes, V E; Barnett, B A; Barria, P; Bartsch, V; Bauer, G; Beauchemin, P-H; Bedeschi, F; Beecher, D; Behari, S; Bellettini, G; Bellinger, J; Benjamin, D; Beretvas, A; Beringer, J; Bhatti, A; Binkley, M; Bisello, D; Bizjak, I; Blair, R E; Blocker, C; Blumenfeld, B; Bocci, A; Bodek, A; Boisvert, V; Bolla, G; Bortoletto, D; Boudreau, J; Boveia, A; Brau, B; Bridgeman, A; Brigliadori, L; Bromberg, C; Brubaker, E; Budagov, J; Budd, H S; Budd, S; Burke, S; Burkett, K; Busetto, G; Bussey, P; Buzatu, A; Byrum, K L; Cabrera, S; Calancha, C; Campanelli, M; Campbell, M; Canelli, F; Canepa, A; Carls, B; Carlsmith, D; Carosi, R; Carrillo, S; Carron, S; Casal, B; Casarsa, M; Castro, A; Catastini, P; Cauz, D; Cavaliere, V; Cavalli-Sforza, M; Cerri, A; Cerrito, L; Chang, S H; Chen, Y C; Chertok, M; Chiarelli, G; Chlachidze, G; Chlebana, F; Cho, K; Chokheli, D; Chou, J P; Choudalakis, G; Chuang, S H; Chung, K; Chung, W H; Chung, Y S; Chwalek, T; Ciobanu, C I; Ciocci, M A; Clark, A; Clark, D; Compostella, G; Convery, M E; Conway, J; Cordelli, M; Cortiana, G; Cox, C A; Cox, D J; Crescioli, F; Almenar, C Cuenca; Cuevas, J; Culbertson, R; Cully, J C; Dagenhart, D; Datta, M; Davies, T; de Barbaro, P; De Cecco, S; Deisher, A; De Lorenzo, G; Dell'Orso, M; Deluca, C; Demortier, L; Deng, J; Deninno, M; Derwent, P F; Di Canto, A; di Giovanni, G P; Dionisi, C; Di Ruzza, B; Dittmann, J R; D'Onofrio, M; Donati, S; Dong, P; Donini, J; Dorigo, T; Dube, S; Efron, J; Elagin, A; Erbacher, R; Errede, D; Errede, S; Eusebi, R; Fang, H C; Farrington, S; Fedorko, W T; Feild, R G; Feindt, M; Fernandez, J P; Ferrazza, C; Field, R; Flanagan, G; Forrest, R; Frank, M J; Franklin, M; Freeman, J C; Furic, I; Gallinaro, M; Galyardt, J; Garberson, F; Garcia, J E; Garfinkel, A F; Garosi, P; Genser, K; Gerberich, H; Gerdes, D; Gessler, A; Giagu, S; Giakoumopoulou, V; Giannetti, P; Gibson, K; Gimmell, J L; Ginsburg, C M; Giokaris, N; Giordani, M; Giromini, P; Giunta, M; Giurgiu, G; Glagolev, V; Glenzinski, D; Gold, M; Goldschmidt, N; Golossanov, A; Gomez, G; Gomez-Ceballos, G; Goncharov, M; González, O; Gorelov, I; Goshaw, A T; Goulianos, K; Gresele, A; Grinstein, S; Grosso-Pilcher, C; Group, R C; Grundler, U; Guimaraes da Costa, J; Gunay-Unalan, Z; Haber, C; Hahn, K; Hahn, S R; Halkiadakis, E; Han, B-Y; Han, J Y; Happacher, F; Hara, K; Hare, D; Hare, M; Harper, S; Harr, R F; Harris, R M; Hartz, M; Hatakeyama, K; Hays, C; Heck, M; Heijboer, A; Heinemann, B; Heinrich, J; Henderson, C; Herndon, M; Heuser, J; Hewamanage, S; Hidas, D; Hill, C S; Hirschbuehl, D; Hocker, A; Hou, S; Houlden, M; Hsu, S-C; Huffman, B T; Hughes, R E; Husemann, U; Hussein, M; Huston, J; Incandela, J; Introzzi, G; Iori, M; Ivanov, A; James, E; Jang, D; Jayatilaka, B; Jeon, E J; Jha, M K; Jindariani, S; Johnson, W; Jones, M; Joo, K K; Jun, S Y; Jung, J E; Junk, T R; Kamon, T; Kar, D; Karchin, P E; Kato, Y; Kephart, R; Ketchum, W; Keung, J; Khotilovich, V; Kilminster, B; Kim, D H; Kim, H S; Kim, H W; Kim, J E; Kim, M J; Kim, S B; Kim, S H; Kim, Y K; Kimura, N; Kirsch, L; Klimenko, S; Knuteson, B; Ko, B R; Kondo, K; Kong, D J; Konigsberg, J; Korytov, A; Kotwal, A V; Kreps, M; Kroll, J; Krop, D; Krumnack, N; Kruse, M; Krutelyov, V; Kubo, T; Kuhr, T; Kulkarni, N P; Kurata, M; Kwang, S; Laasanen, A T; Lami, S; Lammel, S; Lancaster, M; Lander, R L; Lannon, K; Lath, A; Latino, G; Lazzizzera, I; LeCompte, T; Lee, E; Lee, H S; Lee, S W; Leone, S; Lewis, J D; Lin, C-S; Linacre, J; Lindgren, M; Lipeles, E; Lister, A; Litvintsev, D O; Liu, C; Liu, T; Lockyer, N S; Loginov, A; Loreti, M; Lovas, L; Lucchesi, D; Luci, C; Lueck, J; Lujan, P; Lukens, P; Lungu, G; Lyons, L; Lys, J; Lysak, R; MacQueen, D; Madrak, R; Maeshima, K; Makhoul, K; Maki, T; Maksimovic, P; Malde, S; Malik, S; Manca, G; Manousakis-Katsikakis, A; Margaroli, F; Marino, C; Marino, C P; Martin, A; Martin, V; Martínez, M; Martínez-Ballarín, R; Maruyama, T; Mastrandrea, P; Masubuchi, T; Mathis, M; Mattson, M E; Mazzanti, P; McFarland, K S; McIntyre, P; McNulty, R; Mehta, A; Mehtala, P; Menzione, A; Merkel, P; Mesropian, C; Miao, T; Miladinovic, N; Miller, R; Mills, C; Milnik, M; Mitra, A; Mitselmakher, G; Miyake, H; Moggi, N; Mondragon, M N; Moon, C S; Moore, R; Morello, M J; Morlock, J; Fernandez, P Movilla; Mülmenstädt, J; Mukherjee, A; Muller, Th; Mumford, R; Murat, P; Mussini, M; Nachtman, J; Nagai, Y; Nagano, A; Naganoma, J; Nakamura, K; Nakano, I; Napier, A; Necula, V; Nett, J; Neu, C; Neubauer, M S; Neubauer, S; Nielsen, J; Nodulman, L; Norman, M; Norniella, O; Nurse, E; Oakes, L; Oh, S H; Oh, Y D; Oksuzian, I; Okusawa, T; Orava, R; Osterberg, K; Griso, S Pagan; Palencia, E; Papadimitriou, V; Papaikonomou, A; Paramonov, A A; Parks, B; Pashapour, S; Patrick, J; Pauletta, G; Paulini, M; Paus, C; Peiffer, T; Pellett, D E; Penzo, A; Phillips, T J; Piacentino, G; Pianori, E; Pinera, L; Pitts, K; Plager, C; Pondrom, L; Poukhov, O; Pounder, N; Prakoshyn, F; Pronko, A; Proudfoot, J; Ptohos, F; Pueschel, E; Punzi, G; Pursley, J; Rademacker, J; Rahaman, A; Ramakrishnan, V; Ranjan, N; Redondo, I; Renton, P; Renz, M; Rescigno, M; Richter, S; Rimondi, F; Ristori, L; Robson, A; Rodrigo, T; Rodriguez, T; Rogers, E; Rolli, S; Roser, R; Rossi, M; Rossin, R; Roy, P; Ruiz, A; Russ, J; Rusu, V; Rutherford, B; Saarikko, H; Safonov, A; Sakumoto, W K; Saltó, O; Santi, L; Sarkar, S; Sartori, L; Sato, K; Savoy-Navarro, A; Schlabach, P; Schmidt, A; Schmidt, E E; Schmidt, M A; Schmidt, M P; Schmitt, M; Schwarz, T; Scodellaro, L; Scribano, A; Scuri, F; Sedov, A; Seidel, S; Seiya, Y; Semenov, A; Sexton-Kennedy, L; Sforza, F; Sfyrla, A; Shalhout, S Z; Shears, T; Shepard, P F; Shimojima, M; Shiraishi, S; Shochet, M; Shon, Y; Shreyber, I; Sinervo, P; Sisakyan, A; Slaughter, A J; Slaunwhite, J; Sliwa, K; Smith, J R; Snider, F D; Snihur, R; Soha, A; Somalwar, S; Sorin, V; Spreitzer, T; Squillacioti, P; Stanitzki, M; St Denis, R; Stelzer, B; Stelzer-Chilton, O; Stentz, D; Strologas, J; Strycker, G L; Suh, J S; Sukhanov, A; Suslov, I; Suzuki, T; Taffard, A; Takashima, R; Takeuchi, Y; Tanaka, R; Tecchio, M; Teng, P K; Terashi, K; Thom, J; Thompson, A S; Thompson, G A; Thomson, E; Tipton, P; Ttito-Guzmán, P; Tkaczyk, S; Toback, D; Tokar, S; Tollefson, K; Tomura, T; Tonelli, D; Torre, S; Torretta, D; Totaro, P; Tourneur, S; Trovato, M; Tsai, S-Y; Tu, Y; Turini, N; Ukegawa, F; Vallecorsa, S; van Remortel, N; Varganov, A; Vataga, E; Vázquez, F; Velev, G; Vellidis, C; Vidal, M; Vidal, R; Vila, I; Vilar, R; Vine, T; Vogel, M; Volobouev, I; Volpi, G; Wagner, P; Wagner, R G; Wagner, R L; Wagner, W; Wagner-Kuhr, J; Wakisaka, T; Wallny, R; Wang, S M; Warburton, A; Waters, D; Weinberger, M; Weinelt, J; Wester, W C; Whitehouse, B; Whiteson, D; Wicklund, A B; Wicklund, E; Wilbur, S; Williams, G; Williams, H H; Wilson, P; Winer, B L; Wittich, P; Wolbers, S; Wolfe, C; Wright, T; Wu, X; Würthwein, F; Xie, S; Yagil, A; Yamamoto, K; Yamaoka, J; Yang, U K; Yang, Y C; Yao, W M; Yeh, G P; Yi, K; Yoh, J; Yorita, K; Yoshida, T; Yu, G B; Yu, I; Yu, S S; Yun, J C; Zanello, L; Zanetti, A; Zhang, X; Zheng, Y; Zucchelli, S

    2009-08-28

    We present the first observation in hadronic collisions of the electroweak production of vector boson pairs (VV, V = W, Z) where one boson decays to a dijet final state. The data correspond to 3.5 fb(-1) of integrated luminosity of pp[over ] collisions at sqrt[s] = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We observe 1516 + or - 239(stat) + or - 144(syst) diboson candidate events and measure a cross section sigma(pp[over ]-->VV + X) of 18.0 + or - 2.8(stat) + or - 2.4(syst) + or -1.1(lumi) pb, in agreement with the expectations of the standard model.

  8. First Observation of Vector Boson Pairs in a Hadronic Final State at the Tevatron Collider

    SciTech Connect

    Aaltonen, T.; Adelman, Jahred A.; Akimoto, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, Dante E.; Anastassov, A.; Annovi, Alberto; Antos, Jaroslav; Apollinari, G.; Apresyan, A.; /Purdue U. /Waseda U.

    2009-05-01

    We present the first observation in hadronic collisions of the electroweak production of vector boson pairs (VV, V = W,Z) where one boson decays to a dijet final state. The data correspond to 3.5 fb{sup -1} of integrated luminosity of p{bar p} collisions at {radical}s = 1.96 TeV collected by the CDF II detector at the Fermilab Tevatron. We observe 1516 {+-} 239(stat) {+-} 144(syst) diboson candidate events and measure a cross section {sigma}(p{bar p} {yields} VV + X) of 18.0 {+-} 2.8(stat) {+-} 2.4(syst) {+-} 1.1(lumi) pb, in agreement with the expectations of the standard model.

  9. First Observation of Vector Boson Pairs in a Hadronic Final State at the Tevatron Collider

    NASA Astrophysics Data System (ADS)

    Aaltonen, T.; Adelman, J.; Akimoto, T.; Álvarez González, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Apresyan, A.; Arisawa, T.; Artikov, A.; Ashmanskas, W.; Attal, A.; Aurisano, A.; Azfar, F.; Badgett, W.; Barbaro-Galtieri, A.; Barnes, V. E.; Barnett, B. A.; Barria, P.; Bartsch, V.; Bauer, G.; Beauchemin, P.-H.; Bedeschi, F.; Beecher, D.; Behari, S.; Bellettini, G.; Bellinger, J.; Benjamin, D.; Beretvas, A.; Beringer, J.; Bhatti, A.; Binkley, M.; Bisello, D.; Bizjak, I.; Blair, R. E.; Blocker, C.; Blumenfeld, B.; Bocci, A.; Bodek, A.; Boisvert, V.; Bolla, G.; Bortoletto, D.; Boudreau, J.; Boveia, A.; Brau, B.; Bridgeman, A.; Brigliadori, L.; Bromberg, C.; Brubaker, E.; Budagov, J.; Budd, H. S.; Budd, S.; Burke, S.; Burkett, K.; Busetto, G.; Bussey, P.; Buzatu, A.; Byrum, K. L.; Cabrera, S.; Calancha, C.; Campanelli, M.; Campbell, M.; Canelli, F.; Canepa, A.; Carls, B.; Carlsmith, D.; Carosi, R.; Carrillo, S.; Carron, S.; Casal, B.; Casarsa, M.; Castro, A.; Catastini, P.; Cauz, D.; Cavaliere, V.; Cavalli-Sforza, M.; Cerri, A.; Cerrito, L.; Chang, S. H.; Chen, Y. C.; Chertok, M.; Chiarelli, G.; Chlachidze, G.; Chlebana, F.; Cho, K.; Chokheli, D.; Chou, J. P.; Choudalakis, G.; Chuang, S. H.; Chung, K.; Chung, W. H.; Chung, Y. S.; Chwalek, T.; Ciobanu, C. I.; Ciocci, M. A.; Clark, A.; Clark, D.; Compostella, G.; Convery, M. E.; Conway, J.; Cordelli, M.; Cortiana, G.; Cox, C. A.; Cox, D. J.; Crescioli, F.; Almenar, C. Cuenca; Cuevas, J.; Culbertson, R.; Cully, J. C.; Dagenhart, D.; Datta, M.; Davies, T.; de Barbaro, P.; de Cecco, S.; Deisher, A.; de Lorenzo, G.; Dell'Orso, M.; Deluca, C.; Demortier, L.; Deng, J.; Deninno, M.; Derwent, P. F.; di Canto, A.; di Giovanni, G. P.; Dionisi, C.; di Ruzza, B.; Dittmann, J. R.; D'Onofrio, M.; Donati, S.; Dong, P.; Donini, J.; Dorigo, T.; Dube, S.; Efron, J.; Elagin, A.; Erbacher, R.; Errede, D.; Errede, S.; Eusebi, R.; Fang, H. C.; Farrington, S.; Fedorko, W. T.; Feild, R. G.; Feindt, M.; Fernandez, J. P.; Ferrazza, C.; Field, R.; Flanagan, G.; Forrest, R.; Frank, M. J.; Franklin, M.; Freeman, J. C.; Furic, I.; Gallinaro, M.; Galyardt, J.; Garberson, F.; Garcia, J. E.; Garfinkel, A. F.; Garosi, P.; Genser, K.; Gerberich, H.; Gerdes, D.; Gessler, A.; Giagu, S.; Giakoumopoulou, V.; Giannetti, P.; Gibson, K.; Gimmell, J. L.; Ginsburg, C. M.; Giokaris, N.; Giordani, M.; Giromini, P.; Giunta, M.; Giurgiu, G.; Glagolev, V.; Glenzinski, D.; Gold, M.; Goldschmidt, N.; Golossanov, A.; Gomez, G.; Gomez-Ceballos, G.; Goncharov, M.; González, O.; Gorelov, I.; Goshaw, A. T.; Goulianos, K.; Gresele, A.; Grinstein, S.; Grosso-Pilcher, C.; Group, R. C.; Grundler, U.; Guimaraes da Costa, J.; Gunay-Unalan, Z.; Haber, C.; Hahn, K.; Hahn, S. R.; Halkiadakis, E.; Han, B.-Y.; Han, J. Y.; Happacher, F.; Hara, K.; Hare, D.; Hare, M.; Harper, S.; Harr, R. F.; Harris, R. M.; Hartz, M.; Hatakeyama, K.; Hays, C.; Heck, M.; Heijboer, A.; Heinemann, B.; Heinrich, J.; Henderson, C.; Herndon, M.; Heuser, J.; Hewamanage, S.; Hidas, D.; Hill, C. S.; Hirschbuehl, D.; Hocker, A.; Hou, S.; Houlden, M.; Hsu, S.-C.; Huffman, B. T.; Hughes, R. E.; Husemann, U.; Hussein, M.; Huston, J.; Incandela, J.; Introzzi, G.; Iori, M.; Ivanov, A.; James, E.; Jang, D.; Jayatilaka, B.; Jeon, E. J.; Jha, M. K.; Jindariani, S.; Johnson, W.; Jones, M.; Joo, K. K.; Jun, S. Y.; Jung, J. E.; Junk, T. R.; Kamon, T.; Kar, D.; Karchin, P. E.; Kato, Y.; Kephart, R.; Ketchum, W.; Keung, J.; Khotilovich, V.; Kilminster, B.; Kim, D. H.; Kim, H. S.; Kim, H. W.; Kim, J. E.; Kim, M. J.; Kim, S. B.; Kim, S. H.; Kim, Y. K.; Kimura, N.; Kirsch, L.; Klimenko, S.; Knuteson, B.; Ko, B. R.; Kondo, K.; Kong, D. J.; Konigsberg, J.; Korytov, A.; Kotwal, A. V.; Kreps, M.; Kroll, J.; Krop, D.; Krumnack, N.; Kruse, M.; Krutelyov, V.; Kubo, T.; Kuhr, T.; Kulkarni, N. P.; Kurata, M.; Kwang, S.; Laasanen, A. T.; Lami, S.; Lammel, S.; Lancaster, M.; Lander, R. L.; Lannon, K.; Lath, A.; Latino, G.; Lazzizzera, I.; Lecompte, T.; Lee, E.; Lee, H. S.; Lee, S. W.; Leone, S.; Lewis, J. D.; Lin, C.-S.; Linacre, J.; Lindgren, M.; Lipeles, E.; Lister, A.; Litvintsev, D. O.; Liu, C.; Liu, T.; Lockyer, N. S.; Loginov, A.; Loreti, M.; Lovas, L.; Lucchesi, D.; Luci, C.; Lueck, J.; Lujan, P.; Lukens, P.; Lungu, G.; Lyons, L.; Lys, J.; Lysak, R.; MacQueen, D.; Madrak, R.; Maeshima, K.; Makhoul, K.; Maki, T.; Maksimovic, P.; Malde, S.; Malik, S.; Manca, G.; Manousakis-Katsikakis, A.; Margaroli, F.; Marino, C.; Marino, C. P.; Martin, A.; Martin, V.; Martínez, M.; Martínez-Ballarín, R.; Maruyama, T.; Mastrandrea, P.; Masubuchi, T.; Mathis, M.; Mattson, M. E.; Mazzanti, P.; McFarland, K. S.; McIntyre, P.; McNulty, R.; Mehta, A.; Mehtala, P.; Menzione, A.; Merkel, P.; Mesropian, C.; Miao, T.; Miladinovic, N.; Miller, R.; Mills, C.; Milnik, M.; Mitra, A.; Mitselmakher, G.; Miyake, H.; Moggi, N.; Mondragon, M. N.; Moon, C. S.; Moore, R.; Morello, M. J.; Morlock, J.; Fernandez, P. Movilla; Mülmenstädt, J.; Mukherjee, A.; Muller, Th.; Mumford, R.; Murat, P.; Mussini, M.; Nachtman, J.; Nagai, Y.; Nagano, A.; Naganoma, J.; Nakamura, K.; Nakano, I.; Napier, A.; Necula, V.; Nett, J.; Neu, C.; Neubauer, M. S.; Neubauer, S.; Nielsen, J.; Nodulman, L.; Norman, M.; Norniella, O.; Nurse, E.; Oakes, L.; Oh, S. H.; Oh, Y. D.; Oksuzian, I.; Okusawa, T.; Orava, R.; Osterberg, K.; Griso, S. Pagan; Palencia, E.; Papadimitriou, V.; Papaikonomou, A.; Paramonov, A. A.; Parks, B.; Pashapour, S.; Patrick, J.; Pauletta, G.; Paulini, M.; Paus, C.; Peiffer, T.; Pellett, D. E.; Penzo, A.; Phillips, T. J.; Piacentino, G.; Pianori, E.; Pinera, L.; Pitts, K.; Plager, C.; Pondrom, L.; Poukhov, O.; Pounder, N.; Prakoshyn, F.; Pronko, A.; Proudfoot, J.; Ptohos, F.; Pueschel, E.; Punzi, G.; Pursley, J.; Rademacker, J.; Rahaman, A.; Ramakrishnan, V.; Ranjan, N.; Redondo, I.; Renton, P.; Renz, M.; Rescigno, M.; Richter, S.; Rimondi, F.; Ristori, L.; Robson, A.; Rodrigo, T.; Rodriguez, T.; Rogers, E.; Rolli, S.; Roser, R.; Rossi, M.; Rossin, R.; Roy, P.; Ruiz, A.; Russ, J.; Rusu, V.; Rutherford, B.; Saarikko, H.; Safonov, A.; Sakumoto, W. K.; Saltó, O.; Santi, L.; Sarkar, S.; Sartori, L.; Sato, K.; Savoy-Navarro, A.; Schlabach, P.; Schmidt, A.; Schmidt, E. E.; Schmidt, M. A.; Schmidt, M. P.; Schmitt, M.; Schwarz, T.; Scodellaro, L.; Scribano, A.; Scuri, F.; Sedov, A.; Seidel, S.; Seiya, Y.; Semenov, A.; Sexton-Kennedy, L.; Sforza, F.; Sfyrla, A.; Shalhout, S. Z.; Shears, T.; Shepard, P. F.; Shimojima, M.; Shiraishi, S.; Shochet, M.; Shon, Y.; Shreyber, I.; Sinervo, P.; Sisakyan, A.; Slaughter, A. J.; Slaunwhite, J.; Sliwa, K.; Smith, J. R.; Snider, F. D.; Snihur, R.; Soha, A.; Somalwar, S.; Sorin, V.; Spreitzer, T.; Squillacioti, P.; Stanitzki, M.; St. Denis, R.; Stelzer, B.; Stelzer-Chilton, O.; Stentz, D.; Strologas, J.; Strycker, G. L.; Suh, J. S.; Sukhanov, A.; Suslov, I.; Suzuki, T.; Taffard, A.; Takashima, R.; Takeuchi, Y.; Tanaka, R.; Tecchio, M.; Teng, P. K.; Terashi, K.; Thom, J.; Thompson, A. S.; Thompson, G. A.; Thomson, E.; Tipton, P.; Ttito-Guzmán, P.; Tkaczyk, S.; Toback, D.; Tokar, S.; Tollefson, K.; Tomura, T.; Tonelli, D.; Torre, S.; Torretta, D.; Totaro, P.; Tourneur, S.; Trovato, M.; Tsai, S.-Y.; Tu, Y.; Turini, N.; Ukegawa, F.; Vallecorsa, S.; van Remortel, N.; Varganov, A.; Vataga, E.; Vázquez, F.; Velev, G.; Vellidis, C.; Vidal, M.; Vidal, R.; Vila, I.; Vilar, R.; Vine, T.; Vogel, M.; Volobouev, I.; Volpi, G.; Wagner, P.; Wagner, R. G.; Wagner, R. L.; Wagner, W.; Wagner-Kuhr, J.; Wakisaka, T.; Wallny, R.; Wang, S. M.; Warburton, A.; Waters, D.; Weinberger, M.; Weinelt, J.; Wester, W. C., III; Whitehouse, B.; Whiteson, D.; Wicklund, A. B.; Wicklund, E.; Wilbur, S.; Williams, G.; Williams, H. H.; Wilson, P.; Winer, B. L.; Wittich, P.; Wolbers, S.; Wolfe, C.; Wright, T.; Wu, X.; Würthwein, F.; Xie, S.; Yagil, A.; Yamamoto, K.; Yamaoka, J.; Yang, U. K.; Yang, Y. C.; Yao, W. M.; Yeh, G. P.; Yi, K.; Yoh, J.; Yorita, K.; Yoshida, T.; Yu, G. B.; Yu, I.; Yu, S. S.; Yun, J. C.; Zanello, L.; Zanetti, A.; Zhang, X.; Zheng, Y.; Zucchelli, S.

    2009-08-01

    We present the first observation in hadronic collisions of the electroweak production of vector boson pairs (VV, V=W, Z) where one boson decays to a dijet final state. The data correspond to 3.5fb-1 of integrated luminosity of p pmacr collisions at s=1.96TeV collected by the CDF II detector at the Fermilab Tevatron. We observe 1516±239(stat)±144(syst) diboson candidate events and measure a cross section σ(p pmacr →VV+X) of 18.0±2.8(stat)±2.4(syst)±1.1(lumi)pb, in agreement with the expectations of the standard model.

  10. Luminosity, Energy and Polarization Studies for the Linear Collider: Comparing e+e- and e-e- for NLC and TESLA

    SciTech Connect

    Woods, M

    2004-02-25

    We present results from luminosity, energy and polarization studies at a future Linear Collider. We compare e{sup +}e{sup -} and e{sup -}e{sup -} modes of operation and consider both NLC and TESLA beam parameter specifications at a center-of-mass energy of 500 GeV. Realistic colliding beam distributions are used, which include dynamic effects of the beam transport from the Damping Rings to the Interaction Point. Beam-beam deflections scans and their impact for beam-based feedbacks are considered. A transverse kink instability is studied, including its impact on determining the luminosity-weighted center-of-mass energy. Polarimetry in the extraction line from the IP is presented, including results on beam distributions at the Compton IP and at the Compton detector.

  11. Phase detector and phase feedback for a single bunch in a two-bunch damping ring for the SLAC Linear Collider

    SciTech Connect

    Schwarz, H.D.; Judkins, J.G.

    1987-03-01

    The synchronous phase of a bunch of positrons or electrons being damped in a SLAC Linear Collider (SLC) damping ring is dependent on beam intensity. Injection for alternate bunches into the SLC linac from the damping rings should occur at a constant phase. A phase detector was developed allowing the measurement of phase of a single-stored bunch in the presence of a second bunch in reference to the phase of the linac. The single-bunch phase is derived from beam position monitor signals using a switching scheme to separate the two bunches circulating in each damping ring. The hardware is described including feedback loops to stabilize the extraction phase.

  12. Pair Production of the Doubly Charged Leptons Associated with a Gauge Boson γ or Z in e+e- and γγ Collisions at Future Linear Colliders

    NASA Astrophysics Data System (ADS)

    Zeng, Qing-Guo; Ji, Li; Yang, Shuo

    2015-03-01

    In this paper, we investigate the production of a pair of doubly charged leptons associated with a gauge boson V(γ or Z) at future linear colliders via e+e- and γγ collisions. The numerical results show that the possible signals of the doubly charged leptons may be detected via the processes e+e- → VX++X-- and γγ → VX++X-- at future ILC or CLIC experiments. Supported in part by the National Natural Science Foundation of China under Grants Nos. 11275088, 11205023, 11375248 and the Program for Liaoning Excellent Talents in University under Grant No. LJQ2014135

  13. Preliminary design report of a relativistic-Klystron two-beam-accelerator based power source for a 1 TeV center-of-mass next linear collider

    SciTech Connect

    Yu, S.; Goffeney, N.; Henestroza, E.

    1995-02-22

    A preliminary point design for an 11.4 GHz power source for a 1 TeV center-of-mass Next Linear Collider (NLC) based on the Relativistic-Klystron Two-Beam-Accelerator (RK-TBA) concept is presented. The present report is the result of a joint LBL-LLNL systems study. consisting of three major thrust areas: physics, engineering, and costing. The new RK-TBA point design, together with our findings in each of these areas, are reported.

  14. Fifth SIAM conference on applied linear algebra. Final report

    SciTech Connect

    Lewis, J.G.; Gilbert, J.R.; Parlett, B.N.

    1994-11-16

    The SIAM Conferences on Applied Linear Algebra are the centerpiece of activities for the SIAG on Linear Algebra. They are held every three years and bring together a diverse group of applied linear algebraists, representing industry, government and academics in both matrix theory and matrix computations. This sequence of conferences has two related goals: (1) to be useful and interesting to linear algebraists of every area of specialization, and, (2) to develop and expose connections among problems in different areas. Many aspects of the 1994 conference were carefully chosen to enhance interchange between the various groups and yet still provide a solid focus on specialities. The organizing committee adopted a new meeting structure to resolve the conflict between these two goals at earlier meetings in the series. We have prepared this report for others who may wish to consider our structure as an alternative to more traditional arrangements.

  15. 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.

  16. LDRD final report : autotuning for scalable linear algebra.

    SciTech Connect

    Heroux, Michael Allen; Marker, Bryan

    2011-09-01

    This report summarizes the progress made as part of a one year lab-directed research and development (LDRD) project to fund the research efforts of Bryan Marker at the University of Texas at Austin. The goal of the project was to develop new techniques for automatically tuning the performance of dense linear algebra kernels. These kernels often represent the majority of computational time in an application. The primary outcome from this work is a demonstration of the value of model driven engineering as an approach to accurately predict and study performance trade-offs for dense linear algebra computations.

  17. 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.

  18. Linear and Nonlinear MHD Wave Processes in Plasmas. Final Report

    SciTech Connect

    Tataronis, J. A.

    2004-06-01

    This program treats theoretically low frequency linear and nonlinear wave processes in magnetized plasmas. A primary objective has been to evaluate the effectiveness of MHD waves to heat plasma and drive current in toroidal configurations. The research covers the following topics: (1) the existence and properties of the MHD continua in plasma equilibria without spatial symmetry; (2) low frequency nonresonant current drive and nonlinear Alfven wave effects; and (3) nonlinear electron acceleration by rf and random plasma waves. Results have contributed to the fundamental knowledge base of MHD activity in symmetric and asymmetric toroidal plasmas. Among the accomplishments of this research effort, the following are highlighted: Identification of the MHD continuum mode singularities in toroidal geometry. Derivation of a third order ordinary differential equation that governs nonlinear current drive in the singular layers of the Alfvkn continuum modes in axisymmetric toroidal geometry. Bounded solutions of this ODE implies a net average current parallel to the toroidal equilibrium magnetic field. Discovery of a new unstable continuum of the linearized MHD equation in axially periodic circular plasma cylinders with shear and incompressibility. This continuum, which we named “accumulation continuum” and which is related to ballooning modes, arises as discrete unstable eigenfrequency accumulate on the imaginary frequency axis in the limit of large mode numbers. Development of techniques to control nonlinear electron acceleration through the action of multiple coherent and random plasmas waves. Two important elements of this program aye student participation and student training in plasma theory.

  19. Searches for new neutral gauge Z' bosons at the e{sup +}e{sup -} International Linear Collider and their identification

    SciTech Connect

    Babich, A. A. Pankov, A. A. Tsytrinov, A. V. Karpenko, N. V.

    2010-05-15

    The potential of the electron-positron International Linear Collider for searches for and the separation of signals induced by new neutral gauge bosons predicted by various classes of models featuring an extended gauge sector is investigated. The analysis presented in this article was performed for processes of annihilation fermion-pair production and was based on the use of differential polarization observables, which ensure a higher sensitivity (in relation to integrated observables) of the processes being considered to Z'-boson parameters. Thresholds for discovering and identifying new neutral gauge bosons associated with models belonging to the E{sub 6} and LR, as well as the ALR and SSM, classes are determined. In particular, it is shown that polarization experiments at a 0.5-TeV electron-positron collider of integrated luminosity 100 fb{sup -1} would make it possible to identify unambiguously the entire set of Z'-boson models (Z'{sub SSM}, Z'{sub {phi}}, Z'{sub {eta}}, Z'{sub {chi}}, Z'{sub LRS}, and Z'{sub ALR}) for M{sub Z'} < 6{radical}s and to improve considerably the respective estimates expected from experiments with unpolarized particles.

  20. LEPTON ACCELERATORS AND COLLIDERS: Linear optics calibration and nonlinear optimization during the commissioning of the SSRF storage ring

    NASA Astrophysics Data System (ADS)

    Tian, Shun-Qiang; Zhang, Wen-Zhi; Li, Hao-Hu; Zhang, Man-Zhou; Hou, Jie; Zhou, Xue-Mei; Liu, Gui-Min

    2009-06-01

    Phase I commissioning of the SSRF storage ring on 3.0 GeV beam energy was started at the end of December 2007. A lot of encouraging results have been obtained so far. In this paper, calibrations of the linear optics during the commissioning are discussed, and some measured results about the nonlinearity given. Calibration procedure emphasizes correcting quadrupole magnetic coefficients with the Linear Optics from Closed Orbit (LOCO) technique. After fitting the closed orbit response matrix, the linear optics of the four test modes is substantially corrected, and the measured physical parameters agree well with the designed ones.

  1. Electromagnetic characterization of nonevaporable getter properties between 220-330 and 500-750 GHz for the Compact Linear Collider damping rings

    NASA Astrophysics Data System (ADS)

    Koukovini-Platia, E.; Rumolo, G.; Zannini, C.

    2017-01-01

    Due to its effective pumping ability, nonevaporable getter (NEG) coating is considered for the vacuum chambers of the Compact Linear Collider (CLIC) electron damping rings (EDR). The aim is to suppress fast beam ion instabilities. The electromagnetic (EM) characterization of the NEG properties up to ultra-high frequencies is required for the correct impedance modeling of the damping ring (DR) components. The properties are determined using rectangular waveguides which are coated with NEG. The method is based on a combination of complex transmission coefficient S21 measurements with a vector network analyzer (VNA) and 3D simulations using CST Microwave Studio® (CST MWS). The frequency ranges discussed in this paper are 220-330 and 500-750 GHz.

  2. Sixth SIAM conference on applied linear algebra: Final program and abstracts. Final technical report

    SciTech Connect

    1997-12-31

    Linear algebra plays a central role in mathematics and applications. The analysis and solution of problems from an amazingly wide variety of disciplines depend on the theory and computational techniques of linear algebra. In turn, the diversity of disciplines depending on linear algebra also serves to focus and shape its development. Some problems have special properties (numerical, structural) that can be exploited. Some are simply so large that conventional approaches are impractical. New computer architectures motivate new algorithms, and fresh ways to look at old ones. The pervasive nature of linear algebra in analyzing and solving problems means that people from a wide spectrum--universities, industrial and government laboratories, financial institutions, and many others--share an interest in current developments in linear algebra. This conference aims to bring them together for their mutual benefit. Abstracts of papers presented are included.

  3. Muon colliders

    NASA Astrophysics Data System (ADS)

    Palmer, R. B.; Sessler, A.; Skrinsky, A.; Tollestrup, A.; Baltz, A. J.; Chen, P.; Cheng, W.-H.; Cho, Y.; Courant, E.; Fernow, R. C.; Gallardo, J. C.; Garren, A.; Green, M.; Kahn, S.; Kirk, H.; Lee, Y. Y.; Mills, F.; Mokhov, N.; Morgan, G.; Neuffer, D.; Noble, R.; Norem, J.; Popovic, M.; Schachinger, L.; Silvestrov, G.; Summers, D.; Stumer, I.; Syphers, M.; Torun, Y.; Trbojevic, D.; Turner, W.; Van Ginneken, A.; Vsevolozhskaya, T.; Weggel, R.; Willen, E.; Winn, D.; Wurtele, J.

    1996-05-01

    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 μ+μ- 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.

  4. 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.

  5. 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.

  6. Focusing of submicron beams for TeV-scale {ital e}{sup +}{ital e}{sup {minus}} linear colliders

    SciTech Connect

    Balakin, V.; Alexandrov, V.A.; Mikhailichenko, A.; Floettmann, K.; Peters, F.; Voss, G.; Bharadwaj, V.; Halling, M.; Holt, J.A.; Buon, J.; Jeanjean, J.; LeDiberder, F.; Lepeltier, V.; Puzo, P.; Heimlinger, G.; Settles, R.; Stierlin, U.; Hayano, H.; Ishihara, N.; Nakayama, H.; Oide, K.; Shintake, T.; Takeuchi, Y.; Yamamoto, N.; Bulos, F.; Burke, D.; Field, R.; Hartman, S.; Helm, R.; Irwin, J.; Iverson, R.; Rokni, S.; Roy, G.; Spence, W.; Tenenbaum, P.; Wagner, S.R.; Walz, D.; Williams, S.

    1995-03-27

    First experimental results from the final focus test beam (FFTB) are reported. The vertical dimension of a 47-GeV electron beam from the SLAC linac has been reduced at the focal point of the FFTB by a demagnification of 320 to a beam height of approximately 70 nm.

  7. A high-granularity plastic scintillator tile hadronic calorimeter with APD readout for a linear collider detector

    NASA Astrophysics Data System (ADS)

    Andreev, V.; Cvach, J.; Danilov, M.; Devitsin, E.; Dodonov, V.; Eigen, G.; Garutti, E.; Gilitzky, Yu.; Groll, M.; Heuer, R.-D.; Janata, M.; Kacl, I.; Korbel, V.; Kozlov, V.; Meyer, H.; Morgunov, V.; Němeček, S.; Pöschl, R.; Polák, I.; Raspereza, A.; Reiche, S.; Rusinov, V.; Sefkow, F.; Smirnov, P.; Terkulov, A.; Valkár, Š.; Weichert, J.; Zálešák, J.

    2006-08-01

    We report upon the performance of an analog hadron calorimeter prototype, where plastic scintillator tiles are read out with wavelength-shifting fibers coupled to avalanche photodiodes. This prototype configuration has been tested using a positron beam at DESY with energies between 1 and 6 GeV. We present different detector calibration methods, show measurements for noise, linearity, and energy resolution and discuss gain monitoring with an LED system. The results are in good agreement with our simulation studies and previous measurements using silicon photomultiplier readout.

  8. Linear Collider Test Facility: Twiss Parameter Analysis at the IP/Post-IP Location of the ATF2 Beam Line

    SciTech Connect

    Bolzon, Benoit; Jeremie, Andrea; Bai, Sha; Bambade, Philip; White, Glen; /SLAC

    2012-07-02

    At the first stage of the ATF2 beam tuning, vertical beam size is usually bigger than 3 {micro}m at the IP. Beam waist measurements using wire scanners and a laser wire are usually performed to check the initial matching of the beam through to the IP. These measurements are described in this paper for the optics currently used ({beta}{sub x} = 4cm and {beta}{sub y} = 1mm). Software implemented in the control room to automate these measurements with integrated analysis is also described. Measurements showed that {beta} functions and emittances were within errors of measurements when no rematching and coupling corrections were done. However, it was observed that the waist in the horizontal (X) and vertical (Y) plane was abnormally shifted and simulations were performed to try to understand these shifts. They also showed that multiknobs are needed in the current optics to correct simultaneously {alpha}{sub x}, {alpha}{sub y} and the horizontal dispersion (D{sub x}). Such multiknobs were found and their linearity and orthogonality were successfully checked using MAD optics code. The software for these multiknobs was implemented in the control room and waist scan measurements using the {alpha}{sub y} knob were successfully performed.

  9. 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

  10. Study of the performance of a compact sandwich calorimeter for the instrumentation of the very forward region of a future linear collider detector

    NASA Astrophysics Data System (ADS)

    Ghenescu, V.; Benhammou, Y.

    2017-02-01

    The FCAL collaboration is preparing large scale prototypes of special calorimeters to be used in the very forward region at a future linear electron positron collider for a precise and fast luminosity measurement and beam-tuning. These calorimeters are designed as sensor-tungsten calorimeters with very thin sensor planes to keep the Moliere radius small and dedicated FE electronics to match the timing and dynamic range requirements. A partially instrumented prototype was investigated in the CERN PS T9 beam in 2014 and at the DESY-II Synchrotron in 2015. It was operated in a mixed particle beam (electrons, muons and hadrons) of 5 GeV from PS facilities and with secondary electrons of 5 GeV energy from DESY-II. The results demonstrated a very good performance of the full readout chain. The high statistics data were used to study the response to different particles, perform sensor alignment and measure the longitudinal shower development in the sandwich. In addition, Geant4 MC simulations were done, and compared to the data.

  11. Prompt J /ψ production in association with a c c ¯ pair within the framework of nonrelativistic QCD via photon-photon collisions at the International Linear Collider

    NASA Astrophysics Data System (ADS)

    Sun, Zhan; Wu, Xing-Gang; Zhang, Hong-Fei

    2015-10-01

    We present a systematical study on the prompt J /ψ production in association with a c c ¯ pair via the process, γ γ →H (c c ¯)+c +c ¯, within the framework of nonrelativistic QCD at the future high-energy e+e- collider—International Linear Collider (ILC), including both direct and feed-down contributions. For direct J /ψ production, the states with color-octet channels, especially the P3 J[8] and S1 0[8] ones, provide a dominant contribution to the production cross section, which are about 52 times over that of the color-singlet one. This is clearly shown by the transverse momentum (pt) and rapidity distributions. The feed-down contribution from ψ' and χc J (J =0 , 1, 2) is sizable, which is about 20% to the total prompt cross section. Besides the yields, we also calculate the J /ψ polarization parameter λ . In the small pt region, the polarization of the prompt J /ψ is longitudinal due to large contributions through the P3 J[8] channel, and becomes transverse in the high pt region due to the S3 1[8] channel. Thus the J /ψ production via photon-photon collisions at the ILC shall provide a useful platform for testing the color-octet mechanism.

  12. Functional Requirements on the Design of the Detectors and the Interaction Region of an e e- Linear Collider with a Push-Pull Arrangement of Detectors

    SciTech Connect

    Parker, B.; Mikhailichenko, A.; Buesser, K.; Hauptman, J.; Tauchi, T.; Burrows, P.; Markiewicz, T.; Oriunno, M.; Seryi, A.; Markiewicz, T.; /SLAC

    2009-06-02

    The Interaction Region of the International Linear Collider is based on two experimental detectors working in a push-pull mode. A time efficient implementation of this model sets specific requirements and challenges for many detector and machine systems, in particular the IR magnets, the cryogenics and the alignment system, the beamline shielding, the detector design and the overall integration. This paper attempts to separate the functional requirements of a push pull interaction region and machine detector interface from any particular conceptual or technical solution that might have been proposed to date by either the ILC Beam Delivery Group or any of the three detector concepts. As such, we hope that it provides a set of ground rules for interpreting and evaluating the MDI parts of the proposed detector concept's Letters of Intent, due March 2009. The authors of the present paper are the leaders of the IR Integration Working Group within Global Design Effort Beam Delivery System and the representatives from each detector concept submitting the Letters Of Intent.

  13. 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.

  14. Beam rounders for circular colliders

    SciTech Connect

    A. Burov and S. Nagaitsev

    2002-12-10

    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.

  15. Review of project definition studies of possible on-site uses of superconducting super collider assets and facilities. Final report

    SciTech Connect

    1994-12-01

    This document reports on the results of a peer review and evaluation of studies made of potential uses of assets from the terminated Superconducting Super Collider (SSC) project. These project definition studies focused on nine areas of use of major assets and facilities at the SSC site near Waxahachie, Texas. The studies were undertaken as part of the effort to maximize the value of the investment made in the SSC and were supported by two sets of grants, one to the Texas National Research Laboratory Commission (TNRLC) and the second to various universities and other institutions for studies of ideas raised by a public call for expressions of interest. The Settlement Agreement, recently signed by the Department of Energy (DOE) and TNRLC, provides for a division of SSC property. As part of the goal of maximizing the value of the SSC investment, the findings contained in this report are thus addressed to officials in both the Department and TNRLC. In addition, this review had several other goals: to provide constructive feedback to those doing the studies; to judge the benefits and feasibility (including funding prospects) of the projects studied; and to help worthy projects become reality by matching projects with possible funding sources.

  16. 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.

  17. Future colliders

    SciTech Connect

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

    1996-10-01

    The high energy physics advantages, disadvantages and luminosity requirements of hadron (pp, pp), of lepton (e{sup +}e{sup {minus}}, {mu}{sup +} {mu}{sup {minus}}) and photon-photon colliders are considered. Technical arguments for increased energy in each type of machine are presented. Their relative size, and the implications of size on cost are discussed.

  18. Accelerator aspects of photon colliders at TESLA

    NASA Astrophysics Data System (ADS)

    Walker, Nicholas J.

    2001-10-01

    The TESLA linear collider is being primarily designed as a 500- 800 GeV centre of mass e +e - linear collider. However, a second interaction region is being incorporated into the design with a crossing angle of 32 mrad, which is suitable for use as a γγ collider. In this paper we will review those aspects of the current machine design which are critical to the operation of TESLA as a photon collider, paying particular attention to the preservation of small horizontal emittances, and—in the absence of beamstrahlung—limits on reduced horizontal beam cross-section at the interaction point.

  19. 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.

  20. New NLC Final Focus

    SciTech Connect

    Raimondi, P.

    2004-10-11

    A novel design of the Final Focus has recently been proposed [1] and has been adopted now for the Next Linear Collider [2]. This new design has fewer optical elements and is much shorter, nonetheless achieving better chromatic properties. In this paper, the new final focus system is briefly discussed stressing one particular characteristic of the new design--its multi TeV energy reach.

  1. Proposed Physics Experiments for Laser-Driven Electron Linear Acceleration in a Dielectric Loaded Vacuum, Final Report

    SciTech Connect

    Byer, Robert L.

    2016-07-08

    This final report summarizes the last three years of research on the development of advanced linear electron accelerators that utilize dielectric wave-guide vacuum channels pumped by high energy laser fields to accelerate beams of electrons.

  2. 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.

  3. Linear state feedback, quadratic weights, and closed loop eigenstructures. M.S. Thesis. Final Report

    NASA Technical Reports Server (NTRS)

    Thompson, P. M.

    1980-01-01

    Equations are derived for the angles of general multivariable root loci and linear quadratic optimal root loci, including angles of departure and approach. The generalized eigenvalue problem is used to compute angles of approach. Equations are also derived to find the sensitivity of closed loop eigenvalue and the directional derivatives of closed loop eigenvectors. An equivalence class of quadratic weights that produce the same asymptotic eigenstructure is defined, a canonical element is defined, and an algorithm to find it is given. The behavior of the optimal root locus in the nonasymptotic region is shown to be different for quadratic weights with the same asymptotic properties. An algorithm is presented that can be used to select a feedback gain matrix for the linear state feedback problem which produces a specified asymptotic eigenstructure. Another algorithm is given to compute the asymptotic eigenstructure properties inherent in a given set of quadratic weights. Finally, it is shown that optimal root loci for nongeneric problems can be approximated by generic ones in the nonasymptotic region.

  4. SSC [Superconducting Super Collider] Project: Technical Training for the Future of Texas. Navarro College/Dallas Community College District. Final Report for Year One.

    ERIC Educational Resources Information Center

    Orsak, Charles; McGlohen, Patti J.

    The Superconducting Super Collider Laboratory (SSCL) is a national lab for research on the fundamental forces and constituents of the universe. A major part of the research will involve an oval ring 54 miles in circumference through which superconducting magnets will steer two beams of protons in opposite directions. In response to the…

  5. SLAC electron-positron colliders: present and future

    SciTech Connect

    Richter, B.

    1986-09-01

    Stanford University's colliding beam program is outlined, including the SPEAR and PEP colliders and the SLAC linear collider. The accelerator developments to be pursued on these facilities are discussed, as well as advanced accelerator research and development. The items covered in the advanced accelerator research include beamstrahlung, stability requirements, breakdown limits, and power sources. (LEW)

  6. 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.

  7. Collective accelerator for electron colliders

    SciTech Connect

    Briggs, R.J.

    1985-05-13

    A recent concept for collective acceleration and focusing of a high energy electron bunch is discussed, in the context of its possible applicability to large linear colliders in the TeV range. The scheme can be considered to be a member of the general class of two-beam accelerators, where a high current, low voltage beam produces the acceleration fields for a trailing high energy bunch.

  8. 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.

  9. EZLP: An Interactive Computer Program for Solving Linear Programming Problems. Final Report.

    ERIC Educational Resources Information Center

    Jarvis, John J.; And Others

    Designed for student use in solving linear programming problems, the interactive computer program described (EZLP) permits the student to input the linear programming model in exactly the same manner in which it would be written on paper. This report includes a brief review of the development of EZLP; narrative descriptions of program features,…

  10. LDRD final report on massively-parallel linear programming : the parPCx system.

    SciTech Connect

    Parekh, Ojas; Phillips, Cynthia Ann; Boman, Erik Gunnar

    2005-02-01

    This report summarizes the research and development performed from October 2002 to September 2004 at Sandia National Laboratories under the Laboratory-Directed Research and Development (LDRD) project ''Massively-Parallel Linear Programming''. We developed a linear programming (LP) solver designed to use a large number of processors. LP is the optimization of a linear objective function subject to linear constraints. Companies and universities have expended huge efforts over decades to produce fast, stable serial LP solvers. Previous parallel codes run on shared-memory systems and have little or no distribution of the constraint matrix. We have seen no reports of general LP solver runs on large numbers of processors. Our parallel LP code is based on an efficient serial implementation of Mehrotra's interior-point predictor-corrector algorithm (PCx). The computational core of this algorithm is the assembly and solution of a sparse linear system. We have substantially rewritten the PCx code and based it on Trilinos, the parallel linear algebra library developed at Sandia. Our interior-point method can use either direct or iterative solvers for the linear system. To achieve a good parallel data distribution of the constraint matrix, we use a (pre-release) version of a hypergraph partitioner from the Zoltan partitioning library. We describe the design and implementation of our new LP solver called parPCx and give preliminary computational results. We summarize a number of issues related to efficient parallel solution of LPs with interior-point methods including data distribution, numerical stability, and solving the core linear system using both direct and iterative methods. We describe a number of applications of LP specific to US Department of Energy mission areas and we summarize our efforts to integrate parPCx (and parallel LP solvers in general) into Sandia's massively-parallel integer programming solver PICO (Parallel Interger and Combinatorial Optimizer). We

  11. Muon collider design

    NASA Astrophysics Data System (ADS)

    Palmer, R.; Sessler, A.; Skrinsky, A.; Tollestrup, A.; Baltz, A.; Caspi, S.; P., Chen; W-H., Cheng; Y., Cho; Cline, D.; Courant, E.; Fernow, R.; Gallardo, J.; Garren, A.; Gordon, H.; Green, M.; Gupta, R.; Hershcovitch, A.; Johnstone, C.; Kahn, S.; Kirk, H.; Kycia, T.; Y., Lee; Lissauer, D.; Luccio, A.; McInturff, A.; Mills, F.; Mokhov, N.; Morgan, G.; Neuffer, D.; K-Y., Ng; Noble, R.; Norem, J.; Norum, B.; Oide, K.; Parsa, Z.; Polychronakos, V.; Popovic, M.; Rehak, P.; Roser, T.; Rossmanith, R.; Scanlan, R.; Schachinger, L.; Silvestrov, G.; Stumer, I.; Summers, D.; Syphers, M.; Takahashi, H.; Torun, Y.; Trbojevic, D.; Turner, W.; van Ginneken, A.; Vsevolozhskaya, T.; Weggel, R.; Willen, E.; Willis, W.; Winn, D.; Wurtele, J.; Zhao, Y.

    1996-11-01

    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 \\mu^+ \\mu^- 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. Detector background, polarization, and nonstandard operating conditions are discussed.

  12. The development of colliders

    SciTech Connect

    Sessler, A.M.

    1997-03-01

    During the period of the 50`s and the 60`s colliders were developed. Prior to that time there were no colliders, and by 1965 a number of small devices had worked, good understanding had been achieved, and one could speculate, as Gersh Budker did, that in a few years 20% of high energy physics would come from colliders. His estimate was an under-estimate, for now essentially all of high energy physics comes from colliders. The author presents a brief review of that history: sketching the development of the concepts, the experiments, and the technological advances which made it all possible.

  13. Search for a new resonance in the boosted di-Higgs to 4 bottom quarks final state at √s = 8 TeV using the ATLAS detector at the Large Hadron Collider

    NASA Astrophysics Data System (ADS)

    Zhou, Lei

    This thesis presents a search for a new, heavy particle decaying to a pair of Higgs bosons in the 4 bottom quarks final state at √ s=8 TeV. ATLAS detector at the Large Hadron Collider. The full data collected by ATLAS in 2012 at √s=8 TeV. is used, corresponding to a total luminosity of 19.5 fb-1. A novel technique, using smaller radius track jet to tag bottom quarks in combination with two large radius calorimeter jets to fully reconstruct boosted event topologies, significantly improves the sensitivity up to the mass scale of 2 TeV. In the absence of an excess, upper limits on the production cross section are set with 95% confidence level, using Kaluza-Klein gravitons in the bulk Randal-Sundrum model with coupling c ≡ k/MPl = 1.0 and 2.0 as benchmarks.

  14. 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

  15. Robust parallel iterative solvers for linear and least-squares problems, Final Technical Report

    SciTech Connect

    Saad, Yousef

    2014-01-16

    The primary goal of this project is to study and develop robust iterative methods for solving linear systems of equations and least squares systems. The focus of the Minnesota team is on algorithms development, robustness issues, and on tests and validation of the methods on realistic problems. 1. The project begun with an investigation on how to practically update a preconditioner obtained from an ILU-type factorization, when the coefficient matrix changes. 2. We investigated strategies to improve robustness in parallel preconditioners in a specific case of a PDE with discontinuous coefficients. 3. We explored ways to adapt standard preconditioners for solving linear systems arising from the Helmholtz equation. These are often difficult linear systems to solve by iterative methods. 4. We have also worked on purely theoretical issues related to the analysis of Krylov subspace methods for linear systems. 5. We developed an effective strategy for performing ILU factorizations for the case when the matrix is highly indefinite. The strategy uses shifting in some optimal way. The method was extended to the solution of Helmholtz equations by using complex shifts, yielding very good results in many cases. 6. We addressed the difficult problem of preconditioning sparse systems of equations on GPUs. 7. A by-product of the above work is a software package consisting of an iterative solver library for GPUs based on CUDA. This was made publicly available. It was the first such library that offers complete iterative solvers for GPUs. 8. We considered another form of ILU which blends coarsening techniques from Multigrid with algebraic multilevel methods. 9. We have released a new version on our parallel solver - called pARMS [new version is version 3]. As part of this we have tested the code in complex settings - including the solution of Maxwell and Helmholtz equations and for a problem of crystal growth.10. As an application of polynomial preconditioning we considered the

  16. 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.

  17. Mesoscale wide-bandwidth linear magnetic actuators : an LDRD final report.

    SciTech Connect

    Jones, Lawrence Anthony

    2004-02-01

    As MEMS transducers are scaled up in size, the threshold is quickly crossed to where magnetoquasistatic (MQS) transducers are superior for force production compared to electroquasistatic (EQS) transducers. Considerable progress has been made increasing the force output of MEMS EQS transducers, but progress with MEMS MQS transducers has been more modest. A key reason for this has been the difficulty implementing efficient lithographically-fabricated magnetic coil structures. The contribution of this study is a planar multilayer polyphase coil architecture which provides for the lithographic implementation of efficient stator windings suitable for linear magnetic machines. A millimeter-scale linear actuator with complex stator windings was fabricated using this architecture. The stators of the actuator were fabricated using a BCB/Cu process, which does not require replanarization of the wafer between layers. The prototype stator was limited to thin copper layers (3 {micro}m) due to the use of evaporated metal at the time of fabrication. Two layers of metal were implemented in the prototype, but the winding architecture naturally supports additional metal layer pairs. It was found in laboratory tests that the windings can support very high current densities of 4 x 10{sup 9}A/m{sup 2} without damage. Force production normal to the stator was calculated to be 0.54 N/A. For thin stators such as this one, force production increases approximately linearly with the thickness of the windings and a six-layer stator fabricated using a newly implemented electroplated BCB/Cu process (six layers of 15 {micro}m thick metal) is projected to produce approximately 8.8 N/A.

  18. Linear and nonlinear dynamic analysis by boundary element method. Ph.D. Thesis, 1986 Final Report

    NASA Technical Reports Server (NTRS)

    Ahmad, Shahid

    1991-01-01

    An advanced implementation of the direct boundary element method (BEM) applicable to free-vibration, periodic (steady-state) vibration and linear and nonlinear transient dynamic problems involving two and three-dimensional isotropic solids of arbitrary shape is presented. Interior, exterior, and half-space problems can all be solved by the present formulation. For the free-vibration analysis, a new real variable BEM formulation is presented which solves the free-vibration problem in the form of algebraic equations (formed from the static kernels) and needs only surface discretization. In the area of time-domain transient analysis, the BEM is well suited because it gives an implicit formulation. Although the integral formulations are elegant, because of the complexity of the formulation it has never been implemented in exact form. In the present work, linear and nonlinear time domain transient analysis for three-dimensional solids has been implemented in a general and complete manner. The formulation and implementation of the nonlinear, transient, dynamic analysis presented here is the first ever in the field of boundary element analysis. Almost all the existing formulation of BEM in dynamics use the constant variation of the variables in space and time which is very unrealistic for engineering problems and, in some cases, it leads to unacceptably inaccurate results. In the present work, linear and quadratic isoparametric boundary elements are used for discretization of geometry and functional variations in space. In addition, higher order variations in time are used. These methods of analysis are applicable to piecewise-homogeneous materials, such that not only problems of the layered media and the soil-structure interaction can be analyzed but also a large problem can be solved by the usual sub-structuring technique. The analyses have been incorporated in a versatile, general-purpose computer program. Some numerical problems are solved and, through comparisons

  19. Non-linear control of the ''clam'' wave energy device. Final report

    SciTech Connect

    Not Available

    1983-09-01

    A promising wave energy device being currently investigated is the ''clam'' device. The clam extracts energy by pumping air through a specially designed (Wells) turbine. Although operation of the Wells turbine does not require a rectified air flow, some additional control will be necessary to optimize the phase of the clam motion for good efficiencies. An examination of the equation of motion in the time domain suggests the possibility of non-linear phase control by mechanical, power take-off, or pneumatic latching. Latching can be shown to increase the efficiency of the device in the longer wavelengths of the wave spectrum, i.e. those of high incident wave power.

  20. The future of the Large Hadron Collider and CERN.

    PubMed

    Heuer, Rolf-Dieter

    2012-02-28

    This paper presents the Large Hadron Collider (LHC) and its current scientific programme and outlines options for high-energy colliders at the energy frontier for the years to come. The immediate plans include the exploitation of the LHC at its design luminosity and energy, as well as upgrades to the LHC and its injectors. This may be followed by a linear electron-positron collider, based on the technology being developed by the Compact Linear Collider and the International Linear Collider collaborations, or by a high-energy electron-proton machine. This contribution describes the past, present and future directions, all of which have a unique value to add to experimental particle physics, and concludes by outlining key messages for the way forward.

  1. High Resolution BPM for Linear Colliders

    SciTech Connect

    Simon, C.; Chel, S.; Luong, M.; Napoly, O.; Novo, J.; Roudier, D.; Rouviere, N.

    2006-11-20

    A high resolution Beam Position Monitor (BPM) is necessary for the beam-based alignment systems of high energy and low emittance electron linacs. Such a monitor is developed in the framework of the European CARE/SRF programme, in a close collaboration between DESY and CEA/DSM/DAPNIA. This monitor is a radiofrequency re-entrant cavity, which can be used either at room or cryogenic temperature, in an environment where dust particle contamination has to be avoided, such as superconducting cavities in a cryomodule. A first prototype of a re-entrant BPM has already delivered measurements at 2K. inside the first cryomodule (ACC1) on the TESLA Test Facility 2 (TTF2). The performances of this BPM are analyzed both experimentally and theoretically, and the limitations of this existing system clearly identified. A new cavity and new electronics have been designed in order to improve the position resolution down to 1 {mu}m and the damping time down to 10 ns.

  2. The International Linear Collider Progress Report 2015

    SciTech Connect

    Yamamoto, Akira

    2015-07-15

    The ILC technical design is now being adapted to the preferred candidate site. Changes in layout are being managed by a rigorous change-control procedure. Series production of cavities for the European XFEL has shown that cavities can be mass-produced in industry with a performance well above XFEL requirements and close to that needed for the ILC. A number of technical developments are under way with a view to further reducing the ILC cost. This work must continue through the preparatory stage for ILC construction once resources become available. A summary of the design updates and of the further preparatory work needed is summarized in tabular form in the Appendix.

  3. Injector for a laser linear collider

    NASA Astrophysics Data System (ADS)

    Mikhailichenko, A. A.

    1999-07-01

    The injector for 2×1 km long laser driven linac considered. Basically injector is a race track with long straight sections. These sections squeezed together for a compact size (a Kayak-Paddle like ring). In straight section the short period wigglers and RF cavities installed in series one by one for keeping the energy along the straight section practically constant. This injector is able to provide the invariant emittances of the order 5 10-8 cm rad and 2 10-9 cm rad for horizontal and vertical directions correspondingly. Bunch population required below 107 reduces the IBS effects.

  4. New approaches to linear and nonlinear programming. Final technical report, January 1, 1987--December 31, 1989

    SciTech Connect

    Murray, W.; Saunders, M.A.

    1990-03-01

    During the last twelve months, research has concentrated on barrier- function methods for linear programming (LP) and quadratic programming (QP). Some ground-work for the application of barrier methods to nonlinearly constrained problems has also begun. In our previous progress report we drew attention to the difficulty of developing robust implementations of barrier methods for LP. We have continued to refine both the primal algorithm and the dual algorithm. We still do not claim that the barrier algorithms are as robust as the simplex method; however, the dual algorithm has solved all the problems in our extensive test set. We have also gained some experience with using the algorithms to solve aircrew scheduling problems.

  5. Towards future circular colliders

    NASA Astrophysics Data System (ADS)

    Benedikt, Michael; Zimmermann, Frank

    2016-09-01

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

  6. Modeling Crabbing Dynamics in an Electron-Ion Collider

    SciTech Connect

    Castilla, Alejandro; Morozov, Vasiliy S.; Satogata, Todd J.; Delayen, Jean R.

    2015-09-01

    A local crabbing scheme requires π/2 (mod π) horizontal betatron phase advances from an interaction point (IP) to the crab cavities on each side of it. However, realistic phase advances generated by sets of quadrupoles, or Final Focusing Blocks (FFB), between the crab cavities located in the expanded beam regions and the IP differ slightly from π/2. To understand the effect of crabbing on the beam dynamics in this case, a simple model of the optics of the Medium Energy Electron-Ion Collider (MEIC) including local crabbing was developed using linear matrices and then studied numerically over multiple turns (1000 passes) of both electron and proton bunches. The same model was applied to both local and global crabbing schemes to determine the linear-order dynamical effects of the synchro-betatron coupling induced by crabbing.

  7. Non-linear chemistry of methane. Final report, December 1990-September 1993

    SciTech Connect

    Madronich, S.; Hess, P.; Fischer, C.

    1995-04-01

    The tropospheric chemistry of methane (CH4) is complex and depends non-linearly on emission fluxes of CH4 and other tropospheric constituents such as nitrogen oxides (NOx) and carbon monoxide (CO). Concern exists that increased CH4 emissions will reduce hydroxyl (OH) radicals (which determine the self-cleaning or oxidizing capacity of the troposphere) and increase the formation of noxious oxidants (especially ozone, O3). The authors have explored the steady-state solution phase space in a zero-dimensional model, and found four qualitatively different regimes: (1) for low CH4 and low NOx, OH is high and O3 is low; (2) for high CH4 and low NOx, OH is reduced while O3 is high; (3) for low CH4 and high NOx, both OH and O3 are suppressed; and (4) for high CH4 and high NOx, both OH and O3 levels are high. The high NOx solutions can exhibit multiple solutions and oscillations. The emission fluxes at which transitions occur from one regime to another were derived.

  8. Non-linear dynamic analysis of geared systems. Final Report Ph.D. Thesis

    NASA Technical Reports Server (NTRS)

    Singh, Rajendra; Houser, Donald R.; Kahraman, Ahmet

    1990-01-01

    Under driving conditions, a typical geared system may be subjected to large dynamic loads. Also, the vibration level of the geared system is directly related to the noise radiated from the gear box. The steady state dynamic behavior of the system is examined in order to design reliable and quiet transmissions. The scope is limited to a system containing a spur gear pair with backlash and periodically time varying mesh stiffness, and rolling element bearings with clearance type nonlinearities. The internal static transmission error at the gear mesh, which is of importance from high frequency noise and vibration control view point, is considered in the formulation in sinusoidal or periodic form. A dynamic finite element model of the linear time invariant (LTI) system is developed. Effects of several system parameters, such as torsional and transverse flexibilities of the shafts and prime mover/load inertias, on free and forced vibration characteristics are investigated. Several reduced order LTI models are developed and validated by comparing their eigen solutions with the finite element model results. Using the reduced order formulations, a three degree of freedom dynamic model is developed which includes nonlinearities associated with radical clearances in the radial rolling element bearings, backlash between a spur gear pair and periodically varying gear mesh stiffness. As a limiting case, a single degree of freedom model of the spur gear pair with backlash is considered and mathematical conditions for tooth separation and back collision are defined. Both digital simulation technique and analytical models such as method of harmonic balance and the method of multiple scales were used to develop the steady state frequency response characteristics for various nonlinear and/or time varying cases.

  9. Search for The Standard Model Higgs Boson in the four lepton final state by the D0 experiment at Run II of the Tevatron Collider

    SciTech Connect

    Menezes, Diego

    2013-01-01

    This dissertation presents a measurement of Z boson pair production in p¯p collisions at 1.96 TeV with 9.6 fb-1 to 9.8 fb-1 of D0 data. We examine the final states eeee, eeμμ, and μμμμ. Based on selected data, the measured cross section in the mass region M(Z/γ*) > 30 GeV is σ(p¯p → Z/γ* Z/γ*) = 1.26+0.44 -0.36 (stat)+0.17 -0.15 (syst) ± 0.08 (lumi) pb.

  10. DOE-HEP Final Report for 2013-2016: Studies of plasma wakefields for high repetition-rate plasma collider, and Theoretical study of laser-plasma proton and ion acceleration

    SciTech Connect

    Katsouleas, Thomas C.; Sahai, Aakash A.

    2016-08-08

    There were two goals for this funded project: 1. Studies of plasma wakefields for high repetition-rate plasma collider, and 2. Theoretical study of laser-plasma proton and ion acceleration. For goal 1, an analytical model was developed to determine the ion-motion resulting from the interaction of non-linear “blow-out” wakefields excited by beam-plasma and laser-plasma interactions. This is key to understanding the state of the plasma at timescales of 1 picosecond to a few 10s of picoseconds behind the driver-energy pulse. More information can be found in the document. For goal 2, we analytically and computationally analyzed the longitudinal instabilities of the laser-plasma interactions at the critical layer. Specifically, the process of “Doppler-shifted Ponderomotive bunching” is significant to eliminate the very high-energy spread and understand the importance of chirping the laser pulse frequency. We intend to publish the results of the mixing process in 2-D. We intend to publish Chirp-induced transparency. More information can be found in the document.

  11. Comparing Tsallis and Boltzmann temperatures from relativistic heavy ion collider and large hadron collider heavy-ion data

    NASA Astrophysics Data System (ADS)

    Gao, Y.-Q.; Liu, F.-H.

    2016-03-01

    The transverse momentum spectra of charged particles produced in Au + Au collisions at the relativistic heavy ion collider and in Pb + Pb collisions at the large hadron collider with different centrality intervals are described by the multisource thermal model which is based on different statistic distributions for a singular source. Each source in the present work is described by the Tsallis distribution and the Boltzmann distribution, respectively. Then, the interacting system is described by the (two-component) Tsallis distribution and the (two-component) Boltzmann distribution, respectively. The results calculated by the two distributions are in agreement with the experimental data of the Solenoidal Tracker At Relativistic heavy ion collider, Pioneering High Energy Nuclear Interaction eXperiment, and A Large Ion Collider Experiment Collaborations. The effective temperature parameters extracted from the two distributions on the descriptions of heavy-ion data at the relativistic heavy ion collider and large hadron collider are obtained to show a linear correlation.

  12. SUSY CP phases and asymmetries at colliders

    NASA Astrophysics Data System (ADS)

    Kittel, Olaf

    2009-06-01

    In the Minimal Supersymmetric Standard Model, physical phases of complex parameters lead to CP violation. We show how triple products of particle momenta or spins can be used to construct asymmetries, that allow us to probe these CP phases. To give specific examples, we discuss the production of neutralinos at the International Linear Collider (ILC). For the Large Hadron Collider (LHC), we discuss CP asymmetries in squark decays, and in the tri-lepton signal. We find that the CP asymmetries can be as large as 60%.

  13. 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.

  14. Environmental radiation effects from muon and tau colliders and their impact on facility licensing.

    PubMed

    Bevelacqua, J J

    2012-11-01

    Although contemporary accelerators only affect their local radiation environment, muon and tau colliders produce radiation profiles that extend far beyond their site boundaries. These radiation profiles affect the licensing and siting of these planned accelerators. The analysis presented herein suggests that a linear collider concept with the lepton beams collided in air offers a means to limit the environmental radiation effects from these accelerators.

  15. Status and future directions for advanced accelerator research-conventional and non-conventional collider concepts

    SciTech Connect

    Siemann, R.H.

    1997-03-01

    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 +}e{sup {minus}} linear colliders. {copyright} {ital 1997 American Institute of Physics.}

  16. The development of colliders

    SciTech Connect

    Sessler, A.M.

    1993-02-01

    Don Kerst, Gersh Budker, and Bruno Touschek were the individuals, and the motivating force, which brought about the development of colliders, while the laboratories at which it happened were Stanford, MURA, the Cambridge Electron Accelerator, Orsay, Frascati, CERN, and Novosibirsk. These laboratories supported, during many years, this rather speculative activity. Of course, many hundreds of physicists contributed to the development of colliders but the men who started it, set it in the right direction, and forcefully made it happen, were Don, Gersh, and Bruno. Don was instrumental in the development of proton-proton colliders, while Bruno and Gersh spearheaded the development of electron-positron colliders. In this brief review of the history, I will sketch the development of the concepts, the experiments, and the technological developments which made possible the development of colliders. It may look as if the emphasis is on theoretical concepts, but that is really not the case, for in this field -- the physics of beams -- the theory and experiment go hand in hand; theoretical understanding and advances are almost always motivated by the need to explain experimental results or the desire to construct better experimental devices.

  17. The Muon Collider

    SciTech Connect

    Zisman, Michael S

    2010-05-17

    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. 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.

  19. 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.

  20. 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.

  1. High energy colliders

    SciTech Connect

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

    1997-02-01

    The authors consider the high energy physics advantages, disadvantages and luminosity requirements of hadron (pp, p{anti p}), lepton (e{sup +}e{sup {minus}}, {mu}{sup +}{mu}{sup {minus}}) and photon-photon colliders. Technical problems in obtaining increased energy in each type of machine are presented. The machines relative size are also discussed.

  2. High luminosity particle colliders

    SciTech Connect

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

    1997-03-01

    The authors consider the high energy physics advantages, disadvantages and luminosity requirements of hadron (pp, p{anti p}), lepton (e{sup +}e{sup {minus}}, {mu}{sup +}{mu}{sup {minus}}) and photon-photon colliders. Technical problems in obtaining increased energy in each type of machine are presented. The machines relative size are also discussed.

  3. 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.

  4. Accelarators, Colliders and Their Application

    NASA Astrophysics Data System (ADS)

    Wilson, E.

    This document is part of Subvolume C 'Accelerators and Colliders' of Volume 21 'Elementary Particles' of Landolt-Börnstein - Group I 'Elementary Particles, Nuclei and Atoms'. It contains the Chapter '1 Accelarators, Colliders and Their Application' with the content:

  5. The SLAC linac as used in the SLC collider

    SciTech Connect

    Seeman, J.T.; Abrams, G.; Adolphsen, C.; Atwood, W.; Bane, K.L.F.; Iverson, R.; Jacobsen, R.; Himel, T.M.; Jobe, R.K.; Lavine, T.L.

    1989-06-01

    The linac of the SLAC Linear Collider (SLC) must accelerate three high intensity bunches on each linac pulse from 1.2 GeV to 50 GeV with minimal increase of the small transverse emittance. The procedures and adjustments used to obtain this goal are outlined. Some of the accelerator parameters and components which interact are the beam energy, transverse position, component alignment, RF manipulation, feedback systems, quadrupole lattice, BNS damping, energy spectra, phase space matching, collimation, instrumentation and modelling. The method to bring these interdependent parameters collectively into specification has evolved over several years. This review is ordered in the sequence which is used to turn on the linac from a cold start and produce acceptable beams for the final focus and collisions. Approximate time estimates for the various activities are given. 21 refs.

  6. Influence of Magnet Multipole Field Components on Beam Dynamics in the JLEIC Ion Collider Ring

    SciTech Connect

    Wei, Guohui; Morozov, Vasiliy; Lin, Fanglei; Zhang, Yuhong; Pilat, Fulvia C.; Wang, Min-Huey

    2016-05-01

    To get a luminosity level of a few 1033 cm-2ses₋1 at all design points of the Jefferson Lab Electron Ion Collider (JLEIC) project, small β* values in both horizontal and vertical planes are necessary at the Interaction Point (IP) in the ion collider ring. This also means large β in the final focus area, chromaticity correction sections, etc. which sets a constraint on the field quality of magnets in large beta areas, in order to ensure a large enough dynamic aperture (DA). In this context, limiting multipole field components of magnets are surveyed to find a possible compromise between the requirements and what can be realistically achieved by a magnet manufacturer. This paper describes that work. Moreover, non-linear field dedicated correctors are also studied to provide semi-local corrections of specific multipole field components.

  7. Accelerators, Colliders, and Snakes

    NASA Astrophysics Data System (ADS)

    Courant, Ernest D.

    2003-12-01

    The author traces his involvement in the evolution of particle accelerators over the past 50 years. He participated in building the first billion-volt accelerator, the Brookhaven Cosmotron, which led to the introduction of the "strong-focusing" method that has in turn led to the very large accelerators and colliders of the present day. The problems of acceleration of spin-polarized protons are also addressed, with discussions of depolarizing resonances and "Siberian snakes" as a technique for mitigating these resonances.

  8. 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.

  9. Heavy Meson Production at a Low-Energy Photon Collider

    SciTech Connect

    Asztalos, S

    2004-04-15

    A low-energy {gamma}{gamma} collider has been discussed in the context of a testbed for a {gamma}{gamma} interaction region at the Next Linear Collider(NLC). We consider the production of heavy mesons at such a testbed using Compton-backscattered photons and demonstrate that their production rivals or exceeds those by BELLE, BABAR or LEP where they are produced indirectly via virtual {gamma}{gamma} luminosities.

  10. Diffractive ρ production at small x in future electron-ion colliders

    NASA Astrophysics Data System (ADS)

    Gonçalves, V. P.; Navarra, F. S.; Spiering, D.

    2016-09-01

    The future electron-ion (eA) collider is expected to probe the high energy regime of the quantum chromodynamics (QCD), with the exclusive vector meson production cross section being one of the most promising observables. In this paper we complement previous studies of exclusive processes presenting a comprehensive analysis of diffractive ρ production at small x. We compute the coherent and incoherent cross sections taking into account non-linear QCD dynamical effects and considering different models for the dipole-proton scattering amplitude and vector meson wave function. The dependence of these cross sections on the energy, photon virtuality, nuclear mass number and squared momentum transfer is analysed in detail. Moreover, we compare the non-linear predictions with those obtained in the linear regime. Finally, we also estimate the exclusive photon, J/{{\\Psi }} and ϕ production and compare with the results obtained for ρ production. Our results demonstrate that the analysis of diffractive ρ production in future electron-ion colliders will be important in understanding the non-linear QCD dynamics.

  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. Physics at a photon collider

    SciTech Connect

    Stefan Soldner-Rembold

    2002-09-30

    A Photon Collider will provide unique opportunities to study the SM Higgs boson and to determine its properties. MSSM Higgs bosons can be discovered at the Photon Collider for scenarios where they might escape detection at the LHC. As an example for the many other physics topics which can be studied at a Photon Collider, recent results on Non-Commutative Field Theories are also discussed.

  13. 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.

  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. DOE Final Report -NON-LINEAR WAVES IN CONTINUOUS MEDIA- BES- Division of Engineering and Materials Science

    SciTech Connect

    Seth J. Putterman

    2006-01-10

    FINAL REPORT ON : NON-LINEAR WAVES IN CONTINUOUS MEDIA Doe DE FG03-87ER13686 (001312-001) Submitted January 10, 2006 by Seth J. Putterman 310-8252269 Physics Department University of California Los Angeles, CA 90095 puherman@ritva.physics.ucla.edu NON-LINEAR WAVES IN CONTINUOUS MEDIA I am happy to report that this project has been a big success. For over 10 years the DOE [Division of Materials Sciences and Engineering] has funded our research program on the overarching theme of spontaneous energy focusing phenomena. These effects occur when a nonlinear macroscopic system is excited so as to drive it far from equilibrium. The subsequent relaxation to equilibrium does not occur smoothly but instead is accompanied by the formation of structured domains where the energy density is highly concentrated. A signature example is picosecond sonoluminescence [1] wherein a smooth sound wave has its energy density focused by 12 orders of magnitude to generate a clock-like string of picosecond flashes of ultraviolet light. Our earlier work on solitons [2] demonstrated how uniform surface waves break up into stable localized structures. Our experimental work on turbulence produced photos of localized structures lying many standard deviations outside the range of gaussian statistics[3]. This effect is referred to as intermittency. Our recent work on friction finds its motivation in those theories of sonoluminescence which invoke frictional electricity. In its most common form this is the generation of a spark when we touch a doorknob after walking over a carpet. Our reading of the literature on this subject indicated that frictional electricity like sonoluminescence is not understood. So to probe triboelectrification we set up a modern version of an experiment performed by Bernoulli in 1700. Here sparking is caused by the rubbing of glass against mercury. We indeed observed flashes of light which were accompanied by events of stick-slip friction at the interface between the

  16. 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.

  17. Soviet Hadron Collider

    NASA Astrophysics Data System (ADS)

    Kotchetkov, Dmitri

    2017-01-01

    Rapid growth of the high energy physics program in the USSR during 1960s-1970s culminated with a decision to build the Accelerating and Storage Complex (UNK) to carry out fixed target and colliding beam experiments. The UNK was to have three rings. One ring was to be built with conventional magnets to accelerate protons up to the energy of 600 GeV. The other two rings were to be made from superconducting magnets, each ring was supposed to accelerate protons up to the energy of 3 TeV. The accelerating rings were to be placed in an underground tunnel with a circumference of 21 km. As a 3 x 3 TeV collider, the UNK would make proton-proton collisions with a luminosity of 4 x 1034 cm-1s-1. Institute for High Energy Physics in Protvino was a project leading institution and a site of the UNK. Accelerator and detector research and development studies were commenced in the second half of 1970s. State Committee for Utilization of Atomic Energy of the USSR approved the project in 1980, and the construction of the UNK started in 1983. Political turmoil in the Soviet Union during late 1980s and early 1990s resulted in disintegration of the USSR and subsequent collapse of the Russian economy. As a result of drastic reduction of funding for the UNK, in 1993 the project was restructured to be a 600 GeV fixed target accelerator only. While the ring tunnel and proton injection line were completed by 1995, and 70% of all magnets and associated accelerator equipment were fabricated, lack of Russian federal funding for high energy physics halted the project at the end of 1990s.

  18. Nonglobal correlations in collider physics

    DOE PAGES

    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

  19. Nonglobal correlations in collider physics

    SciTech Connect

    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 it 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.

  20. 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.

  1. MPO B593110 - Final Report

    SciTech Connect

    Brooksby, C

    2011-07-25

    National Security Technologies, LLC (NSTec) shall provide one (1) Mechanical Engineer to support the Linear Collider Subsystem Development Program at Lawrence Livermore National Security, LLC (LLNS). The NSTec Mechanical Engineer's efforts will include engineering, design, and drawing support for the Vacuum Seal Test. NSTec will also provide a final report of the setup and input to LLNL's project management on project status. The NSTec Mechanical Engineer's efforts will also include engineering, design, and drawing support to the conceptual design for manufacturing of the Flux Concentrator Magnet. NSTec will also contribute to LLNS's final report on the Flux Concentrator Magnet. The deliverables are drawings, sketches, engineering documents, and final reports delivered to the LLNS Technical Representative.

  2. Environmental and human safety of major surfactants. Volume 1. Anionic surfactants. Part 1. Linear alkylbenzene sulfonates. Final report

    SciTech Connect

    Not Available

    1991-02-01

    The report discusses critical reviews of published literature and unpublished company data on major surfactants. Part 1 of Vol. 1 discusses the chemistry, biodegradation, environmental effects and safety and human safety of linear alkylbenzene sulfonates. The information presented updates and supplements similar data included in two predecessor studies, Human Safety and Environmental Aspects of Major Surfactants (1977) NTIS Accession Number PB-301193 and Human and Environmental Aspects of Major Surfactants (Supplement) (1981) NTIS Accession Number PB-81-182453.

  3. Crystal Ball: On the Future High Energy Colliders

    SciTech Connect

    Shiltsev, Vladimir

    2015-09-20

    High energy particle colliders have been in the forefront of particle physics for more than three decades. At present the near term US, European and international strategies of the particle physics community are centered on full exploitation of the physics potential of the Large Hadron Collider (LHC) through its high-luminosity upgrade (HL-LHC). A number of next generation collider facilities have been proposed and are currently under consideration for the medium- and far-future of the accelerator-based high energy physics. In this paper we offer a uniform approach to evaluation of various accelerators based on the feasibility of their energy reach, performance reach and cost range. We briefly review such post-LHC options as linear e+e- colliders in Japan (ILC) or at CERN (CLIC), muon collider, and circular lepton or hadron colliders in China (CepC/SppC) and Europe (FCC). We conclude with a look into ultimate energy reach accelerators based on plasmas and crystals, and some perspectives for the far future of accelerator-based particle physics.

  4. 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.

  5. Physics at future hadron colliders

    SciTech Connect

    U. Baur et al.

    2002-12-23

    We discuss the physics opportunities and detector challenges at future hadron colliders. As guidelines for energies and luminosities we use the proposed luminosity and/or energy upgrade of the LHC (SLHC), and the Fermilab design of a Very Large Hadron Collider (VLHC). We illustrate the physics capabilities of future hadron colliders for a variety of new physics scenarios (supersymmetry, strong electroweak symmetry breaking, new gauge bosons, compositeness and extra dimensions). We also investigate the prospects of doing precision Higgs physics studies at such a machine, and list selected Standard Model physics rates.

  6. Advanced Concepts for Electron-Ion Collider

    SciTech Connect

    Yaroslav Derbenev

    2002-08-01

    A superconducting energy recovery linac (ERL) of 5 to 10 GeV was proposed earlier as an alternative to electron storage rings to deliver polarized electron beam for electron-ion collider (EIC). To enhance the utilization efficiency of electron beam from a polarized source, it is proposed to complement the ERL by circulator ring (CR) wherein the injected electrons undergo up to 100 revolutions colliding with the ion beam. In this way, electron injector and linac operate in pulsed current (beam energy recovery) regime of a relatively low average current, while the polarization is still easily delivered and preserved. To make it also easier delivering and manipulating the proton and light ion polarization, twisted (figure 8) synchrotrons are proposed for heavy particle booster and collider ring. Same type of beam orbit can be used then for electron circulator. Electron cooling (EC) of the ion beam is considered an inevitable component of high luminosity EIC (1033/s. cm2 or above). It is recognized that EC also gives a possibility to obtain very short ion bunches, that allows much stronger final focusing. At the same time, short bunches make feasible the crab crossing (and traveling focus for ion beam) at collision points, hence, allow maximizing the collision rate. As a result, one can anticipate the luminosity increase by one or two orders of magnitude.

  7. Design considerations for the semi-digital hadronic calorimeter (SDHCAL) for future leptonic colliders

    NASA Astrophysics Data System (ADS)

    Pingault, A.

    2016-07-01

    The first technological SDHCAL prototype having been successfully tested, a new phase of R&D, to validate completely the SDHCAL option for the International Linear Detector (ILD) project of the International Linear Collider (ILC), has started with the conception and the realisation of a new prototype. The new one is intended to host few but large active layers of the future SDHCAL. The new active layers, made of Glass Resistive Plate Chambers (GRPC) with sizes larger than 2 m2 will be equipped with a new version of the electronic readout, fulfilling the requirements of the future ILD detector. The new GRPC are conceived to improve the homogeneity with a new gas distribution scheme. Finally the mechanical structure will be achieved using the electron beam welding technique. The progress realised will be presented and future steps will be discussed.

  8. Signatures of extra gauge bosons in the littlest Higgs model with T parity at future colliders

    SciTech Connect

    Cao, Qing-Hong; Chen, Chuan-Ren

    2007-10-01

    We study the collider signatures of a T-odd gauge boson W{sub H} pair production in the littlest Higgs model with T parity (LHT) at Large Hadron Collider (LHC) and Linear Collider (LC). At the LHC, we search for the W{sub H} boson using its leptonic decay, i.e. pp{yields}W{sub H}{sup +}W{sub H}{sup -}{yields}A{sub H}A{sub H}l{sup +}{nu}{sub l}l{sup '-}{nu}{sub l{sup '}}, which gives rise to a collider signature of l{sup +}l{sup '-}+Ee{sub T}. We demonstrate that the LHC not only has a great potential of discovering the W{sub H} boson in this channel, but also can probe enormous parameter space of the LHT. Because of four missing particles in the final state, one cannot reconstruct the mass of W{sub H} at the LHC. But such a mass measurement can be easily achieved at the LC in the process of e{sup +}e{sup -}{yields}W{sub H}{sup +}W{sub H}{sup -}{yields}A{sub H}A{sub H}W{sup +}W{sup -}{yields}A{sub H}A{sub H}jjjj. We present an algorithm of measuring the mass and spin of the W{sub H} boson at the LC. Furthermore, we illustrate that the spin correlation between the W boson and its mother particle (W{sub H}) can be used to distinguish the LHT from other new physics models.

  9. 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.

  10. QCD at collider energies

    NASA Astrophysics Data System (ADS)

    Nicolaidis, A.; Bordes, G.

    1986-05-01

    We examine available experimental distributions of transverse energy and transverse momentum, obtained at the CERN pp¯ collider, in the context of quantum chromodynamics. We consider the following. (i) The hadronic transverse energy released during W+/- production. This hadronic transverse energy is made out of two components: a soft component which we parametrize using minimum-bias events and a semihard component which we calculate from QCD. (ii) The transverse momentum of the produced W+/-. If the transverse momentum (or the transverse energy) results from a single gluon jet we use the formalism of Dokshitzer, Dyakonov, and Troyan, while if it results from multiple-gluon emission we use the formalism of Parisi and Petronzio. (iii) The relative transverse momentum of jets. While for W+/- production quarks play an essential role, jet production at moderate pT and present energies is dominated by gluon-gluon scattering and therefore we can study the Sudakov form factor of the gluon. We suggest also how through a Hankel transform of experimental data we can have direct access to the Sudakov form factors of quarks and gluons.

  11. Alternative positron-target design for electron-positron colliders

    SciTech Connect

    Donahue, R.J. ); Nelson, W.R. )

    1991-04-01

    Current electron-positron linear colliders are limited in luminosity by the number of positrons which can be generated from targets presently used. This paper examines the possibility of using an alternate wire-target geometry for the production of positrons via an electron-induced electromagnetic cascade shower. 39 refs., 38 figs., 5 tabs.

  12. The chromatic correction in RHIC (Relativistic Heavy Ion Collider)

    SciTech Connect

    Lee, S.Y.; Dell, G.F.; Hahn, H.; Parzen, G.

    1987-01-01

    The scheme for the correction of chromatic effects in the Relativistic Heavy Ion Collider at BNL is discussed. This scheme uses six families of sextupoles excited by four independent power supplies, and provides adequate control of linear and quadratic terms in the tune vs momentum dependence and reduces the variation of the betatron amplitude, vs momentum.

  13. 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.

  14. 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).

  15. 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.

  16. Single and multiple intrabeam scattering in hadron colliders

    SciTech Connect

    Lebedev, V.; /Fermilab

    2005-01-01

    Single and multiple intra-beam scattering are usually considered separately. Such separation works well for electron-positron colliders but usually yields only coarse description in the case of hadron colliders. Boltzmann type integro-differential equation is used to describe evolution of longitudinal distribution due to IBS. The finite size of the longitudinal potential well, its non-linearity and x-y coupling are taken into account. The model predictions for longitudinal and transverse distributions are compared to the experimental measurements.

  17. High Energy Colliders as Tools to Understand the Early Universe

    SciTech Connect

    Tait, Tim

    2008-08-16

    Cosmological observations have reached a new era of precision, and reveal many interesting and puzzling features of the Universe. I will briefly review two of the most exciting mysteries: the nature of the dark components of the Universe, and the origin of the asymmetry between matter and anti-matter. I will argue that our best hope of unraveling these questions will need to combine information from the heavens with measurements in the lab at high energy particle accelerators. The end of run II of the Tevatron, the up-coming Large Hadron Collider and proposed International Linear Collider all have great potential to help us answer these questions in the near future.

  18. Modelling the Fermilab Collider to determine optimal running

    SciTech Connect

    McCrory, E.

    1994-12-01

    A Monte Carlo-type model of the Fermilab Collider has been constructed, the goal of which is to accurately represent the operation of the Collider, incorporating the aspects of the facility which affect operations in order to determine how to run optimally. In particular, downtime for the various parts of the complex are parameterized and included. Also, transfer efficiencies, emittance growths, changes in the luminosity lifetime and other effects are included and randomized in a reasonable manner. This Memo is an outgrowth of TM-1878, which presented an entirely analytical model of the Collider. It produced a framework for developing intuition on the way in which the major components of the collider affect the luminosity, like the stacking rate and the shot set-up time, for example. However, without accurately including downtime effects, it is not possible to say with certainty that the analytical approach can produce accurate guidelines for optimizing the performance of the Collider. This is the goal of this analysis. We first discuss the way the model is written, describing the object-oriented approach taken in C++. The parameters of the simulation are described. Then the potential criteria for ending stores are described and analyzed. Next, a typical store and a typical week are derived. Then, a final conclusion on the best end-of-store criterion is made. Finally, ideas for future analysis are presented.

  19. Final Environmental Assessment for the construction and operation of an office building at the Stanford Linear Accelerator Center. Part 2

    SciTech Connect

    1995-08-01

    The Department of Energy (DOE) has prepared an Environmental Assessment (EA), DOE/EA-1107, analyzing the environmental effects relating to the construction and operation of an office building at the Stanford Linear Accelerator Center (SLAC). SLAC is a national facility operated by Stanford University, California, under contract with DOE. The center is dedicated to research in elementary particle physics and in those fields that make use of its synchrotron facilities. The objective for the construction and operation of an office building is to provide adequate office space for existing SLAC Waste Management (WM) personnel, so as to centralize WM personnel and to make WM operations more efficient and effective. Based on the analyses in the EA, the DOE has determined that the proposed action does not constitute a major Federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (NEPA). Therefore, the preparation of an Environmental Impact Statement is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI).

  20. Detectors for the superconducting super collider, design concepts, and simulation

    SciTech Connect

    Gabriel, T.A.

    1989-06-01

    The physics of compensation calorimetry is reviewed in the light of the needs of the Superconducting Super Collider (SSC) detectors. The four major detector types: liquid argon, scintillator, room temperature liquids, and silicon, are analyzed with respect to some of their strengths and weaknesses. Finally, general comments are presented which reflect the reliability of simulation code systems.

  1. Prospects for collider searches for dark matter with heavy quarks

    SciTech Connect

    Artoni, Giacomo; Lin, Tongyan; Penning, Bjoern; Sciolla, Gabriella; Venturini, Alessio

    2013-08-05

    We present projections for future collider searches for dark matter produced in association with bottom or top quarks. Such production channels give rise to final states with missing transverse energy and one or more b-jets. Limits are given assuming an effective scalar operator coupling dark matter to quarks, where the dedicated analysis discussed here improves significantly over a generic monojet analysis. We give updated results for an anticipated high-luminosity LHC run at 14 TeV and for a 33 TeV hadron collider.

  2. NEUTRINO RADIATION CHALLENGES AND PROPOSED SOLUTIONS FOR MANY-TEV MUON COLLIDERS

    SciTech Connect

    KING,B.J.

    2000-05-05

    Neutrino radiation is expected to impose major design and siting constraints on many-TeV muon colliders. Previous predictions for radiation doses at TeV energy scales are briefly reviewed and then modified for extension to the many-TeV energy regime. The energy-cubed dependence of lower energy colliders is found to soften to an increase of slightly less than quadratic when averaged over the plane of the collider ring and slightly less than linear for the radiation hot spots downstream from straight sections in the collider ring. Despite this, the numerical values are judged to be sufficiently high that any many-TeV muon colliders will likely be constructed on large isolated sites specifically chosen to minimize or eliminate human exposure to the neutrino radiation. It is pointed out that such sites would be of an appropriate size scale to also house future proton-proton and electron-positron colliders at the high energy frontier, which naturally leads to conjecture on the possibilities for a new world laboratory for high energy physics. Radiation dose predictions are also presented for the speculative possibility of linear muon colliders. These have greatly reduced radiation constraints relative to circular muon colliders because radiation is only emitted in two pencil beams directed along the axes of the opposing linacs.

  3. 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.

  4. Recent results from hadron colliders

    SciTech Connect

    Frisch, H.J. )

    1990-12-10

    This is a summary of some of the many recent results from the CERN and Fermilab colliders, presented for an audience of nuclear, medium-energy, and elementary particle physicists. The topics are jets and QCD at very high energies, precision measurements of electroweak parameters, the remarkably heavy top quark, and new results on the detection of the large flux of B mesons produced at these machines. A summary and some comments on the bright prospects for the future of hadron colliders conclude the talk. 39 refs., 44 figs., 3 tabs.

  5. 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.

  6. Symmetric Achromatic Low-Beta Collider Interaction Region Design Concept

    SciTech Connect

    Morozov, Vasiliy S.; Derbenev, Yaroslav S.; Lin, Fanglei; Johnson, Rolland P.

    2013-01-01

    We present a new symmetry-based concept for an achromatic low-beta collider interaction region design. A specially-designed symmetric Chromaticity Compensation Block (CCB) induces an angle spread in the passing beam such that it cancels the chromatic kick of the final focusing quadrupoles. Two such CCB?s placed symmetrically around an interaction point allow simultaneous compensation of the 1st-order chromaticities and chromatic beam smear at the IP without inducing significant 2nd-order aberrations. We first develop an analytic description of this approach and explicitly formulate 2nd-order aberration compensation conditions at the interaction point. The concept is next applied to develop an interaction region design for the ion collider ring of an electron-ion collider. We numerically evaluate performance of the design in terms of momentum acceptance and dynamic aperture. The advantages of the new concept are illustrated by comparing it to the conventional distributed-sextupole chromaticity compensation scheme.

  7. Muon-muon and other high energy colliders

    SciTech Connect

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

    1997-02-01

    The first section looks at the high energy physics advantages, disadvantages and luminosity requirements of hadron, of lepton and photon-photon colliders for comparison. The second section discusses the physics considerations for the muon collider. The third section covers muon collider components. The fourth section is about the intersection region and detectors. In the fifth section, the authors discuss modifications to enhance the muon polarization`s operating parameters with very small momentum spreads, operations at energies other than the maximum for which the machine is designed, and designs of machines for different maximum energies. The final section discusses a Research and Development plan aimed at the operation of a 0.5 TeV demonstration machine by the year 2010, and of the 4 TeV machine by the year 2020.

  8. Design of a 6 TeV muon collider

    SciTech Connect

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

    2015-05-19

    A design of a muon collider ring with the center of mass energy of 6 TeV is presented. The ring circumference is about 6.3 km, and the beta functions at collision point are 1 cm in both planes. The ring linear optics, the non-linear chromaticity correction scheme in the Interaction Region (IR), and the additional non-linear field orthogonal knobs are described. The IR magnet specifications are based on the maximum pole tip field of 20 T in dipoles and 15 T in quadrupoles. The results of the beam dynamics optimization for maximum dynamic aperture are presented.

  9. Design of a 6 TeV Muon Collider

    SciTech Connect

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

    2015-06-01

    A design of a muon collider ring with the center of mass energy of 6 TeV is presented. The ring circumference is about 6.3 km, and the $\\beta$ functions at collision point are 1 cm in both planes. The ring linear optics, the non-linear chromaticity correction scheme in the Interaction Region (IR), and the additional non-linear field orthogonal knobs are described. The IR magnet specifications are based on the maximum pole tip field of 20 T in dipoles and 15 T in quadrupoles. The results of the beam dynamics optimization for maximum dynamic aperture are presented.

  10. e+ e- collider in the VLHC tunnel. Proceedings, Workshop, Chicago, USA, March 9-11, 2001

    SciTech Connect

    Dugan, D.,; Tollestrup, A.,; /Fermilab

    2001-07-01

    This document is a collection of the contributions made to the March IIT workshop on an e{sup +}e{sup -} collider in the VLHC tunnel. This machine, which is based on a relatively conservative extrapolation of LEP technology, has a baseline luminosity of 10{sup 33}/cm{sup 2}/s at a CM energy of 370 GeV. The overall parameters and general description of such a machine is described in T. Sen and J. Norem, ''A Very Large Lepton Collider in the VLHC Tunnel'', to be published. A preprint of this paper is included as Appendix 2 of this report. The intention of the workshop was to define the parameters of such a collider and make them available to the community for use in further physics studies. It is clear that the machine cannot compete with a full scale linear collider. Its main interest would be if a VLHC were built and if a linear collider did not already exist. In this case, it could provide a limited and perhaps crucial view of low mass Higgs states. Although the study is incomplete, it does define rather well the parameters of the machine, as well as the challenges that the design faces. The study benefited greatly from the participation of the machine experts that were willing to spend time looking at the design. In this document, the workshop contributions are organized into sections which cover the physics motivation for the machine; the injector; beam dynamics issues in the collider; and accelerator systems. The physics section describes luminosity benchmarks for study of a light Higgs boson, and machine performance issues related to lineshape measurements at the t{bar t} threshold. The contribution on the injector presents a design for a 45 GeV injector. The injection energy is motivated by two considerations: the collider has potential stability problems at injection, which are mitigated by a relatively high injection energy; and, at this energy, the injector can also serve as a Z{sup 0} factory. One of the principal conclusions of the IIT workshop was that

  11. Muon Colliders: The Next Frontier

    ScienceCinema

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

    2016-07-12

    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.

  12. 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.

  13. 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.

  14. 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.

  15. 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.

  16. VINCIA for hadron colliders

    NASA Astrophysics Data System (ADS)

    Fischer, N.; Prestel, S.; Ritzmann, M.; Skands, P.

    2016-11-01

    We present the first public implementation of antenna-based QCD initial- and final-state showers. The shower kernels are 2→ 3 antenna functions, which capture not only the collinear dynamics but also the leading soft (coherent) singularities of QCD matrix elements. We define the evolution measure to be inversely proportional to the leading poles, hence gluon emissions are evolved in a p_perp measure inversely proportional to the eikonal, while processes that only contain a single pole (e.g., g→ qbar{q}) are evolved in virtuality. Non-ordered emissions are allowed, suppressed by an additional power of 1/Q^2. Recoils and kinematics are governed by exact on-shell 2→ 3 phase-space factorisations. This first implementation is limited to massless QCD partons and colourless resonances. Tree-level matrix-element corrections are included for QCD up to O(α _s^4) (4 jets), and for Drell-Yan and Higgs production up to O(α _s^3) ( V / H + 3 jets). The resulting algorithm has been made publicly available in Vincia 2.0.

  17. Shedding Light on Dark Matter at Colliders

    NASA Astrophysics Data System (ADS)

    Mitsou, Vasiliki A.

    2013-12-01

    Dark matter remains one of the most puzzling mysteries in Fundamental Physics of our times. Experiments at high-energy physics colliders are expected to shed light to its nature and determine its properties. This review focuses on recent searches for dark matter signatures at the Large Hadron Collider, also discussing related prospects in future e+e- colliders.

  18. 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

  19. 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.

  20. Detectors for Linear Colliders: Detector design for a Future Electron-Positron Collider (4/4)

    ScienceCinema

    None

    2016-07-12

    In this lecture I will discuss the issues related to the overall design and optimization of a detector for ILC and CLIC energies. I will concentrate on the two main detector concepts which are being developed in the context of the ILC. Here there has been much recent progress in developing realistic detector models and in understanding the physics performance of the overall detector concept. In addition, I will discuss the how the differences in the detector requirements for the ILC and CLIC impact the overall detector design.

  1. High energy particle colliders: past 20 years, next 20 years and beyond

    SciTech Connect

    Shiltsev, Vladimir D.; /Fermilab

    2012-04-01

    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 method and the history of colliders, discuss in detail the developments over the past two decades and the directions of the R and D toward near future colliders which are currently being explored. Finally, we make an attempt to look beyond the current horizon and outline the changes in the paradigm required for the next breakthroughs.

  2. Polarized proton collider at RHIC

    NASA Astrophysics Data System (ADS)

    Alekseev, I.; Allgower, C.; Bai, M.; Batygin, Y.; Bozano, L.; Brown, K.; Bunce, G.; Cameron, P.; Courant, E.; Erin, S.; Escallier, J.; Fischer, W.; Gupta, R.; Hatanaka, K.; Huang, H.; Imai, K.; Ishihara, M.; Jain, A.; Lehrach, A.; Kanavets, V.; Katayama, T.; Kawaguchi, T.; Kelly, E.; Kurita, K.; Lee, S. Y.; Luccio, A.; MacKay, W. W.; Mahler, G.; Makdisi, Y.; Mariam, F.; McGahern, W.; Morgan, G.; Muratore, J.; Okamura, M.; Peggs, S.; Pilat, F.; Ptitsin, V.; Ratner, L.; Roser, T.; Saito, N.; Satoh, H.; Shatunov, Y.; Spinka, H.; Syphers, M.; Tepikian, S.; Tominaka, T.; Tsoupas, N.; Underwood, D.; Vasiliev, A.; Wanderer, P.; Willen, E.; Wu, H.; Yokosawa, A.; Zelenski, A. N.

    2003-03-01

    In addition to heavy ion collisions (RHIC Design Manual, Brookhaven National Laboratory), RHIC will also collide intense beams of polarized protons (I. Alekseev, et al., Design Manual Polarized Proton Collider at RHIC, Brookhaven National Laboratory, 1998 [2]), reaching transverse energies where the protons scatter as beams of polarized quarks and gluons. The study of high energy polarized protons beams has been a long term part of the program at BNL with the development of polarized beams in the Booster and AGS rings for fixed target experiments. We have extended this capability to the RHIC machine. In this paper we describe the design and methods for achieving collisions of both longitudinal and transverse polarized protons in RHIC at energies up to s=500 GeV.

  3. ep Collider experiments and physics

    SciTech Connect

    Atwood, D.; Baur, U.; Bluemlein, J.

    1992-12-31

    The physics prospects for detectors at ep colliders are examined. Colliders considered include the HERA facility at DESY, LEP I {times} LHC, and LEP II {times} LHC at CERN. Physics topics studied include machine energy and polarization, as well as detector resolution, calibration, jet identification and backgrounds from beam-gas interactions. QCD topics include measurements of the quark and gluon structure functions and parton distributions, as well as the expansion of the observable cross section into angular functions. Electroweak topics include measurements of the weak mixing angle, radiative corrections, and WW{gamma} (WWZ) couplings. Topics beyond the standard model include observation of new Z`s, indirect production of Leptoquarks, pair production of sfermions and searches for R-parity-violating SUSY particle production.

  4. Luminosity limitations for Electron-Ion Collider

    SciTech Connect

    Valeri Lebedev

    2000-09-01

    The major limitations on reaching the maximum luminosity for an electron ion collider are discussed in application to the ring-ring and linac-ring colliders. It is shown that with intensive electron cooling the luminosity of 10{sup 33} cm{sup -2} s{sup -1} is feasible for both schemes for the center-of-mass collider energy above approximately 15 GeV. Each scheme has its own pros and cons. The ring-ring collider is better supported by the current accelerator technology while the linac-ring collider suggests unique features for spin manipulations of the electron beam. The article addresses a general approach to a choice of collider scheme and parameters leaving details for other conference publications dedicated to particular aspects of the ring-ring and linac-ring colliders.

  5. International Linear Collider Accelerator Physics R&D

    SciTech Connect

    George D. Gollin; Michael Davidsaver; Michael J. Haney; Michael Kasten; Jason Chang; Perry Chodash; Will Dluger; Alex Lang; Yehan Liu

    2008-09-03

    ILC work at Illinois has concentrated primarily on technical issues relating to the design of the accelerator. Because many of the problems to be resolved require a working knowledge of classical mechanics and electrodynamics, most of our research projects lend themselves well to the participation of undergraduate research assistants. The undergraduates in the group are scientists, not technicians, and find solutions to problems that, for example, have stumped PhD-level staff elsewhere. The ILC Reference Design Report calls for 6.7 km circumference damping rings (which prepare the beams for focusing) using “conventional” stripline kickers driven by fast HV pulsers. Our primary goal was to determine the suitability of the 16 MeV electron beam in the AØ region at Fermilab for precision kicker studies.We found that the low beam energy and lack of redundancy in the beam position monitor system complicated the analysis of our data. In spite of these issues we concluded that the precision we could obtain was adequate to measure the performance and stability of a production module of an ILC kicker, namely 0.5%. We concluded that the kicker was stable to an accuracy of ~2.0% and that we could measure this precision to an accuracy of ~0.5%. As a result, a low energy beam like that at AØ could be used as a rapid-turnaround facility for testing ILC production kicker modules. The ILC timing precision for arrival of bunches at the collision point is required to be 0.1 picosecond or better. We studied the bunch-to-bunch timing accuracy of a “phase detector” installed in AØ in order to determine its suitability as an ILC bunch timing device. A phase detector is an RF structure excited by the passage of a bunch. Its signal is fed through a 1240 MHz high-Q resonant circuit and then down-mixed with the AØ 1300 MHz accelerator RF. We used a kind of autocorrelation technique to compare the phase detector signal with a reference signal obtained from the phase detector’s response to an event at the beginning of the run. We determined that the device installed in our beam, which was instrumented with an 8-bit 500 MHz ADC, could measure the beam timing to an accuracy of 0.4 picoseconds. Simulations of the device showed that an increase in ADC clock rate to 2 GHz would improve measurement precision by the required factor of four. As a result, we felt that a device of this sort, assuming matters concerning dynamic range and long-term stability can be addressed successfully, would work at the ILC. Cost effective operation of the ILC will demand highly reliable, fault tolerant and adaptive solutions for both hardware and software. The large numbers of subsystems and large multipliers associated with the modules in those subsystems will cause even a strong level of unit reliability to become an unacceptable level of system availability. An evaluation effort is underway to evaluate standards associated with high availability, and to guide ILC development with standard practices and well-supported commercial solutions. One area of evaluation involves the Advanced Telecom Computing Architecture (ATCA) hardware and software. We worked with an ATCA crate, processor monitors, and a small amount of ATCA circuit boards in order to develop a backplane “spy” board that would let us watch the ATCA backplane communications and pursue development of an inexpensive processor monitor that could be used as a physics-driven component of the crate-level controls system. We made good progress, and felt that we had determined a productive direction to extend this work. We felt that we had learned enough to begin designing a workable processor monitor chip if there were to be sufficient interest in ATCA shown by the ILC community. Fault recognition is a challenging issue in the crafting a high reliability controls system. With tens of thousands of independent processors running hundreds of thousands of critical processes, how can the system identify that a problem has arisen and determine the appropriate steps to take to correct, or compensate, for the failure? One possible solution might come through the use of the OpenClovis supervisory system, which runs on Linux processors and allows a select set of processors to monitor the behavior of individual processes and processors in a large, distributed controls network. We found that OpenClovis exhibited an irritating amount of sensitivity to the exact version of the Linux kernel running on the processors, and that it was poorly equipped to help us sort through problems that arose through conflicts so deep in the operating systems of the processors. But once this issue was addressed, we found that it performed as expected, recognizing crashes and process (and processor) failures.

  6. Development of Polarized Photocathodes for the Linear Collider

    SciTech Connect

    Richard Prepost

    2009-12-22

    In prior years a Wisconsin-SLAC collaboration developed polarized photocathodes which were used for the SLAC SLD and fixed target programs. Currently, the R&D program goal is the development of a polarized electron source (PES) which meets the ILC requirements for polarization, charge, lifetime, and pulse structure. There are two parts to this program. One part is the continued improvement of photocathode structures with higher polarization. The second part is the design and development of the laser system used to drive the photocathode. The long pulse train for the ILC introduces new challenges for the PES. More reliable and stable operation of the PES may be achievable if appropriate R&D is carried out for higher voltage operation and for a simpler photocathode load-lock system. The collaboration with SLAC is through the Polarized Photocathode Research Collaboration (PPRC). Senior SLAC personnel include T. Maruyama, J. Clendenin, R. Kirby, and A. Brachmann.

  7. Millimeter-wave structures and drivers for future linear colliders

    SciTech Connect

    Nassiri, A.; Kang, Y.W.; Song, J.J.

    2000-07-24

    There is a growing interest in the development of very high gradient ({ge} GeV/meter) accelerating structures and millimeter-wave power sources. The need for very high gradient structures to be operated in W-band or at higher frequencies poses great technical challenges and demands innovations in rf science and technology to reach this goal. Requirements for microstructure fabrication and power sources based on deep x-ray lithography techniques are examined.

  8. Vibration Model Validation for Linear Collider Detector Platforms

    SciTech Connect

    Bertsche, Kirk; Amann, J.W.; Markiewicz, T.W.; Oriunno, M.; Weidemann, A.; White, G.; /SLAC

    2012-05-16

    The ILC and CLIC reference designs incorporate reinforced-concrete platforms underneath the detectors so that the two detectors can each be moved onto and off of the beamline in a Push-Pull configuration. These platforms could potentially amplify ground vibrations, which would reduce luminosity. In this paper we compare vibration models to experimental data on reinforced concrete structures, estimate the impact on luminosity, and summarize implications for the design of a reinforced concrete platform for the ILC or CLIC detectors.

  9. Precision measurement of a particle mass at the linear collider

    SciTech Connect

    Milstene, C.; Freitas, A.; Schmitt, M.; Sopczak, A.; /Lancaster U.

    2007-06-01

    Precision measurement of the stop mass at the ILC is done in a method based on cross-sections measurements at two different center-of-mass energies. This allows to minimize both the statistical and systematic errors. In the framework of the MSSM, a light stop, compatible with electro-weak baryogenesis, is studied in its decay into a charm jet and neutralino, the Lightest Supersymmetric Particle (LSP), as a candidate of dark matter. This takes place for a small stop-neutralino mass difference.

  10. International Linear Collider Technical Design Report (Volumes 1 through 4)

    SciTech Connect

    Harrison M.

    2013-03-27

    The design report consists of four volumes: Volume 1, Executive Summary; Volume 2, Physics; Volume 3, Accelerator (Part I, R and D in the Technical Design Phase, and Part II, Baseline Design); and Volume 4, Detectors.

  11. 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.

  12. Operational decoupling in the SSC Collider

    SciTech Connect

    Bourianoff, G.

    1991-11-01

    This paper will summarize a recent study of the effects and correction of linear coupling in the Superconducting Super Collider (SSC) lattice. There are several aspects of the SSC lattice that make direct extrapolation of techniques used on existing machines unreliable. The most obvious aspect of the SSC which departs from previous experience is the small dynamic aperture which lies well within the beampipe. A second aspect is the existence of long arcs with low superperiodicity which allow various sources of skew quadrupole to accumulate to large, and, perhaps, nonlinear values. A third aspect is the relatively large value of systematic skew quadrupole error in the main dipoles. This results from asymmetric placement of the cold mass in the cryostat. Coupling must be considered harmful if it leads to irreversible emittance blow-up, a decrease in the dynamic aperture, or inoperability of the machine. These negative effects are generally related to coupling terms that accumulate to large and, hence, nonlinear values prior to correction. The harmful effects can also be caused by the linearly coupled orbits interacting with high-order multipole fields that exist in the other magnets.

  13. 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.

  14. Disambiguating seesaw models using invariant mass variables at hadron colliders

    NASA Astrophysics Data System (ADS)

    Dev, P. S. Bhupal; Kim, Doojin; Mohapatra, Rabindra N.

    2016-01-01

    We propose ways to distinguish between different mechanisms behind the collider signals of TeV-scale seesaw models for neutrino masses using kinematic endpoints of invariant mass variables. We particularly focus on two classes of such models widely discussed in literature: (i) Standard Model extended by the addition of singlet neutrinos and (ii) Left-Right Symmetric Models. Relevant scenarios involving the same "smoking-gun" collider signature of dilepton plus dijet with no missing transverse energy differ from one another by their event topology, resulting in distinctive relationships among the kinematic endpoints to be used for discerning them at hadron colliders. These kinematic endpoints are readily translated to the mass parameters of the on-shell particles through simple analytic expressions which can be used for measuring the masses of the new particles. A Monte Carlo simulation with detector effects is conducted to test the viability of the proposed strategy in a realistic environment. Finally, we discuss the future prospects of testing these scenarios at the √{s}=14 and 100 TeV hadron colliders.

  15. Disambiguating seesaw models using invariant mass variables at hadron colliders

    DOE PAGES

    Dev, P. S. Bhupal; Kim, Doojin; Mohapatra, Rabindra N.

    2016-01-19

    Here, we propose ways to distinguish between different mechanisms behind the collider signals of TeV-scale seesaw models for neutrino masses using kinematic endpoints of invariant mass variables. We particularly focus on two classes of such models widely discussed in literature: (i) Standard Model extended by the addition of singlet neutrinos and (ii) Left-Right Symmetric Models. Relevant scenarios involving the same "smoking-gun" collider signature of dilepton plus dijet with no missing transverse energy differ from one another by their event topology, resulting in distinctive relationships among the kinematic endpoints to be used for discerning them at hadron colliders. Furthermore, these kinematic endpoints are readily translated to the mass parameters of the on-shell particles through simple analytic expressions which can be used for measuring the masses of the new particles. We also conducted a Monte Carlo simulation with detector effects in order to test the viability of the proposed strategy in a realistic environment. Finally, we discuss the future prospects of testing these scenarios at themore » $$\\sqrt{s}$$ = 14 and 100TeV hadron colliders.« less

  16. Disambiguating seesaw models using invariant mass variables at hadron colliders

    SciTech Connect

    Dev, P. S. Bhupal; Kim, Doojin; Mohapatra, Rabindra N.

    2016-01-19

    Here, we propose ways to distinguish between different mechanisms behind the collider signals of TeV-scale seesaw models for neutrino masses using kinematic endpoints of invariant mass variables. We particularly focus on two classes of such models widely discussed in literature: (i) Standard Model extended by the addition of singlet neutrinos and (ii) Left-Right Symmetric Models. Relevant scenarios involving the same "smoking-gun" collider signature of dilepton plus dijet with no missing transverse energy differ from one another by their event topology, resulting in distinctive relationships among the kinematic endpoints to be used for discerning them at hadron colliders. Furthermore, these kinematic endpoints are readily translated to the mass parameters of the on-shell particles through simple analytic expressions which can be used for measuring the masses of the new particles. We also conducted a Monte Carlo simulation with detector effects in order to test the viability of the proposed strategy in a realistic environment. Finally, we discuss the future prospects of testing these scenarios at the $\\sqrt{s}$ = 14 and 100TeV hadron colliders.

  17. 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

  18. Accelerator Science: Circular vs. Linear

    ScienceCinema

    Lincoln, Don

    2016-12-14

    Particle accelerator are scientific instruments that allow scientists to collide particles together at incredible energies to study the secrets of the universe. However, there are many manners in which particle accelerators can be constructed. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of circular and linear accelerators.

  19. Accelerator Science: Circular vs. Linear

    SciTech Connect

    Lincoln, Don

    2016-11-10

    Particle accelerator are scientific instruments that allow scientists to collide particles together at incredible energies to study the secrets of the universe. However, there are many manners in which particle accelerators can be constructed. In this video, Fermilab’s Dr. Don Lincoln explains the pros and cons of circular and linear accelerators.

  20. Plasma lens experiments at the Final Focus Test Beam

    SciTech Connect

    Barletta, B. |; Chattopadhyay, S.; Chen, P.

    1993-04-01

    We intend to carry out a series of plasma lens experiments at the Final Focus Test Beam facility at SLAC. These experiments will be the first to study the focusing of particle beams by plasma focusing devices in the parameter regime of interest for high energy colliders, and is expected to lead to plasma lens designs capable of unprecedented spot sizes. Plasma focusing of positron beams will be attempted for the first time. We will study the effects of lens aberrations due to various lens imperfections. Several approaches will be applied to create the plasma required including laser ionization and beam ionization of a working gas. At an increased bunch population of 2.5 {times} 10{sup 10}, tunneling ionization of a gas target by an electron beam -- an effect which has never been observed before -- should be significant. The compactness of our device should prove to be of interest for applications at the SLC and the next generation linear colliders.

  1. 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.

  2. 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.

  3. 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.

  4. Stability of colliding ion beams

    SciTech Connect

    Foote, E.A.; Kulsrud, R.M.

    1980-11-01

    We determine conditions for stability of two identical colliding ion beams in the presence of neutralizing electrons, but no background ions. Such a situation is envisioned for the Counterstreaming Ion Torus. The ion beams are taken to be Maxwellian in their frames of reference. The approximation of electrostatic and electromagnetic modes is made. The stability of the electrostatic modes depends on the relation between the ion electron temperature ratio and the relative beam velocities. The stability of the electromagnetic mode depends on the relation between the ion plasma ..beta.. and the relative beam velocities.

  5. 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.

  6. LHC: The Large Hadron Collider

    ScienceCinema

    Lincoln, Don

    2016-07-12

    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.

  7. 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.

  8. Muon Colliders and Neutrino Factories

    SciTech Connect

    Kaplan, Daniel M.

    2015-05-29

    Muon colliders and neutrino factories are attractive options for future facilities aimed at achieving the highest lepton-antilepton collision energies and precision measurements of Higgs boson and neutrino mixing matrix parameters. The facility performance and cost depend on how well a beam of muons can be cooled. Recent progress in muon cooling design studies and prototype tests nourishes the hope that such facilities could be built starting in the coming decade. The status of the key technologies and their various demonstration experiments is summarized. Prospects "post-P5" are also discussed.

  9. Probing contact interactions at high energy lepton colliders

    SciTech Connect

    Cheung, K.; Godfrey, S.; Hewett, J.A.

    1996-12-01

    Fermion compositeness and other new physics can be signaled by the presence of a strong four-fermion contact interaction. Here the authors present a study of {ell}{ell}qq and {ell}{ell}{ell}{prime}{ell}{prime} contact interactions using the reactions: {ell}{sup +}{ell}{sup {minus}} {r_arrow} {ell}{prime}{sup +} {ell}{prime}{sup {minus}}, b{anti b}, c{anti c} at future e{sup +}e{sup {minus}} linear colliders with {radical}s = 0.5--5 TeV and {mu}{sup +}{mu}{sup {minus}} colliders with {radical}s = 0.5, 4 TeV. They find that very large compositeness scales can be probed at these machines and that the use of polarized beams can unravel their underlying helicity structure.

  10. Design of beam optics for the future circular collider e+e- collider rings

    DOE PAGES

    Oide, Katsunobu; Aiba, M.; Aumon, S.; ...

    2016-11-21

    A beam optics scheme has been designed for the future circular collider- e+e- (FCC-ee). The main characteristics of the design are: beam energy 45 to 175 GeV, 100 km circumference with two interaction points (IPs) per ring, horizontal crossing angle of 30 mrad at the IP and the crab-waist scheme [P. Raimondi, D. Shatilov, and M. Zobov, arXiv:physics/0702033; P. Raimondi, M. Zobov, and D. Shatilov, in Proceedings of the 22nd Particle Accelerator Conference, PAC-2007, Albuquerque, NM (IEEE, New York, 2007), p. TUPAN037.] with local chromaticity correction. The crab-waist scheme is implemented within the local chromaticity correction system without additional sextupoles,more » by reducing the strength of one of the two sextupoles for vertical chromatic correction at each side of the IP. So-called “tapering” of the magnets is applied, which scales all fields of the magnets according to the local beam energy to compensate for the effect of synchrotron radiation (SR) loss along the ring. An asymmetric layout near the interaction region reduces the critical energy of SR photons on the incoming side of the IP to values below 100 keV, while matching the geometry to the beam line of the FCC proton collider (FCC-hh) [A. Chancé et al., Proceedings of IPAC’16, 9–13 May 2016, Busan, Korea, TUPMW020 (2016).] as closely as possible. Sufficient transverse/longitudinal dynamic aperture (DA) has been obtained, including major dynamical effects, to assure an adequate beam lifetime in the presence of beamstrahlung and top-up injection. In particular, a momentum acceptance larger than ±2% has been obtained, which is better than the momentum acceptance of typical collider rings by about a factor of 2. The effects of the detector solenoids including their compensation elements are taken into account as well as synchrotron radiation in all magnets. The optics presented in this study is a step toward a full conceptual design for the collider. Finally, a number of issues have

  11. 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.

  12. Results from p p colliders

    SciTech Connect

    Huth, J.

    1991-08-01

    Recent results {bar p}p colliders are presented. From elastic scattering experiments at the Tevatron, an average value of {sigma}{sub tot} = 72.1{plus minus}2 mb is reported, along with a new measurement of {rho} = 0.13 {plus minus} 0.7. New measurements of jet direct photon and high p{sub t} W and Z production are compared to more precise, higher order predictions from perturbative QCD. Recently available data on the W mass and width give combined values for M{sub W} = 80.14{plus minus}0.27 GeV/c{sup 2}, and {Gamma}(W) =2. 14 {plus minus} 0.08 GeV. From electroweak radiative corrections and M{sub W}, one finds M{sub top} = 130{plus minus}40 GeV/c{sup 2}, with a 95% C.L. upper limit at 210 GeV/c{sup 2}. Current limits on M{sub top} are presented, along with a review of the prospects for top discovery. From jet data there is no evidence of quark substructure down to the distance scale of 1.4 {times} 10{sup {minus}17} cm, nor is there evidence for supersymmetry or heavy gauge bosons at {bar p}p colliders, allowing lower limits on M{sub W}, > 520 GeV/c{sup 2} and M{sub Z} 412 GeV/c{sup 2}. 66 refs., 26 figs.

  13. Computing and data handling requirements for SSC (Superconducting Super Collider) and LHC (Large Hadron Collider) experiments

    SciTech Connect

    Lankford, A.J.

    1990-05-01

    A number of issues for computing and data handling in the online in environment at future high-luminosity, high-energy colliders, such as the Superconducting Super Collider (SSC) and Large Hadron Collider (LHC), are outlined. Requirements for trigger processing, data acquisition, and online processing are discussed. Some aspects of possible solutions are sketched. 6 refs., 3 figs.

  14. Towards a Small Emittance Design of the JLEIC Electron Collider Ring

    SciTech Connect

    Lin, Fanglei; Derbenev, Yaroslav; Hutton, Andrew M.; Morozov, Vasiliy; Pilat, Fulvia C.; Zhang, Yuhong

    2016-05-01

    The electron collider ring of the Jefferson Lab Electron-Ion Collider (JLEIC) is designed to provide an electron beam with a small beam size at the IP for collisions with an ion beam in order to reach a desired high luminosity. For a chosen beta-star at the IP, electron beam size is determined by the equilibrium emittance that can be obtained through a linear optics design. This paper briefly describes the baseline design of the electron collider ring reusing PEP-II components and considering their parameters (such as dipole sagitta, magnet field strengths and acceptable synchrotron radiation power) and reports a few approaches to reducing the equilibrium emittance in the electron collider ring.

  15. 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.

  16. A Dynamic Alignment System for the Final Focus Test Beam

    SciTech Connect

    Ruland, R.E.; Bressler, V.E.; Fischer, G.; Plouffe, D.; /SLAC

    2005-08-16

    The Final Focus Test Beam (FFTB) was conceived as a technological stepping stone on the way to the next linear collider. Nowhere is this more evident than with the alignment subsystems. Alignment tolerances for components prior to beam turn are almost an order of magnitude smaller than for previous projects at SLAC. Position monitoring systems which operate independent of the beam are employed to monitor motions of the components locally and globally with unprecedented precision. An overview of the FFTB alignment system is presented herein.

  17. Workshop on Colliding Winds in Binary Stars to Honor Jorge Sahade

    NASA Astrophysics Data System (ADS)

    Niemela, Virpi; Morrell, Nidia; Pismis, Paris; Torres-Peimbert, Silvia

    1996-12-01

    Topics considered include: the beginning of the story; mass flow in and out of close binaries; winds of massive, main sequence close binaries; chromospheric activity, stellar winds and red stragglers; uv observations of mass transfer in algols; the circumstellar matter in pre-supernovae of type Ia; observations of colliding winds in O-type binaries; colliding winds in massive binaries involving Wolf-Rayet stars; episodic dust formation by Wolf-Rayet stars: smoke signals from colliding winds; x-ray emission from colliding wind binaries; colliding stellar winds: a new method of determining mass-loss rates via x-ray spectroscopy; sudden radiative braking in colliding hot-star winds; optical observations of colliding winds in gamma2 velorum; left overs for dinner; HD 5980: the Wolf-Rayet binary that became a luminous blue variable; the erupting Wolf-Rayet binary HD 5980 in the small magellanic cloud: spectral transition from B1.5Ia(+) to WN6 and the accompanying light curve; the elliptic orbit of the WR binary system CV serpentis; evidence for colliding winds in WR 146; is there wind-wind collision in WR 141 (HD 193928)?; search for interacting winds in the WN7 + O binary; line formation in CH Cyg: a symbiotic binary; period analysis of radial velocity of pleione; H(alpha) detection of colliding winds in O-type binaries; HD 5980 in the infrared; photometric and polarimetric observations of the Wolf-Rayet eclipsing binary HD 5980 in the small magellanic cloud, and analysis of linear polarization in two Wolf-Rayet binary systems.

  18. Type II seesaw model and multilepton signatures at hadron colliders

    NASA Astrophysics Data System (ADS)

    Mitra, Manimala; Niyogi, Saurabh; Spannowsky, Michael

    2017-02-01

    We investigate multilepton signatures, arising from the decays of doubly charged and singly charged Higgs bosons in the Type II seesaw model. Depending on the vacuum expectation value of the triplet vΔ , the doubly and singly charged Higgs bosons can decay into a large variety of multilepton final states. We explore all possible decay modes corresponding to different regimes of vΔ that generate distinguishing four and five leptonic signatures. We focus on the 13 TeV Large Hadron Collider (LHC) and further extend the study to a very high energy proton-proton collider (VLHC) with a center-of-mass energy of 100 TeV. We find that a doubly charged Higgs boson of masses around 375 GeV can be discovered at immediate LHC runs. A heavier mass of 630 GeV can instead be discovered at the high-luminosity run of the LHC or at the VLHC with 30 fb-1 .

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

    ScienceCinema

    None

    2016-07-12

    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.

  20. Error Correction for the JLEIC Ion Collider Ring

    SciTech Connect

    Wei, Guohui; Morozov, Vasiliy; Lin, Fanglei; Zhang, Yuhong; Pilat, Fulvia C.; Nosochkov, Yuri; Wang, Min-Huey

    2016-05-01

    The sensitivity to misalignment, magnet strength error, and BPM noise is investigated in order to specify design tolerances for the ion collider ring of the Jefferson Lab Electron Ion Collider (JLEIC) project. Those errors, including horizontal, vertical, longitudinal displacement, roll error in transverse plane, strength error of main magnets (dipole, quadrupole, and sextupole), BPM noise, and strength jitter of correctors, cause closed orbit distortion, tune change, beta-beat, coupling, chromaticity problem, etc. These problems generally reduce the dynamic aperture at the Interaction Point (IP). According to real commissioning experiences in other machines, closed orbit correction, tune matching, beta-beat correction, decoupling, and chromaticity correction have been done in the study. Finally, we find that the dynamic aperture at the IP is restored. This paper describes that work.

  1. Relic density and future colliders: inverse problem(s)

    SciTech Connect

    Arbey, Alexandre; Mahmoudi, Farvah

    2010-06-23

    Relic density calculations are often used to constrain particle physics models, and in particular supersymmetry. We will show that the presence of additional energy or entropy before the Big-Bang nucleosynthesis can however completely change the relic density constraints on the SUSY parameter space. Therefore one should be extremely careful when using the relic density to constrain supersymmetry as it could give misleading results, especially if combined with the future collider data. Alternatively, we will also show that combining the discoveries of the future colliders with relic density calculations can shed light on the inaccessible pre-BBN dark time physics. Finally we will present SuperIso Relic, a new relic density calculator code in Supersymmetry, which incorporates alternative cosmological models, and is publicly available.

  2. The Proton as Seen by the HERA Collider

    NASA Astrophysics Data System (ADS)

    Abt, Iris

    2016-10-01

    Deep-inelastic electron-proton (ep) scattering at the HERA collider has been very important in the investigation of the partonic structure of the proton. The neutral- and charged-current cross sections, measured over a large kinematic range, are one of the legacies of the first and so far only ep collider. Here I discuss the combination of H1 and ZEUS data. The HERA data alone can provide parton distribution functions (PDFs) within the framework of perturbative QCD. I also discuss the family of sets of PDFs called HERAPDF2.0 as well as the interpretation of such proton PDFs that characterize proton interactions in momentum space. I then introduce other possible applications of the precision cross sections. In addition, some measurements at HERA provide hints about spatial aspects of the proton. Finally, I present a brief discussion of the connection to nuclear physics.

  3. 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.

  4. 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.

  5. 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).

  6. Instability of colliding metastable strings

    NASA Astrophysics Data System (ADS)

    Hiramatsu, Takashi; Eto, Minoru; Kamada, Kohei; Kobayashi, Tatsuo; Ookouchi, Yutaka

    2014-01-01

    The breaking of U(1) R symmetry plays a crucial role in modeling the breaking of supersymmetry (SUSY). In the models that possess both SUSY preserving and SUSY breaking vacua, tube-like cosmic strings called R-tubes, whose surfaces are constituted by domain walls interpolating a false and a true vacuum with some winding numbers, can exist. Their (in)stability can strongly constrain SUSY breaking models theirselves. In the present study, we investigate the dynamical (in)stability of two colliding metastable tube-like strings by field-theoretic simulations. From them, we find that the strings become unstable, depending on the relative collision angle and speed of two strings, and the false vacuum is eventually filled out by the true vacuum owing to rapid expansion of the strings or unstable bubbles created as remnants of the collision.

  7. 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.

  8. 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.

  9. Coherent synchrotron radiation in the isochronous muon collider ring

    SciTech Connect

    Gallardo, J.C.

    1996-10-01

    To achieve the luminosity of L = 10{sup 35} cm{sup {minus}2}s{sup {minus}1} in a {mu}{sup +}{mu}{sup {minus}} collider, two bunches per sign of N = 2 {times} 10{sup 12} particles each and a betatron function of {beta}* = 3 mm at the interaction point (IP) are required. This small {beta}* at the IP constrains the size of the bunch to be {sigma}{sub z} {approximately} {beta}*. To maintain this rather short bunch without excessive rf power consumption, an isochronous lattice has been chosen for the final collider ring. One of the important advantages of muons as opposed to electrons is that at up to at least TeV energy it is possible to accelerate muons in circular machines as their synchrotron radiation is reduced by a factor of (m{sub e}/m{sub {mu}}){sup 2} {approximately} 23 {times} 10{sup {minus}6} with respect to electrons. Nevertheless, the large number of muons in a short bunch suggests the possibility of strong shielded coherent synchrotron radiation. First, the author uses the well known formulae to evaluate the power of shielded coherent synchrotron radiation in the isochronous muon collider ring. Finally, following the results obtained by Kheifets and Zotter for a bunch with a Gaussian longitudinal charge distribution the author shows that the coherent synchrotron radiation in the isochronous {mu}{sup +}{mu}{sup {minus}} collider ring is negligible if the rms bunch length is larger than {approx} 0.3 mm.

  10. Collider Phenomenology with Split-UED

    SciTech Connect

    Kong, Kyoungchul; Park, Seong Chan; Rizzo, Thomas G.; /SLAC

    2011-12-15

    able to cover the large parameter space (up to M{sub V{sub 2}} {approx} 1.5 TeV for {mu}L {ge} 1) even with early data assuming {approx}100 pb{sup -1} or less. The existence of double resonances is one essential feature arising from extra dimensional models. Whether or not one can see double resonances depends both on how degenerate the two resonances are and on the mass resolution of the detector. The very high P{sub T} from the decay makes resolution in dimuon channel worse than in dielectron final state. This is because one can reconstruct electron from ECAL but muon momentum reconstruction relies on its track, which is barely curved in this case. Further indication for SUED might be the discovery of W'-like signature of mass close to Z{sub 2}. The MUED predicts a somewhat lower event rate due to 1-loop suppressed coupling of level-2 bosons to SM fermion pair, while it exists at tree level in SUED. Therefore in UED, one has to rely on indirect production of level-2 bosons, whose collider study requires complete knowledge of the model: the mass spectrum and all the couplings. On the other hand, in the large {mu} limit of SUED, the dependence on mass spectrum is diminished since level-2 KK bosons decay only into SM fermion pairs. This allows us to estimate the signal rate from their direct production, so that they can be discovered at the early phase of the LHC. The indirect production mechanism only increases production cross sections, improving our results. Once a discovery has been made, one should try to reconstruct events and do further measurements such as spin and coupling determination, with more accumulated data, which might discriminate KK resonances from other Z' models. The coupling measurement is directly related to the determination of the bulk masses. A challenging issue might be the existence of two resonances which are rather close to each other.

  11. Final Technical Report

    SciTech Connect

    Velasco, Mayda

    2013-11-01

    This work is focused on the design and construction of novel beam diagnostic and instrumentation for charged particle accelerators required for the next generation of linear colliders. Our main interest is in non-invasive techniques. The Northwestern group of Velasco has been a member of the CLIC Test Facility 3 (CTF3) collaboration since 2003, and the beam instrumentation work is developed mostly at this facility1. This 4 kW electron beam facility has a 25-170 MeV electron LINAC. CTF3 performed a set of dedicated measurements to finalize the development of our RF-Pickup bunch length detectors. The RF-pickup based on mixers was fully commissioned in 2009 and the RF-pickup based on diodes was finished in time for the 2010-11 data taking. The analysis of all the data taken in by the summer of 2010 was finish in time and presented at the main conference of the year, LINAC 2010 in Japan.

  12. Multi-waveband observations of colliding galaxies

    NASA Astrophysics Data System (ADS)

    Appleton, P. N.; Robson, E. I.; Schombert, James M.

    1990-11-01

    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

  13. High luminosity {mu}{sup +} {mu}{sup {minus}} collider: Report of a feasibility study

    SciTech Connect

    Palmer, R.B.; Gallardo, J.C.; Tollestrup, A.; Sessler, A.

    1996-12-01

    Parameters are given of 4 TeV and 0.5 TeV (c-of-m) high luminosity {mu}{sup +}{mu}{sup -} 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. Detector background, polarization, and nonstandard operating conditions are analyzed. 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. We briefly mention the luminosity requirements of hadrons and lepton machines and their high-energy-physics advantages and disadvantages in reference to their effective center of mass energy. Finally, we present an R & D plan to determine whether such machines are practical.

  14. Probing electroweak top quark couplings at hadron colliders

    SciTech Connect

    Baur, U.; Juste, A.; Orr, L.H.; Rainwater, D.

    2005-03-01

    We consider QCD tt{gamma} and ttZ production at hadron colliders as a tool to measure the tt{gamma} and ttZ couplings. At the Tevatron it may be possible to perform a first, albeit not very precise, test of the tt{gamma} vector and axial vector couplings in tt{gamma} production, provided that more than 5 fb{sup -1} of integrated luminosity are accumulated. The ttZ cross section at the Tevatron is too small to be observable. At the CERN Large Hadron Collider (LHC) it will be possible to probe the tt{gamma} couplings at the few-percent level, which approaches the precision which one hopes to achieve with a next-generation e{sup +}e{sup -} linear collider. The LHC's capability of associated QCD ttV (V={gamma},Z) production has the added advantage that the tt{gamma} and ttZ couplings are not entangled. For an integrated luminosity of 300 fb{sup -1}, the ttZ vector (axial vector) coupling can be determined with an uncertainty of 45-85% (15-20%), whereas the dimension-five dipole form factors can be measured with a precision of 50-55%. The achievable limits improve typically by a factor of 2-3 for the luminosity-upgraded (3 ab{sup -1}) LHC.

  15. Final Report

    SciTech Connect

    Webb, Robert C.; Kamon, Teruki; Toback, David; Safonov, Alexei; Dutta, Bhaskar; Dimitri, Nanopoulos; Pope, Christopher; White, James

    2013-11-18

    Overview The High Energy Physics Group at Texas A&M University is submitting this final report for our grant number DE-FG02-95ER40917. This grant has supported our wide range of research activities for over a decade. The reports contained here summarize the latest work done by our research team. Task A (Collider Physics Program): CMS & CDF Profs. T. Kamon, A. Safonov, and D. Toback co-lead the Texas A&M (TAMU) collider program focusing on CDF and CMS experiments. Task D: Particle Physics Theory Our particle physics theory task is the combined effort of Profs. B. Dutta, D. Nanopoulos, and C. Pope. Task E (Underground Physics): LUX & NEXT Profs. R. Webb and J. White(deceased) lead the Xenon-based underground research program consisting of two main thrusts: the first, participation in the LUX two-phase xenon dark matter search experiment and the second, detector R&D primarily aimed at developing future detectors for underground physics (e.g. NEXT and LZ).

  16. Parameter choices for a muon recirculating linear accelerator from 5 to 63 GeV

    SciTech Connect

    Berg, J. S.

    2014-06-19

    A recirculating linear accelerator (RLA) has been proposed to accelerate muons from 5 to 63 GeV for a muon collider. It should be usable both for a Higgs factory and as a stage for a higher energy collider. First, the constraints due to the beam loading are computed. Next, an expression for the longitudinal emittance growth to lowest order in the longitudinal emittance is worked out. After finding the longitudinal expression, a simplified model that describes the arcs and their approximate expression for the time of flight dependence on energy in those arcs is found. Finally, these results are used to estimate the parameters required for the RLA arcs and the linac phase.

  17. 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.

  18. On the Future High Energy Colliders

    SciTech Connect

    Shiltsev, Vladimir

    2015-09-28

    High energy particle colliders have been in the forefront of particle physics for more than three decades. At present the near term US, European and international strategies of the particle physics community are centered on full exploitation of the physics potential of the Large Hadron Collider (LHC) through its high-luminosity upgrade (HL-LHC). A number of the next generation collider facilities have been proposed and are currently under consideration for the medium and far-future of accelerator-based high energy physics. In this paper we offer a uniform approach to evaluation of various accelerators based on the feasibility of their energy reach, performance potential and cost range.

  19. The VEPP-2000 electron-positron collider: First experiments

    SciTech Connect

    Berkaev, D. E. Shwartz, D. B.; Shatunov, P. Yu.; Rogovskii, Yu. A.; Romanov, A. L.; Koop, I. A.; Shatunov, Yu. M.; Zemlyanskii, I. M.; Lysenko, A. P.; Perevedentsev, E. A.; Stankevich, A. S.; Senchenko, A. I.; Khazin, B. I.; Anisenkov, A. V.; Gayazov, S. E.; Kozyrev, A. N.; Ryzhenenkov, A. E.; Shemyakin, D. N.; Epshtein, L. B.; Serednyakov, S. I.; and others

    2011-08-15

    In 2007, at the Institute of Nuclear Physics (Novosibirsk), the construction of the VEPP-2000 electron-positron collider was completed. The first electron beam was injected into the accelerator structure with turned-off solenoids of the final focus. This mode was used to tune all subsystems of the facility and to train the vacuum chamber using synchrotron radiation at electron currents of up to 150 mA. The VEPP-2000 structure with small beta functions and partially turned-on solenoids was used for the first testing of the 'round beams' scheme at an energy of 508 MeV. Beam-beam effects were studied in strong-weak and strong-strong modes. Measurements of the beam sizes in both cases showed a dependence corresponding to model predictions for round colliding beams. Using a modernized SND (spherical neutral detector), the first energy calibration of the VEPP-2000 collider was performed by measuring the excitation curve of the phimeson resonance; the phi-meson mass is known with high accuracy from previous experiments at VEEP-2M. In October 2009, a KMD-3 (cryogenic magnetic detector) was installed at the VEPP-2000 facility, and the physics program with both the SND and LMD-3 particle detectors was started in the energy range of 1-1.9 GeV. This first experimental season was completed in summer 2010 with precision energy calibration by resonant depolarization.

  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. Hourglass effects for asymmetric colliders

    SciTech Connect

    Furman, M.A.

    1991-05-01

    We give the expressions for the geometrical reduction factor of the luminosity and the geometrical beam-beam aggravating factor'' for the general asymmetric case, for tri-gaussian bunches colliding head on. With these formulas we attempt a (limited) analytic understanding of the multiparticle tracking simulations carried out for the proposed SLAC/LBL/LLNL B factory when parasitic crossings are ignored. We conclude the following: (a) the geometrical reduction in luminosity is {approximately}6% relative to the zero-bunch-length (nominal) value; (b) only the vertical beam-beam parameter of the LER is significantly altered by the hourglass effect: the geometrical enhancement of the central positron's vertical beam-beam parameter is {approximately}10% relative to the nominal value, and (c) the positrons at the head or tail of the bunch have vertical beam-beam parameters much larger than nominal. We discuss the electromagnetic disruption effect only qualitatively. This effect probably compensates (or overcompensates) the geometrical reduction of the luminosity, and it is possibly detrimental for the beam-beam parameters. 7 refs., 3 figs.

  2. Accessing the Distribution of Linearly Polarized Gluons in Unpolarized Hadrons

    SciTech Connect

    Boer, Daniel; Brodsky, Stanley J.; Mulders, Piet J.; Pisano, Cristian; /Cagliari U. /INFN, Cagliari

    2011-08-19

    Gluons inside unpolarized hadrons can be linearly polarized provided they have a nonzero transverse momentum. The simplest and theoretically safest way to probe this distribution of linearly polarized gluons is through cos2{phi} asymmetries in heavy quark pair or dijet production in electron-hadron collisions. Future Electron-Ion Collider (EIC) or Large Hadron electron Collider (LHeC) experiments are ideally suited for this purpose. Here we estimate the maximum asymmetries for EIC kinematics.

  3. Final Technical Report

    SciTech Connect

    Michael Read; R. Lawrence Ives; Patrick Ferguson

    2010-05-17

    Calabazas Creek Research Inc. (CCR) completed Phase I the development of a 10 MW, 1.3 GHz, annular beam klystron (ABK) for driving advanced accelerators, such as the International Linear Collider (ILC). Through detailed simulations in Phase I, CCR produced a design that meets all of the requirements for ILC. The ABK uses an annular beam to minimize space charge depression and the impedance. This allows the relatively low voltage of 120 kV specified for the International Linear Collider (ILC). Like the sheet beam klystron, the ABK uses a thin beam located close to the drift tube walls; however, it operates with lower risk, single mode cavities. In addition, it is azimuthally symmetric, dramatically reducing design and fabrication costs. It provides the same operating characteristics as a multi-beam klystron, but is far simpler and will be easier and less expensive to fabricate.

  4. Decoupling schemes for the SSC Collider

    SciTech Connect

    Cai, Y.; Bourianoff, G.; Cole, B.; Meinke, R.; Peterson, J.; Pilat, F.; Stampke, S.; Syphers, M.; Talman, R.

    1993-05-01

    A decoupling system is designed for the SSC Collider. This system can accommodate three decoupling schemes by using 44 skew quadrupoles in the different configurations. Several decoupling schemes are studied and compared in this paper.

  5. Calorimeter and related calculations for the Superconducting Super Collider

    SciTech Connect

    Gabriel, T.A.

    1989-02-01

    There are four topics to be covered in this paper. The first topic deals with the programs, the models, and the cross sections in the CALOR code package. Secondly, a discussion on compensating calorimetry as it applies to Fe/Si and U/Si calorimetry will be given. Thirdly, calculated results obtained on U/Si calorimeters using the CALOR system will be presented and discussed. Finally, the calculations that the Oak Ridge National Laboratory are carrying out dealing with radiation damage at the proposed Superconducting Super Collider (SSC) are described. 23 refs., 9 figs.

  6. Multivariate methods for hadronic final states in electron-positron collisions at center of mass energy = 500 GeV

    NASA Astrophysics Data System (ADS)

    Pathak, Saurav

    We approach the hadronic final state events in a future linear collider at s = 500 GeV from the knowledge discovery (data mining) point of view. We present FastCal, a fast configurable calorimeter Monte Carlo simulator for linear collider detector simulations that produces data at a rate that is 3000 times that of full simulation. Neural networks based on earlystopping are designed for the jet-combinatorial problem. CJNN, a neural network package is presented for use in the linear collider analysis environment. Neural network performances are optimized by implementing an ensemble of neural networks. A binary tree is used to obtain novel automatic cuts on physics variables. Data visualization is introduced as a crucial component of data analysis, and principal component analysis is used to understand data distributions and structures in multiple dimensions. Finally, cluster analyses with fuzzy c-means and demographic clustering are used to partition data automatically in an unsupervised regime, and we show that for fruitful use of these algorithms, understanding the data structures is crucial.

  7. The Relativistic Heavy Ion Collider, Rhic

    NASA Astrophysics Data System (ADS)

    Foelsche, H.; Hahn, H.; Harrison, M.; Ozaki, S.; Rhoades-Brown, M. J.

    1993-03-01

    The scope of the first relativistic energy heavy ion collider, RHIC, is discussed. Particular attention is paid to those novel features of a heavy ion collider that are distinct from the more usual proton machines. These features are derived from the experimental requirements of operation with a variety of ion species over a wide energy range as well as the increased demands on available ion sources and injector complexes. Storage of heavy ion beams for many hours is severely impacted by intrabeam scattering.

  8. Nuclear collisions at the Future Circular Collider

    NASA Astrophysics Data System (ADS)

    Armesto, N.; Dainese, A.; d'Enterria, D.; Masciocchi, S.; Roland, C.; Salgado, C. A.; van Leeuwen, M.; Wiedemann, U. A.

    2016-12-01

    The Future Circular Collider is a new proposed collider at CERN with centre-of-mass energies around 100 TeV in the pp mode. Ongoing studies aim at assessing its physics potential and technical feasibility. Here we focus on updates in physics opportunities accessible in pA and AA collisions not covered in previous Quark Matter contributions, including Quark-Gluon Plasma and gluon saturation studies, novel hard probes of QCD matter, and photon-induced collisions.

  9. MUON COLLIDERS - IONIZATION COOLING AND SOLENOIDS.

    SciTech Connect

    PARSA,Z.

    1999-03-29

    For a muon collider, to obtain the needed luminosity, the phase space volume must be greatly reduced within the muon life time. The ionization cooling is the preferred method used to compress the phase space and reduce the emittance to obtain high luminosity muon beams. Alternating solenoid lattices has been proposed for muon colliders, where the emittance are huge. We present an overview, discuss formalism, transfer maps for solenoid magnets and beam dynamics.

  10. Accelerator Considerations of Large Circular Colliders

    NASA Astrophysics Data System (ADS)

    Chao, Alex

    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.

  11. 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.

  12. Considerations on Energy Frontier Colliders after LHC

    SciTech Connect

    Shiltsev, Vladimir

    2016-11-15

    Since 1960’s, particle colliders have been in the forefront of particle physics, 29 total have been built and operated, 7 are in operation now. At present the near term US, European and international strategies of the particle physics community are centered on full exploitation of the physics potential of the Large Hadron Collider (LHC) through its high-luminosity upgrade (HL-LHC). The future of the world-wide HEP community critically depends on the feasibility of possible post-LHC colliders. The concept of the feasibility is complex and includes at least three factors: feasibility of energy, feasibility of luminosity and feasibility of cost. Here we overview all current options for post-LHC colliders from such perspective (ILC, CLIC, Muon Collider, plasma colliders, CEPC, FCC, HE-LHC) and discuss major challenges and accelerator R&D required to demonstrate feasibility of an energy frontier accelerator facility following the LHC. We conclude by taking a look into ultimate energy reach accelerators based on plasmas and crystals, and discussion on the perspectives for the far future of the accelerator-based particle physics. This paper largely follows previous study [1] and the presenta ion given at the ICHEP’2016 conference in Chicago [2].

  13. Symposium on General Linear Model Approach to the Analysis of Experimental Data in Educational Research (Athens, Georgia, June 29-July 1, 1967). Final Report.

    ERIC Educational Resources Information Center

    Bashaw, W. L., Ed.; Findley, Warren G., Ed.

    This volume contains the five major addresses and subsequent discussion from the Symposium on the General Linear Models Approach to the Analysis of Experimental Data in Educational Research, which was held in 1967 in Athens, Georgia. The symposium was designed to produce systematic information, including new methodology, for dissemination to the…

  14. 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.

  15. Recent Results from Hera Collider

    NASA Astrophysics Data System (ADS)

    Levonian, Sergey

    2013-11-01

    HERA collaborations H1 and ZEUS are publishing final analyses based on complete e±p statistics of ~ 0.5 fb-1 per experiment and using combinations of their data sets. Here selected recent results are presented from three areas: structure of the proton, searches for new physics and investigations of QCD phenomena at low Bjorken x.

  16. Development of a laser Doppler displacement encoder system with ultra-low-noise-level for linear displacement measurement with subnanometer resolution - Final CRADA Report

    SciTech Connect

    Shu, Deming

    2016-01-01

    An U.S. DOE Cooperative Research and Development Agreement (CRADA) between ANL and Optodyne, Inc. has been established to develop a prototype laser Doppler displacement encoder system with ultra-low noise level for linear measurements to sub-nanometer resolution for synchrotron radiation applications. We have improved the heterodyne efficiency and reduced the detector shot noises by proper shielding and adding a low-pass filter. The laser Doppler displacement encoder system prototype demonstrated a ~ 1 nm system output noise floor with single reflection optics. With multiple-pass optical arrangement, 0.1 nm scale closed-loop feedback control is achieved.

  17. Measurements of the Top Quark at the Tevatron Collider

    SciTech Connect

    Cerrito, Lucio

    2007-01-01

    The authors present recent preliminary measurements of the top-antitop pair production cross section and determinations of the top quark pole mass, performed using the data collected by the CDF and D0 Collaborations at the Tevatron Collider. In the lepton plus jets final state, with semileptonic B decay, the pair production cross section has now been measured at CDF using {approx} 760 pb{sup -1} of proton-antiproton collisions at a center-of-mass energy of {radical}s = 1.96 TeV. A measurement of the production cross section has also been made with {approx} 1 fb{sup -1} of data in the all-jets final state by the CDF Collaboration. The mass of the top quark has now been measured using {approx} 1 fb{sup -1} of collision data using all decay channels of the top quark pair, yielding the most precise measurements of the top mass to date.

  18. 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.

  19. 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.

  20. 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.

  1. 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.

  2. Survey and alignment for a 20-TeV on 20-TeV collider

    SciTech Connect

    Close, E.R.; Douglas, D.R.; Sah, R.C.

    1983-08-01

    The effects of magnet misalignments in a 20-TeV on 20-TeV anti pp collider are simulated numerically. Both short-range and long-range alignment errors are considered for an example lattice design, and closed-orbit errors are simulated. Finally, closed orbit corrections using a least-squares scheme are performed. Automatic surveying methods are attractive for a multi-TeV collider, because of the large accelerator circumference, the large number of magnets, and the small tunnel cross section. The specific example of an automatic surveying scheme based upon an Inertial Navigation System is discussed, and the most important sources of error are described.

  3. Precise Predictions for W+4-Jet Production at the Large Hadron Collider

    SciTech Connect

    Berger, C. F.; Bern, Z.; Ita, H.; Dixon, L. J.; Cordero, F. Febres; Forde, D.; Gleisberg, T.; Kosower, D. A.; Maitre, D.

    2011-03-04

    We present the next-to-leading order (NLO) QCD results for W+4-jet production at hadron colliders. This is the first hadron-collider process with five final-state objects to be computed at NLO. It represents an important background to many searches for new physics at the energy frontier. Total cross sections, as well as distributions in the jet transverse momenta, are provided for the initial LHC energy of {radical}(s)=7 TeV. We use a leading-color approximation, known to be accurate to 3% for W production with fewer jets. The calculation uses the BlackHat library along with the SHERPA package.

  4. Construction of. gamma pi. /sup 0/ spectrometer and photon tagging facility at Bates Linear Accelerator. Final report, July 31, 1979-July 31, 1980

    SciTech Connect

    Booth, E.C.

    1981-08-01

    The funds provided under Contract No. DE-AC02-79ER10486 were totally expended for hardware and supplies required by two related devices at the Bates Linear Accelerator. These were a photon tagging facility and a ..gamma pi../sup 0/ spectrometer in Beam Line C of the new South Experimental Hall. Construction was begun in November of 1979 and both systems became fully operational in the summer of 1981. Preliminary data was taken in 1980 with a prototype ..gamma pi../sup 0/ spectrometer will be carried out in the fall of 1981 and spring of 1982. The photon tagging system has been used successfully to calibrate the ..gamma pi../sup 0/ spectrometer for the BU - MIT collaboration and to test a lead glass detector system for Brandeis University.

  5. 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.

  6. 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.

  7. Slepton Pair Production at Hadron Colliders

    NASA Astrophysics Data System (ADS)

    Fuks, B.

    2007-04-01

    In R-parity conserving supersymmetric models, sleptons are produced in pairs at hadron colliders. We show that measurements of the longitudinal single-spin asymmetry at possible polarization upgrades of existing colliders allow for a direct extraction of the slepton mixing angle. A calculation of the transverse-momentum spectrum shows the importance of resummed contributions at next-to-leading logarithmic accuracy in the small and intermediate transverse-momentum regions and little dependence on unphysical scales and non-perturbative contributions.

  8. 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)

  9. 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.

  10. RF System Requirements for a Medium-Energy Electron-Ion Collider (MEIC) at JLab

    SciTech Connect

    Rimmer, Robert A; Hannon, Fay E; Guo, Jiquan; Huang, Shichun; Huang, Yulu; Wang, Haipeng; Wang, S

    2015-09-01

    JLab is studying options for a medium energy electron-ion collider that could fit on the JLab site and use CEBAF as a full-energy electron injector. A new ion source, linac and booster would be required, together with collider storage rings for the ions and electrons. In order to achieve the maximum luminosity these will be high-current storage rings with many bunches. We present the high-level RF system requirements for the storage rings, ion booster ring and high-energy ion beam cooling system, and describe the technology options under consideration to meet them. We also present options for staging that might reduce the initial capital cost while providing a smooth upgrade path to a higher final energy. The technologies under consideration may also be useful for other proposed storage ring colliders or ultimate light sources.

  11. 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.

  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. QCD parton model at collider energies

    SciTech Connect

    Ellis, R.K.

    1984-09-01

    Using the example of vector boson production, the application of the QCD improved parton model at collider energies is reviewed. The reliability of the extrapolation to SSC energies is assessed. Predictions at ..sqrt..S = 0.54 TeV are compared with data. 21 references.

  14. 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).

  15. 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.

  16. 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…

  17. Triphoton production at hadron colliders

    SciTech Connect

    Campbell, John M.; Williams, Ciaran

    2014-06-01

    We present next-to-leading order predictions for the production of triphoton final states at the LHC and the Tevatron. Our results include the effect of photon fragmentation for the first time and we are able to quantify the impact of different isolation prescriptions. We find that calculations accounting for fragmentation effects at leading order, and those employing a smooth cone isolation where no fragmentation contribution is required, are in reasonable agreement with one another. However, larger differences in the predicted rates arise when higher order corrections to the fragmentation functions are included. In addition we present full analytic results for the $\\gamma\\gamma\\gamma$ and $\\gamma\\gamma+$jet one-loop amplitudes. These amplitudes, which are particularly compact, may be useful to future higher-order calculations. Our results are available in the Monte Carlo code MCFM.

  18. Signals for top quark anomalous chromomagnetic moments at colliders

    SciTech Connect

    Rizzo, T.G.

    1994-07-01

    The Tevatron and the Next Linear Collider (NLC) will be excellent tools for probing the detailed nature of the top quark. We perform a preliminary examination of the influence of an anomalous chromomagnetic moment for the top, {kappa}, on the characteristics of t{bar t} production at the Tevatron and on the spectrum of gluon radiation associated with t{bar t} production at the NLC. In particular, we analyze the sensitivity of future data to non-zero values of {kappa} and estimate the limits that can be placed on this parameter at the Tevatron and at the NLC with center of mass of energies of {radical}s = 500 and 1000 GeV. Constraints on {kappa} from low energy processes, such as b {yields} s{gamma} are briefly discussed.

  19. A Superconducting Magnet Upgrade of the ATF2 Final Focus

    SciTech Connect

    Parker B.; Anerella M.; Escallier J.; He P.; Jain A.; Marone A.; Wanderer P.; Wu K.C.; Hauviller C.; Marin E.; Tomas R.; Zimmermann F.; Bolzon B.; Jeremie A.; Kimura N.; Kubo K.; Kume T.; Kuroda S.; Okugi T.; Tauchi T.; Terunuma N.; Tomaru T.; Tsuchiya K.; Urakawa J.; Yamamoto A.; Bambabe P.; Coe P.; Urner D.; Seryi A.; Spencer C.; White G.

    2010-05-23

    The ATF2 facility at KEK is a proving ground for linear collider technology with a well instrumented extracted beam line and Final Focus (FF). The primary ATF2 goal is to demonstrate the extreme beam demagnification and spot stability needed for a linear collider FF. But the ATF2 FF uses water cooled magnets and the ILC baseline has a superconducting (SC) FF. We plan to upgrade ATF2 and replace some of the warm FF magnets with SC FF magnets. The ATF2 SC magnets, like the ILC FF, will made via direct wind construction. ATF2 coil winding is in progress at BNL and warm magnetic measurements indicate we have achieved good field quality. Studies indicate that having ATF2 FF magnets with larger aperture and better field quality should allow reducing the ATF2 FF beta function for study of focusing regimes relevant to CLIC. The ATF2 magnet cryostat will have laser view ports for directly monitoring cold mass movement. We plan to make stability measurements at BNL and KEK to relate ATF2 FF magnet performance to that of a full length ILC QD0 R and D FF prototype under construction at BNL.

  20. A Superconducting Magnet Upgrade of the ATF2 Final Focus

    SciTech Connect

    Parker, Brett; Anerella, Michael; Escallier, John; He, Ping; Jain, Animesh; Marone, Andrew; Wanderer, Peter; Wu, Kuo-Chen; Bambade, Philip; Bolzon, Benoit; Jeremie, Andrea; Coe, Paul; Urner, David Hauviller, Claude; Marin, Eduardo; Tomas, Rogelio; Zimmermann, Frank; Kimura, Nobuhiro; Kubo, Kiyoshi; Kume, Tatsuya Kuroda, Shigeru; /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /KEK, Tsukuba /SLAC /SLAC /SLAC

    2012-07-05

    The ATF2 facility at KEK is a proving ground for linear collider technology with a well instrumented extracted beam line and Final Focus (FF). The primary ATF2 goal is to demonstrate the extreme beam demagnification and spot stability needed for a linear collider FF. But the ATF2 FF uses water cooled magnets and the ILC baseline has a superconducting (SC) FF. We plan to upgrade ATF2 and replace some of the warm FF magnets with SC FF magnets. The ATF2 SC magnets, like the ILC FF, will made via direct wind construction. ATF2 coil winding is in progress at BNL and warm magnetic measurements indicate we have achieved good field quality. Studies indicate that having ATF2 FF magnets with larger aperture and better field quality should allow reducing the ATF2 FF beta function for study of focusing regimes relevant to CLIC. The ATF2 magnet cryostat will have laser view ports for directly monitoring cold mass movement. We plan to make stability measurements at BNL and KEK to relate ATF2 FF magnet performance to that of a full length ILC QD0 R&D FF prototype under construction at BNL.

  1. Simulation Studies of Beam-Beam Effects of a Ring-Ring Electron-Ion Collider Based on CEBAF

    SciTech Connect

    Yuhong Zhang,Ji Qiang

    2009-05-01

    The collective beam-beam effect can potentially cause a rapid growth of beam sizes and reduce the luminosity of a collider to an unacceptably low level. The ELIC, a proposed ultra high luminosity electron-ion collider based on CEBAF, employs high repetition rate crab crossing colliding beams with very small bunch transverse sizes and very short bunch lengths, and collides them at up to 4 interaction points with strong final focusing. All of these features can make the beam-beam effect challenging. In this paper, we present simulation studies of the beam-beam effect in ELIC using a self-consistent strong-strong beam-beam simulation code developed at Lawrence Berkeley National Laboratory. This simulation study is used for validating the ELIC design and for searching for an optimal parameter set.

  2. PARAMETER SETS FOR 10 TEV AND 100 TEV MUON COLLIDERS, AND THEIR STUDY AT THE HEMC 99 WORKSHOP

    SciTech Connect

    KING,B.J.

    2000-05-05

    A focal point for the HEMC'99 workshop was the evaluation of straw-man parameter sets for the acceleration and collider rings of muon colliders at center of mass energies of 10 TeV and 100 TeV. These self-consistent parameter sets are presented and discussed. The methods and assumptions used in their generation are described and motivations are given for the specific choices of parameter values. The assessment of the parameter sets during the workshop is then reviewed and the implications for the feasibility of many-TeV muon colliders are evaluated. Finally, a preview is given of plans for iterating on the parameter sets and, more generally, for future feasibility studies on many-TeV muon colliders.

  3. nuSTORM and A Path to a Muon Collider

    SciTech Connect

    Adey, David; Bayes, Ryan; Bross, Alan; Snopok, Pavel

    2015-05-20

    Our article reviews the current status of the nuSTORM facility and shows how it can be utilized to perform the next step on the path toward the realization of a μ+μ- collider. This review includes the physics motivation behind nuSTORM, a detailed description of the facility and the neutrino beams it can produce, and a summary of the short-baseline neutrino oscillation physics program that can be carried out at the facility. The idea for nuSTORM (the production of neutrino beams from the decay of muons in a racetrack-like decay ring) was discussed in the literature more than 30 years ago in the context of searching for noninteracting (sterile) neutrinos. However, only in the past 5 years has the concept been fully developed, motivated in large part by the facility's unmatched reach in addressing the evolving data on oscillations involving sterile neutrinos. Finally, this article reviews the basics of the μ+μ-collider concept and describes how nuSTORM provides a platform to test advanced concepts for six-dimensional muon ionization cooling.

  4. nuSTORM and A Path to a Muon Collider

    DOE PAGES

    Adey, David; Bayes, Ryan; Bross, Alan; ...

    2015-05-20

    Our article reviews the current status of the nuSTORM facility and shows how it can be utilized to perform the next step on the path toward the realization of a μ+μ- collider. This review includes the physics motivation behind nuSTORM, a detailed description of the facility and the neutrino beams it can produce, and a summary of the short-baseline neutrino oscillation physics program that can be carried out at the facility. The idea for nuSTORM (the production of neutrino beams from the decay of muons in a racetrack-like decay ring) was discussed in the literature more than 30 years agomore » in the context of searching for noninteracting (sterile) neutrinos. However, only in the past 5 years has the concept been fully developed, motivated in large part by the facility's unmatched reach in addressing the evolving data on oscillations involving sterile neutrinos. Finally, this article reviews the basics of the μ+μ-collider concept and describes how nuSTORM provides a platform to test advanced concepts for six-dimensional muon ionization cooling.« less

  5. DEPFET detectors for future electron-positron colliders

    NASA Astrophysics Data System (ADS)

    Marinas, C.

    2015-11-01

    The DEPFET Collaboration develops highly granular, ultra-thin pixel detectors for outstanding vertex reconstruction at future electron-positron collider experiments. A DEPFET sensor, by the integration of a field effect transistor on a fully depleted silicon bulk, provides simultaneous position sensitive detector capabilities and in pixel amplification. The characterization of the latest DEPFET prototypes has proven that a adequate signal-to-noise ratio and excellent single point resolution can be achieved for a sensor thickness of 50 micrometers. The close to final auxiliary ASICs have been produced and found to operate a DEPFET pixel detector of the latest generation with the required read-out speed. A complete detector concept is being developed for the Belle II experiment at the new Japanese super flavor factory. DEPFET is not only the technology of choice for the Belle II vertex detector, but also a prime candidate for the ILC. Therefore, in this contribution, the status of DEPFET R&D project is reviewed in the light of the requirements of the vertex detector at a future electron-positron collider.

  6. 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.

  7. Space-charge limitations in a collider

    SciTech Connect

    Fedotov, A.; Heimerle, M.

    2010-08-03

    Design of several projects which envision hadron colliders operating at low energies such as NICA at JINR [1] and Electron-Nucleon Collider at FAIR [2] is under way. In Brookhaven National Laboratory (BNL), a new physics program requires operation of Relativistic Heavy Ion Collider (RHIC) with heavy ions at low energies at g=2.7-10 [3]. In a collider, maximum achievable luminosity is typically limited by beam-beam effects. For heavy ions significant luminosity degradation, driving bunch length and transverse emittance growth, comes from Intrabeam Scattering (IBS). At these low energies, IBS growth can be effectively counteracted, for example, with cooling techniques. If IBS were the only limitation, one could achieve small hadron beam emittance and bunch length with the help of cooling, resulting in a dramatic luminosity increase. However, as a result of low energies, direct space-charge force from the beam itself is expected to become the dominant limitation. Also, the interplay of both beambeam and space-charge effects may impose an additional limitation on achievable maximum luminosity. Thus, understanding at what values of space-charge tune shift one can operate in the presence of beam-beam effects in a collider is of great interest for all of the above projects. Operation of RHIC for Low-Energy physics program started in 2010 which allowed us to have a look at combined impact of beam-beam and space-charge effects on beam lifetime experimentally. Here we briefly discuss expected limitation due to these effects with reference to recent RHIC experience.

  8. 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``.

  9. Preliminary report on the design of the Superconducting Super Collider

    SciTech Connect

    1986-01-01

    While a rather detailed Conceptual Design Report will be available in April, an Superconducting Super Collider (SSC) it is appropriate to give a preview, now that the primary parameters for the Conceptual Design Report have been put down. In this preview the leading two chapters give the historical and scientific-technical background for the SSC and deal at somelength with the physics issues to be explored by the SSC. A third chapter reviews briefly the engineering and accelerator physics foundations for the developing SSC design, while the fourth lists the primary design parameters and describes the overall design. The fifth chapter describes briefly the principal engineering systems that will appear in the Conceptual Design Report, including the rather extensive injector system required. A sixth and final chapter outlines the beginnings of a ``construction plan`` put together for the purposes of exploring practical schedules and defining the critical design, development and planning paths for the overall facility and its major sub-systems.

  10. Modification of Fox-Wolfram moments for hadron colliders

    NASA Astrophysics Data System (ADS)

    Spiller, L. A.

    2016-03-01

    Collisions of composite particles impose an arbitrary boost in the longitudinal direction on a given event. This implies that the centre-of-mass frame at hadron colliders is undetermined for processes with missing energy in the final state. This motivates the modification of the Fox-Wolfram moments such that the moments for a given event are identical when viewed in the lab or centre-of-mass frame of the beam. The resulting moments are invariant under rotations in the plane transverse to the beam and boosts parallel to the beam. These moments are then used to demonstrate improved signal separation in the channel where the Higgs decays to two b-quarks while being produced in association with a vector boson.

  11. Chromaticity and low-β insertions in particle colliders

    NASA Astrophysics Data System (ADS)

    Autin, Bruno

    1990-12-01

    Besides its energy range, the main characteristic of a particle collider is its luminosity. A very important piece of equipment to achieve high luminosities is a low-β insertion, a device which focuses the beam down to a tiny spot size. The focusing limits are not only technological, they are also associated with the aberrations of such systems. This paper deals with the chromatic aberrations. In a first part, the treatment of the focusing errors is reviewed and a formalism using symbolic computation is set up so that high-order perturbations can be evaluated, although results are limited to the second-order betatron tune shift and to its interpretation. In a second part, a completely analytical theory of the final doublet of a low-β insertion is given for a special model of flat-beam focusing.

  12. Constraining new physics with collider measurements of Standard Model signatures

    NASA Astrophysics Data System (ADS)

    Butterworth, Jonathan M.; Grellscheid, David; Krämer, Michael; Sarrazin, Björn; Yallup, David

    2017-03-01

    A new method providing general consistency constraints for Beyond-the-Standard-Model (BSM) theories, using measurements at particle colliders, is presented. The method, `Constraints On New Theories Using Rivet', Contur, exploits the fact that particle-level differential measurements made in fiducial regions of phase-space have a high degree of model-independence. These measurements can therefore be compared to BSM physics implemented in Monte Carlo generators in a very generic way, allowing a wider array of final states to be considered than is typically the case. The Contur approach should be seen as complementary to the discovery potential of direct searches, being designed to eliminate inconsistent BSM proposals in a context where many (but perhaps not all) measurements are consistent with the Standard Model. We demonstrate, using a competitive simplified dark matter model, the power of this approach. The Contur method is highly scaleable to other models and future measurements.

  13. Linear Accelerators

    NASA Astrophysics Data System (ADS)

    Sidorin, Anatoly

    2010-01-01

    In linear accelerators the particles are accelerated by either electrostatic fields or oscillating Radio Frequency (RF) fields. Accordingly the linear accelerators are divided in three large groups: electrostatic, induction and RF accelerators. Overview of the different types of accelerators is given. Stability of longitudinal and transverse motion in the RF linear accelerators is briefly discussed. The methods of beam focusing in linacs are described.

  14. Searching for tt resonances at the CERN Large Hadron Collider

    SciTech Connect

    Baur, U.; Orr, L. H.

    2008-06-01

    Many new physics models predict resonances with masses in the TeV range which decay into a pair of top quarks. With its large cross section, tt production at the Large Hadron Collider (LHC) offers an excellent opportunity to search for such particles. We present a detailed study of the discovery potential of the CERN Large Hadron Collider for Kaluza-Klein (KK) excitations of the gluon in bulk Randall-Sundrum (RS) models in the tt{yields}l{sup {+-}}{nu}bbqq{sup '} (l=e, {mu}) final state. We utilize final states with one or two tagged b-quarks, and two, three or four jets (including b-jets). Our calculations take into account the finite resolution of detectors, the energy loss due to b-quark decays, the expected reduced b-tagging at large tt invariant masses, and include the background originating from Wbb+jets, (Wb+Wb)+jets, W+jets, and single top+jets production. We derive semirealistic 5{sigma} discovery limits for nine different KK gluon scenarios, and compare them with those for KK gravitons, and a Z{sub H} boson in the Littlest Higgs model. We also analyze the capabilities of the LHC experiments to differentiate between individual KK gluon models and measure the couplings of KK gluons to quarks. We find that, for the parameters and models chosen, KK gluons with masses up to about 4 TeV can be discovered at the LHC. The ability of the LHC to discriminate between different bulk RS models, and to measure the couplings of the KK gluons is found to be highly model dependent.

  15. 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.

  16. Collider signatures of flavorful Higgs bosons

    NASA Astrophysics Data System (ADS)

    Altmannshofer, Wolfgang; Eby, Joshua; Gori, Stefania; Lotito, Matteo; Martone, Mario; Tuckler, Douglas

    2016-12-01

    Motivated by our limited knowledge of the Higgs couplings to the first two generation fermions, we analyze the collider phenomenology of a class of two Higgs doublet models (2HDMs) with a nonstandard Yukawa sector. One Higgs doublet is mainly responsible for the masses of the weak gauge bosons and the third-generation fermions, while the second Higgs doublet provides mass for the lighter fermion generations. The characteristic collider signatures of this setup differ significantly from well-studied 2HDMs with natural flavor conservation, flavor alignment, or minimal flavor violation. New production mechanisms for the heavy scalar, pseudoscalar, and charged Higgs involving second-generation quarks can become dominant. The most interesting decay modes include H /A →c c ,t c ,μ μ ,τ μ and H±→c b ,c s ,μ ν . Searches for low-mass dimuon resonances are currently among the best probes of the heavy Higgs bosons in this setup.

  17. Probes of Universal Extra Dimensions at Colliders

    SciTech Connect

    Rizzo, Thomas G.

    2001-06-28

    In the Universal Extra Dimensions model of Appelquist, Cheng and Dobrescu, all of the Standard Model fields are placed in the bulk and thus have Kaluza-Klein (KK) excitations. These KK states can only be pair produced at colliders due to the tree-level conservation of KK number, with the lightest of them being stable and possibly having a mass as low as {approx_equal} 350 400 GeV. After calculating the contribution to g-2 in this model we investigate the production cross sections and signatures for these particles at both hadron and lepton colliders. We demonstrate that these signatures critically depend upon whether the lightest KK states remain stable or are allowed to decay by any of a number of new physics mechanisms. These mechanisms which induce KK decays are studied in detail.

  18. 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.

  19. 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.

  20. Testing electroweak baryogenesis with future colliders

    NASA Astrophysics Data System (ADS)

    Curtin, David; Meade, Patrick; Yu, Chiu-Tien

    2014-11-01

    Electroweak Baryogenesis (EWBG) is a compelling scenario for explaining the matter-antimatter asymmetry in the universe. Its connection to the electroweak phase transition makes it inherently testable. However, completely excluding this scenario can seem difficult in practice, due to the sheer number of proposed models. We investigate the possibility of postulating a "no-lose" theorem for testing EWBG in future e + e - or hadron colliders. As a first step we focus on a factorized picture of EWBG which separates the sources of a stronger phase transition from those that provide new sources of CP violation. We then construct a "nightmare scenario" that generates a strong first-order phase transition as required by EWBG, but is very difficult to test experimentally. We show that a 100 TeV hadron collider is both necessary and possibly sufficient for testing the parameter space of the nightmare scenario that is consistent with EWBG.

  1. 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.

  2. 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.

  3. Really large hadron collider working group summary

    SciTech Connect

    Dugan, G.; Limon, P.; Syphers, M.

    1996-12-01

    A summary is presented of preliminary studies of three 100 TeV center-of-mass hadron colliders made with magnets of different field strengths, 1.8T, 9.5T and 12.6T. Descriptions of the machines, and some of the major and most challenging subsystems, are presented, along with parameter lists and the major issues for future study.

  4. 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.

  5. 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.

  6. 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.

  7. 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.

  8. Structure and Dynamics of Colliding Plasma Jets

    DOE PAGES

    Li, C.; Ryutov, D.; Hu, S.; ...

    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

  9. 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.

  10. 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.

  11. 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.

  12. An Electron-Ion Collider at CEBAF

    SciTech Connect

    Kees de Jager; Lia Merminga; Ya. Derbenev

    2002-10-01

    Electron-ion colliders with a center of mass energy between 15 and 100 GeV, a luminosity of at least 10{sup 33}cm{sup -1}s{sup -1}, and a polarization of both beams at or above 80% have been proposed for future studies of hadronic structure. The scheme proposed here would accelerate the electron beam using the CEBAF recirculating linac with energy recovery. If all accelerating structures presently installed in the CEBAF tunnel are replaced by ones with a {approx}20 MV/m gradient, then a single recirculation results in an electron beam energy of about 5 GeV. After colliding with protons/light ions circulating in a figure-of-eight storage ring (for flexibility of spin manipulation) at an energy of up to 100 GeV, the electrons are re-injected into the CEBAF accelerator for deceleration and energy recovery. In this report several lay-out options and their respective feasibilities will be presented and discussed, together with parameters which would provide a luminosity of up to 1 x 10{sup 35} cm{sup -2}s{sup -1}. The feasibility of combining such a collider at a center-of-mass energy [sq rt] s of up to 43 GeV with a fixed target facility of 25 GeV is also explored.

  13. 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.

  14. Beam dynamics aspects of crab cavities in the CERN Large Hadron Collider

    SciTech Connect

    Sun, Y.; Calaga, R.; Assmann, R.; Barranco, J.; Tomas, R.; Weiler, T.; Zimmermann, F.; Morita, A.

    2009-10-14

    Modern colliders bring into collision a large number of bunches to achieve a high luminosity. The long-range beam-beam effects arising from parasitic encounters at such colliders are mitigated by introducing a crossing angle. Under these conditions, crab cavities (CC) can be used to restore effective head-on collisions and thereby to increase the geometric luminosity. Such crab cavities have been proposed for both linear and circular colliders. The crab cavities are rf cavities operated in a transverse dipole mode, which imparts on the beam particles a transverse kick that varies with the longitudinal position along the bunch. The use of crab cavities in the Large Hadron Collider (LHC) may not only raise the luminosity, but it could also complicate the beam dynamics, e.g., crab cavities might not only cancel synchrobetatron resonances excited by the crossing angle but they could also excite new ones, they could reduce the dynamic aperture for off-momentum particles, they could influence the aperture and orbit, also degrade the collimation cleaning efficiency, and so on. In this paper, we explore the principal feasibility of LHC crab cavities from a beam dynamics point of view. The implications of the crab cavities for the LHC optics, analytical and numerical luminosity studies, dynamic aperture, aperture and beta beating, emittance growth, beam-beam tune shift, long-range collisions, and synchrobetatron resonances, crab dispersion, and collimation efficiency will be discussed.

  15. Introduction and recent developments in γγ, γe colliders

    NASA Astrophysics Data System (ADS)

    Telnov, Valery

    2001-08-01

    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 mainly 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 luminosity in the high energy part of spectrum can reach 0.3-0.5 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 that in e+e- collisions. The key new element in photon colliders is a very powerful laser system. The most straightforward solution is "an optical storage ring (optical trap)" with diode pumped laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters.

  16. Fabrication, installation, and two-year evaluation of a 245 square meter linear Fresnel lens photovoltaic and thermal (PVT) concentrator system at Dallas/Ft. Worth (DFW) Airport, Texas. Final technical report, Phase II and Phase III

    SciTech Connect

    O'Neill, M.J.; Muzzy, D.B.

    1985-02-01

    This final technical report summarizes the results of the fabrication, installation, and two-year evaluation of the first linear Fresnel lens photovoltaic and thermal (PVT) concentrator system ever deployed. The system is located on the Central Utility Plant at DFW Airport, Texas. The roof-mounted collector field provides 245 square meters of sun-tracking collector aperture area. The nominal 25 kilowatt peak electrical output of the system is used for plant lighting, while the nominal 120 kilowatt peak thermal output is used to preheat domestic water for the nearby AMFAC hotel. The system has performed efficiently and reliably over the full two-year operational period. Long-term system conversion efficiencies have been 7.7% sunlight-to-electricity, 39.1% sunlight-to-heat, 46.8% sunlight-to-total energy output. Each of these efficiency levels is thought to be the highest ever achieved by a commercial-scale photovoltaic system. System durability has also been excellent, with no detectable degradation in performance over the full operational period. In summary, this successful application experiment has verified the potential of the linear Frenel lens PVT system to reliably and efficiently deliver electricity and heat in commercial-scale applications.

  17. Decoupling the SSC collider using local correction techniques

    SciTech Connect

    Bourianoff, G.; Pilat, F.

    1991-10-01

    This paper will summarize recent study of the effects and correction of linear coupling in the Superconducting Super Collider (SSC) lattice. There are several aspects of the SSC lattice that make direct extrapolation of techniques used on existing machines unreliable. The most obvious aspect of the SSC which departs from previous experience is the small dynamic aperture which lies well within the beampipe. A second aspect is the existence of long arcs with low superperiodicity which allows various sources of skew quadrupole to accumulate to large, and, perhaps, nonlinear values. A third aspect is the relatively large value of systematic skew quadrupole error in the main dipoles. This results from asymmetric placement of the cold mass in the cryostat. Coupling must be considered harmful if it leads to irreversible emittance blow-up, a decrease in the dynamic aperture, or inoperability of the machine. These negative effects are generally related to coupling terms that accumulate to large and, hence, nonlinear values prior to correction. The harmful effects can also be cause by the linearly coupled orbits interacting with high-order multipole fields that exist in the other magnets.

  18. Precision measurements of W and Z boson production and their decays to electrons at hadron colliders

    SciTech Connect

    Ehlers, Jans Hermann

    2006-01-01

    For many measurements at hadron colliders, such as cross sections and branching ratios, the uncertainty of the integrated luminosity is an important contribution to the error of the final result. In 1997, the ETH Zurich group proposed a new approach to determine the integrated luminosity via a counting measurement of the W and Z bosons through their decays to leptons. In this thesis this proposal has been applied on real data as well as on simulation for a future experiment.

  19. 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.

  20. Relic neutralino surface at a 100 TeV collider

    DOE PAGES

    Bramante, Joseph; Fox, Patrick J.; Martin, Adam; ...

    2015-03-11

    We map the parameter space for minimal supersymmetric Standard Model neutralino dark matter which freezes out to the observed relic abundance, in the limit that all superpartners except the neutralinos and charginos are decoupled. In this space of relic neutralinos, we show the dominant dark matter annihilation modes, the mass splittings among the electroweakinos, direct detection rates, and collider cross sections. The mass difference between the dark matter and the next-to-lightest neutral and charged states is typically much less than electroweak gauge boson masses. With these small mass differences, the relic neutralino surface is accessible to a future 100 TeVmore » hadron collider, which can discover interneutralino mass splittings down to 1 GeV and thermal relic dark matter neutralino masses up to 1.5 TeV with a few inverse attobarns of luminosity. This coverage is a direct consequence of the increased collider energy: in the Standard Model events with missing transverse momentum in the TeV range have mostly hard electroweak radiation, distinct from the soft radiation shed in compressed electroweakino decays. As a result, we exploit this kinematic feature in final states including photons and leptons, tailored to the 100 TeV collider environment.« less