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Sample records for large hadron collider

  1. A large hadron electron collider at CERN

    SciTech Connect (OSTI)

    Abelleira Fernandez, J. L.

    2015-04-06

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

  2. Director's colloquium March 18 large hadron collider

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would like submit theCovalentLaboratory | National Nuclear SecurityDirector's colloquium large

  3. Mirror World at the Large Hadron Collider

    E-Print Network [OSTI]

    Riccardo Barbieri; Thomas Gregoire; Lawrence J. Hall

    2005-09-22

    A mirror world can modify in a striking way the LHC signals of the Higgs sector. An exact or approximate Z_2 symmetry between the mirror world and our world allows large mixing between the Higgs bosons of these worlds, leading to production rates and branching ratios for these states that are markedly different from the standard model and are characteristic of a mirror world. The constraints on these Higgs boson masses from precision electroweak data differ from the standard model bound, so that the new physics that cancels the quadratic divergence induced by the top quark may appear at a larger scale, possibly beyond the reach of the LHC. However, the scale of new physics needed to cancel the quadratic divergence induced by the Higgs boson is not significantly changed. With small breakings of the Z_2 parity, the lightest mirror quarks (and possibly charged mirror leptons) could be the dark matter in the universe, forming galactic halos that are stable to cooling. A possible signal from the relic radiation density of the mirror world is also discussed.

  4. Compressed supersymmetry after 1 fb?¹ at the Large Hadron Collider

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    LeCompte, Thomas J.; Martin, Stephen P.

    2012-02-01

    We study the reach of the Large Hadron Collider with 1 fb?¹ of data at ?s=7 TeV for several classes of supersymmetric models with compressed mass spectra, using jets and missing transverse energy cuts like those employed by ATLAS for summer 2011 data. In the limit of extreme compression, the best limits come from signal regions that do not require more than 2 or 3 jets and that remove backgrounds by requiring more missing energy rather than a higher effective mass.

  5. Exploring higher dimensional black holes at the large hadron collider.

    E-Print Network [OSTI]

    Harris, Chris M.; Palmer, M. J.; Parker, Michael A.; Richardson, P.

    Preprint typeset in JHEP style - HYPER VERSION Cavendish-HEP-04/29 ATL-COM-PHYS-2004-067 Exploring Higher Dimensional Black Holes at the Large Hadron Collider C.M. Harris†, M.J. Palmer†, M.A. Parker†, P. Richardson‡, A. Sabetfakhri† and B.R. Webber... the Standard Model matter and gauge fields are confined to the physical three-branes in a higher dimensional space, it has been shown that most of the black hole decay products are Standard Model quanta emitted on the brane [7] and are therefore visible...

  6. Detecting Exotic Heavy Leptons at the Large Hadron Collider

    E-Print Network [OSTI]

    B. C. Allanach; C. M. Harris; M. A. Parker; P. Richardson; B. R. Webber

    2001-08-10

    New almost-degenerate charged and neutral heavy leptons are a feature of a number of theories of physics beyond the Standard Model. The prospects for detecting these at the Large Hadron Collider using a time-of-flight technique are considered, along with any cosmological or experimental constraints on their masses. Based on a discovery criterion of 10 detected exotic leptons we conclude that, with an integrated luminosity of 100 fb-1, it should be possible to detect such leptons provided their masses are less than 950 GeV. It should also be possible to use the angular distribution of the produced particles to distinguish these exotic leptons from supersymmetric scalar leptons, at a better than 90% confidence level, for masses up to 580 GeV.

  7. Complementarity of the CERN Large Hadron Collider and the $e^+e^-$ International Linear Collider

    E-Print Network [OSTI]

    S. Y. Choi

    2008-09-10

    The next-generation high-energy facilities, the CERN Large Hadron Collider (LHC) and the prospective $e^+e^-$ International Linear Collider (ILC), are expected to unravel new structures of matter and forces from the electroweak scale to the TeV scale. In this report we review the complementary role of LHC and ILC in drawing a comprehensive and high-precision picture of the mechanism breaking the electroweak symmetries and generating mass, and the unification of forces in the frame of supersymmetry.

  8. Department of Energy assessment of the Large Hadron Collider

    SciTech Connect (OSTI)

    NONE

    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.

  9. Exploring Small Extra Dimensions at the Large Hadron Collider

    E-Print Network [OSTI]

    B. C. Allanach; K. Odagiri; M. J. Palmer; M. A. Parker; A. Sabetfakhri; B. R. Webber

    2002-11-13

    Many models that include small extra space dimensions predict graviton states which are well separated in mass, and which can be detected as resonances in collider experiments. It has been shown that the ATLAS detector at the Large Hadron Collider can identify such narrow states up to a mass of 2080 GeV in the decay mode G->ee, using a conservative model. This work extends the study of the ee channel over the full accessible parameter space, and shows that the reach could extend as high as 3.5 TeV. It then discusses ways in which the expected universal coupling of the resonance can be confirmed using other decay modes. In particular, the mode G-> di-photons is shown to be measurable with good precision, which would provide powerful confirmation of the graviton hypothesis. The decays G-> mu mu, WW, ZZ and jet--jet are measurable over a more limited range of couplings and masses. Using information from mass and cross-section measurements, the underlying parameters can be extracted. In one test model, the size of the extra dimension can be determined to a precision in length of 7x10^-33 m.

  10. Exploring Small Extra Dimensions at the Large Hadron Collider

    E-Print Network [OSTI]

    Allanach, Benjamin C; Palmer, M J; Parker, M A; Sabetfakhri, A; Webber, Bryan R

    2002-01-01

    Many models that include small extra space dimensions predict graviton states which are well separated in mass, and which can be detected as resonances in collider experiments. It has been shown that the ATLAS detector at the Large Hadron Collider can identify such narrow states up to a mass of 2080 GeV in the decay mode $Gightarrow e^+e^-$, using a conservative model. This work extends the study of the $e^+e^-$ channel over the full accessible parameter space, and shows that the reach could extend as high as 3.5 TeV. It then discusses ways in which the expected universal coupling of the resonance can be confirmed using other decay modes. In particular, the mode $Gightarrow gammagamma$ is shown to be measurable with good precision, which would provide powerful confirmation of the graviton hypothesis. The decays $Gightarrow mu^+mu^-, W^+W^-, Z^0Z^0$ and jet--jet are measurable over a more limited range of couplings and masses. Using information from mass and cross-section measurements, the underlying parameter...

  11. The Hunt for New Physics at the Large Hadron Collider

    E-Print Network [OSTI]

    P. Nath; B. D. Nelson; H. Davoudiasl; B. Dutta; D. Feldman; Z. Liu; T. Han; P. Langacker; R. Mohapatra; J. Valle; A. Pilaftsis; D. Zerwas; S. AbdusSalam; C. Adam-Bourdarios; J. A. Aguilar-Saavedra; B. Allanach; B. Altunkaynak; L. A. Anchordoqui; H. Baer; B. Bajc; O. Buchmueller; M. Carena; R. Cavanaugh; S. Chang; K. Choi; C. Csaki; S. Dawson; F. de Campos; A. De Roeck; M. Duhrssen; O. J. P. Eboli; J. R. Ellis; H. Flacher; H. Goldberg; W. Grimus; U. Haisch; S. Heinemeyer; M. Hirsch; M. Holmes; T. Ibrahim; G. Isidori; G. Kane; K. Kong; R. Lafaye; G. Landsberg; L. Lavoura; J. S. Lee; S. J. Lee; M. Lisanti; D. Lust; M. B. Magro; R. Mahbubani; M. Malinsky; F. Maltoni; S. Morisi; M. M. Muhlleitner; B. Mukhopadhyaya; M. Neubert; K. A. Olive; G. Perez; P. Fileviez Perez; T. Plehn; E. Ponton; W. Porod; F. Quevedo; M. Rauch; D. Restrepo; T. G. Rizzo; J. C. Romao; F. J. Ronga; J. Santiago; J. Schechter; G. Senjanovic; J. Shao; M. Spira; S. Stieberger; Z. Sullivan; T. M. P. Tait; X. Tata; T. R. Taylor; M. Toharia; J. Wacker; C. E. M. Wagner; L. -T. Wang; G. Weiglein; D. Zeppenfeld; K. Zurek

    2010-01-14

    The Large Hadron Collider presents an unprecedented opportunity to probe the realm of new physics in the TeV region and shed light on some of the core unresolved issues of particle physics. These include the nature of electroweak symmetry breaking, the origin of mass, the possible constituent of cold dark matter, new sources of CP violation needed to explain the baryon excess in the universe, the possible existence of extra gauge groups and extra matter, and importantly the path Nature chooses to resolve the hierarchy problem - is it supersymmetry or extra dimensions. Many models of new physics beyond the standard model contain a hidden sector which can be probed at the LHC. Additionally, the LHC will be a top factory and accurate measurements of the properties of the top and its rare decays will provide a window to new physics. Further, the LHC could shed light on the origin of neutralino masses if the new physics associated with their generation lies in the TeV region. Finally, the LHC is also a laboratory to test the hypothesis of TeV scale strings and D-brane models. An overview of these possibilities is presented in the spirit that it will serve as a companion to the Technical Design Reports (TDRs) by the particle detector groups ATLAS and CMS to facilitate the test of the new theoretical ideas at the LHC. Which of these ideas stands the test of the LHC data will govern the course of particle physics in the subsequent decades.

  12. Neutrino experiments and the Large Hadron Collider: friends across 14 orders of magnitude

    E-Print Network [OSTI]

    Conrad, Janet

    This paper explores some of the questions that connect the Large Hadron Collider (LHC) and neutrino experiments. What is the origin of mass? What is the meaning of flavor? Is there direct evidence of new forces or particles? ...

  13. Resummation of the transverse-energy distribution in Higgs boson production at the Large Hadron Collider

    E-Print Network [OSTI]

    Massimiliano Grazzini; Andreas Papaefstathiou; Jennifer M. Smillie; Bryan R. Webber

    2014-08-25

    We compute the resummed hadronic transverse-energy ($E_T$) distribution due to initial-state QCD radiation in the production of a Standard Model Higgs boson of mass 126 GeV by gluon fusion at the Large Hadron Collider, with matching to next-to-leading order calculations at large $E_T$. Effects of hadronization, underlying event and limited detector acceptance are estimated using aMC@NLO with the Herwig++ and Pythia 8 event generators.

  14. Exploring Higher Dimensional Black Holes at the Large Hadron Collider

    E-Print Network [OSTI]

    C. M. Harris; M. J. Palmer; M. A. Parker; P. Richardson; A. Sabetfakhri; B. R. Webber

    2004-11-01

    In some extra dimension theories with a TeV fundamental Planck scale, black holes could be produced in future collider experiments. Although cross sections can be large, measuring the model parameters is difficult due to the many theoretical uncertainties. Here we discuss those uncertainties and then we study the experimental characteristics of black hole production and decay at a typical detector using the ATLAS detector as a guide. We present a new technique for measuring the temperature of black holes that applies to many models. We apply this technique to a test case with four extra dimensions and, using an estimate of the parton-level production cross section error of 20%, determine the Planck mass to 15% and the number of extra dimensions to +-0.75.

  15. Jet Physics with A Large Ion Collider Experiment at the Large Hadron Collider

    E-Print Network [OSTI]

    Klein, Jochen

    In the presence of the strongly-interacting medium created in relativistic heavy-ion collisions, highly energetic partons from hard interactions lose energy through scattering and radiating. This effect, referred to as jet quenching, is observed as a suppression of particles with large momenta transverse to the beam axis (high-$p_\\perp$). To study the impact of the medium evolution on the energy loss modelling in the Monte Carlo event generator JEWEL, we compare results obtained for different scenarios of Au-Au collisions at $\\sqrt{s_\\mathrm{NN}} = 200~\\mathrm{GeV}$. For this purpose, JEWEL was extended to use the output of relativistic hydrodynamic calculations in the OSCAR2008H format. We find the modelling of common observables, e.g. the nuclear modification factor, to be rather insensitive to the details of the medium evolution, for which the analytically accessible Bjorken expansion can thus be considered adequate. The OSCAR interface now allows further studies also at LHC energies. Jets of large transve...

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

    SciTech Connect (OSTI)

    Quigg, Chris

    2015-08-24

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

  17. Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism.

    E-Print Network [OSTI]

    Allanach, B. C.; Kom, C. H.; Pas, H.

    Fe b 2 00 9 CAVENDISH-HEP-2009-03, DAMTP-2009-15, DO-TH-09/01 Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism B. C. Allanach? DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA, United Kingdom C... to the Standard Model, a non-zero lepton number violating coupling ??111 predicts both neutrinoless double beta decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next...

  18. Design Study of a Superconducting Insertion Quadrupole Magnet for the Large Hadron Collider

    E-Print Network [OSTI]

    Kirby, G A; Taylor, T M; Yamamoto, A; Tsuchiya, K; Higashi, N; Nakamoto, T; Ogitsu, T; Ohuchi, N; Shintomi, T; Terashima, A

    1997-01-01

    The conceptual design study of a high gradient super conducting insertion quadrupole magnet has been carried out in collaboration between KEK and CERN for the Large Hadron Collider (LHC) to be built at CERN. A model magnet design has been optimized to provide a nominal design field gradient of 240 T/m with a bore aperture of 70 mm and an operational field gradient of 225 T/m at 1.9 K under radiation environment with a beam energy deposit of several watts per meter in the superconducting coils. The design and its optimization process are discussed.

  19. Undergraduate Laboratory Experiment: Measuring Matter Antimatter Asymmetries at the Large Hadron Collider

    E-Print Network [OSTI]

    Parkes, Chris; Gutierrez, J

    2015-01-01

    This document is the student manual for a third year undergraduate laboratory experiment at the University of Manchester. This project aims to measure a fundamental difference between the behaviour of matter and antimatter through the analysis of data collected by the LHCb experiment at the Large Hadron Collider. The three-body dmecays $B^\\pm \\rightarrow h^\\pm h^+ h^-$, where $h^\\pm$ is a $\\pi^\\pm$ or $K^\\pm$ are studied. The inclusive matter antimatter asymmetry is calculated, and larger asymmetries are searched for in localized regions of the phase-space.

  20. Addendum to Distinguishing Spins in Decay Chains at the Large Hadron Collider.

    E-Print Network [OSTI]

    Athanasiou, Christiana; Lester, Christopher G; Smillie, Jennifer M; Webber, Bryan R

    ar X iv :h ep -p h/ 06 06 21 2v 1 2 0 Ju n 20 06 Preprint typeset in JHEP style - PAPER VERSION Cavendish–HEP–06/15 Addendum to “Distinguishing Spins in Decay Chains at the Large Hadron Collider”? Christiana Athanasiou1, Christopher G. Lester2... such points, we have as M ?? M logR? i KLi(T, S) ? N , (2.6) which is the Monte Carlo equivalent of eq. (1.2). Results for R = 1000 and M = 5 × 107 are shown in table 4. By comparing with tables 1-3, we see that, as might be expected, – 2 – the three...

  1. Distinguishing spins in supersymmetric and universal extra dimension models at the large hadron collider.

    E-Print Network [OSTI]

    Smillie, Jennifer M; Webber, Bryan R

    ar X iv :h ep -p h/ 05 07 17 0v 3 2 1 Fe b 20 07 Preprint typeset in JHEP style - PAPER VERSION Cavendish–HEP–05/11 Distinguishing Spins in Supersymmetric and Universal Extra Dimension Models at the Large Hadron Collider? Jennifer M. Smillie1... lepton mass distribution 8 4.6 Observable quark-lepton correlations 9 5. Production cross sections 11 6. Experimental observables 13 7. Conclusions 15 A. Quark + far lepton correlation 16 B. UED production cross sections 17 1. Introduction The search...

  2. Non-Large Hadron Collider Physics Program at CERN (Conference) | SciTech

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech Connect Nanomechanical switch for|Connect Non-Large Hadron Collider Physics

  3. Searching for Narrow Graviton Resonances with the ATLAS Detector at the Large Hadron Collider

    E-Print Network [OSTI]

    Allanach, Benjamin C; Parker, M A; Webber, Bryan R

    2000-01-01

    A spectrum of massive graviton states is present in several recent theoretical models that include extra space dimensions. In some such models the graviton states are well separated in mass, and can be detected as resonances in collider experiments. The ability of the ATLAS detector at the Large Hadron Collider to identify such states and measure their properties is considered, in the case that the resonances are narrow compared to the experimental resolution. The discovery limits for the detection of the decay mode G->e+e- are derived. The angular distribution of the lepton pair is used to determine the spin of the intermediate state. In one specific model, the resonance can be detected up to a graviton resonance mass of 2080 GeV, while the angular distribution favours a spin-2 hypothesis over a spin-1 hypothesis at 90% confidence for resonance masses up to 1720 GeV.

  4. The Large Hadron Collider of CERN and the roadmap toward higher performance

    E-Print Network [OSTI]

    Rossi, L

    2012-01-01

    The Large Hadron Collider is exploring the new frontier of particle physics. It is the largest and most ambitious scientific instrument ever built and 100 years after the Rutherford experiment it continues that tradition of “smashing atoms” to unveil the secret of the infinitely small. LHC makes use of all what we learnt in 40 years of hadron colliders, in particular of ISR and Sp-pbarS at CERN and Tevatron at Fermilab, and it is based on Superconductivity, discovered also 100 years ago. Designing, developing the technology, building and finally commissioning the LHC took more than twenty years. While LHC is now successfully running, we are already preparing the future for the next step. First, by increasing of a factor five the LHC luminosity in ten years from now, and then by increasing its energy by a factor two or more, on the horizon of the next twenty years. These LHC upgrades, in luminosity and energy, will be the super-exploitation of the CERN infrastructure and is the best investment that the HEP...

  5. Proceedings of the Sixth International Workshop on Multiple Partonic Interactions at the Large Hadron Collider

    E-Print Network [OSTI]

    R. Astalos; S. Baranov; P. Bartalini; I. Belyaev; Ch. Bierlich; B. Blok; A. Buckley; F. A. Ceccopieri; I. Cherednikov; J. R. Christiansen; D. Ciangottini; M. Deak; B. Ducloue; R. Field; J. R. Gaunt; K. Golec-Biernat; L. Goerlich; A. Grebenyuk; O. Gueta; P. Gunnellini; I. Helenius; H. Jung; D. Kar; O. Kepka; M. Klusek-Gawenda; A. Knutsson; P. Kotko; M. W. Krasny; K. Kutak; E. Lewandowska; G. Lykasov; R. Maciula; A. M. Moraes; T. Martin; G. Mitsuka; L. Motyka; M. Myska; J. Otwinowski; T. Pierog; V. Pleskot; M. Rinaldi; W. Schafer; A. Siodmok; T. Sjostrand; A. Snigirev; A. Stasto; R. Staszewski; T. Stebel; M. Strikman; A. Szczurek; D. Treleani; M. Trzebinski; H. van Haevermaet; A. van Hameren; P. van Mechelen; W. Waalewijn; W. Y. Wang

    2015-06-18

    Multiple Partonic Interactions are often crucial for interpreting results obtained at the Large Hadron Collider (LHC). The quest for a sound understanding of the dynamics behind MPI - particularly at this time when the LHC is due to start its "Run II" operations - has focused the aim of this workshop. MPI@LHC2014 concentrated mainly on the phenomenology of LHC measurements whilst keeping in perspective those results obtained at previous hadron colliders. The workshop has also debated some of the state-of-the-art theoretical considerations and the modeling of MPI in Monte Carlo event generators. The topics debated in the workshop included: Phenomenology of MPI processes and multiparton distributions; Considerations for the description of MPI in Quantum Chromodynamics (QCD); Measuring multiple partonic interactions; Experimental results on inelastic hadronic collisions: underlying event, minimum bias, forward energy flow; Monte Carlo generator development and tuning; Connections with low-x phenomena, diffraction, heavy-ion physics and cosmic rays. In a total of 57 plenary talks the workshop covered a wide range of experimental results, Monte Carlo development and tuning, phenomenology and dedicated measurements of MPI which were produced with data from the LHC's Run I. Recent progress of theoretical understanding of MPI in pp, pA and AA collisions as well as the role of MPI in diffraction and small-x physics were also covered. The workshop forstered close contact between the experimental and theoretical communities. It provided a setting to discuss many of the different aspects of MPI, eventually identifying them as a unifying concept between apparently different lines of research and evaluating their impact on the LHC physics programme.

  6. BFKL dynamics at hadron colliders

    E-Print Network [OSTI]

    Carlo Ewerz; Lynne H. Orr; W. James Stirling; Bryan R. Webber

    1999-12-22

    Hadron colliders can provide important tests of BFKL `small-x' dynamics. We discuss two examples of such tests, the inclusive dijet jet cross section at large rapidity separation and the number of associated `mini-jets' in Higgs boson production.

  7. Radio Frequency Noise Effects on the CERN Large Hadron Collider Beam Diffusion

    SciTech Connect (OSTI)

    Mastoridis, T.; Baudrenghien, P.; Butterworth, A.; Molendijk, J.; Rivetta, C.; Fox, J.D.; /SLAC

    2012-04-30

    Radio frequency (rf) accelerating system noise can have a detrimental impact on the Large Hadron Collider (LHC) performance through longitudinal motion and longitudinal emittance growth. A theoretical formalism has been developed to relate the beam and rf station dynamics with the bunch length growth. Measurements were conducted at LHC to determine the performance limiting rf components and validate the formalism through studies of the beam diffusion dependence on rf noise. As a result, a noise threshold was established for acceptable performance which provides the foundation for beam diffusion estimates for higher energies and intensities. Measurements were also conducted to determine the low level rf noise spectrum and its major contributions, as well as to validate models and simulations of this system.

  8. Exergy Analysis of the Cryogenic Helium Distribution System for the Large Hadron Collider (LHC)

    E-Print Network [OSTI]

    Claudet, S; Tavian, L; Wagner, U; 10.1063/1.3422294

    2010-01-01

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

  9. Cost-Benefit Analysis of the Large Hadron Collider to 2025 and beyond

    E-Print Network [OSTI]

    Florio, Massimo; Sirtori, Emanuela

    2015-01-01

    Social cost-benefit analysis (CBA) of projects has been successfully applied in different fields such as transport, energy, health, education, and environment, including climate change. It is often argued that it is impossible to extend the CBA approach to the evaluation of the social impact of research infrastructures, because the final benefit to society of scientific discovery is generally unpredictable. Here, we propose a quantitative approach to this problem, we use it to design an empirically testable CBA model, and we apply it to the the Large Hadron Collider (LHC), the highest-energy accelerator in the world, currently operating at CERN. We show that the evaluation of benefits can be made quantitative by determining their value to users (scientists, early-stage researchers, firms, visitors) and non-users (the general public). Four classes of contributions to users are identified: knowledge output, human capital development, technological spillovers, and cultural effects. Benefits for non-users can be ...

  10. Large Area Silicon Tracking Detectors with Fast Signal Readout for the Large Hadron Collider (LHC) at CERN

    E-Print Network [OSTI]

    Köstner, S

    2005-01-01

    The Standard Model of elementary particles, which is summarized briefly in the second chapter, incorporates a number of successful theories to explain the nature and consistency of matter. However not all building blocks of this model could yet be tested by experiment. To confirm existing theories and to improve nowadays understanding of matter a new machine is currently being built at CERN, the Large Hadron Collider (LHC), described in the third chapter. LHC is a proton-proton collider which will reach unprecedented luminosities and center of mass energies. Five experiments are attached to it to give answers to questions like the existence of the Higgs meson, which allows to explain the mass content of matter, and the origin of CP-violation, which plays an important role in the baryogenesis of the universe. Supersymmetric theories, proposing a bosonic superpartner for each fermion and vice versa, will be tested. By colliding heavy ions, high energy and particle densities can be achieved and probed. This stat...

  11. Cost-Benefit Analysis of the Large Hadron Collider to 2025 and beyond

    E-Print Network [OSTI]

    Massimo Florio; Stefano Forte; Emanuela Sirtori

    2015-07-20

    Social cost-benefit analysis (CBA) of projects has been successfully applied in different fields such as transport, energy, health, education, and environment, including climate change. It is often argued that it is impossible to extend the CBA approach to the evaluation of the social impact of research infrastructures, because the final benefit to society of scientific discovery is generally unpredictable. Here, we propose a quantitative approach to this problem, we use it to design an empirically testable CBA model, and we apply it to the the Large Hadron Collider (LHC), the highest-energy accelerator in the world, currently operating at CERN. We show that the evaluation of benefits can be made quantitative by determining their value to users (scientists, early-stage researchers, firms, visitors) and non-users (the general public). Four classes of contributions to users are identified: knowledge output, human capital development, technological spillovers, and cultural effects. Benefits for non-users can be estimated, in analogy to public goods with no practical use (such as environment preservation), using willingness to pay. We determine the probability distribution of cost and benefits for the LHC since 1993 until planned decommissioning in 2025, and we find there is a 92% probability that benefits exceed its costs, with an expected net present value of about 3 billion euro, not including the unpredictable economic value of discovery of any new physics. We argue that the evaluation approach proposed here can be replicated for any large-scale research infrastructure, thus helping the decision-making on competing projects, with a socio-economic appraisal complementary to other evaluation criteria.

  12. Production of b-quark jets at the large Hadron Collider in the parton-reggeization approach

    SciTech Connect (OSTI)

    Saleev, V. A. Shipilova, A. V.

    2013-11-15

    The inclusive hadroproduction of b-quark jets and bb-bar-quark dijets at the Large Hadron Collider is considered by using the hypothesis of gluon Reggeization in t-channel exchanges at high energies. Experimental data obtained by the ATLAS Collaboration are described well within all of the presented kinematical regions for single b-quark jets and bb-bar-quark dijets without resort to any free parameters.

  13. Single and double photonuclear excitations in Pb+Pb collisions at {radical}(s{sub NN})=2.76 TeV at the CERN Large Hadron Collider

    SciTech Connect (OSTI)

    Djuvsland, Oystein; Nystrand, Joakim

    2011-04-15

    Cross sections are calculated for single and double photon exchange in ultraperipheral Pb+Pb collisions at the CERN Large Hadron Collider. The particle production is simulated with the DPMJET event generator. Large cross sections are found for particle production around midrapidity, making these processes an important background to hadronic nuclear interactions at both the trigger and analysis levels.

  14. Jet production at hadron colliders

    E-Print Network [OSTI]

    Jouttenus, Teppo T. (Teppo Tapani)

    2012-01-01

    Hadronic jets feature in many final states of interest in modern collider experiments. They form a significant Standard Model background for many proposed new physics processes and also probe QCD interactions at several ...

  15. Chiral electric field in relativistic heavy-ion collisions at energies available at the BNL Relativistic Heavy Ion Collider and at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Yang Zhong; Chun-Bin Yang; Xu Cai; Sheng-Qin Feng

    2015-10-03

    It was proposed that the electric fields may lead to chiral separation in QGP, which is called the chiral electric separation effect. The strong electromagnetic field and the QCD vacuum can both completely be produced in the off-central nuclear-nuclear collision. We used the Wood-Saxon nucleon distribution to calculate the electric field distributions of the off-central collisions. The chiral electro field spatial distribution at Relativistic Heavy-Ion Collider (RHIC) and Large Hadron Collider (LHC) energy regions are systematically studied in this paper. Compared with magnetic field spatial distribution, electric field shows some different features in relativistic heavy-ion collisions. The dependence of the electric field produced by the thermal quark in the central position with different impact parameters on the proper time with different collision energies in the RHIC and LHC energy region are studied in this paper.

  16. A Large Hadron Electron Collider at CERN: Report on the Physics and Design Concepts for Machine and Detector

    E-Print Network [OSTI]

    J. L. Abelleira Fernandez; C. Adolphsen; A. N. Akay; H. Aksakal; J. L. Albacete; S. Alekhin; P. Allport; V. Andreev; R. B. Appleby; E. Arikan; N. Armesto; G. Azuelos; M. Bai; D. Barber; J. Bartels; O. Behnke; J. Behr; A. S. Belyaev; I. Ben-Zvi; N. Bernard; S. Bertolucci; S. Bettoni; S. Biswal; J. Blümlein; H. Böttcher; A. Bogacz; C. Bracco; G. Brandt; H. Braun; S. Brodsky; O. Brüning; E. Bulyak; A. Buniatyan; H. Burkhardt; I. T. Cakir; O. Cakir; R. Calaga; V. Cetinkaya; E. Ciapala; R. Ciftci; A. K. Ciftci; B. A. Cole; J. C. Collins; O. Dadoun; J. Dainton; A. De. Roeck; D. d'Enterria; A. Dudarev; A. Eide; R. Enberg; E. Eroglu; K. J. Eskola; L. Favart; M. Fitterer; S. Forte; A. Gaddi; P. Gambino; H. García Morales; T. Gehrmann; P. Gladkikh; C. Glasman; R. Godbole; B. Goddard; T. Greenshaw; A. Guffanti; V. Guzey; C. Gwenlan; T. Han; Y. Hao; F. Haug; W. Herr; A. Hervé; B. J. Holzer; M. Ishitsuka; M. Jacquet; B. Jeanneret; J. M. Jimenez; J. M. Jowett; H. Jung; H. Karadeniz; D. Kayran; A. Kilic; K. Kimura; M. Klein; U. Klein; T. Kluge; F. Kocak; M. Korostelev; A. Kosmicki; P. Kostka; H. Kowalski; G. Kramer; D. Kuchler; M. Kuze; T. Lappi; P. Laycock; E. Levichev; S. Levonian; V. N. Litvinenko; A. Lombardi; J. Maeda; C. Marquet; S. J. Maxfield; B. Mellado; K. H. Mess; A. Milanese; S. Moch; I. I. Morozov; Y. Muttoni; S. Myers; S. Nandi; Z. Nergiz; P. R. Newman; T. Omori; J. Osborne; E. Paoloni; Y. Papaphilippou; C. Pascaud; H. Paukkunen; E. Perez; T. Pieloni; E. Pilicer; B. Pire; R. Placakyte; A. Polini; V. Ptitsyn; Y. Pupkov; V. Radescu; S. Raychaudhuri; L. Rinolfi; R. Rohini; J. Rojo; S. Russenschuck; M. Sahin; C. A. Salgado; K. Sampei; R. Sassot; E. Sauvan; U. Schneekloth; T. Schörner-Sadenius; D. Schulte; A. Senol; A. Seryi; P. Sievers; A. N. Skrinsky; W. Smith; H. Spiesberger; A. M. Stasto; M. Strikman; M. Sullivan; S. Sultansoy; Y. P. Sun; B. Surrow; L. Szymanowski; P. Taels; I. Tapan; A. T. Tasci; E. Tassi; H. Ten. Kate; J. Terron; H. Thiesen; L. Thompson; K. Tokushuku; R. Tomás García; D. Tommasini; D. Trbojevic; N. Tsoupas; J. Tuckmantel; S. Turkoz; T. N. Trinh; K. Tywoniuk; G. Unel; J. Urakawa; P. VanMechelen; A. Variola; R. Veness; A. Vivoli; P. Vobly; J. Wagner; R. Wallny; S. Wallon; G. Watt; C. Weiss; U. A. Wiedemann; U. Wienands; F. Willeke; B. -W. Xiao; V. Yakimenko; A. F. Zarnecki; Z. Zhang; F. Zimmermann; R. Zlebcik; F. Zomer

    2012-09-07

    The physics programme and the design are described of a new collider for particle and nuclear physics, the Large Hadron Electron Collider (LHeC), in which a newly built electron beam of 60 GeV, up to possibly 140 GeV, energy collides with the intense hadron beams of the LHC. Compared to HERA, the kinematic range covered is extended by a factor of twenty in the negative four-momentum squared, $Q^2$, and in the inverse Bjorken $x$, while with the design luminosity of $10^{33}$ cm$^{-2}$s$^{-1}$ the LHeC is projected to exceed the integrated HERA luminosity by two orders of magnitude. The physics programme is devoted to an exploration of the energy frontier, complementing the LHC and its discovery potential for physics beyond the Standard Model with high precision deep inelastic scattering measurements. These are designed to investigate a variety of fundamental questions in strong and electroweak interactions. The physics programme also includes electron-deuteron and electron-ion scattering in a $(Q^2, 1/x)$ range extended by four orders of magnitude as compared to previous lepton-nucleus DIS experiments for novel investigations of neutron's and nuclear structure, the initial conditions of Quark-Gluon Plasma formation and further quantum chromodynamic phenomena. The LHeC may be realised either as a ring-ring or as a linac-ring collider. Optics and beam dynamics studies are presented for both versions, along with technical design considerations on the interaction region, magnets and further components, together with a design study for a high acceptance detector. Civil engineering and installation studies are presented for the accelerator and the detector. The LHeC can be built within a decade and thus be operated while the LHC runs in its high-luminosity phase. It thus represents a major opportunity for progress in particle physics exploiting the investment made in the LHC.

  17. Simulation study of electron cloud induced instabilities and emittance growth for the CERN Large Hadron Collider proton beam

    E-Print Network [OSTI]

    Benedetto, Elena; Schulte, Daniel; Rumolo, Giovanni

    2005-01-01

    The electron cloud may cause transverse single-bunch instabilities of proton beams such as those in the Large Hadron Collider (LHC) and the CERN Super Proton Synchrotron (SPS). We simulate these instabilities and the consequent emittance growth with the code HEADTAIL, which models the turn-by-turn interaction between the cloud and the beam. Recently some new features were added to the code, in particular, electric conducting boundary conditions at the chamber wall, transverse feedback, and variable beta functions. The sensitivity to several numerical parameters has been studied by varying the number of interaction points between the bunch and the cloud, the phase advance between them, and the number of macroparticles used to represent the protons and the electrons. We present simulation results for both LHC at injection and SPS with LHC-type beam, for different electron-cloud density levels, chromaticities, and bunch intensities. Two regimes with qualitatively different emittance growth are observed: above th...

  18. Beam collimation at hadron colliders

    SciTech Connect (OSTI)

    Nikolai V. Mokhov

    2003-08-12

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

  19. Charm production in Pb+Pb collisions at the Large Hadron Collider energy

    E-Print Network [OSTI]

    Song, Taesoo; Cabrera, Daniel; Cassing, Wolfgang; Bratkovskaya, Elena

    2015-01-01

    We study charm production in Pb+Pb collisions at $\\sqrt{s_{\\rm NN}}=$2.76 TeV in the Parton-Hadron-String-Dynamics transport approach and the charm dynamics in the partonic and hadronic medium. The charm quarks are produced through initial binary nucleon-nucleon collisions by using the PYTHIA event generator taking into account the (anti-)shadowing incorporated in the EPS09 package. The produced charm quarks interact with off-shell massive partons in the quark-gluon plasma and are hadronized into $D$ mesons through coalescence or fragmentation close to the critical energy density, and then interact with hadrons in the final hadronic stage with scattering cross sections calculated in an effective Lagrangian approach with heavy-quark spin symmetry. The PHSD results show a reasonable $R_{\\rm AA}$ and elliptic flow of $D$ mesons in comparison to the experimental data for Pb+Pb collisions at $\\sqrt{s_{NN}}$ = 2.76 TeV from the ALICE Collaboration. We also study the effect of temperature-dependent off-shell charm q...

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

    E-Print Network [OSTI]

    ALICE Collaboration

    2015-07-27

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

  1. Sources of machine-induced background in the ATLAS and CMS detectors at the CERN Large Hadron Collider

    SciTech Connect (OSTI)

    Bruce, R.; et al.,

    2013-11-21

    One source of experimental background in the CERN Large Hadron Collider (LHC) is particles entering the detectors from the machine. These particles are created in cascades, caused by upstream interactions of beam protons with residual gas molecules or collimators. We estimate the losses on the collimators with SixTrack and simulate the showers with FLUKA and MARS to obtain the flux and distribution of particles entering the ATLAS and CMS detectors. We consider some machine configurations used in the first LHC run, with focus on 3.5 TeV operation as in 2011. Results from FLUKA and MARS are compared and a very good agreement is found. An analysis of logged LHC data provides, for different processes, absolute beam loss rates, which are used together with further simulations of vacuum conditions to normalize the results to rates of particles entering the detectors. We assess the relative importance of background from elastic and inelastic beam-gas interactions, and the leakage out of the LHC collimation system, and show that beam-gas interactions are the dominating source of machine-induced background for the studied machine scenarios. Our results serve as a starting point for the experiments to perform further simulations in order to estimate the resulting signals in the detectors.

  2. Search for signatures of extra dimensions in the diphoton mass spectrum at the Large Hadron Collider

    SciTech Connect (OSTI)

    Chatrchyan, Serguei; Khachatryan, Vardan; Sirunyan, Albert M.; Tumasyan, Armen; Adam, Wolfgang; Bergauer, Thomas; Dragicevic, Marko; Erö, Janos; Fabjan, Christian; Friedl, Markus; Fruehwirth, Rudolf; /Yerevan Phys. Inst. /Vienna, OAW /Minsk, High Energy Phys. Ctr. /Antwerp U., WISINF /Vrije U., Brussels /Brussels U. /Gent U. /Louvain U. /UMH, Mons /Rio de Janeiro, CBPF /Rio de Janeiro State U.

    2011-12-01

    A search for signatures of extra dimensions in the diphoton invariant-mass spectrum has been performed with the CMS detector at the LHC. No excess of events above the standard model expectation is observed using a data sample collected in proton-proton collisions at {radical}s = 7 TeV corresponding to an integrated luminosity of 2.2 fb{sup -1}. In the context of the large-extra-dimensions model, lower limits are set on the effective Planck scale in the range of 2.3-3.8 TeV at the 95% confidence level. These limits are the most restrictive bounds on virtual-graviton exchange to date. The most restrictive lower limits to date are also set on the mass of the first graviton excitation in the Randall-Sundrum model in the range of 0.86-1.84 TeV, for values of the associated coupling parameter between 0.01 and 0.10.

  3. The upgraded Pixel Detector of the ATLAS Experiment for Run2 at the Large Hadron Collider

    E-Print Network [OSTI]

    Backhaus, Malte; The ATLAS collaboration

    2015-01-01

    Run-2 of the LHC will provide new challenges to track and vertex reconstruction with higher energies, denser jets and higher rates. Therefore the ATLAS experiment has constructed the first 4-layer Pixel detector in HEP, installing a new Pixel layer, also called Insertable B-Layer (IBL). IBL is a fourth layer of pixel detectors, and has been installed in May 2014 at a radius of 3.3 cm between the existing Pixel Detector and a new smaller radius beam-pipe. To cope with the high radiation and pixel occupancy due to the proximity to the interaction point, two different silicon sensor technologies (planar and 3D) have been developed as well as a new read-out chip within CMOS 130nm technology and with larger area, smaller pixel size and faster readout capability. The new detector is the first large scale application of of 3D detectors and CMOS 130nm technology. An overview of the lessons learned during the IBL project will be presented, focusing on the challenges and highlighting the issues met during the productio...

  4. Photons and Exclusive Processes at Hadron Colliders

    E-Print Network [OSTI]

    Joakim Nystrand

    2010-01-26

    The theoretical and experimental aspects of particle production from the strong equivalent photon fluxes present at high energy hadron colliders are reviewed. The goal is to show how photons at hadron colliders can improve what we have learnt from experiments with lepton beams. Experiments during the last 5-10 years have shown the feasibility of studying photoproduction in proton-proton and heavy-ion collisions. The experimental and theoretical development has revealed new opportunities as well as challenges.

  5. Measurement of Hadronic Event Shapes and Jet Substructure in Proton-Proton Collisions at 7.0 TeV Center-of-Mass Energy with the ATLAS Detector at the Large Hadron Collider

    SciTech Connect (OSTI)

    Miller, David Wilkins

    2012-03-20

    This thesis presents the first measurement of 6 hadronic event shapes in proton-proton collisions at a center-of-mass energy of {radical}s = 7 TeV using the ATLAS detector at the Large Hadron Collider. Results are presented at the particle-level, permitting comparisons to multiple Monte Carlo event generator tools. Numerous tools and techniques that enable detailed analysis of the hadronic final state at high luminosity are described. The approaches presented utilize the dual strengths of the ATLAS calorimeter and tracking systems to provide high resolution and robust measurements of the hadronic jets that constitute both a background and a signal throughout ATLAS physics analyses. The study of the hadronic final state is then extended to jet substructure, where the energy flow and topology within individual jets is studied at the detector level and techniques for estimating systematic uncertainties for such measurements are commissioned in the first data. These first substructure measurements in ATLAS include the jet mass and sub-jet multiplicity as well as those concerned with multi-body hadronic decays and color flow within jets. Finally, the first boosted hadronic object observed at the LHC - the decay of the top quark to a single jet - is presented.

  6. Top quark studies at hadron colliders

    SciTech Connect (OSTI)

    Sinervo, P.K. [Univ. of Toronto, Ontario (Canada)

    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.

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

    SciTech Connect (OSTI)

    Yu, Jaehoon; White, Andrew

    2014-09-25

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

  8. ERL-BASED LEPTON-HADRON COLLIDERS: eRHIC AND LHeC

    E-Print Network [OSTI]

    Zimmermann, F

    2013-01-01

    Two hadron-ERL colliders are being proposed. The Large Hadron electron Collider (LHeC) plans to collide the high-energy protons and heavy ions in the Large Hadron Collider (LHC) at CERN with 60-GeV polarized electrons or positrons. The baseline scheme for this facility adds to the LHC a separate recirculating superconducting (SC) lepton linac with energy recovery, delivering a lepton current of 6.4mA. The electron-hadron collider project eRHIC aims to collide polarized (and unpolarized) electrons with a current of 50 (220) mA and energies in the range 5–30 GeV with a variety of hadron beams— heavy ions as well as polarized light ions— stored in the existing Relativistic Heavy Ion Collider (RHIC) at BNL. The eRHIC electron beam will be generated in an energy recovery linac (ERL) installed inside the RHIC tunnel.

  9. TOP AND HIGGS PHYSICS AT THE HADRON COLLIDERS

    SciTech Connect (OSTI)

    Jabeen, Shabnam

    2013-10-20

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

  10. Top Quark Pair Production in Association with a Jet with NLO QCD Off-Shell Effects at the Large Hadron Collider

    E-Print Network [OSTI]

    Bevilacqua, G; Kraus, M; Worek, M

    2015-01-01

    We present a complete description of top quark pair production in association with a jet in the dilepton channel. Our calculation is accurate to next-to-leading order in QCD (NLO) and includes all non-resonant diagrams, interferences and off-shell effects of the top quark. Moreover, non-resonant and off-shell effects due to the finite W gauge boson width are taken into account. This calculation constitutes the first fully realistic NLO computation for top quark pair production with a final state jet in hadronic collisions. Numerical results for differential distributions as well as total cross sections are presented for the Large Hadron Collider (LHC) at 8 TeV. With our inclusive cuts, NLO predictions reduce the unphysical scale dependence by more than a factor of 3 and lower the total rate by about 13% compared to leading order QCD (LO) predictions. In addition, the size of the top quark off-shell effects is estimated to be below 2%.

  11. B Physics Theory for Hadron Colliders

    E-Print Network [OSTI]

    G. Buchalla

    2008-09-03

    A short overview of theoretical methods for B physics at hadron colliders is presented. The main emphasis is on the theory of two-body hadronic B decays, which provide a rich field of investigation in particular for the Tevatron and the LHC. The subject holds both interesting theoretical challenges as well as many opportunities for flavor studies and new physics tests. A brief review of the current status and recent developments is given. A few additional topics in B physics are also mentioned.

  12. SEARCHING FOR HIGGS BOSONS AND NEW PHYSICS AT HADRON COLLIDERS

    SciTech Connect (OSTI)

    Chung Kao

    2007-09-05

    The objectives of research activities in particle theory are predicting the production cross section and decay branching fractions of Higgs bosons and new particles at hadron colliders, developing techniques and computer software to discover these particles and to measure their properties, and searching for new phenomena and new interactions at the Fermilab Tevatron and the CERN Large Hadron Collider. The results of our project could lead to the discovery of Higgs bosons, new particles, and signatures for new physics, or we will be able to set meaningful limits on important parameters in particle physics. We investigated the the prospects for the discovery at the CERN Large Hadron Collider of Higgs bosons and supersymmetric particles. Promising results are found for the CP-odd pseudoscalar ($A^0$) and the heavier CP-even scalar ($H^0$) Higgs bosons with masses up to 800 GeV. Furthermore, we study properties of the lightest neutralino ($\\chi^0$) and calculate its cosmological relic density in a supersymmetric $U(1)'$ model as well as the muon anomalous magnetic moment $a_\\mu = (g_\\mu - 2)/2$ in a supersymmetric $U(1)'$ model. We found that there are regions of the parameter space that can explain the experimental deviation of $a_\\mu$ from the Standard Model calculation and yield an acceptable cold dark matter relic density without conflict with collider experimental constraints. % Recently, we presented a complete next-to-leading order (NLO) calculation for the total cross section of inclusive Higgs pair production via bottom-quark fusion ($b\\bar{b} \\to hh$) at the CERN Large Hadron Collider (LHC) in the Standard Model and the minimal supersymmetric model. We plan to predict the Higgs pair production rate and to study the trilinear coupling among the Higgs bosons. % In addition, we have made significant contributions in B physics, single top production, charged Higgs search at the Fermilab as well as in grid computing for both D0 and ATLAS.

  13. Search for Supersymmetry Using Weak Boson Fusion Processes in Proton-Proton Collisions at the Large Hadron Collider 

    E-Print Network [OSTI]

    Flanagan, Will

    2014-08-08

    [29]. The two experiments have notably different magnet systems. ATLAS employs a small (2 Tesla) solenoid magnet just outside the tracking system (but inside the calorimeters) with a toroidal magnet at each endcap (before the muon chambers) [30... to have a 4 Tesla field, it has been operating at 3.8 Tesla to maximize magnet longevity [32]. Having such a large magnetic field allows for better momentum reconstruction through the curvature of charged particles. 2.3.2 The Tracker The inner tracker...

  14. A 233 km tunnel for lepton and hadron colliders

    SciTech Connect (OSTI)

    Summers, D. J.; Cremaldi, L. M.; Datta, A.; Duraisamy, M.; Luo, T.; Lyons, G. T. [Dept. of Physics and Astronomy, University of Mississippi-Oxford, University, MS 38677 (United States)

    2012-12-21

    A decade ago, a cost analysis was conducted to bore a 233 km circumference Very Large Hadron Collider (VLHC) tunnel passing through Fermilab. Here we outline implementations of e{sup +}e{sup -}, pp-bar , and {mu}{sup +}{mu}{sup -} collider rings in this tunnel using recent technological innovations. The 240 and 500 GeV e{sup +}e{sup -} colliders employ Crab Waist Crossings, ultra low emittance damped bunches, short vertical IP focal lengths, superconducting RF, and low coercivity, grain oriented silicon steel/concrete dipoles. Some details are also provided for a high luminosity 240 GeV e{sup +}e{sup -} collider and 1.75 TeV muon accelerator in a Fermilab site filler tunnel. The 40 TeV pp-bar collider uses the high intensity Fermilab p-bar source, exploits high cross sections for pp-bar production of high mass states, and uses 2 Tesla ultra low carbon steel/YBCO superconducting magnets run with liquid neon. The 35 TeV muon ring ramps the 2 Tesla superconducting magnets at 9 Hz every 0.4 seconds, uses 250 GV of superconducting RF to accelerate muons from 1.75 to 17.5 TeV in 63 orbits with 71% survival, and mitigates neutrino radiation with phase shifting, roller coaster motion in a FODO lattice.

  15. Single and Double Photonuclear Excitations in Pb+Pb Collisions at sqrt(s_NN) = 2.76 TeV at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Oystein Djuvsland; Joakim Nystrand

    2011-04-19

    Cross sections are calculated for single and double photon exchange in ultraperipheral Pb+Pb collisions at the LHC. The particle production is simulated with the DPMJET event generator. Large cross sections are found for particle production around mid-rapidity making these processes an important background to hadronic nuclear interactions at both the trigger and analysis levels.

  16. LHC - Large Hadon Collider Exhibition LEPFest 2000

    E-Print Network [OSTI]

    2000-01-01

    The Large Hadron Collider (LHC) will accelerate two proton beams to an energy corresponding to about 7,000 times their mass (7000 GeV). The collision of the two beams reproduces the conditions in the Universe when it was about 10 -1 2 sec old. Many innovative techniques - such as cooling with superfluid helium, the extensive use of high temperature superconducting cables, the two-in-one design for super-conducting dipole magnets, and new ultra-high vacuum technologies - had to be developed to make its construc-tion possible.

  17. Precise Predictions for Z + 4 Jets at Hadron Colliders

    SciTech Connect (OSTI)

    Ita, H.; Bern, Z.; Dixon, L.J.; Cordero, F.Febres; Kosower, D.A.; Maitre, D.

    2011-12-09

    We present the cross section for production of a Z boson in association with four jets at the Large Hadron Collider, at next-to-leading order in the QCD coupling. When the Z decays to neutrinos, this process is a key irreducible background to many searches for new physics. Its computation has been made feasible through the development of the on-shell approach to perturbative quantum field theory. We present the total cross section for pp collisions at {radical}s = 7 TeV, after folding in the decay of the Z boson, or virtual photon, to a charged-lepton pair. We also provide distributions of the transverse momenta of the four jets, and we compare cross sections and distributions to the corresponding ones for the production of a W boson with accompanying jets.

  18. Future Possibilities for Lepton-Hadron Collider Physics and Detectors

    E-Print Network [OSTI]

    Fleming, G; Lammers, S; Magill, S

    2001-01-01

    We have considered the physics opportunities of future lepton-hadron colliders and how these opportunities might be realized in a possible polarized eRHIC facility and an e-p collider as part of a staged or final version VLHC. We evaluated the physics priorities based on experience at HERA and, using simulated data for e-p collisions with sqrt(s) > 1 TeV, showed how detector designs would be impacted by the physics.

  19. Future Possibilities for Lepton-Hadron Collider Physics and Detectors

    E-Print Network [OSTI]

    G. Fleming; E. Kinney; S. Lammers; S. Magill

    2002-01-29

    We have considered the physics opportunities of future lepton-hadron colliders and how these opportunities might be realized in a possible polarized eRHIC facility and an e-p collider as part of a staged or final version VLHC. We evaluated the physics priorities based on experience at HERA and, using simulated data for e-p collisions with sqrt(s) > 1 TeV, showed how detector designs would be impacted by the physics.

  20. Resummation of transverse energy in vector boson and Higgs boson production at hadron colliders

    E-Print Network [OSTI]

    Andreas Papaefstathiou; Jennifer M. Smillie; Bryan R. Webber

    2010-02-23

    We compute the resummed hadronic transverse energy (E_T) distribution due to initial-state QCD radiation in vector boson and Higgs boson production at hadron colliders. The resummed exponent, parton distributions and coefficient functions are treated consistently to next-to-leading order. The results are matched to fixed-order calculations at large E_T and compared with parton-shower Monte Carlo predictions at Tevatron and LHC energies.

  1. Single and multiple intrabeam scattering in hadron colliders

    SciTech Connect (OSTI)

    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.

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

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

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

  3. Beam physics in future electron hadron colliders

    E-Print Network [OSTI]

    Valloni, A; Klein, M; Schulte, D; Zimmermann, F

    2013-01-01

    High-energy electron-hadron collisions could support a rich research programme in particle and nuclear physics. Several future projects are being proposed around the world, in particular eRHIC at BNL, MEIC at TJNAF in the US, and LHeC at CERN in Europe. This paper will highlight some of the accelerator physics issues, and describe related technical developments and challenges for these machines. In particular, optics design and beam dynamics studies are discussed, including longitudinal phase space manipulation, coherent synchrotron radiation, beam-beam kink instability, ion effects, as well as mitigation measures for beam break up and for space-charge induced emittance growth, all of which could limit the machine performance. Finally, first steps are presented towards an LHeC R&D facility, which should investigate relevant beam-physics processes.

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

    ScienceCinema (OSTI)

    None

    2011-10-06

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

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

    SciTech Connect (OSTI)

    2010-06-21

    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.

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

    ScienceCinema (OSTI)

    None

    2011-10-06

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

  7. Detecting Fourth Generation Quarks at Hadron Colliders

    E-Print Network [OSTI]

    David Atwood; Sudhir Kumar Gupta; Amarjit Soni

    2011-07-13

    We consider the phenomenology of the fourth generation heavy quarks which would be pair produced at the LHC. We show that if such a quark with a mass in the phenomenologically interesting range of 400 GeV--600 GeV decays to a light quark and a W-boson, it will produce a signal in a number of channels which can be seen above the background from the three generation Standard Model processes. In particular, such quarks could be seen in channels where multiple jets are present with large missing momentum and either a single hard lepton, an opposite sign hard lepton pair or a same sign lepton pair. In the same sign dilepton channel there is little background and so an excess of such pairs at large invariant mass will indicate the presence of heavy down type quarks. More generally, in our study, the main tool we use to determine the mass of the heavy quark in each of the channels we consider is to use the kinematics of the decay of such quarks to resolve the momenta of the unobserved neutrinos. We show how this can be carried out, even in cases where the kinematics is under-determined by use of the approximation, which holds quite well, that the two heavy quarks are nearly at rest in the center of mass frame. Since it is very likely that at least the lightest heavy quark decays in the mode we consider, this means that it should be observed at the LHC. Indeed, it is expected that the mass splitting between the quarks is less than $m_W$ so that if the Cabbibo-Kobayshi-Maskawa (CKM) matrix element between the fourth and lower generations are not too small, both members of the fourth generation quark doublet will decay in this way. If this is so, the combined signal of these two quarks will make the signal for the fourth generation somewhat more prominent.

  8. Hadron Collider Tests of Neutrino Mass-Generating Mechanisms

    E-Print Network [OSTI]

    Ruiz, Richard E

    2015-01-01

    The Standard Model of particle physics (SM) is presently the best description of nature at small distances and high energies. However, with tiny but nonzero neutrino masses, a Higgs boson mass unstable under radiative corrections, and little guidance on understanding the hierarchy of fermion masses, the SM remains an unsatisfactory description of nature. Well-motivated scenarios that resolve these issues exist but also predict extended gauge (e.g., Left-Right Symmetric Models), scalar (e.g., Supersymmetry), and/or fermion sectors (e.g., Seesaw Models). Hence, discovering such new states would have far-reaching implications. After reviewing basic tenets of the SM and collider physics, several beyond the SM (BSM) scenarios that alleviate these shortcomings are investigated. Emphasis is placed on the production of a heavy Majorana neutrinos at hadron colliders in the context of low-energy, effective theories that simultaneously explain the origin of neutrino masses and their smallness compared to other elementar...

  9. NLO QCD corrections to ZZ jet production at hadron colliders

    SciTech Connect (OSTI)

    Binoth, T.; Gleisberg, T.; Karg, S.; Kauer, N.; Sanguinetti, G.

    2010-05-26

    A fully differential calculation of the next-to-leading order QCD corrections to the production of Z-boson pairs in association with a hard jet at the Tevatron and LHC is presented. This process is an important background for Higgs particle and new physics searches at hadron colliders. We find sizable corrections for cross sections and differential distributions, particularly at the LHC. Residual scale uncertainties are typically at the 10% level and can be further reduced by applying a veto against the emission of a second hard jet. Our results confirm that NLO corrections do not simply rescale LO predictions.

  10. Heavy Majorana Neutrinos from $W?$ Fusion at Hadron Colliders

    E-Print Network [OSTI]

    Daniel Alva; Tao Han; Richard Ruiz

    2015-02-25

    Vector boson fusion processes become increasingly more important at higher collider energies and for probing larger mass scales due to collinear logarithmic enhancements of the cross section. In this context, we revisit the production of a hypothetic heavy Majorana neutrino $(N)$ at hadron colliders. Particular attention is paid to the fusion process $W\\gamma \\rightarrow N\\ell^{\\pm}$. We systematically categorize the contributions from an initial state photon in the elastic, inelastic, and deeply inelastic channels. Comparing with the leading channel via the Drell-Yan production $q \\bar{q}'\\rightarrow W^{*}\\rightarrow N\\ell^{\\pm}$ at NNLO in QCD, we find that the $W\\gamma$ fusion process becomes relatively more important at higher scales, surpassing the DY mechanism at $m_{N} \\sim 1 \\text{TeV} \\ (770 \\text{GeV})$ at the 14 TeV LHC (100 TeV VLHC). We investigate the inclusive heavy Majorana neutrino signal, including QCD corrections, and quantify the Standard Model backgrounds at future hadron colliders. We conclude that, with the currently allowed mixing $| V_{\\mu N}| ^2discovery can be made via the same-sign dimuon channel for $m_N = 530 (1070)$ GeV at the 14 TeV LHC (100 TeV VLHC) after 1 ab$^{-1}$. Reversely, for $m_N = 500$ GeV and the same integrated luminosity, a mixing $| V_{\\mu N}|^2$ of the order $1.1\\times10^{-3} (2.5\\times10^{-4})$ may be probed.

  11. Higgs Hunting at the Large Hadron Collider

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-DoseOptions forHeavy-DutyHere�sHiddenDevelopmentSinjini

  12. QCD corrections to associated t anti-t h production at hadron colliders

    E-Print Network [OSTI]

    S. Dawson; L. Orr; L. Reina; D. Wackeroth

    2002-10-07

    We briefly present the status of QCD corrections to the inclusive total cross section for the production of a Higgs boson in association with a top-quark pair within the Standard Model at hadron colliders.

  13. On CP violation and the measurement of the dimuon charge asymmetry at hadron colliders

    E-Print Network [OSTI]

    B. Hoeneisen

    2006-07-26

    B factories measure the CP violation parameter of B^0 Bbar^0 mixing and decay. Hadron colliders measure the dimuon charge asymmetry of an admixture of B hadrons. In this note we discuss a subtle point on how the CP violation parameter of B^0_s Bbar^0_s mixing and decay can be extracted from these measurements.

  14. Search for a light fermiophobic Higgs boson produced via gluon fusion at hadron colliders

    SciTech Connect (OSTI)

    Arhrib, Abdesslam; Benbrik, Rachid; Guedes, R. B.; Santos, R.

    2008-10-01

    In this study, we propose new Higgs production mechanisms with multiphoton final states in the fermiophobic limit of the two Higgs doublet model. The processes are: gg{yields}hh, gg{yields}Hh followed by H{yields}hh and gg{yields}Ah followed by A{yields}hZ. In the fermiophobic limit, gg{yields}hh and gg{yields}Ah{yields}hhZ would give rise to 4{gamma} signature while gg{yields}Hh{yields}hhh can give a 6{gamma} final state. We show that both the Fermilab Tevatron and CERN's Large Hadron Collider can probe a substantial slice of the parameter space in this fermiophobic scenario of the two Higgs doublet model. If observed the above processes can give some information on the triple Higgs couplings involved.

  15. Phenomenology of Production and Decay of Spinning Extra-Dimensional Black Holes at Hadron Colliders

    E-Print Network [OSTI]

    James A. Frost; Jonathan R. Gaunt; Marco O. P. Sampaio; Marc Casals; Sam R. Dolan; M. Andrew Parker; Bryan R. Webber

    2009-10-16

    We present results of CHARYBDIS2, a new Monte Carlo simulation of black hole production and decay at hadron colliders in theories with large extra dimensions and TeV-scale gravity. The main new feature of CHARYBDIS2 is a full treatment of the spin-down phase of the decay process using the angular and energy distributions of the associated Hawking radiation. Also included are improved modelling of the loss of angular momentum and energy in the production process as well as a wider range of options for the Planck-scale termination of the decay. The new features allow us to study the effects of black hole spin and the feasibility of its observation in such theories.

  16. Effects of invisible particle emission on global inclusive variables at hadron colliders

    E-Print Network [OSTI]

    Andreas Papaefstathiou; Bryan Webber

    2010-07-23

    We examine the effects of invisible particle emission in conjunction with QCD initial state radiation (ISR) on quantities designed to probe the mass scale of new physics at hadron colliders, which involve longitudinal as well as transverse final-state momenta. This is an extension of our previous treatment, arXiv:0903.2013, of the effects of ISR on global inclusive variables. We present resummed results on the visible invariant mass distribution and compare them to parton-level Monte Carlo results for top quark and gluino pair-production at the LHC. There is good agreement as long as the visible pseudorapidity interval is large enough (eta ~ 3). The effect of invisible particle emission is small in the case of top pair production but substantial for gluino pair production. This is due mainly to the larger mass of the intermediate particles in gluino decay (squarks rather than W-bosons). We also show Monte Carlo modelling of the effects of hadronization and the underlying event. The effect of the underlying event is large but may be approximately universal.

  17. TESLA*HERA as Lepton (Photon)-Hadron Collider

    E-Print Network [OSTI]

    O. Yavas; A. K. Ciftci; S. Sultansoy

    2000-04-11

    New facilities for particle and nuclear physics research, which will be available due to constructing the TESLA linear electron-positron collider tangentially to the HERA proton ring, are discussed.

  18. Measuring the Higgs boson mass in dileptonic W-boson decays at hadron colliders

    E-Print Network [OSTI]

    Barr, Alan; Gripaios, Ben; Lester, Christopher G.

    2009-01-01

    Ju l 2 00 9 Cavendish-HEP-09/04 Measuring the Higgs boson mass in dileptonic W -boson decays at hadron colliders Alan J. Barr,1, ? Ben Gripaios,2, † and Christopher G. Lester3, ‡ 1Denys Wilkinson Building, Keble Road, Oxford, OX1 3RH, United Kingdom 2... CERN PH-TH, Geneva 23, 1211 Switzerland 3Cavendish Laboratory, Dept of Physics, JJ Thomson Avenue, Cambridge, CB3 0HE, United Kingdom (Dated: July 22, 2009) It is expected that hadron collider measurements of the Higgs boson mass using the decay h ? W...

  19. Physics and Analysis at a Hadron Collider - Searching for New Physics (2/3)

    SciTech Connect (OSTI)

    2010-01-20

    This is the second lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This second lecture discusses techniques important for analyses searching for new physics using the CDF B_s --> mu+ mu- search as a specific example. The lectures are aimed at graduate students.

  20. 2014 8 22 4:00PM-5:00PM Title: "Exploration of the Higgs boson and the Physics case for the Large Hadron Electron

    E-Print Network [OSTI]

    Wang, Yayu

    2014 8 22 4:00PM-5:00PM Title: "Exploration of the Higgs boson and the Physics case for the Large Hadron Electron Collider" Abstract: With the discovery of a Higgs boson at the Large Hadron) Prof. Mellado is an expert on the Higgs boson ­ a sub-atomic particle that is thought to give matter

  1. Physics and Analysis at a Hadron Collider - Making Measurements (3/3)

    ScienceCinema (OSTI)

    None

    2011-10-06

    This is the third lecture of three which together discuss the physics of hadron colliders with an emphasis on experimental techniques used for data analysis. This third lecture discusses techniques important for analyses making a measurement (e.g. determining a cross section or a particle property such as its mass or lifetime) using some CDF top-quark analyses as specific examples. The lectures are aimed at graduate students.

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

    SciTech Connect (OSTI)

    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.

  3. QCD Corrections to Pair Production of Type III Seesaw Leptons at Hadron Colliders

    E-Print Network [OSTI]

    Richard Ruiz

    2015-09-17

    If kinematically accessible, hadron collider experiments provide an ideal laboratory for the direct production of heavy lepton partners in Seesaw models. In the context of the Type III Seesaw Mechanism, the $\\mathcal{O}(\\alpha_s)$ rate and shape corrections are presented for the pair production of hypothetical, heavy $SU(2)_L$ triplet leptons in $pp$ collisions at $\\sqrt{s}=13,$ 14, and 100 TeV. The next-to-leading order (NLO) $K$-factors span, approximately, $K^{NLO}=1.1 - 1.4$ for both charged current and neutral current processes over a triplet mass range $m_T = 100~\\text{GeV}-2\\text{TeV}$. Total production cross sections exhibit a $^{+5\\%}_{-6\\%}$ scale dependence at 14 TeV and $\\pm1\\%$ at 100 TeV. The NLO differential $K$-factors for heavy lepton kinematics are largely flat, suggesting that na\\"ive scaling by the total $K^{NLO}$ is reasonably justified. The resummed transverse momentum distribution of the dilepton system is presented at leading logarithmic (LL) accuracy. The effects of resummation are large in TeV-scale dilepton systems. Discovery potential to heavy lepton pairs at 14 and 100 TeV is briefly explored: At the High-Luminosity LHC, we estimate a $4.8-6.3\\sigma$ discovery potential maximally for $m_T = 1.5-1.6~\\text{TeV}$ after 3000 fb$^{-1}$. With 300 (3000) fb$^{-1}$, there is $2\\sigma$ sensitivity up to $m_T = 1.3-1.4~\\text{TeV}~(1.7-1.8~\\text{TeV})$ in the individual channels. At 100 TeV and with 10 fb$^{-1}$, a $5\\sigma$ discovery can be achieved for $m_T=1.4-1.6~\\text{TeV}$.

  4. Beam Optics Studies in the Large Hadron Collider Observations on an Anomalous Octupolar Resonance Line in the LHC -- and -- Accuracy & Feasibility of the $\\beta^*$ Measurement for LHC and HL-LHC Using K-Modulation

    E-Print Network [OSTI]

    Carlier, F S

    While linear LHC dynamics are mostly understood and under control, non-linear beam dynamics will play an increasingly important role in the challenging regimes of future LHC operation. In 2012, turn-by-turn measurements of large betatron excitations of LHC Beam 2 at injection energy were carried out. These measurements revealed an unexpectedly large spectral line in the horizontal motion with frequency $-Q_x-2Q_y$. Detailed analyses and simulations are presented to understand the nature of this spectral line. -- ABSTRACT II -- The future regimes of operation of the LHC will require improved control of $\\beta^*$ measurements to succesfully level the luminosities in the interaction points. The method of K-modulation has been widely used in other machines such as, LEP, HERA, Tevatron and ALBA to measure lattice beta functions. In the LHC, K-modulation of the last quadrupoles of the IP is the method to measure $\\beta^*$ in the IP. This paper highlights the challenge of high precision tune measurements (up to $10...

  5. A Large Hadron Electron Collider at CERN (Journal Article) |...

    Office of Scientific and Technical Information (OSTI)

    M. ; Brookhaven ; Barber, D. ; Daresbury DESY Liverpool U. ; Bartels, J. ; Hamburg, Tech. U. ; Behnke, O. ; DESY ; Behr, J. ; DESY ; Belyaev, A.S. ; Rutherford...

  6. Distinguishing Spins in Decay Chains at the Large Hadron Collider

    E-Print Network [OSTI]

    Christiana Athanasiou; Christopher G. Lester; Jennifer M. Smillie; Bryan R. Webber

    2008-08-29

    If new particles are discovered at the LHC, it will be important to determine their spins in as model-independent a way as possible. We consider the case, commonly encountered in models of physics beyond the Standard Model, of a new scalar or fermion $D$ decaying sequentially into other new particles $C,B,A$ via the decay chain $D\\to C q$, $C\\to B l^{near}$, $B\\to A l^{far}$, $l^{near}$ and $l^{far}$ being opposite-sign same-flavour charged leptons and $A$ being invisible. We compute the observable 2- and 3-particle invariant mass distributions for all possible spin assignments of the new particles, and discuss their distinguishability using a quantitative measure known as the Kullback-Leibler distance.

  7. Searching for Top Squarks at the Large Hadron Collider 

    E-Print Network [OSTI]

    Wang, Kechen

    2014-08-01

    (“heavy slepton” case). The final states have at least 2 jets, 2 opposite-sign same flavor leptons and missing energy. The opposite-sign same flavor dilepton mass distribution after subtracting the opposite-sign different flavor distribution shows a clear...

  8. Establishing the Mirage Mediation Model at the Large Hadron Collider 

    E-Print Network [OSTI]

    Wang, Kechen

    2012-10-19

    of the Lower Energy Tau PT ?slope Distribution of Benchmark Point.................... 22 Figure 5 The Effective Mass M eff Distribution of Benchmark Point....................... 23 vi LIST OF TABLES... of the up-type and down-type Higgs, /), (iv) sign(?) (? is the biliear Higgs coupling constant), (v) ni (modular weights of matter fields and Higgs fields), (vi) la (specifying how the visible sector is constructed). I assumed ? > 0...

  9. First Beam for Large Hadron Collider | Department of Energy

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRD Report to CongressApril 6,Final9Reportjobs can0 3:00PM

  10. ALCF helps tackle the Large Hadron Collider's big data challenge |

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail.Theory of rare Kaonforsupernovae2 Publications6 SmartInformation A to

  11. The Very Large Hadron Collider: The farthest energy frontier (Conference) |

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofThe MaximumReport)elastase-2;

  12. The Very Large Hadron Collider: The farthest energy frontier (Conference) |

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTechtail. (Conference)FeedbackProperties ofThe MaximumReport)elastase-2;SciTech Connect

  13. Physics Reach at Future Colliders

    SciTech Connect (OSTI)

    Krawczyk, Maria [Institute of Theoretical Physics, University of Warsaw, ul. Hoz-dota 69, 00-681 Warsaw (Poland); CERN, CH-1211 Geneva 23 (Switzerland)

    2007-11-27

    The physics reach at future colliders is discussed, with focus on the Higgs sector. First we present the Standard Model and some results obtained at the existing high-energy hadron collider, Tevatron, together with the corresponding expectations for the Large Hadron Collider (LHC), which starts operating in 2008. Then we discuss important low energy measurements: the anomalous magnetic moment for muon and the leptonic B-decay together with b{yields}s{gamma}. Finally the potential of the planned e{sup +}e{sup -} International Linear Collider (ILC) and its possible option Photon Linear Collider (PLC), e{gamma} and {gamma}{gamma}, is shortly presented.

  14. Diffractive W production at hadron colliders as a test of colour singlet exchange mechanisms

    E-Print Network [OSTI]

    Gunnar Ingelman; Roman Pasechnik; Johan Rathsman; Dominik Werder

    2012-10-22

    We revisit diffractive and exclusive W production at hadron colliders in different models for soft colour exchanges. The process pp to p[WX]p, and in particular a W charge asymmetry, has been suggested as a way to discriminate diffractive processes as being due to pomeron exchange in Regge phenomenology or QCD-based colour reconnection models. Our detailed analysis of the latter models at LHC energies shows, however, that they give similar results as pomeron models for very leading protons and central W production, including a vanishing W charge asymmetry. We demonstrate that soft colour exchange models provide a continuous transition from diffractive to inelastic processes and thereby include the intrinsic asymmetry of inelastic interactions while being at the same time sensitive to the underlying hadronisation models. Such sensitivity also concerns the differential distributions in proton momentum and W transverse momentum which opens possibilities to discriminate between different colour reconnection models.

  15. A Novel method for modeling the recoil in W boson events at hadron collider

    SciTech Connect (OSTI)

    Abazov, Victor Mukhamedovich; Abbott, Braden Keim; Abolins, Maris A.; Acharya, Bannanje Sripath; Adams, Mark Raymond; Adams, Todd; Aguilo, Ernest; Ahsan, Mahsana; Alexeev, Guennadi D.; Alkhazov, Georgiy D.; Alton, Andrew K.; /Michigan U. /Augustana Coll., Sioux Falls /Northeastern U.

    2009-07-01

    We present a new method for modeling the hadronic recoil in W {yields} {ell}{nu} events produced at hadron colliders. The recoil is chosen from a library of recoils in Z {yields} {ell}{ell} data events and overlaid on a simulated W {yields} {ell}{nu} event. Implementation of this method requires that the data recoil library describe the properties of the measured recoil as a function of the true, rather than the measured, transverse momentum of the boson. We address this issue using a multidimensional Bayesian unfolding technique. We estimate the statistical and systematic uncertainties from this method for the W boson mass and width measurements assuming 1 fb{sup -1} of data from the Fermilab Tevatron. The uncertainties are found to be small and comparable to those of a more traditional parameterized recoil model. For the high precision measurements that will be possible with data from Run II of the Fermilab Tevatron and from the CERN LHC, the method presented in this paper may be advantageous, since it does not require an understanding of the measured recoil from first principles.

  16. Superconducting Magnet with the Reduced Barrel Yoke for the Hadron Future Circular Collider

    E-Print Network [OSTI]

    Klyukhin, V I; Berriaud, C; Curé, B; Dudarev, A; Gaddi, A; Gerwig, H; Hervé, A; Mentink, M; Rolando, G; Da Silva, H F Pais; Wagner, U; Kate, H H J ten

    2015-01-01

    The conceptual design study of a hadron Future Circular Collider (FCC-hh) with a center-of-mass energy of the order of 100 TeV in a new tunnel of 80-100 km circumference assumes the determination of the basic requirements for its detectors. A superconducting solenoid magnet of 12 m diameter inner bore with the central magnetic flux density of 6 T is proposed for a FCC-hh experimental setup. The coil of 24.518 m long has seven 3.5 m long modules included into one cryostat. The steel yoke with a mass of 21 kt consists of two barrel layers of 0.5 m radial thickness, and 0.7 m thick nose disk, four 0.6 m thick end-cap disks, and three 0.8 m thick muon toroid disks each side. The outer diameter of the yoke is 17.7 m; the length without the forward muon toroids is 33 m. The air gaps between the end-cap disks provide the installation of the muon chambers up to the pseudorapidity of \\pm 3.5. The conventional forward muon spectrometer provides the measuring of the muon momenta in the pseudorapidity region from \\pm 2.7...

  17. NNLO Benchmarks for Gauge and Higgs Boson Production at TeV Hadron Colliders

    E-Print Network [OSTI]

    S. Alekhin; J. Blümlein; P. Jimenez-Delgado; S. Moch; E. Reya

    2010-11-29

    The inclusive production cross sections for $W^+, W^-$ and $Z^0$-bosons form important benchmarks for the physics at hadron colliders. We perform a detailed comparison of the predictions for these standard candles based on recent next-to-next-to-leading order (NNLO) parton parameterizations and new analyses including the combined HERA data, compare to all available experimental results, and discuss the predictions for present and upcoming RHIC, SPS, Tevatron and LHC energies. The rates for gauge boson production at the LHC can be rather confidently predicted with an accuracy of better than about 10% at NNLO. We also present detailed NNLO predictions for the Higgs boson production cross sections for Tevatron and LHC energies (1.96, 7, 8, 14 TeV), and propose a possible method to monitor the gluon distribution experimentally in the kinematic region close to the mass range expected for the Higgs boson. The production cross sections of the Higgs boson at the LHC are presently predicted with an accuracy of about 10--17%. The inclusion of the NNLO contributions is mandatory for achieving such accuracies since the total uncertainties are substantially larger at NLO.

  18. Effects of QCD radiation on inclusive variables for determining the scale of new physics at hadron colliders

    E-Print Network [OSTI]

    Andreas Papaefstathiou; Bryan Webber

    2009-07-10

    We examine the effects of QCD initial-state radiation on a class of quantities, designed to probe the mass scale of new physics at hadron colliders, which involve longitudinal as well as transverse final-state momenta. In particular, we derive universal functions that relate the invariant mass and energy distribution of the visible part of the final state to that of the underlying hard subprocess. Knowledge of this relationship may assist in checking hypotheses about new processes, by providing additional information about their scales. We compare our results with those of Monte Carlo studies and find good general agreement.

  19. Physics studies at a future linear collider 

    E-Print Network [OSTI]

    Tabassam, Hajrah

    2012-06-22

    With the start of the Large Hadron Collider(LHC) at CERN, we will obtain a new understanding of the physics beyond our current limits. New discoveries will be made; but we will require a deeper understanding, which the ...

  20. The Neutrino Factory and Muon Collider Collaboration Large Underground Space

    E-Print Network [OSTI]

    McDonald, Kirk

    Kirk T. McDonald Princeton University June 26, 2001 Meeting with Brierley Associates Ithaca, NY http://puhep1.princeton.edu/~mcdonald/nufact/ Kirk T. McDonald June 26, 2001 1 #12; The Neutrino Factory for neutrino detectors. Kirk T. McDonald June 26, 2001 2 #12; The Neutrino Factory and Muon Collider

  1. Probing triple-Higgs productions via $4b2\\gamma$ at a 100 TeV hadron collider

    E-Print Network [OSTI]

    Chen, Chien-Yi; Zhao, Xiaoran; Zhong, Yi-Ming; Zhao, Zhijie

    2015-01-01

    The quartic self-coupling of the Standard Model Higgs boson can only be measured by observing the triple-Higgs production process, but it is challenging for the LHC Run 2 or ILC at a few TeV because of its extremely small production rate. In this paper, we present a detailed MC simulation study of the triple-Higgs production through gluon fusion at a 100 TeV hadron collider and explore the feasibility of observing this production mode. We focus on the decay channel $HHH\\rightarrow b\\bar{b}b\\bar{b}\\gamma\\gamma$, investigating detector effects and optimizing the kinematic cuts to discriminate the signal from the backgrounds. Our study shows that in order to observe the Standard Model triple-Higgs signal, the integrated luminosity of a 100 TeV hadron collider should be greater than $1.8\\times 10^4$ ab$^{-1}$. We also explore the dependence of the cross section upon the trilinear ($\\lambda_3$) and quartic ($\\lambda_4$) self-couplings of the Higgs. We find that, through a search in the triple Higgs production, the...

  2. Probing triple-Higgs productions via $4b2?$ at a 100 TeV hadron collider

    E-Print Network [OSTI]

    Chien-Yi Chen; Qi-Shu Yan; Xiaoran Zhao; Zhijie Zhao; Yi-Ming Zhong

    2015-10-23

    The quartic self-coupling of the Standard Model Higgs boson can only be measured by observing the triple-Higgs production process, but it is challenging for the LHC Run 2 or ILC at a few TeV because of its extremely small production rate. In this paper, we present a detailed MC simulation study of the triple-Higgs production through gluon fusion at a 100 TeV hadron collider and explore the feasibility of observing this production mode. We focus on the decay channel $HHH\\rightarrow b\\bar{b}b\\bar{b}\\gamma\\gamma$, investigating detector effects and optimizing the kinematic cuts to discriminate the signal from the backgrounds. Our study shows that in order to observe the Standard Model triple-Higgs signal, the integrated luminosity of a 100 TeV hadron collider should be greater than $1.8\\times 10^4$ ab$^{-1}$. We also explore the dependence of the cross section upon the trilinear ($\\lambda_3$) and quartic ($\\lambda_4$) self-couplings of the Higgs. We find that, through a search in the triple Higgs production, the parameters $\\lambda_3$ and $\\lambda_4$ can be restricted to the ranges $[-1, 5]$ and $[-20, 30]$, respectively. We also examine how new physics can change the production rate of triple-Higgs events. For example, in the singlet extension of the Standard Model, we find that the triple-Higgs production rate can be increased by a factor of $\\mathcal{O}(10)$.

  3. Searches for dark matter signals in simplified models at future hadron colliders

    E-Print Network [OSTI]

    Qian-Fei Xiang; Xiao-Jun Bi; Peng-Fei Yin; Zhao-Huan Yu

    2015-03-10

    We study the prospect of dark matter (DM) searches in the monojet channel at future $pp$ colliders with center-of-mass energies of 33, 50, and 100~TeV. We consider a class of simplified models in which a vector boson connecting DM particles to quarks is introduced. Comparing with studies in the effective field theory, the present framework gives more reasonable production rates and kinematics of the DM signatures. We estimate the sensitivities of future colliders with an integrated luminosity of 3 $ab^{-1}$ to the DM-induced monojet signature and show the parameter space that can be explored. The constraints from direct and indirect DM detection experiments are compared with the future collider sensitivities. We find that the future collider detection will be much more sensitive than the indirect detection for the vector interaction, and have better sensitivities than those of the direct detection by several orders of magnitude for the axial vector interaction.

  4. Les Houches Guidebook to Monte Carlo Generators for Hadron Collider Physics

    E-Print Network [OSTI]

    M. A. Dobbs; S. Frixione; E. Laenen; K. Tollefson; H. Baer; E. Boos; B. Cox; R. Engel; W. Giele; J. Huston; S. Ilyin; B. Kersevan; F. Krauss; Y. Kurihara; L. Lonnblad; F. Maltoni; M. Mangano; S. Odaka; P. Richardson; A. Ryd; T. Sjostrand; P. Skands; Z. Was; B. R. Webber; D. Zeppenfeld

    2004-03-05

    Recently the collider physics community has seen significant advances in the formalisms and implementations of event generators. This review is a primer of the methods commonly used for the simulation of high energy physics events at particle colliders. We provide brief descriptions, references, and links to the specific computer codes which implement the methods. The aim is to provide an overview of the available tools, allowing the reader to ascertain which tool is best for a particular application, but also making clear the limitations of each tool.

  5. A High Field Magnet Design for A Future Hadron Collider==== R. Gupta, K. Chow, D. Dietderich, S. Gourlay, G. Millos, A. McInturff, R. Scanlan

    E-Print Network [OSTI]

    Gupta, Ramesh

    A High Field Magnet Design for A Future Hadron Collider==== R. Gupta, K. Chow, D. Dietderich, S the completion of LHC. This paper presents a high field magnet design option based on Nb3Sn technology. A preliminary magnetic and mechanical design of a 14-16 T, 2-in-1 dipole based on the "common coil design

  6. 62-TeV center of mass hadron collider with superbunch beams

    SciTech Connect (OSTI)

    Ryuji Yamada et al.

    2001-11-05

    The scheme of a 62-TeV center of mass p-p collider with superbunch beams at Fermilab is proposed as a practical and realistically achievable future project. It will be built in two stages, using the same tunnel, first with a 2 Tesla low field magnet collider ring and later with a 10 Tesla high field magnet collider ring. Both low and high field magnets have twin bore aperture and will be installed in the tunnel with the circumference of 87.25 km. In each bore a proton beam is accelerated, using induction cavities to increase luminosity. In the first stage they install a 7 TeV accelerator ring with operating field of 2 Tesla, based on the superferric transmission-line design. This ring will be operated at a 14-TeV center of mass collider. This will have the same energy as the LHC, but it will have 15 times higher luminosity, namely 1.5 x 10{sup 35}/cm{sup 2}/sec. The estimated synchrotron radiation is negligible with this machine. The existing Fermilab accelerator system, including the 150 GeV main injector, will be used as the injector system. Its rough cost estimation and schedule for this first stage are presented. In the second stage proton beams are accelerated, also using induction cavities up to 31 TeV with the 10 Tesla dipole magnets. The counter circulating beams will collide with the 62-TeV center of mass energy. With the superbunch beams they can expect the luminosity can be increased about 15 times more than the conventional method with RF cavities. It will be 10{sup 35}/cm{sup 2}/sec. In the second stage, the synchrotron radiation power will be about 12 W/m, and they need an elaborated beam screen.

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

    E-Print Network [OSTI]

    Paus, Christoph M. E.

    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[superscript -1] of ...

  8. International Linear Collider Abbildung 66: Drei-dimensionale Zeichnung des LDC Large Detector Concept, das mit we-

    E-Print Network [OSTI]

    International Linear Collider Abbildung 66: Drei-dimensionale Zeichnung des LDC Large Detector weitere Kalorimeter (BeamCal und LumiCal). 134 #12;International Linear Collider International Linear Entwicklung f¨ur den e+e- International Linear Collider (ILC). Weltweit waren die Aktivit¨aten f¨ur den

  9. Performance of the Large Scale Prototypes of the CALICE Tile Hadron Calorimeter

    E-Print Network [OSTI]

    Reinecke, M

    2015-01-01

    The concept of a tile hadron calorimeter (HCAL) for the International Linear Collider (ILC) has been developed. A major aspect is the improvement of the jet energy resolution by measuring details of the shower development and combining them with the data of the tracking chamber (particle flow). The concept utilizes scintillating tiles that are read out by novel Silicon Photomultipliers (SiPMs) and takes into account all design aspects that are demanded by the intended operation

  10. Development of Large Area Gas Electron Multiplier Detector and...

    Office of Scientific and Technical Information (OSTI)

    Development of Large Area Gas Electron Multiplier Detector and Its Application to a Digital Hadron Calorimeter for Future Collider Experiments Citation Details In-Document Search...

  11. Hadronization

    E-Print Network [OSTI]

    Bryan Webber

    1994-11-30

    Hadronization corrections to the predictions of perturbative QCD are reviewed. The existing models for the conversion of quarks and gluons into hadrons are summarized. The most successful models give a good description of the data on $e^+e^-$ event shapes and jet fragmentation functions, and suggest that the dominant hadronization effects have a $1/Q$ dependence on the hard process energy scale $Q$. In several cases the $1/Q$ terms can be understood in terms of a simple longitudinal phase-space model. They can also be inferred by relating non-perturbative renormalon effects to the infrared cutoff dependence of perturbative contributions.

  12. Energy range of hadronic calorimeter towers and cells for high-pT jets at a 100 TeV collider

    E-Print Network [OSTI]

    S. V. Chekanov; J. Dull

    2015-12-28

    This paper discusses a study of tower and cell energy ranges of a hadronic calorimeter for a 100 TeV pp collider. The dynamic energy ranges were estimated using Standard Model jets with transverse momenta above 20 TeV. The simulations were performed using the PYTHIA Monte Carlo model after a fast detector simulation tuned to the ATLAS hadronic calorimeter. We estimate the maximum energy range of towers and cells as a function of lateral cell sizes for several extreme cases of jet transverse energy.

  13. Energy range of hadronic calorimeter towers and cells for high-pT jets at a 100 TeV collider

    E-Print Network [OSTI]

    S. V. Chekanov; J. Dull

    2015-11-04

    This paper discusses a study of tower and cell energy ranges of a hadronic calorimeter for a 100 TeV pp collider. The dynamic energy ranges were estimated using Standard Model jets with transverse momenta above 20 TeV. The simulations were performed using the PYTHIA Monte Carlo model after a fast detector simulation tuned to the ATLAS hadronic calorimeter. We estimate the maximum energy range of towers and cells as a function of lateral cell sizes for several extreme cases of jet transverse energy.

  14. The Working Group M5 on Lepton-Hadron Colliders Conveners: Ilan Ben-Zvi and Georg H. Hoffstaetter

    E-Print Network [OSTI]

    Hoffstaetter, Georg

    ........................................................................... 28 3. eRHIC, Electron-Hadron Collisions with RHIC

  15. Pair Production of Heavy Quarkonium and $B_c(^*)$ Mesons at Hadron Colliders

    E-Print Network [OSTI]

    Rong Li; Yu-Jie Zhang; Kuang-Ta Chao

    2009-03-12

    We investigate the pair production of S-wave heavy quarkonium at the LHC in the color-singlet mechanism (CSM) and estimate the contribution from the gluon fragmentation process in the color-octet mechanism (COM) for comparison. With the matrix elements extracted previously in the leading order calculations, the numerical results show that the production rates are quite large for the pair production processes at the LHC. The $p_t$ distribution of double $J/\\psi$ production in the CSM is dominant over that in the COM when $p_t$ is smaller than about 8GeV. For the production of double $\\Upsilon$, the contribution of the COM is always larger than that in the CSM. The large differences in the theoretical predictions between the CSM and COM for the $p_t$ distributions in the large $p_t$ region are useful in clarifying the effects of COM on the quarkonium production. We also investigate the pair production of S-wave $B_c$ and $B_c^*$ mesons, and the measurement of these processes is useful to test the CSM and extract the LDMEs for the $B_c$ and $B_c^*$ mesons.

  16. The Higgs Physics Programme at the International Linear Collider

    E-Print Network [OSTI]

    Felix Sefkow

    2014-10-13

    The talk summarises the case for Higgs physics in $e^+e^-$ collisions and explains how Higgs parameters can be extracted in a model-independent way at the International Linear Collider (ILC). The expected precision will be discussed in the context of projections for the experiments at the Large Hadron Collider (LHC).

  17. The Higgs Physics Programme at the International Linear Collider

    E-Print Network [OSTI]

    Sefkow, Felix

    2014-01-01

    The talk summarises the case for Higgs physics in $e^+e^-$ collisions and explains how Higgs parameters can be extracted in a model-independent way at the International Linear Collider (ILC). The expected precision will be discussed in the context of projections for the experiments at the Large Hadron Collider (LHC).

  18. Scaling properties of inclusive W$^\\pm$ production at hadron colliders

    E-Print Network [OSTI]

    Arleo, François; Paukkunen, Hannu

    2015-01-01

    We consider the hadroproduction of W gauge bosons in their leptonic decay mode. Starting from the leading-order expressions, we show that by defining a suitable scaling variable the center-of-mass dependence of the cross sections at the LHC energies can be essentially described by a simple power law. The scaling exponent is directly linked to the small-$x$ behaviour of quark distributions which, at the high virtualities involved in W production, is largely dictated by QCD parton evolution. This entails a particularly simple scaling law for the lepton charge asymmetry and also predicts that measurements in different collision systems (p-p, p-$\\overline{\\rm p}$, p-Pb Pb-Pb) are straightforwardly related. The expectations are compared with the existing data and a very good overall agreement is observed. A precision observable that can be measured at the LHC is proposed.

  19. Scaling properties of inclusive W$^\\pm$ production at hadron colliders

    E-Print Network [OSTI]

    François Arleo; Émilien Chapon; Hannu Paukkunen

    2015-09-14

    We consider the hadroproduction of W gauge bosons in their leptonic decay mode. Starting from the leading-order expressions, we show that by defining a suitable scaling variable the center-of-mass dependence of the cross sections at the LHC energies can be essentially described by a simple power law. The scaling exponent is directly linked to the small-$x$ behaviour of quark distributions which, at the high virtualities involved in W production, is largely dictated by QCD parton evolution. This entails a particularly simple scaling law for the lepton charge asymmetry and also predicts that measurements in different collision systems (p-p, p-$\\overline{\\rm p}$, p-Pb Pb-Pb) are straightforwardly related. The expectations are compared with the existing data and a very good overall agreement is observed. A precision observable that can be measured at the LHC is proposed.

  20. Spin rotation and depolarization of high-energy particles in crystals at Hadron Collider (LHC) and Future Circular Collider (FCC) energies and the possibility to measure the anomalous magnetic moments of short-lived particles

    E-Print Network [OSTI]

    Baryshevsky, V G

    2015-01-01

    We study the phenomena of spin rotation and depolarization of high-energy particles in crystals in the range of high energies that will be available at Hadron Collider (LHC) and Future Circular Collider (FCC). It is shown that these phenomena can be used to measure the anomalous magnetic moments of short-lived particles in this range of energies. We also demonstrate that the phenomenon of particle spin depolarization in crystals provides a unique possibility of measuring the anomalous magnetic moment of negatively-charged particles (e.g., beauty baryons), for which the channeling effect is hampered due to far more rapid dechanneling as compared to that for positively-charged particles. Channeling of particles in either straight or bent crystals with polarized nuclei could be used for polarization and the analysis thereof of high-energy particles.

  1. Spin rotation and depolarization of high-energy particles in crystals at Hadron Collider (LHC) and Future Circular Collider (FCC) energies and the possibility to measure the anomalous magnetic moments of short-lived particles

    E-Print Network [OSTI]

    V. G. Baryshevsky

    2015-04-25

    We study the phenomena of spin rotation and depolarization of high-energy particles in crystals in the range of high energies that will be available at Hadron Collider (LHC) and Future Circular Collider (FCC). It is shown that these phenomena can be used to measure the anomalous magnetic moments of short-lived particles in this range of energies. We also demonstrate that the phenomenon of particle spin depolarization in crystals provides a unique possibility of measuring the anomalous magnetic moment of negatively-charged particles (e.g., beauty baryons), for which the channeling effect is hampered due to far more rapid dechanneling as compared to that for positively-charged particles. Channeling of particles in either straight or bent crystals with polarized nuclei could be used for polarization and the analysis thereof of high-energy particles.

  2. Distinguishing Spins in Supersymmetric and Universal Extra Dimension Models at the Large Hadron Collider

    E-Print Network [OSTI]

    Jennifer M. Smillie; Bryan R. Webber

    2007-02-21

    An interesting alternative to supersymmetry (SUSY) for extending physics beyond the Standard Model is a model with universal extra dimensions (UED), in which the SUSY superpartners are replaced by Kaluza-Klein excitations of the Standard Model particles. If new particles are discovered at the LHC, even if their mass spectrum favours SUSY or UED, it will be vital to distinguish between their spin assignments in the two models as far as possible. We extend the method proposed by Barr [hep-ph/0405052] to the UED case and investigate the angular and charge asymmetries of decay distributions for sample mass spectra of both SUSY and UED types. For hierarchical (`SUSY-type') mass spectra there is a good chance of distinguishing the spin structures of the two models. However, a mass spectrum of the quasi-degenerate type expected in UED would make it difficult to observe spin correlations.

  3. Addendum to "Distinguishing Spins in Decay Chains at the Large Hadron Collider"

    E-Print Network [OSTI]

    Christiana Athanasiou; Christopher G. Lester; Jennifer M. Smillie; Bryan R. Webber

    2006-06-20

    We extend our earlier study of spin correlations in the decay chain $D\\to C q$, $C\\to B l^{near}$, $B\\to A l^{far}$, where $A,B,C,D$ are new particles with known masses but undetermined spins, $l^{near}$ and $l^{far}$ are opposite-sign same-flavour charged leptons and $A$ is invisible. Instead of looking at the observable 2- and 3-particle invariant mass distributions separately, we compare the full three-dimensional phase space distributions for all possible spin assignments of the new particles, and show that this enhances their distinguishability using a quantitative measure known as the Kullback-Leibler distance.

  4. Charged Higgs boson in the $W^\\pm$ Higgs channel at the Large Hadron Collider

    E-Print Network [OSTI]

    Rikard Enberg; William Klemm; Stefano Moretti; Shoaib Munir; Glenn Wouda

    2015-02-14

    In light of the recent discovery of a neutral Higgs boson, $H_{\\rm obs}$, with a mass near 125 GeV, we reassess the LHC discovery potential of a charged Higgs boson, $H^\\pm$, in the $W^\\pm H_{\\rm obs}$ decay channel. This decay channel can be particularly important for a $H^\\pm$ heavier than the top quark, when it is produced through the $pp \\rightarrow tH^\\pm$ process. The knowledge of the mass of $H_{\\rm obs}$ provides an additional handle in the kinematic selection when reconstructing a Breit-Wigner resonance in the $H_{\\rm obs} \\rightarrow b\\bar{b}$ decay channel. We consider some extensions of the Standard Model Higgs sector, with and without supersymmetry, and perform a dedicated signal-to-background analysis to test the scope of this channel for the LHC running at the design energy (14 TeV), for 300/fb (standard) and 3000/fb (high) integrated luminosities. We find that, while this channel does not show much promise for a supersymmetric $H^\\pm$ state, significant portions of the parameter spaces of several two-Higgs doublet models are testable.

  5. A Nuclear Physics Program at the ATLAS Experiment at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    S. Aronson; K. Assamagan; H. Gordon; M. Leite; M. Levine; P. Nevski; H. Takai; S. White; B. Cole; J. L. Nagle

    2002-12-13

    The ATLAS collaboration has significant interest in the physics of ultra-relativistic heavy ion collisions. We submitted a Letter of Intent to the United States Department of Energy in March 2002. The following document is a slightly modified version of that LOI. More details are available at: http://atlas.web.cern.ch/Atlas/GROUPS/PHYSICS/SM/ions

  6. U.S. scientists celebrate the restart of the Large Hadron Collider...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    A highlight of the LHCs first run, which began in 2009, was the discovery of the Higgs boson, the last in the suite of elementary particles that make up scientists best picture...

  7. Search for Signatures of Extra Dimensions in the Diphoton Mass Spectrum at the Large Hadron Collider

    E-Print Network [OSTI]

    Bauer, Gerry P.

    A search for signatures of extra spatial dimensions in the diphoton invariant-mass spectrum has been performed with the CMS detector at the LHC. No excess of events above the standard model expectation is observed using a ...

  8. Minimum Bias Measurements with the ATLAS Detector at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Leyton, Michael A.

    2009-01-01

    CD-0002, CERN, Geneva, Switzerland, 2006. [119] M. Leyton.Report ATL-IP-QA-0026, CERN, Geneva, Switzerland, 2007.LHCC/98-4, CERN, Geneva, Switzerland, 1998. Technical Report

  9. Large Hadron Collider probe of supersymmetric neutrinoless double beta decay mechanism

    E-Print Network [OSTI]

    B. C. Allanach; C. H. Kom; H. Päs

    2009-02-26

    In the minimal supersymmetric extension to the Standard Model, a non-zero lepton number violating coupling lambda'_111 predicts both neutrinoless double beta decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next generation of experiments, there exist good prospects to observe single slepton production at the LHC. Neutrinoless double beta decay could otherwise result from a different source (such as a non-zero Majorana neutrino mass). Resonant single slepton production at the LHC can therefore discriminate between the lambda'_111 neutrinoless double beta decay mechanism and others.

  10. Large Hadron Collider Probe of Supersymmetric Neutrinoless Double-Beta-Decay Mechanism

    SciTech Connect (OSTI)

    Allanach, B. C.; Kom, C. H.; Paes, H. [DAMTP, University of Cambridge, Wilberforce Road, Cambridge, CB3 0WA (United Kingdom); Cavendish Laboratory, J. J. Thomson Avenue, Cambridge CB3 0HE (United Kingdom); Fakultaet fuer Physik, Technische Universitaet Dortmund, D-44221, Dortmund (Germany)

    2009-08-28

    In the minimal supersymmetric extension to the standard model, a nonzero lepton number violating coupling {lambda}{sub 111}{sup '} predicts both neutrinoless double-beta-decay and resonant single slepton production at the LHC. We show that, in this case, if neutrinoless double beta decay is discovered in the next generation of experiments, there exist good prospects to observe single slepton production at the LHC. Neutrinoless double beta decay could otherwise result from a different source (such as a nonzero Majorana neutrino mass). Resonant single slepton production at the LHC can therefore discriminate between the {lambda}{sub 111}{sup '} neutrinoless double-beta-decay mechanism and others.

  11. The upgraded Pixel Detector of the ATLAS Experiment for Run2 at the Large Hadron Collider

    E-Print Network [OSTI]

    Mullier, Geoffrey Andre; The ATLAS collaboration

    2015-01-01

    The Pixel Detector of the ATLAS experiment has shown excellent performance during the whole Run-1 of LHC. Taking advantage of the long showdown, the detector was extracted from the experiment and brought to surface, to equip it with new service quarter panels, to repair modules and to ease installation of the Insertable B-Layer (IBL), a fourth layer of pixel detectors, installed in May 2014 between the existing Pixel Detector and a new smaller radius beam-pipe at a radius of 3.3 cm. To cope with the high radiation and increased pixel occupancy due to the proximity to the interaction point, two different silicon sensor technologies (planar and 3D) have been developed. A new readout chip has been developed within CMOS 130nm technology with larger area, smaller pixel size and faster readout capability. Dedicated design features in combination with a new composite material were considered and used in order to reduce the material budget of the support structure while keeping the optimal thermo-mechanical performan...

  12. Reliability of Beam Loss Monitor Systems for the Large Hadron Collider

    E-Print Network [OSTI]

    Guaglio, Gianluca; Santoni, C

    2005-01-01

    The increase of beam energy and beam intensity, together with the use of super conducting magnets, opens new failure scenarios and brings new criticalities for the whole accelerator protection system. For the LHC beam loss protection system, the failure rate and the availability requirements have been evaluated using the Safety Integrity Level (SIL) approach. A downtime cost evaluation is used as input for the SIL approach. The most critical systems, which contribute to the final SIL value, are the dump system, the interlock system, the beam loss monitors system, and the energy monitor system. The Beam Loss Monitors System (BLMS) is critical for short and intense particles losses at 7 TeV and assisted by the Fast Beam Current Decay Monitors at 450 GeV. At medium and higher loss time it is assisted by other systems, such as the quench protection system and the cryogenic system. For BLMS, hardware and software have been evaluated in detail. The reliability input figures have been collected using historical data...

  13. Reliability of Beam Loss Monitor Systems for the Large Hadron Collider

    SciTech Connect (OSTI)

    Guaglio, G.; Dehning, B.; Santoni, C.

    2005-06-08

    The increase of beam energy and beam intensity, together with the use of super conducting magnets, opens new failure scenarios and brings new criticalities for the whole accelerator protection system. For the LHC beam loss protection system, the failure rate and the availability requirements have been evaluated using the Safety Integrity Level (SIL) approach. A downtime cost evaluation is used as input for the SIL approach. The most critical systems, which contribute to the final SIL value, are the dump system, the interlock system, the beam loss monitors system, and the energy monitor system. The Beam Loss Monitors System (BLMS) is critical for short and intense particles losses at 7 TeV and assisted by the Fast Beam Current Decay Monitors at 450 GeV. At medium and higher loss time it is assisted by other systems, such as the quench protection system and the cryogenic system. For BLMS, hardware and software have been evaluated in detail. The reliability input figures have been collected using historical data from the SPS, using temperature and radiation damage experimental data as well as using standard databases. All the data has been processed by reliability software (Isograph). The analysis spaces from the components data to the system configuration.

  14. Properties of Jets Measured with Charged Particles with the ATLAS Detector at the Large Hadron Collider

    E-Print Network [OSTI]

    Zenz, Seth Conrad

    2011-01-01

    Tracking Efficiencies and Distributions . . . . . . . Jet6 Results and Discussion 6.1 Charged particle jet crossand multiplicity in jets . . . . . . . . . . 7 Conclusions

  15. Minimum Bias Measurements with the ATLAS Detector at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Leyton, Michael A.

    2009-01-01

    Pixel DCS Hardware. Technical Report ATL-IP- CD-0002, CERN,ATLAS Pixel Detector. Technical Report ATL-IP-QA-0026, CERN,Switzerland, 1998. Technical Report BIBLIOGRAPHY [10] LHCb

  16. June 30, 2008: US portion of Large Hadron Collider completed | Department

    Broader source: Energy.gov (indexed) [DOE]

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of Natural GasAdjustmentsShirleyEnergy A plug-inPPLforLDRDEnergy CopyrightsRoomRussianJonathanJune 13,Nowof Energy

  17. Non-Large Hadron Collider Physics Program at CERN (Conference) | SciTech

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfateSciTech Connect Nanomechanical switch for|

  18. SCIENCE ON SATURDAY- "The Large Hadron Collider: big science for big

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity ofkandz-cm11 Outreach Home RoomPreservation of Fe(II) byMultidayAlumni > The EnergyRyan

  19. The International Linear Collider

    E-Print Network [OSTI]

    Barish, Barry

    2013-01-01

    In this article, we describe the key features of the recently completed technical design for the International Linear Collider (ILC), a 200-500 GeV linear electron-positron collider (expandable to 1 TeV) that is based on 1.3 GHz superconducting radio-frequency (SCRF) technology. The machine parameters and detector characteristics have been chosen to complement the Large Hadron Collider physics, including the discovery of the Higgs boson, and to further exploit this new particle physics energy frontier with a precision instrument. The linear collider design is the result of nearly twenty years of R&D, resulting in a mature conceptual design for the ILC project that reflects an international consensus. We summarize the physics goals and capability of the ILC, the enabling R&D and resulting accelerator design, as well as the concepts for two complementary detectors. The ILC is technically ready to be proposed and built as a next generation lepton collider, perhaps to be built in stages beginning as a Hig...

  20. On the Future High Energy Colliders

    E-Print Network [OSTI]

    Shiltsev, Vladimir

    2015-01-01

    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.

  1. On the Future High Energy Colliders

    E-Print Network [OSTI]

    Vladimir Shiltsev

    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.

  2. Klystron switching power supplies for the Internation Linear Collider

    SciTech Connect (OSTI)

    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.

  3. Model-Independent Measurement of the e+e– --> HZ Cross Section at a Future e+e– Linear Collider using Hadronic Z Decays

    E-Print Network [OSTI]

    AUTHOR|(SzGeCERN)435733

    2015-01-01

    A future e+e collider, such as the ILC or CLIC, would allow the Higgs sector to be probed with a precision significantly beyond that achievable at the High-Luminosity LHC. A central part of the Higgs programme at an e+e collider is the model-independent determination of the absolute Higgs couplings to fermions and to gauge bosons. Here the measurement of the e+e --> HZ Higgsstrahlung cross sec- tion, using the recoil mass technique, sets the absolute scale for all Higgs coupling measurements. Previous studies have considered s (e+e --> HZ) with Z --> l+l-, where l = e, ?. In this paper it is shown for the first time that a near model- independent recoil mass technique can be extended to the hadronic decays of the Z boson. Because the branching ratio for Z --> qq is approximately ten times greater than for Z --> l+l-, this method is statistically more powerful than using the leptonic decays. For an integrated luminosity of 500 fb-1 at a centre-of-mass energy of ps = 350 GeV at CLIC, s (e+e --> HZ) can be meas...

  4. Model-Independent Measurement of the e+e- -> HZ Cross Section at a Future e+e- Linear Collider using Hadronic Z Decays

    E-Print Network [OSTI]

    Thomson, Mark

    2015-01-01

    A future e+e- collider, such as the ILC or CLIC, would allow the Higgs sector to be probed with a precision significantly beyond that achievable at the High-Luminosity LHC. A central part of the Higgs programme at an e+e- collider is the model-independent determination of the absolute Higgs couplings to fermions and to gauge bosons. Here the measurement of the e+e-->HZ Higgsstrahlung cross section, using the recoil mass technique, sets the absolute scale for all Higgs coupling measurements. Previous studies have considered e+e- ->ZH with Z->l+l-, where l = electron or muon. In this paper it is shown for the first time that a near model-independent recoil mass technique can be extended to the hadronic decays of the Z boson. Because the branching ratio for Z->qq is approximately ten times greater than for Z->l+l-, this method is statistically more powerful than using the leptonic decays. For an integrated luminosity of 500 fb-1 at a centre-of-mass energy of 350 GeV at CLIC, the e+e-->HZ cross section can be mea...

  5. The Design of a Large Booster Ring for the Medium Energy Electron-Ion Collider at Jlab

    SciTech Connect (OSTI)

    Edward Nissen, Todd Satogata, Yuhong Zhang

    2012-07-01

    In this paper, we present the current design of the large booster ring for the Medium energy Electron-Ion Collider at Jefferson Lab. The booster ring takes 3 GeV protons or ions of equivalent rigidity from a pre-booster ring, and accelerates them to 20 GeV for protons or equivalent energy for light to heavy ions before sending them to the ion collider ring. The present design calls for a figure-8 shape of the ring for superior preservation of ion polarization. The ring is made of warm magnets and shares a tunnel with the two collider rings. Acceleration is achieved by warm RF systems. The linear optics has been designed with the transition energy above the highest beam energy in the ring so crossing of transition energy will be avoided. Preliminary beam dynamics studies including chromaticity compensation are presented in this paper.

  6. The Higgs boson and the International Linear Collider

    E-Print Network [OSTI]

    Borzumati, Francesca

    2014-01-01

    The Higgs boson will be subject of intense experimental searches in future high-energy experiments. In addition to the effort made at the Large Hadron Collider, where it was discovered, it will be the major subject of study at the International Linear Collider. We review here the reasons for that and some of the issues to be tackled at this future accelerator, in particular that of the precision of the Higgs-boson couplings.

  7. The Higgs boson and the International Linear Collider

    E-Print Network [OSTI]

    Francesca Borzumati; Eriko Kato

    2014-07-08

    The Higgs boson will be subject of intense experimental searches in future high-energy experiments. In addition to the effort made at the Large Hadron Collider, where it was discovered, it will be the major subject of study at the International Linear Collider. We review here the reasons for that and some of the issues to be tackled at this future accelerator, in particular that of the precision of the Higgs-boson couplings.

  8. Rare b hadron decays at the LHC

    E-Print Network [OSTI]

    Blake, T; Hiller, G

    2015-01-01

    With the completion of Run~I of the CERN Large Hadron Collider, particle physics has entered a new era. The production of unprecedented numbers of heavy-flavoured hadrons in high energy proton-proton collisions allows detailed studies of flavour-changing processes. The increasingly precise measurements allow to probe the Standard Model with a new level of accuracy. Rare $b$ hadron decays provide some of the most promising approaches for such tests, since there are several observables which can be cleanly interpreted from a theoretical viewpoint. In this article, the status and prospects in this field are reviewed, with a focus on precision measurements and null tests.

  9. Light vector meson photoproduction in hadron-hadron and nucleus-nucleus collisions at the energies available at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    G. Sampaio dos Santos; M. V. T. Machado

    2015-01-30

    In this work we analyse the theoretical uncertainties on the predictions for the photoproduction of light vector mesons in coherent pp, pA and AA collisions at the LHC energies using the color dipole approach. In particular, we present our predictions for the rapidity distribution for rh0 and phi photoproduction and perform an analysis on the uncertainties associated to the choice of vector meson wavefunctionand the phenomenological models for the dipole cross section. Comparison is done with the recent ALICE analysis on coherent production of rho at 2.76 TeV in PbPb collisions.

  10. Radiative return capabilities of a high-energy, high-luminositye+e-collider

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Karliner, Marek; Low, Matthew; Rosner, Jonathan L.; Wang, Lian-Tao

    2015-08-14

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

  11. Tevatron Collider Program - Physics, Results, Future?

    E-Print Network [OSTI]

    Krzysztof Sliwa

    2012-01-03

    An overview of more than 25 years of the Tevatron Collider program at Fermi National Accelerator Laboratory in Batavia, near Chicago, Illinois, USA, is presented. The physics goals of the program itself, the Tevatron accelerator design characteristics and some of its achievements are described. A selected set of the past and ongoing physics analyses and measurements performed by CDF and D0 collaborations are summarized. Also, in view of the modified plans and schedule of the Large Hadron Collider (LHC) at CERN, the future of the Tevatron program is discussed.

  12. Collider signature of T-quarks

    SciTech Connect (OSTI)

    Carena, Marcela; Hubisz, Jay; /Fermilab; Perelstein, Maxim; /Cornell U., LEPP; Verdier, Patrice; /Lyon, IPN

    2006-10-01

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

  13. arXiv:hep-ph/010131629Jan2001 QCD Signatures of Narrow Graviton Resonances in Hadron Colliders

    E-Print Network [OSTI]

    Sjöstrand, Torbjörn

    production. For the cross sections (a) and (b) of the processes depicted in Fig. 1 we reproduce in accordance? spectrum yields valu- able information for the test of models for the production of narrow graviton-Sundrum model 1]. As opposed to the concept of Large Extra Dimensions 2], where a continuous spectrum of Kaluza

  14. Quantifying jet transport properties via large $p_T$ hadron productions at NLO

    E-Print Network [OSTI]

    Zhi-Quan Liu; Hanzhong Zhang; Ben-Wei Zhang; Enke Wang

    2015-10-08

    Nuclear modification factor $R_{AA}$ for large $p_T$ single hadron is studied in a next-to-leading order (NLO) perturbative QCD (pQCD) parton model with medium-modified fragmentation functions (mFFs) due to jet quenching in high-energy heavy-ion collisions. The energy loss of the hard partons in the QGP is incorporated in the mFFs which utilize two most important parameters to characterize the transport properties of the hard parton jets: the jet transport parameter $\\hat q_{0}$ and the mean free path $\\lambda_{0}$, both at the initial time $\\tau_0$. A phenomenological study of the experimental data for $R_{AA}(p_{T})$ is performed to constrain the two parameters with simultaneous $\\chi^2/{\\rm d.o.f}$ fits to RHIC as well as LHC data. We obtain for energetic quarks $\\hat q_{0}\\approx 1.1 \\pm 0.2$ GeV$^2$/fm and $\\lambda_{0}\\approx 0.4 \\pm 0.03$ fm in central $Au+Au$ collisions at $\\sqrt{s_{NN}}=200$ GeV, while $\\hat q_{0}\\approx 1.7 \\pm 0.3$ GeV$^2$/fm, and $\\lambda_{0}\\approx 0.5 \\pm 0.05$ fm in central $Pb+Pb$ collisions at $\\sqrt{s_{NN}}=2.76$ TeV. Numerical analysis shows that the best fit happens between single scattering limit and multiple scattering limit for the energetic jets propagating through the bulk medium. Based on the best constraints for $\\lambda_{0}$ and $\\tau_0$, the estimated value for the mean-squared transverse momentum broadening is moderate which implies that the hard jets go through the medium with small reflection.

  15. Hadron Colliders Working Group Report

    SciTech Connect (OSTI)

    S. Peggs and M.J. Syphers

    2001-11-08

    The ''point design'' studied this year shows that a staged VLHC (40, {approx} 200 TeV) is feasible, with no insurmountable challenges. Further work can provide a more optimized design, by studying various alternative field strengths (e.g., superferric magnets for Stage 1) for improvements to vacuum, wall impedance, and other major performance parameters. It may be that a ''single-stage'' scenario for accessing higher energies sooner is the correct approach. A next-step design study should be considered to look at the two cases near to and complementary to the 2001 VLHC Design Study. The effectiveness of photon stops and their engineering design need to be addressed in the near future to truly determine if these devices can lead this effort to even higher luminosities and energies. The superbunch approach should continue to be studied, as well as IR designs, new instrumentation and diagnostics, and beam dynamics issues. Finally, a well organized VLHC-motivated beam studies effort should become part of the national program.

  16. Triphoton production at hadron colliders

    SciTech Connect (OSTI)

    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.

  17. Crystal Ball: On the Future High Energy Colliders

    E-Print Network [OSTI]

    Shiltsev, Vladimir

    2015-01-01

    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 ...

  18. From the Proton Synchroton to the Large Hadron Collider - 50 Years of Nobel Memories in High-Energy Physics

    ScienceCinema (OSTI)

    None

    2011-10-06

    The seminars will be held in the Main Auditorium with transmission to : Council Chamber, IT Auditorium, Prévessin BE Auditorium , Kjell Johnssen Auditorium in Building 30, Room 40-S2-A01, and via webcast. Confirmed Speakers include: Prof. Jack Steinberger, Dr. Guenther Plass, Prof. Emilio Picasso, Dr. Steve Myers, Prof. Carlo Rubbia, Prof. Burton Richter, Dr. Lyndon Evans, Prof. Rolf-Dieter Heuer, Prof. Leon Lederman, Prof. Jim Cronin, Prof. Sheldon Glashow, Prof. Jerome Friedman, Prof. Frank Wilczek, Prof. Martinus Veltman, Prof. Gerardus 't Hooft, Prof. David Gross, Prof. Samuel Ting, Prof. Steven Weinberg (via teleconference) --- Contact: Directorate.Office@cern.ch

  19. A Silicon Strip Detector for the Phase II High Luminosity Upgrade of the ATLAS Detector at the Large Hadron Collider

    E-Print Network [OSTI]

    Carlos García-Argos

    2015-01-13

    This thesis presents the work carried out in the testing of the ATLAS Phase-II Upgrade electronic systems in the future strips tracker after 2023, to be installed for operations in the HL-LHC period. The high luminosity and number of interactions per crossing that will happen after the HL-LHC starts require a complete replacement of the ATLAS tracker. The systems that have been defined for the Phase-II Upgrade will be designed to cope with that increased radiation and have the right granularity to maintain the performance with higher pile-up. In this thesis I present results on single modules and larger structures comprising multiple modules. In the context of the current ATLAS Semiconductor Tracker studies, I present an analysis of the data taken by the detector from the beginning of operation in 2010 until the first Long Shut-down in 2013. The analysis consists of an energy loss study in the Semiconductor Tracker, a task the detector was not designed to perform. However, the availability of the Time-over-Threshold of the signals generated by particles traversing the detector elements allows an estimation of the charge deposited by the particles. This calculation of the energy loss is typically used to perform particle identification, a feature that is usually not required from the tracker. In addition, I present a study that proposes the use of this energy loss calculation as a means of tracking radiation damage in the silicon.

  20. nature physics | VOL 6 | DECEMBER 2010 | www.nature.com/naturephysics 925 CERN's Large Hadron Collider has passed

    E-Print Network [OSTI]

    Loss, Daniel

    winter shut-down, possibly at an increased beam energy of 4 TeV. An extensive period of shut-down by the LHC, but as the LHC will really only hit the heights after its 2012/2013 shut-down period, the planned emerge at once from the meltdown of the two lead ions. The intention is to study the formation of quark

  1. nature physics | VOL 3 | DECEMBER 2007 | www.nature.com/naturephysics 823 The Large Hadron Collider is almost

    E-Print Network [OSTI]

    Loss, Daniel

    . And as the year comes full-circle, here's to physics from the LHC in 2008. References 1. House of Commons a steep one at that) has already been defined by the cooling, powering and then warming up of one sector

  2. 293 K - 1.9 K supporting systems for the Large Hadron Collider (LHC) cryo-magnets

    E-Print Network [OSTI]

    Mathieu, M; Renaglia, T; Rohmig, P; Williams, L R

    1998-01-01

    The LHC machine will incorporate some 2000 main ring super-conducting magnets cooled at 1.9 K by super-fluid pressurized helium, mainly 15m-long dipoles with their cryostats and 6m-long quadrupoles housed in the Short Straight Section (SSS) units. This paper presents the design of the support system of the LHC arc cryo-magnets between 1.9 K at the cold mass and 293 K at the cryostat vacuum vessel. The stringent positioning precision for magnet alignment and the high thermal performance for cryogenic efficiency are the main conflicting requirements, which have lead to a trade-off design. The systems retained for LHC are based on column-type supports positioned in the vertical plane of the magnets inside the cryostats. An ad-hoc design has been achieved both for cryo-dipoles and SSS. Each column is composed of a main tubular thin-walled structure in composite material (glass-fibre/epoxy resin, for its low thermal conductivity properties), interfaced to both magnet and cryostat via stainless steel flanges. The t...

  3. nature physics | VOL 6 | JANUARY 2010 | www.nature.com/naturephysics 1 Just as the Large Hadron Collider roared

    E-Print Network [OSTI]

    Loss, Daniel

    to better understand neutrino oscillations by firing beams of neutrinos from the High Energy Accelerator for the modelling of galaxy formation and of the climate on Earth, could also fall victim: the revitalization team Research Programme's (KEK) J-PARC accelerator complex to the Super-Kamiokande apparatus in the Kamioka mine

  4. Wideband current transformers for the surveillance of the beam extraction kicker system of the Large Hadron Collider

    E-Print Network [OSTI]

    Defrance, C; Ducimetière, L; Vossenberg, E

    2007-01-01

    The LHC beam dumping system must protect the LHC machine from damage by reliably and safely extracting and absorbing the circulating beams when requested. Two sets of 15 extraction kicker magnets form the main active part of this system. A separate high voltage pulse generator powers each magnet. Because of the high beam energy and the consequences which could result from significant beam loss due to a malfunctioning of the dump system the magnets and generators are continuously surveyed in order to generate a beam abort as soon as an internal fault is detected. Amongst these surveillance systems, wideband current transformers have been designed to detect any erratic start in one of the generators. Output power should be enough to directly re-trigger all the power trigger units of the remaining 14 generators. The current transformers were developed in collaboration with industry. To minimize losses, high-resistivity cobalt alloy was chosen for the cores. The annealing techniques originally developed for LEP b...

  5. Prospects for Colliders and Collider Physics to the 1 PeV Energy Scale

    E-Print Network [OSTI]

    B. J. King

    2000-05-04

    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 our 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+e- and hadron colliders and three muon 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&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

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

    SciTech Connect (OSTI)

    Tait, Tim (ANL) [ANL

    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.

  7. Muon Muon Collider: Feasibility Study

    SciTech Connect (OSTI)

    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. ,

    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 reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of

  8. Hadronic resonance production in d+Au collisions at root S(NN) = 200 GeV measured at the BNL Relativistic Heavy Ion Collider 

    E-Print Network [OSTI]

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Beavis, D. R.; Bellwied, R.; Benedosso, F.; Betts, R. R.; Bhardwaj, S.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bruna; Bueltmann, S.; Burton, T. P.; Bystersky, M.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Callner, J.; Catu, O.; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopdhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K. E.; Christie, W.; Chung, S. U.; Clarke, R. F.; Codrington, M. J. M.; Coffin, J. P.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; De Silva, C.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; de Souza, R. Derradi; Didenko, L.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Du, F.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Edwards, W. R.; Efimov, L. G.; Elhalhuli, E.; Elnimr, M.; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Fachini, P.; Fatemi, R.; Fedorisin, J.; Feng, A.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, Carl A.; Gaillard, L.; Gangaharan, D. R.; Ganti, M. S.; Garcia-Solis, E.; Ghazikhanian, V.; Ghosh, P.; Gorbunov, Y. N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Grube, B.; Guertin, S. M.; Guimaraes, K. S. F. F.; Gupta, A.; Gupta, N.; Guryn, W.; Haag, B.; Hallman, T. J.; Hamed, A.; Harris, J. W.; He, W.; Heinz, M.; Hepplemann, S.; Hippolyte, B.; Hirsch, A.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, H. Z.; Humanic, T. J.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jin, F.; Jones, P. G.; Joseph, J.; Judd, E. G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitan, J.; Kaplan, M.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu; Kiryluk, J.; Kisiel, A.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Krus, M.; Kuhn, C.; Kumar, L.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C. -H; LeVine, M. J.; Li, C.; Li, Y.; Lin, G.; Lin, X.; Lindenbaum, S. J.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Liu, L.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Love, W. A.; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, G. L.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mall, M. I.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Matis, H. S.; Matulenko, Yu A.; McShane, T. S.; Meschanin, A.; Millane, J.; Miller, M. L.; Minaev, N. G.; Mioduszewski, Saskia; Mischke, A.; Mishra, D. K.; Mitchell, J.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; Nepali, C.; Netrakanti, P. K.; Ng, M. J.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Okada, H.; Okorokov, V.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Planinic, M.; Pluta, J.; Poljak, N.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Reed, R.; Ridiger, A.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Roy, C.; Ruan, L.; Russcher, M. J.; Rykov, V.; Sahoo, R.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sarsour, M.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shabetai, A.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S. S.; Shi, X-H; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Staszak, D.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Y.; Sun, Z.; Surrow, B.; Symons, T. J. M.; deToledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; Tlusty; Tokarev, M.; Trainor, T. A.; Tram, V. N.; Trattner, A. L.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Leeuwen, M.; Molen, A. M. Vander; Vanfossen, J. A., Jr.; Varma, R.; Vasconcelos, G. M. S.; Vasilevski, I. M.; Vasiliev, A. N.; Videbaek, F.; Vigdor, S. E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.; Waggoner, W. T.; Wang, F.; Wang, G.; Wang, J. S.; Wang, Q.; Wang, X.

    2008-01-01

    tracker at the BNL Relativistic Heavy Ion Collider). The masses and widths of these resonances are studied as a function of transverse momentum p(T). We observe that the resonance spectra follow a generalized scaling law with the transverse mass m...

  9. Energy Dependent Growth of Nucleon and Inclusive Charged Hadron Distributions

    E-Print Network [OSTI]

    Hongmin Wang; Zhao-Yu Hou; Xian-Jing Sun

    2015-01-06

    In the Color Glass Condensate formalism, charged hadron p_{T} distributions in p+p collisions are studied by considering an energy-dependent broadening of nucleon's density distribution. Then, in the Glasma flux tube picture, the n-particle multiplicity distributions at different pseudo-rapidity ranges are investigated. Both of the theoretical results show good agreement with the recent experimental data from ALICE and CMS at \\sqrt{s}=0.9, 2.36, 7 TeV. The predictive results for p_{T} and multiplicity distributions in p+p and p+Pb collisions at the Large Hadron Collider are also given in this paper.

  10. International linear collider reference design report

    SciTech Connect (OSTI)

    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.

  11. Top quark physics in hadron collisions

    E-Print Network [OSTI]

    Wolfgang Wagner

    2007-08-03

    The top quark is the heaviest elementary particle observed to date. Its large mass makes the top quark an ideal laboratory to test predictions of perturbation theory concerning heavy quark production at hadron colliders. The top quark is also a powerful probe for new phenomena beyond the Standard Model of particle physics. In addition, the top quark mass is a crucial parameter for scrutinizing the Standard Model in electroweak precision tests and for predicting the mass of the yet unobserved Higgs boson. Ten years after the discovery of the top quark at the Fermilab Tevatron top quark physics has entered an era where detailed measurements of top quark properties are undertaken. In this review article an introduction to the phenomenology of top quark production in hadron collisions is given, the lessons learned in Tevatron Run I are summarized, and first Run II results are discussed. A brief outlook to the possibilities of top quark research a the Large Hadron Collider, currently under construction at CERN, is included.

  12. Longitudinally Polarized Photoproduction of Inclusive Hadrons Beyond the Leading Order

    E-Print Network [OSTI]

    B. Jager; M. Stratmann; W. Vogelsang

    2003-09-04

    We present a complete next-to-leading order QCD calculation for single-inclusive large-pT hadron production in longitudinally polarized lepton-nucleon collisions, consistently including ``direct'' and ``resolved'' photon contributions. This process could be studied experimentally at a future polarized lepton-proton collider like eRHIC at BNL. We examine the sensitivity of such measurements to the so far completely unknown parton content of circularly polarized photons.

  13. Longitudinally Polarized Photoproduction of Inclusive Hadrons Beyond the Leading Order

    E-Print Network [OSTI]

    Jäger, B; Vogelsang, W

    2003-01-01

    We present a complete next-to-leading order QCD calculation for single-inclusive large-pT hadron production in longitudinally polarized lepton-nucleon collisions, consistently including ``direct'' and ``resolved'' photon contributions. This process could be studied experimentally at a future polarized lepton-proton collider like eRHIC at BNL. We examine the sensitivity of such measurements to the so far completely unknown parton content of circularly polarized photons.

  14. High-Energy Physics Strategies and Future Large-Scale Projects

    E-Print Network [OSTI]

    Zimmermann, F

    2014-01-01

    We sketch the actual European and international strategies and possible future facilities. In the near term the High Energy Physics (HEP) community will fully exploit the physics potential of the Large Hadron Collider (LHC) through its high-luminosity upgrade (HL-LHC). Post-LHC options include a linear e+e- collider in Japan (ILC) or at CERN (CLIC), as well as circular lepton or hadron colliders in China (CepC/SppC) and Europe (FCC). We conclude with linear and circular acceleration approaches based on crystals, and some perspectives for the far future of accelerator-based particle physics.

  15. Large-Area Plasma-Panel Radiation Detectors for Nuclear Medicine Imaging to Homeland Security and the Super Large Hadron Collider

    E-Print Network [OSTI]

    Friedman, Peter S; Chapman, J Wehrley; Levin, Daniel S; Weaverdyck, Curtis; Zhou, Bing; Benhammou, Yan; Etzion, Erez; Moshe, M Ben; Silver, Yiftah; Beene, James R; Varner, Robert L

    2010-01-01

    A new radiation sensor derived from plasma panel display technology is introduced. It has the capability to detect ionizing and non-ionizing radiation over a wide energy range and the potential for use in many applications. The principle of operation is described and some early results presented.

  16. Large-Area Plasma-Panel Radiation Detectors for Nuclear Medicine Imaging to Homeland Security and the Super Large Hadron Collider

    E-Print Network [OSTI]

    Peter S. Friedman; Robert Ball; J. Wehrley Chapman; Daniel S. Levin; Curtis Weaverdyck; Bing Zhou; Yan Benhammou; Erez Etzion; M. Ben Moshe; Yiftah Silver; James R. Beene; Robert L. Varner Jr.

    2010-07-03

    A new radiation sensor derived from plasma panel display technology is introduced. It has the capability to detect ionizing and non-ionizing radiation over a wide energy range and the potential for use in many applications. The principle of operation is described and some early results presented.

  17. The standard model and colliders

    SciTech Connect (OSTI)

    Hinchliffe, I.

    1987-03-01

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

  18. Event simulation for colliders - A basic overview

    E-Print Network [OSTI]

    Christian Reuschle

    2014-11-26

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

  19. Impact of parton distribution function and {alpha}{sub s} uncertainties on Higgs boson production in gluon fusion at hadron colliders

    SciTech Connect (OSTI)

    Demartin, Federico; Mariani, Elisa [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano (Italy); Forte, Stefano; Vicini, Alessandro [Dipartimento di Fisica, Universita di Milano, Via Celoria 16, I-20133 Milano (Italy); INFN, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy); Rojo, Juan [INFN, Sezione di Milano, Via Celoria 16, I-20133 Milano (Italy)

    2010-07-01

    We present a systematic study of uncertainties due to parton distributions (PDFs) and the strong coupling on the gluon-fusion production cross section of the standard model Higgs at the Tevatron and LHC colliders. We compare procedures and results when three recent sets of PDFs are used, CTEQ6.6, MSTW08, and NNPDF1.2, and we discuss specifically the way PDF and strong coupling uncertainties are combined. We find that results obtained from different PDF sets are in reasonable agreement if a common value of the strong coupling is adopted. We show that the addition in quadrature of PDF and {alpha}{sub s} uncertainties provides an adequate approximation to the full result with exact error propagation. We discuss a simple recipe to determine a conservative PDF+{alpha}{sub s} uncertainty from available global parton sets, and we use it to estimate this uncertainty on the given process to be about 10% at the Tevatron and 5% at the LHC for a light Higgs.

  20. Luminosity Measurement at the International Linear Collider

    E-Print Network [OSTI]

    Iftach Sadeh

    2010-10-28

    The International Linear Collider (ILC) is a proposed electron-positron collider with a center-of-mass energy of 500~GeV, and a peak luminosity of $2 \\cdot 10^{34}~\\mathrm{cm}^{-2}\\mathrm{s}^{-1}$. The ILC will complement the Large Hadron Collider, a proton-proton accelerator, and provide precision measurements, which may help in solving some of the fundamental questions at the frontier of scientific research, such as the origin of mass and the possible existence of new principles of nature. The linear collider community has set a goal to achieve a precision of $10^{-4}$ on the luminosity measurement at the ILC. This may be accomplished by constructing a finely granulated calorimeter, which will measure Bhabha scattering at small angles. The Bhabha cross-section is theoretically known to great precision, yet the rate of Bhabha scattering events, which would be measured by the luminosity detector, will be influenced by beam-beam effects, and by the inherent energy spread of the collider. The electroweak radiative effects can be calculated to high precision and partially checked with events with final state photon radiation by distinguishing between the observable energy deposits of electrons and of photons in the luminosity calorimeter, using a clustering algorithm. In order to achieve the design goal, the geometrical parameters of the calorimeter need to be reevaluated. This must be done in a generalized manner, so as to facilitate future modifications, the need for which is foreseen, due to expected changes in the detector concept. This work demonstrates that the clustering approach is viable, and that a luminosity calorimeter may be designed to match the precision requirements on the luminosity measurement.

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

    SciTech Connect (OSTI)

    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.

  2. The International Large Detector: Letter of Intent

    E-Print Network [OSTI]

    Abe, Toshinori; Abramowicz, Halina; Adamus, Marek; Adeva, Bernardo; Afanaciev, Konstantin; Aguilar-Saavedra, Juan Antonio; Alabau Pons, Carmen; Albrecht, Hartwig; Andricek, Ladislav; Anduze, Marc; Aplin, Steve J.; Arai, Yasuo; Asano, Masaki; Attie, David; Attree, Derek J.; Burger, Jochen; Bailey, David; Balbuena, Juan Pablo; Ball, Markus; Ballin, James; Barbi, Mauricio; Barlow, Roger; Bartels, Christoph; Bartsch, Valeria; Bassignana, Daniela; Bates, Richard; Baudot, Jerome; Bechtle, Philip; Beck, Jeannine; Beckmann, Moritz; Bedjidian, Marc; Behnke, Ties; Belkadhi, Khaled; Bellerive, Alain; Bentvelsen, Stan; Bergauer, Thomas; Berggren, C.Mikael U.; Bergholz, Matthias; Bernreuther, Werner; Besancon, Marc; Besson, Auguste; Bhattacharya, Sudeb; Bhuyan, Bipul; Biebel, Otmar; Bilki, Burak; Blair, Grahame; Blumlein, Johannes; Bo, Li; Boisvert, Veronique; Bondar, A.; Bonvicini, Giovanni; Boos, Eduard; Boudry, Vincent; Bouquet, Bernard; Bouvier, Joel; Bozovic-Jelisavcic, Ivanka; Brient, Jean-Claude; Brock, Ian; Brogna, Andrea; Buchholz, Peter; Buesser, Karsten; Bulgheroni, Antonio; Butler, John; Buttar, Craig; Buzulutskov, A.F.; Caccia, Massimo; Caiazza, Stefano; Calcaterra, Alessandro; Caldwell, Allen; Callier, Stephane L.C.; Calvo Alamillo, Enrique; Campbell, Michael; Campbell, Alan J.; Cappellini, Chiara; Carloganu, Cristina; Castro, Nuno; Castro Carballo, Maria Elena; Chadeeva, Marina; Chakraborty, Dhiman; Chang, Paoti; Charpy, Alexandre; Chen, Xun; Chen, Shaomin; Chen, Hongfang; Cheon, Byunggu; Choi, Suyong; Choudhary, B.C.; Christen, Sandra; Ciborowski, Jacek; Ciobanu, Catalin; Claus, Gilles; Clerc, Catherine; Coca, Cornelia; Colas, Paul; Colijn, Auke; Colledani, Claude; Combaret, Christophe; Cornat, Remi; Cornebise, Patrick; Corriveau, Francois; Cvach, Jaroslav; Czakon, Michal; D'Ascenzo, Nicola; Da Silva, Wilfrid; Dadoun, Olivier; Dam, Mogens; Damerell, Chris; Danilov, Mikhail; Daniluk, Witold; Daubard, Guillaume; David, Dorte; David, Jacques; De Boer, Wim; De Groot, Nicolo; De Jong, Sijbrand; De Jong, Paul; De La Taille, Christophe; De Masi, Rita; De Roeck, Albert; Decotigny, David; Dehmelt, Klaus; Delagnes, Eric; Deng, Zhi; Desch, Klaus; Dieguez, Angel; Diener, Ralf; Dima, Mihai-Octavian; Dissertori, Gunther; Dixit, Madhu S.; Dolezal, Zdenek; Dolgoshein, Boris A.; Dollan, Ralph; Dorokhov, Andrei; Doublet, Philippe; Doyle, Tony; Doziere, Guy; Dragicevic, Marko; Drasal, Zbynek; Drugakov, Vladimir; Duarte Campderros, Jordi; Dulucq, Frederic; Dumitru, Laurentiu Alexandru; Dzahini, Daniel; Eberl, Helmut; Eckerlin, Guenter; Ehrenfeld, Wolfgang; Eigen, Gerald; Eklund, Lars; Elsen, Eckhard; Elsener, Konrad; Emeliantchik, Igor; Engels, Jan; Evrard, Christophe; Fabbri, Riccardo; Faber, Gerard; Faucci Giannelli, Michele; Faus-Golfe, Angeles; Feege, Nils; Feng, Cunfeng; Ferencei, Jozef; Fernandez Garcia, Marcos; Filthaut, Frank; Fleck, Ivor; Fleischer, Manfred; Fleta, Celeste; Fleury, Julien L.; Fontaine, Jean-Charles; Foster, Brian; Fourches, Nicolas; Fouz, Mary-Cruz; Frank, Sebastian; Frey, Ariane; Frotin, Mickael; Fujii, Hirofumi; Fujii, Keisuke; Fujimoto, Junpei; Fujita, Yowichi; Fusayasu, Takahiro; Fuster, Juan; Gaddi, Andrea; Gaede, Frank; Galkin, Alexei; Galkin, Valery; Gallas, Abraham; Gallin-Martel, Laurent; Gamba, Diego; Gao, Yuanning; Garrido Beltran, Lluis; Garutti, Erika; Gastaldi, Franck; Gaur, Bakul; Gay, Pascal; Gellrich, Andreas; Genat, Jean-Francois; Gentile, Simonetta; Gerwig, Hubert; Gibbons, Lawrence; Ginina, Elena; Giraud, Julien; Giraudo, Giuseppe; Gladilin, Leonid; Goldstein, Joel; Gonzalez Sanchez, Francisco Javier; Gournaris, Filimon; Greenshaw, Tim; Greenwood, Z.D.; Grefe, Christian; Gregor, Ingrid-Maria; Grenier, Gerald Jean; Gris, Philippe; Grondin, Denis; Grunewald, Martin; Grzelak, Grzegorz; Gurtu, Atul; Haas, Tobias; Haensel, Stephan; Hajdu, Csaba; Hallermann, Lea; Han, Liang; Hansen, Peter H.; Hara, Takanori; Harder, Kristian; Hartin, Anthony; Haruyama, Tomiyoshi; Harz, Martin; Hasegawa, Yoji; Hauschild, Michael; He, Qing; Hedberg, Vincent; Hedin, David; Heinze, Isa; Helebrant, Christian; Henschel, Hans; Hensel, Carsten; Hertenberger, Ralf; Herve, Alain; Higuchi, Takeo; Himmi, Abdelkader; Hironori, Kazurayama; Hlucha, Hana; Hommels, Bart; Horii, Yasuyuki; Horvath, Dezso; Hostachy, Jean-Yves; Hou, Wei-Shu; Hu-Guo, Christine; Huang, Xingtao; Huppert, Jean Francois; Ide, Yasuhiro; Idzik, Marek; Iglesias Escudero, Carmen; Ignatenko, Alexandr; Igonkina, Olga; Ikeda, Hirokazu; Ikematsu, Katsumasa; Ikemoto, Yukiko; Ikuno, Toshinori; Imbault, Didier; Imhof, Andreas; Imhoff, Marc; Ingbir, Ronen; Inoue, Eiji

    2010-01-01

    The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which st...

  3. Search for pair-produced long-lived neutral particles decaying to jets in the ATLAS hadronic calorimeter in pp collisions at ?s = 8 TeV

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector at the Large Hadron Collider at CERN is used to search for the decay of a scalar boson to a pair of long-lived particles, neutral under the Standard Model gauge group, in 20.3 fb[superscript ?1] of data ...

  4. Search for Diphoton Events with Large Missing Transverse Energy in 6.3 fb-1 of ppbar Collisions using the D0 Detector at the Fermilab Tevatron Collider

    SciTech Connect (OSTI)

    Cooke, Mark Stephen; /Columbia U.

    2010-09-01

    A search for diphoton events with large missing transverse energy produced in p{bar p} collisions at {radical}s = 1.96 TeV is presented. The data were collected with the D0 detector at the Fermilab Tevatron Collider between 2002 and 2010, and correspond to 6.3 fb{sup -1} of integrated luminosity. The observed missing transverse energy distribution is well described by the Standard Model prediction, and 95% C.L. limits are derived on two realizations of theories beyond the Standard Model. In a gauge mediated supersymmetry breaking scenario, the breaking scale {Lambda} is excluded for {Lambda} < 124 TeV. In a universal extra dimension model including gravitational decays, the compactification radius R{sub c} is excluded for R{sub c}{sup -1} < 477 GeV.

  5. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01

    version of the project (CBA) based on magnets wound fromand the early phase of the CBA. Constructed in two stages asdipoles and the cold iron CBA geometry. Sadly, the next

  6. Superconducting Magnet Technology for Future Hadron Colliders

    E-Print Network [OSTI]

    Scanlan, R.M.

    2011-01-01

    Trans. on Applied Superconductivity, 5 (1995), J.R. Millersummer study on superconductingdevices and acceleratorsGeneral. Advanced Superconductors (IGC). Waterbury.

  7. Mass, Spin, and Physics Beyond the Standard Model at Colliders

    E-Print Network [OSTI]

    Klemm, William Lathrop

    2011-01-01

    E. Skillman, “New BBN limits on physics beyond the standardH. Simmons, “Multi - jet physics at hadron colliders,” Nucl.Group], “Review of particle physics,” Phys. Lett. B [108] J.

  8. The International Linear Collider

    E-Print Network [OSTI]

    Marco Battaglia

    2007-05-28

    The International Linear Collider (ILC) is the next large scale project in accelerator particle physics. Colliding electrons with positrons at energies from 0.3 TeV up to about 1 TeV, the ILC is expected to provide the accuracy needed to complement the LHC data and extend the sensitivity to new phenomena at the high energy frontier and answer some of the fundamental questions in particle physics and in its relation to Cosmology. This paper reviews some highlights of the ILC physics program and some of the major challenges for the accelerator and detector design.

  9. Muon Collider

    SciTech Connect (OSTI)

    Palmer, R.

    2009-10-19

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

  10. EIS-0138: Superconducting Super Collider

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this EIS to analyze the potential environmental impacts of constructing the Superconducting Super Collider, a large proton accelerator, at each of seven alternative locations.

  11. ERL BASED ELECTRON-ION COLLIDER ERHIC.

    SciTech Connect (OSTI)

    LITVINENKO,V.N.; BEN-ZVI,I.; ANDERSON,D.; ET AL.

    2005-05-16

    In this paper we describe eRHIC design based on the RHIC hadron rings and 10-to-20 GeV energy recovery electron linac. RHIC requires a very large tunability range for c.m. energies while maintaining very high luminosity up to 10{sup 34} cm{sup -2} s{sup -1} per nucleon. The designs of this future polarized electron-hadron collider, eRHIC, based on a high current super-conducting energy-recovery linac (ERL) with energy of electrons up to 20 GeV, have a number of specific requirements on the ERL optics. Two of the most attractive features of this scheme are full spin transparency of the ERL at all operational energies and the capability to support up to four interaction points. We present two main layouts of the eRHIC, the expected beam and luminosity parameter, and discuss the potential limitation of its performance. Two of the most attractive features of this scheme are full spin transparency of the ERL at all operational energies and the capability to support up to four interaction points. We present two main layouts of the eRHIC, the expected beam and luminosity parameter, and discuss the potential limitation of its performance.

  12. Search for Heavy Resonances Decaying to Taus in 7 TeV Proton-Proton Collisions at the Large Hadron Collider 

    E-Print Network [OSTI]

    Gurrola, Alfredo

    2011-10-21

    pb^-1 of proton-proton collisions at sqrt(s) = 7 TeV collected with the CMS detector at the CERN LHC. The number of observed events in the data is in good agreement with the predictions for SM background processes. In the context of the Sequential SM...

  13. Search for Diphoton Events with Large Missing Transverse Energy in 7 TeV Proton-Proton Collisions with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for diphoton events with large missing transverse energy is presented. The data were collected with the ATLAS detector in proton-proton collisions at ?s=7??[square root of s=7] TeV at the CERN Large Hadron Collider ...

  14. Jets in Particle Colliders Andrew Wong!

    E-Print Network [OSTI]

    Budker, Dmitry

    Jets in Particle Colliders Andrew Wong! #12;Topics · What are jets? · How are they produced? · What do we use to study jets? #12;What are jets? · Bunch of different jets #12;Pretty picture! #12;What's in a jet? · Hadrons ­ Kaons, Pions, Protons, Neutrons · Leptons ­ Mainly electrons and muons · These have

  15. Dark matter and Higgs boson collider implications of fermions in an abelian-gauged hidden sector

    E-Print Network [OSTI]

    Shrihari Gopalakrishna; Seung J. Lee; James D. Wells

    2009-04-13

    We add fermions to an abelian-gauged hidden sector. We show that the lightest can be the dark matter with the right thermal relic abundance, and discovery is within reach of upcoming dark matter detectors. We also show that these fermions change Higgs boson phenomenology at the Large Hadron Collider (LHC), and in particular could induce a large invisible width to the lightest Higgs boson state. Such an invisibly decaying Higgs boson can be discovered with good significance in the vector boson fusion channel at the LHC.

  16. Physics validation studies for muon collider detector background simulations

    SciTech Connect (OSTI)

    Morris, Aaron Owen; /Northern Illinois U.

    2011-07-01

    Within the broad discipline of physics, the study of the fundamental forces of nature and the most basic constituents of the universe belongs to the field of particle physics. While frequently referred to as 'high-energy physics,' or by the acronym 'HEP,' particle physics is not driven just by the quest for ever-greater energies in particle accelerators. Rather, particle physics is seen as having three distinct areas of focus: the cosmic, intensity, and energy frontiers. These three frontiers all provide different, but complementary, views of the basic building blocks of the universe. Currently, the energy frontier is the realm of hadron colliders like the Tevatron at Fermi National Accelerator Laboratory (Fermilab) or the Large Hadron Collider (LHC) at CERN. While the LHC is expected to be adequate for explorations up to 14 TeV for the next decade, the long development lead time for modern colliders necessitates research and development efforts in the present for the next generation of colliders. This paper focuses on one such next-generation machine: a muon collider. Specifically, this paper focuses on Monte Carlo simulations of beam-induced backgrounds vis-a-vis detector region contamination. Initial validation studies of a few muon collider physics background processes using G4beamline have been undertaken and results presented. While these investigations have revealed a number of hurdles to getting G4beamline up to the level of more established simulation suites, such as MARS, the close communication between us, as users, and the G4beamline developer, Tom Roberts, has allowed for rapid implementation of user-desired features. The main example of user-desired feature implementation, as it applies to this project, is Bethe-Heitler muon production. Regarding the neutron interaction issues, we continue to study the specifics of how GEANT4 implements nuclear interactions. The GEANT4 collaboration has been contacted regarding the minor discrepancies in the neutron interaction cross sections for boron. While corrections to the data files themselves are simple to implement and distribute, it is quite possible, however, that coding changes may be required in G4beamline or even in GEANT4 to fully correct nuclear interactions. Regardless, these studies are ongoing and future results will be reflected in updated releases of G4beamline.

  17. Proceedings for TASI 2009 Summer School on "Physics of the Large and the Small": Introduction to the LHC experiments

    E-Print Network [OSTI]

    E. Halkiadakis

    2010-04-30

    These proceedings are a summary of four lectures given at the Theoretical Advanced Study Institute in Elementary Particle Physics (TASI) in 2009. These lectures provide a basic introduction to experimental particle physics and the Large Hadron Collider experiments at CERN, with many general examples from the (still running) Fermilab Tevatron.

  18. Reconstruction of Inert Doublet Scalars at the International Linear Collider

    E-Print Network [OSTI]

    Mayumi Aoki; Shinya Kanemura; Hiroshi Yokoya

    2013-08-19

    We study collider signatures for extra scalar bosons in the inert doublet model at the international linear collider (ILC). The inert doublet model is a simple extension of the standard model by introducing an additional isospin-doublet scalar field which is odd under an unbroken Z_2 symmetry. The model predicts four kinds of Z_2-odd scalar bosons, and the lightest of them becomes stable and a candidate of the dark matter as long as it is electrically neutral. Taking into account the constraints from various theoretical and phenomenological conditions, we perform a simulation study for the distinctive signatures of the extra scalars over the standard-model background contributions at the ILC with the center-of-mass energy of sqrt{s} = 250 GeV and 500 GeV. We further discuss observables for determination of the mass of the scalars. We find that the parameter regions which cannot be detected at the large hadron collider can be probed at the ILC.

  19. Michael Schmitt Physics at a -Collider 20-March-2001 1 Physics at a -Collider

    E-Print Network [OSTI]

    Schmitt, Michael

    . emphasizes diboson over difermion production { in contrast to e + e machines. #15; Pair-production of charged of speci#12;c CP #15; Since photons couple only to electric charge, production of neutral particles to be tied to the data { not unlike hadronic machines. #12; Michael Schmitt Physics at a -Collider 20-March

  20. Future hadron physics at Fermilab

    SciTech Connect (OSTI)

    Appel, Jeffrey A.; /Fermilab

    2005-09-01

    Today, hadron physics research occurs at Fermilab as parts of broader experimental programs. This is very likely to be the case in the future. Thus, much of this presentation focuses on our vision of that future--a future aimed at making Fermilab the host laboratory for the International Linear Collider (ILC). Given the uncertainties associated with the ILC--the level of needed R&D, the ILC costs, and the timing--Fermilab is also preparing for other program choices. I will describe these latter efforts, efforts focused on a Proton Driver to increase the numbers of protons available for experiments. As examples of the hadron physics which will be coming from Fermilab, I summarize three experiments: MIPP/E907 which is running currently, and MINERvA and Drell-Yan/E906 which are scheduled for future running periods. Hadron physics coming from the Tevatron Collider program will be summarized by Arthur Maciel in another talk at Hadron05.

  1. Photoproduction of single inclusive jets at future ep colliders in next-to-leading order QCD

    E-Print Network [OSTI]

    Jäger, B

    2008-01-01

    A next-to-leading order QCD calculation for single-inclusive jet photoproduction in unpolarized and longitudinally polarized lepton-hadron collisions is presented which consistently includes ``direct'' and ``resolved'' photon contributions. The computation is performed within the ``small-cone approximation'' in a largely analytical form. Phenomenological aspects of jet production at future ep colliders such as the CERN-LHeC and the polarized BNL-eRHIC are discussed, placing particular emphasis on the perturbative stability of the predictions and the possibility to constrain the parton content of the photon.

  2. Photoproduction of single inclusive jets at future ep colliders in next-to-leading order QCD

    E-Print Network [OSTI]

    B. Jager

    2008-07-01

    A next-to-leading order QCD calculation for single-inclusive jet photoproduction in unpolarized and longitudinally polarized lepton-hadron collisions is presented which consistently includes ``direct'' and ``resolved'' photon contributions. The computation is performed within the ``small-cone approximation'' in a largely analytical form. Phenomenological aspects of jet production at future ep colliders such as the CERN-LHeC and the polarized BNL-eRHIC are discussed, placing particular emphasis on the perturbative stability of the predictions and the possibility to constrain the parton content of the photon.

  3. Search for microscopic black holes in a like-sign dimuon final state using large track multiplicity with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for microscopic black holes in a like-sign dimuon final state in proton–proton collisions at s?=8??TeV. The data were collected with the ATLAS detector at the Large Hadron Collider in 2012 and correspond ...

  4. The Future of Hadrons: The Nexus of Subatomic Physics

    SciTech Connect (OSTI)

    Quigg, Chris

    2011-09-01

    The author offers brief observations on matters discussed at the XIV International Conference on Hadron Spectroscopy and explore prospects for hadron physics. Quantum chromodynamics (QCD) has been validated as a new law of nature. It is internally consistent up to very high energies, and so could be a complete theory of the strong interactions. Whether QCD is the final answer for the strong interactions is a subject for continuing experimental tests, which are being extended in experimentation at the Large Hadron Collider. Beyond the comparison of perturbative calculations with experiment, it remains critically important to test the confinement hypothesis by searching for free quarks, or for signatures of unconfined color. Sensitive negative searches for quarks continue to be interesting, and the definitive observation of free quarks would be revolutionary. Breakdowns of factorization would compromise the utility of perturbative QCD. Other discoveries that would require small or large revisions to QCD include the observation of new kinds of colored matter beyond quarks and gluons, the discovery that quarks are composite, or evidence that SU(3){sub c} gauge symmetry is the vestige of a larger, spontaneously broken, color symmetry. While probing our underlying theory for weakness or new openings, we have plenty to do to apply QCD to myriad experimental settings, to learn its implications for matter under unusual conditions, and to become more adept at calculating its consequences. New experimental tools provide the means for progress on a very broad front.

  5. Large-x connections of nuclear and high-energy physics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Accardi, Alberto [Hampton U., JLAB

    2013-11-01

    I discuss how global QCD fits of parton distribution functions can make the somewhat separated fields of high-energy particle physics and lower energy hadronic and nuclear physics interact to the benefit of both. I review specific examples of this interplay from recent works of the CTEQ-Jefferson Lab collaboration, including hadron structure at large parton momentum and gauge boson production at colliders. I devote particular attention to quantifying theoretical uncertainties arising in the treatment of large partonic momentum contributions to deep inelastic scattering observables, and to discussing the experimental progress needed to reduce these.

  6. Large-x connections of nuclear and high-energy physics

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Accardi, Alberto

    2013-11-20

    I discuss how global QCD fits of parton distribution functions can make the somewhat separated fields of high-energy particle physics and lower energy hadronic and nuclear physics interact to the benefit of both. I review specific examples of this interplay from recent works of the CTEQ-Jefferson Lab collaboration, including hadron structure at large parton momentum and gauge boson production at colliders. Particular attention is devoted to quantifying theoretical uncertainties arising in the treatment of large partonic momentum contributions to deep inelastic scattering observables, and to discussing the experimental progress needed to reduce these.

  7. Discovering Inelastic Thermal-Relic Dark Matter at Colliders

    E-Print Network [OSTI]

    Izaguirre, Eder; Shuve, Brian

    2015-01-01

    Dark Matter particles with inelastic interactions are ubiquitous in extensions of the Standard Model, yet remain challenging to fully probe with existing strategies. We propose a series of powerful searches at hadron and lepton colliders that are sensitive to inelastic dark matter dynamics. In representative models, we find that the LHC and BaBar could offer strong sensitivity to the thermal-relic dark matter parameter space for dark matter masses between ~100 MeV-100 GeV and fractional mass-splittings above the percent level; future searches at Belle II with a dedicated monophoton trigger could also offer sensitivity to thermal-relic scenarios with masses below a few GeV. Thermal scenarios with either larger masses or splittings are largely ruled out; lower masses remain viable yet may be accessible with other search strategies.

  8. Zentrale Dienste Zentrale Dienste

    E-Print Network [OSTI]

    ¨ontgenlaserprojekt European XFEL, den Large Hadron Collider (LHC) bei Genf sowie den geplanten International Linear Collider

  9. Electroweak symmetry breaking by strong dynamics and the collider phenomenology

    SciTech Connect (OSTI)

    Timothy L. Barklow et al.

    2002-12-23

    We discuss the possible signatures in the electroweak symmetry breaking sector by new strong dynamics at future hadron colliders such as the Tevatron upgrade, the LHC and VLHC, and e{sup +}e{sup -} linear colliders. Examples include a heavy Higgs-like scalar resonance, a heavy Technicolor-like vector resonance and pseudo-Goldstone states, non-resonance signatures via enhanced gauge-boson scattering and fermion compositeness.

  10. Testing Higgs portal dark matter via $Z$ fusion at a linear collider

    E-Print Network [OSTI]

    Shinya Kanemura; Shigeki Matsumoto; Takehiro Nabeshima; Hiroyuki Taniguchi

    2011-02-25

    We investigate the possibility of detecting dark matter at TeV scale linear colliders in the scenario where the dark matter is a massive particle weakly interacting only with the Higgs boson $h$ in the low energy effective theory (the Higgs portal dark matter scenario). The dark matter in this scenario would be difficult to be tested at the CERN Large Hadron Collider when the decay of the Higgs boson into a dark matter pair is not kinematically allowed. We study whether even in such a case the dark matter $D$ can be explored or not via the $Z$ boson fusion process at the International Linear Collider and also at a multi TeV lepton collider. It is found that for the collision energy $\\sqrt{S}>1$ TeV with the integrated luminosity 1 ab$^{-1}$, the signal ($e^{\\pm}e^-\\to e^{\\pm}e^-h^\\ast \\to e^{\\pm}e^-DD$) can be seen after appropriate kinematic cuts. In particular, when the dark matter is a fermion or a vector, which is supposed to be singlet under the standard gauge symmetry, the signal with the mass up to 100 GeV can be tested for the Higgs boson mass to be 120 GeV.

  11. The Potential of the Linac-Ring Type Colliders for Particle and Nuclear Physics

    E-Print Network [OSTI]

    A. K. Ciftci; E. Recepoglu; S. Sultansoy; O. Yavas; M. Yilmaz

    2003-10-02

    Linac-ring type colliders will open new windows for both energy frontier and particle factories. Concerning the first direction, these machines seem to be a sole way to TeV scale in lepton-hadron collisison at constituent level. An essential advantage of the linac-ring type lepton-hadron colliders is the possibility of the construction of gamma-p, gamma-A and FELgamma-A colliders based on them. Today, eRHIC, THERA (TESLA on HERA)and Linac*LHC can be considered as realistic candidates for future lepton-hadron and photon hadron colliders. When it comes to factories, one can reach essentially higher luminosities comparing to standard ring-ring type machines. For example, L=10^34 cm^-2 s^-1 can be achieved for phi and charm-tau factories. In this presentation we briefly discuss the parameters and physics search potential of the linac-ring type machines.

  12. Colliding Crystalline Beams

    E-Print Network [OSTI]

    Wei, J.

    2008-01-01

    6] J. Wei, et ai, Crystalline Beams and Related Issues,LABORATORY Colliding Crystalline Beams Jie Wei and A.M.CBP Note-262 Colliding Crystalline Beams* Jie Wei Brookhaven

  13. Discrimination of New Physics Models with the International Linear Collider

    E-Print Network [OSTI]

    Masaki Asano; Tomoyuki Saito; Taikan Suehara; Keisuke Fujii; R. S. Hundi; Hideo Itoh; Shigeki Matsumoto; Nobuchika Okada; Yosuke Takubo; Hitoshi Yamamoto

    2011-09-28

    The large hadron collider (LHC) is anticipated to provide signals of new physics at the TeV scale, which are likely to involve production of a WIMP dark matter candidate. The international linear collider (ILC) is to sort out these signals and lead us to some viable model of the new physics at the TeV scale. In this article, we discuss how the ILC can discriminate new physics models, taking the following three examples: the inert Higgs model, the supersymmetric model, and the littlest Higgs model with T-parity. These models predict dark matter particles with different spins, 0, 1/2, and 1, respectively, and hence comprise representative scenarios. Specifically, we focus on the pair production process, e+e- -> chi+chi- -> chi0chi0W+W-, where chi0 and chi+- are the WIMP dark matter and a new charged particle predicted in each of these models. We then evaluate how accurately the properties of these new particles can be determined at the ILC and demonstrate that the ILC is capable of identifying the spin of the new charged particle and discriminating these models.

  14. Heavy-ion performance of the LHC and future colliders

    E-Print Network [OSTI]

    AUTHOR|(SzGeCERN)696614; Jowett, John M.

    2015-10-09

    In 2008 the Large Hadron Collider (LHC) and its experiments started operation at the European Centre of Nuclear Research (CERN) in Geneva with the main aim of finding or excluding the Higgs boson. Only four years later, on the 4th of July 2012, the discovery of a Higgs-like particle was proven and first published by the two main experiments ATLAS and CMS. Even though proton–proton collisions are the main operation mode of the LHC, it also acts as an heavy-ion collider. Here, the term “heavy-ion collisions” refers to the collision between fully stripped nuclei. While the major hardware system of the LHC is compatible with heavy-ion operation, the beam dynamics and performance limits of ion beams are quite different from those of protons. Because of the higher mass and charge of the ions, beam dynamic effects like intra-beam scattering and radiation damping are stronger. Also the electromagnetic cross-sections in the collisions are larger, leading to significantly faster intensity decay and thus shorter l...

  15. High-energy high-luminosity electron-ion collider eRHIC

    E-Print Network [OSTI]

    Litvinenko, Vladimir N; Belomestnykh, Sergei; Ben-Zvi, Ilan; Blaskiewicz, Michael M; Calaga, Rama; Chang, Xiangyun; Fedotov, Alexei; Gassner, David; Hammons, Lee; Hahn, Harald; Hao, Yue; He, Ping; Jackson, William; Jain, Animesh; Johnson, Elliott C; Kayran, Dmitry; Kewisch, Jrg; Luo, Yun; Mahler, George; McIntyre, Gary; Meng, Wuzheng; Minty, Michiko; Parker, Brett; Pikin, Alexander; Pozdeyev, Eduard; Ptitsyn, Vadim; Rao, Triveni; Roser, Thomas; Skaritka, John; Sheehy, Brian; Tepikian, Steven; Than, Yatming; Trbojevic, Dejan; Tsentalovich, Evgeni; Tsoupas, Nicholaos; Tuozzolo, Joseph; Wang, Gang; Webb, Stephen; Wu, Qiong; Xu, Wencan; Zelenski, Anatoly

    2011-01-01

    In this paper, we describe a future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference. A new ERL accelerator, which provide 5-30 GeV electron beam, will ensure 10^33 to 10^34 cm^-2 s^-1 level luminosity.

  16. The International Large Detector: Letter of Intent

    E-Print Network [OSTI]

    The ILD Concept Group

    2010-06-17

    The International Large Detector (ILD) is a concept for a detector at the International Linear Collider, ILC. The ILC will collide electrons and positrons at energies of initially 500 GeV, upgradeable to 1 TeV. The ILC has an ambitious physics program, which will extend and complement that of the Large Hadron Collider (LHC). A hallmark of physics at the ILC is precision. The clean initial state and the comparatively benign environment of a lepton collider are ideally suited to high precision measurements. To take full advantage of the physics potential of ILC places great demands on the detector performance. The design of ILD is driven by these requirements. Excellent calorimetry and tracking are combined to obtain the best possible overall event reconstruction, including the capability to reconstruct individual particles within jets for particle ow calorimetry. This requires excellent spatial resolution for all detector systems. A highly granular calorimeter system is combined with a central tracker which stresses redundancy and efficiency. In addition, efficient reconstruction of secondary vertices and excellent momentum resolution for charged particles are essential for an ILC detector. The interaction region of the ILC is designed to host two detectors, which can be moved into the beam position with a push-pull scheme. The mechanical design of ILD and the overall integration of subdetectors takes these operational conditions into account.

  17. Michael Schmitt Physics at a -Collider 15-March-2001 1 Physics at a -Collider

    E-Print Network [OSTI]

    Schmitt, Michael

    machines. #15; Pair-production of charged particles is large and theoretically unambiguous for colorless's { it is possible to prepare initial states of speci#12;c CP #15; Since photons couple only to electric charge hadronic structure. Background estimates will need to be tied to the data, not unlike hadronic machines

  18. Beam-beam Effects of 'Gear-changing' in Ring-Ring Colliders

    E-Print Network [OSTI]

    Hao, Yue; Ptitsyn, Vadim

    2013-01-01

    In ring-ring colliders, the collision frequency determines the bunch structures, e.g. the time between the bunches in both rings should be identical. Because of relatively low relativistic speed of the hadron beam in sub-TeV hadron-hadron- and electron-ions-colliders, scanning the hadron beam's energy would require either a change in the circumference of one of the rings, or a switching of the bunch (harmonic) number in a ring. The later would cause so-called 'gear-changing', i.e. the change of the colliding bunches turn by turn. In this article, we study the difficulties in beam dynamics in this 'gear-changing' scheme.

  19. Photon-Photon Colliders

    E-Print Network [OSTI]

    Sessler, Andrew M.

    2008-01-01

    diverse pairs of particles are produced. In photon-photon colliders. the intensity of the light is so strongunpolarized electrons or photons and fully polarized photons

  20. Single electron yields from semileptonic charm and bottom hadron decays in Au$+$Au collisions at $\\sqrt{s_{NN}}=200$ GeV

    E-Print Network [OSTI]

    A. Adare; C. Aidala; N. N. Ajitanand; Y. Akiba; R. Akimoto; J. Alexander; M. Alfred; K. Aoki; N. Apadula; Y. Aramaki; H. Asano; E. C. Aschenauer; E. T. Atomssa; T. C. Awes; B. Azmoun; V. Babintsev; M. Bai; N. S. Bandara; B. Bannier; K. N. Barish; B. Bassalleck; S. Bathe; V. Baublis; S. Baumgart; A. Bazilevsky; M. Beaumier; S. Beckman; R. Belmont; A. Berdnikov; Y. Berdnikov; D. Black; D. S. Blau; J. S. Bok; K. Boyle; M. L. Brooks; J. Bryslawskyj; H. Buesching; V. Bumazhnov; S. Butsyk; S. Campbell; C. -H. Chen; C. Y. Chi; M. Chiu; I. J. Choi; J. B. Choi; S. Choi; R. K. Choudhury; P. Christiansen; T. Chujo; O. Chvala; V. Cianciolo; Z. Citron; B. A. Cole; M. Connors; N. Cronin; N. Crossette; M. Csanád; T. Csörg?; S. Dairaku; D. Danley; A. Datta; M. S. Daugherity; G. David; K. DeBlasio; K. Dehmelt; A. Denisov; A. Deshpande; E. J. Desmond; O. Dietzsch; L. Ding; A. Dion; P. B. Diss; J. H. Do; M. Donadelli; L. D'Orazio; O. Drapier; A. Drees; K. A. Drees; J. M. Durham; A. Durum; S. Edwards; Y. V. Efremenko; T. Engelmore; A. Enokizono; S. Esumi; K. O. Eyser; B. Fadem; N. Feege; D. E. Fields; M. Finger; M. Finger; \\, Jr.; F. Fleuret; S. L. Fokin; J. E. Frantz; A. Franz; A. D. Frawley; Y. Fukao; T. Fusayasu; K. Gainey; C. Gal; P. Gallus; P. Garg; A. Garishvili; I. Garishvili; H. Ge; F. Giordano; A. Glenn; X. Gong; M. Gonin; Y. Goto; R. Granier de Cassagnac; N. Grau; S. V. Greene; M. Grosse Perdekamp; Y. Gu; T. Gunji; T. Hachiya; J. S. Haggerty; K. I. Hahn; H. Hamagaki; H. F. Hamilton; S. Y. Han; J. Hanks; S. Hasegawa; T. O. S. Haseler; K. Hashimoto; R. Hayano; S. Hayashi; X. He; T. K. Hemmick; T. Hester; J. C. Hill; R. S. Hollis; K. Homma; B. Hong; T. Horaguchi; T. Hoshino; N. Hotvedt; J. Huang; S. Huang; T. Ichihara; H. Iinuma; Y. Ikeda; K. Imai; Y. Imazu; J. Imrek; M. Inaba; A. Iordanova; D. Isenhower; A. Isinhue; D. Ivanishchev; B. V. Jacak; M. Javani; M. Jezghani; J. Jia; X. Jiang; B. M. Johnson; K. S. Joo; D. Jouan; D. S. Jumper; J. Kamin; S. Kanda; B. H. Kang; J. H. Kang; J. S. Kang; J. Kapustinsky; K. Karatsu; D. Kawall; A. V. Kazantsev; T. Kempel; J. A. Key; V. Khachatryan; P. K. Khandai; A. Khanzadeev; K. M. Kijima; B. I. Kim; C. Kim; D. J. Kim; E. -J. Kim; G. W. Kim; M. Kim; Y. -J. Kim; Y. K. Kim; B. Kimelman; E. Kinney; E. Kistenev; R. Kitamura; J. Klatsky; D. Kleinjan; P. Kline; T. Koblesky; B. Komkov; J. Koster; D. Kotchetkov; D. Kotov; F. Krizek; K. Kurita; M. Kurosawa; Y. Kwon; G. S. Kyle; R. Lacey; Y. S. Lai; J. G. Lajoie; A. Lebedev; D. M. Lee; J. Lee; K. B. Lee; K. S. Lee; S Lee; S. H. Lee; S. R. Lee; M. J. Leitch; M. A. L. Leite; M. Leitgab; B. Lewis; X. Li; S. H. Lim; L. A. Linden Levy; M. X. Liu; D. Lynch; C. F. Maguire; Y. I. Makdisi; M. Makek; A. Manion; V. I. Manko; E. Mannel; T. Maruyama; M. McCumber; P. L. McGaughey; D. McGlinchey; C. McKinney; A. Meles; M. Mendoza; B. Meredith; Y. Miake; T. Mibe; J. Midori; A. C. Mignerey; A. Milov; D. K. Mishra; J. T. Mitchell; S. Miyasaka; S. Mizuno; A. K. Mohanty; S. Mohapatra; P. Montuenga; H. J. Moon; T. Moon; D. P. Morrison; M. Moskowitz; T. V. Moukhanova; T. Murakami; J. Murata; A. Mwai; T. Nagae; S. Nagamiya; K. Nagashima; J. L. Nagle; M. I. Nagy; I. Nakagawa; H. Nakagomi; Y. Nakamiya; K. R. Nakamura; T. Nakamura; K. Nakano; C. Nattrass; P. K. Netrakanti; M. Nihashi; T. Niida; S. Nishimura; R. Nouicer; T. Novak; N. Novitzky; A. Nukariya; A. S. Nyanin; H. Obayashi; E. O'Brien; C. A. Ogilvie; K. Okada; J. D. Orjuela Koop; J. D. Osborn; A. Oskarsson; K. Ozawa; R. Pak; V. Pantuev; V. Papavassiliou; I. H. Park; J. S. Park; S. Park; S. K. Park; S. F. Pate; L. Patel; M. Patel; H. Pei; J. -C. Peng; D. V. Perepelitsa; G. D. N. Perera; D. Yu. Peressounko; J. Perry; R. Petti; C. Pinkenburg; R. Pinson; R. P. Pisani; M. L. Purschke; H. Qu; J. Rak; B. J. Ramson; I. Ravinovich; K. F. Read; D. Reynolds; V. Riabov; Y. Riabov; E. Richardson; T. Rinn; N. Riveli; D. Roach; G. Roche; S. D. Rolnick; M. Rosati; Z. Rowan; J. G. Rubin; M. S. Ryu; B. Sahlmueller; N. Saito; T. Sakaguchi; H. Sako; V. Samsonov; M. Sarsour; S. Sato; S. Sawada; B. Schaefer; B. K. Schmoll; K. Sedgwick; R. Seidl; A. Sen; R. Seto; P. Sett; A. Sexton; D. Sharma; I. Shein; T. -A. Shibata; K. Shigaki; M. Shimomura; K. Shoji; P. Shukla; A. Sickles; C. L. Silva; D. Silvermyr; K. S. Sim; B. K. Singh; C. P. Singh; V. Singh; M. Skolnik; M. Slune?ka; M. Snowball; S. Solano; R. A. Soltz; W. E. Sondheim; S. P. Sorensen; I. V. Sourikova; P. W. Stankus; P. Steinberg; E. Stenlund; M. Stepanov; A. Ster; S. P. Stoll; T. Sugitate; A. Sukhanov; T. Sumita; J. Sun; J. Sziklai; E. M. Takagui; A. Takahara; A. Taketani; Y. Tanaka; S. Taneja; K. Tanida; M. J. Tannenbaum; S. Tarafdar; A. Taranenko; E. Tennant; R. Tieulent; A. Timilsina; T. Todoroki; M. Tomášek; H. Torii; C. L. Towell; R. Towell; R. S. Towell; I. Tserruya; Y. Tsuchimoto; C. Vale; H. W. van Hecke; M. Vargyas; E. Vazquez-Zambrano; A. Veicht

    2015-09-15

    The PHENIX Collaboration at the Relativistic Heavy Ion Collider has measured open heavy-flavor production in minimum bias Au$+$Au collisions at $\\sqrt{s_{_{NN}}}=200$ GeV via the yields of electrons from semileptonic decays of charm and bottom hadrons. Previous heavy-flavor electron measurements indicated substantial modification in the momentum distribution of the parent heavy quarks due to the quark-gluon plasma created in these collisions. For the first time, using the PHENIX silicon vertex detector to measure precision displaced tracking, the relative contributions from charm and bottom hadrons to these electrons as a function of transverse momentum are measured in Au$+$Au collisions. We compare the fraction of electrons from bottom hadrons to previously published results extracted from electron-hadron correlations in $p$$+$$p$ collisions at $\\sqrt{s_{_{NN}}}=200$ GeV and find the fractions to be similar within the large uncertainties on both measurements for $p_T>4$ GeV/$c$. We use the bottom electron fractions in Au$+$Au and $p$$+$$p$ along with the previously measured heavy flavor electron $R_{AA}$ to calculate the $R_{AA}$ for electrons from charm and bottom hadron decays separately. We find that electrons from bottom hadron decays are less suppressed than those from charm for the region $3

  1. Hidden-Sector Higgs Bosons at High-Energy Electron-Positron Colliders

    E-Print Network [OSTI]

    Jack H. Collins; James D. Wells

    2012-09-30

    The possibility of a scalar messenger that can couple the Standard Model (SM) to a hidden sector has been discussed in a variety of contexts in the literature in recent years. We consider the case that a new scalar singlet charged under an exotic spontaneously broken Abelian gauge symmetry mixes weakly with the SM Higgs resulting in two scalar mass states, one of which has heavily suppressed couplings to the SM particles. Previous phenomenological studies have focussed on potential signatures for such a model at the Large Hadron Collider (LHC). However, there are interesting regions of the parameter space in which the heavier Higgs state would be out of reach for LHC searches if its mass is greater than 1 TeV. We therefore investigate the discovery potential for such a particle at a 3 TeV electron-positron collider, which is motivated by the recent developments of the Compact Linear Collider (CLIC). We find that such an experiment could substantially extend our discovery reach for a heavy, weakly coupled Higgs boson, and we discuss three possible search channels.

  2. Effects of Shower Partons on Soft and Semihard hadrons Produced in Pb-Pb Collisions at 2.76 TeV

    E-Print Network [OSTI]

    Lilin Zhu; Rudolph C. Hwa

    2014-11-05

    The production of all identified hadrons at the CERN Large Hadron Collider (LHC) is studied with emphasis on the $p_T$ distributions up to 20 GeV/c in central collisions. In the framework of the recombination model we find that the shower partons (due to the fragmentation of semihard partons) play an important role in the formation of hadrons in the low- and intermediate-$p_T$ regions. Parameters that control the energy loss of minijets are determined by fitting the upper half of the $p_T$ range of the pion distribution. The resultant soft shower partons are then found to dominate over the thermal partons in the non-strange sector, but not in the strange sector. Since the data on the $p_T$ spectra of all observed hadrons are well reproduced, there is no way out of the implication that any alternative dynamical model on particle production would be incomplete if it does not consider the effects of minijets even at very low $p_T$. Hydrodynamics that relies on rapid equilibration without accounting for the delayed thermalization effects of the hard and semihard partons copiously produced at LHC is an example of such models. The difference between the densities of shower partons produced at LHC and at BNL Relativistic Heavy-Ion Collider (RHIC) is quantified and discussed.

  3. Search for metastable heavy charged particles with large ionisation energy loss in pp collisions at ${\\sqrt{s} = 8}$ s = 8 TeV using the ATLAS experiment

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.

    2015-09-03

    Many extensions of the Standard Model predict the existence of charged heavy long-lived particles, such as R-hadrons or charginos. These particles, if produced at the Large Hadron Collider, should be moving non-relativistically and are therefore identifiable through the measurement of an anomalously large specific energy loss in the ATLAS pixel detector. Measuring heavy long-lived particles through their track parameters in the vicinity of the interaction vertex provides sensitivity to metastable particles with lifetimes from 0.6 ns to 30 ns. A search for such particles with the ATLAS detector at the Large Hadron Collider is presented, based on a data samplemore »corresponding to an integrated luminosity of \\(18.4\\) fb\\(^{-1}\\) of pp collisions at \\(\\sqrt{s} = 8\\) TeV. No significant deviation from the Standard Model background expectation is observed, and lifetime-dependent upper limits on R-hadrons and chargino production are set. Gluino R-hadrons with 10 ns lifetime and masses up to 1185 GeV are excluded at 95 \\(\\%\\) confidence level, and so are charginos with 15 ns lifetime and masses up to 482 GeV.« less

  4. Energy flow in a hadronic cascade: Application to hadron calorimetry

    E-Print Network [OSTI]

    Groom, Donald E.

    2006-01-01

    Detector at the International Linear Collider,” http://connection with International Linear Collider (ILC) detectorfor the International Linear Collider[59]. Improved

  5. Soft hadron production in pp interactions up to ISR energies

    E-Print Network [OSTI]

    H. Mueller

    2000-11-28

    Soft hadron production is described as a two-step process, where the interaction of the partonic constituents of the colliding hadrons leads to the production of intermediate subsystems (fireballs), which decay subsequently into hadrons. The weights of the various final states are derived from the corresponding phase-space factors modified by empirical transition elements. The results compare well with data at energies between particle production thresholds and ISR energies. Special emphasis is put on correlation data, which offer the opportunity to shed some light on the question whether particle production proceeds via fireballs or strings.

  6. Universal QGP Hadronization Conditions at RHIC and LHC

    E-Print Network [OSTI]

    Johann Rafelski; Michal Petran

    2014-06-07

    We address the principles governing QGP hadronization and particle production in relativistic heavy-ion collisions. We argue that chemical non-equilibrium is required and show that once this condition is assumed a very good description of hadron production in collider RHIC and at LHC heavy ion experiments follows. We present results of our analysis as a function of centrality. Comparing most extreme experimental conditions we show that only the reaction volume and degree of strangeness phase space saturation change. We determine the universal QGP fireball hadronization conditions.

  7. Science Requirements and Conceptual Design for a Polarized Medium Energy Electron-Ion Collider at Jlab

    SciTech Connect (OSTI)

    Abeyratne, S; Ahmed, S; Barber, D; Bisognano, J; Bogacz, A; Castilla, A; Chevtsov, P; Corneliussen, S; Deconinck, W; Degtiarenko, P; Delayen, J; Derbenev, Ya; DeSilva, S; Douglas, D; Dudnikov, V; Ent, R; Erdelyi, B; Evtushenko, P; Fujii, Yu; Filatov, Yury; Gaskell, D; Geng, R; Guzey, V; Horn, T; Hutton, A; Hyde, C; Johnson, R; Kim, Y; Klein, F; Kondratenko, A; Kondratenko, M; Krafft, G; Li, R; Lin, F; Manikonda, S; Marhauser, F; McKeown, R; Morozov, V; Dadel-Turonski, P; Nissen, E; Ostroumov, P; Pivi, M; Pilat, F; Poelker, M; Prokudin, A; Rimmer, R; Satogata, T; Sayed, H; Spata, M; Sullivan, M; Tennant, C; Terzic, B; Tiefenback, M; Wang, M; Wang, S; Weiss, C; Yunn, B

    2012-08-01

    Researchers have envisioned an electron-ion collider with ion species up to heavy ions, high polarization of electrons and light ions, and a well-matched center-of-mass energy range as an ideal gluon microscope to explore new frontiers of nuclear science. In its most recent Long Range Plan, the Nuclear Science Advisory Committee (NSAC) of the US Department of Energy and the National Science Foundation endorsed such a collider in the form of a 'half-recommendation.' As a response to this science need, Jefferson Lab and its user community have been engaged in feasibility studies of a medium energy polarized electron-ion collider (MEIC), cost-effectively utilizing Jefferson Lab's already existing Continuous Electron Beam Accelerator Facility (CEBAF). In close collaboration, this community of nuclear physicists and accelerator scientists has rigorously explored the science case and design concept for this envisioned grand instrument of science. An electron-ion collider embodies the vision of reaching the next frontier in Quantum Chromodynamics - understanding the behavior of hadrons as complex bound states of quarks and gluons. Whereas the 12 GeV Upgrade of CEBAF will map the valence-quark components of the nucleon and nuclear wave functions in detail, an electron-ion collider will determine the largely unknown role sea quarks play and for the first time study the glue that binds all atomic nuclei. The MEIC will allow nuclear scientists to map the spin and spatial structure of quarks and gluons in nucleons, to discover the collective effects of gluons in nuclei, and to understand the emergence of hadrons from quarks and gluons. The proposed electron-ion collider at Jefferson Lab will collide a highly polarized electron beam originating from the CEBAF recirculating superconducting radiofrequency (SRF) linear accelerator (linac) with highly polarized light-ion beams or unpolarized light- to heavy-ion beams from a new ion accelerator and storage complex. Since the very beginning, the design studies at Jefferson Lab have focused on achieving high collider performance, particularly ultrahigh luminosities up to 10{sup 34} cm{sup -2}s{sup -1} per detector with large acceptance, while maintaining high polarization for both the electron and light-ion beams. These are the two key performance requirements of a future electron-ion collider facility as articulated by the NSAC Long Range Plan. In MEIC, a new ion complex is designed specifically to deliver ion beams that match the high bunch repetition and highly polarized electron beam from CEBAF. During the last two years, both development of the science case and optimization of the machine design point toward a medium-energy electron-ion collider as the topmost goal for Jefferson Lab. The MEIC, with relatively compact collider rings, can deliver a luminosity above 10{sup 34} cm{sup -2}s{sup -1} at a center-of-mass energy up to 65 GeV. It offers an electron energy up to 11 GeV, a proton energy up to 100 GeV, and corresponding energies per nucleon for heavy ions with the same magnetic rigidity. This design choice balances the scope of the science program, collider capabilities, accelerator technology innovation, and total project cost. An energy upgrade could be implemented in the future by adding two large collider rings housed in another large tunnel to push the center-of-mass energy up to or exceeding 140 GeV. After careful consideration of an alternative electron energy recovery linac on ion storage ring approach, a ring-ring collider scenario at high bunch repetition frequency was found to offer fully competitive performance while eliminating the uncertainties of challenging R&D on ampere-class polarized electron sources and many-pass energy-recovery linacs (ERLs). The essential new elements of an MEIC facility at Jefferson Lab are an electron storage ring and an entirely new, modern ion acceleration and storage complex. For the high-current electron collider ring, the upgraded 12 GeV CEBAF SRF linac will serve as a full-energy injector, and, if needed, provide top

  8. Linear Collider Physics Resource Book Snowmass 2001

    SciTech Connect (OSTI)

    Ronan (Editor), 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 built in a few years, it would make sense to wait for the results of each accelerator before planning the next one. Thus, we would wait for the results from the Tevatron before planning the LHC experiments, and wait for the LHC before planning any later stage. In reality accelerators require a long time to construct, and they require such specialized resources and human talent that delay can cripple what would be promising opportunities. In any event, we believe that the case for the linear collider is so compelling and robust that we can justify this facility on the basis of our current knowledge, even before the Tevatron and LHC experiments are done. The physics prospects for the linear collider have been studied intensively for more than a decade, and arguments for the importance of its experimental program have been developed from many different points of view. This book provides an introduction and a guide to this literature. We hope that it will allow physicists new to the consideration of linear collider physics to start from their own personal perspectives and develop their own assessments of the opportunities afforded by a linear collider.

  9. Large

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverseIMPACTThousand CubicResourcelogo and mastheadLakeLanguage of a fly provesLarge

  10. The International Linear Collider

    E-Print Network [OSTI]

    Jim Brau; Paul Grannis; Mike Harrison; Michael Peskin; Marc Ross; Harry Weerts

    2013-04-09

    We present a brief summary of the International Linear Collider as documented in the 2013 Technical Design Report. The Technical Design Report has detailed descriptions of the accelerator baseline design for a 500 GeV e+e- linear collider, the R&D program that has demonstrated its feasibility, the physics goals and expected sensitivities, and the description of the ILD and SiD detectors and their capabilities.

  11. Hadron-hadron and hadron-nuclei collisions at high energies

    E-Print Network [OSTI]

    G. Giacomelli; R. Giacomelli

    2000-11-15

    A brief review is made of the present situation of hadron-hadron and hadron-nuclei total elastic and inelastic cross sections at high energies

  12. Updated measurements of hadronic B decays at CDF

    SciTech Connect (OSTI)

    Morello, Michael J.

    2012-01-01

    The CDF experiment at the Tevatron p{bar p} collider established that extensive and detailed exploration of the b-quark dynamics is possible in hadron collisions, with results competitive and supplementary to those from e{sup +}e{sup -} colliders. This provides a rich, and highly rewarding program that has currently reached full maturity. In the following I report some recent results on hadronic decays: the evidence for the charmless annihilation decay mode B{sub s}{sup 0} {yields} {pi}{sup +}{pi}{sup -}, and the first reconstruction in hadron collisions of the suppressed decays B{sup -} {yields} D({yields} K{sup +}{pi}{sup 0})K{sup -} and B{sup -} {yields} D({yields} K{sup +} {pi}{sup -}){pi}{sup -}.

  13. QCD effects in Higgs boson production at hadron colliders

    E-Print Network [OSTI]

    M. Grazzini

    2010-01-21

    We present updated predictions for Higgs boson production at the Tevatron and the LHC and we review their corresponding uncertainties. We report on a study of the impact of QCD radiative corrections on the Higgs boson search at the Tevatron.

  14. QCD Corrections to Scalar Diquark Production at Hadron Colliders

    E-Print Network [OSTI]

    Tao Han; Ian Lewis; Thomas McElmurry

    2010-02-15

    We calculate the next-to-leading order QCD corrections to quark-quark annihilation to a scalar resonant state ("diquark") in a color representation of antitriplet or sextet at the Tevatron and LHC energies. At the LHC, we find the enhancement (K-factor) for the antitriplet diquark is typically about 1.31--1.35, and for the sextet diquark is about 1.22--1.32 for initial-state valence quarks. The full transverse-momentum spectrum for the diquarks is also calculated at the LHC by performing the soft gluon resummation to the leading logarithm and all orders in the strong coupling.

  15. Nuclear shadowing and prompt photons at relativistic hadron colliders

    E-Print Network [OSTI]

    C. Brenner Mariotto; V. P. Goncalves

    2008-08-26

    The production of prompt photons at high energies provides a direct probe of the dynamics of the strong interactions. In particular, one expect that it could be used to constrain the behavior of the nuclear gluon distribution in $pA$ and $AA$ collisions. In this letter we investigate the influence of nuclear effects in the production of prompt photons and estimate the transverse momentum dependence of the nuclear ratios $R_{pA} = {\\frac{d\\sigma (pA)}{dy d^2 p_T}} / A {\\frac{d\\sigma (pp)}{dy d^2 p_T}}$ and $R_{AA} = {\\frac{d\\sigma (AA)}{dy d^2 p_T}} / A^2 {\\frac{d\\sigma (pp)}{dy d^2 p_T}}$ at RHIC and LHC energies. We demonstrate that the study of these observables can be useful to determine the magnitude of the shadowing and antishadowing effects in the nuclear gluon distribution.

  16. Dark matter signals in dilepton production at hadron colliders (Journal

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing BacteriaConnect Collidertransfer (Journal Article)Journal Article:

  17. The Dark Penguin Shines Light at Colliders

    E-Print Network [OSTI]

    Primulando, Reinard; Tsai, Yuhsin

    2015-01-01

    Collider experiments are one of the most promising ways to constrain Dark Matter (DM) interactions. For several types of DM-Standard Model couplings, a meaningful interpretation of the results requires to go beyond effective field theory, considering simplified models with light mediators. This is especially important in the case of loop-mediated interactions. In this paper we perform the first simplified model study of the magnetic dipole interacting DM, by including the one-loop momentum-dependent form factors that mediate the coupling -- given by the Dark Penguin -- in collider processes. We compute bounds from the monojet, monophoton, and diphoton searches at the $8$ and $14$ TeV LHC, and compare the results to those of direct and indirect detection experiments. Future searches at the $100$ TeV hadron collider and at the ILC are also addressed. We find that the optimal search strategy requires loose cuts on the missing transverse energy, to capture the enhancement of the form factors near the threshold fo...

  18. High energy hadron-hadron collisions

    SciTech Connect (OSTI)

    Chou, T.T.

    1991-12-01

    Results of a study on high energy collision with the geometrical model are summarized in three parts: (1) the elastic hadron-hadron collision, (2) the inelastic hadron-hadron collision, and (3) the e{sup +}e{sup {minus}} annihilation. More recent studies are highlighted below. For elastic scattering, a modified form for the hadronic matter form factor of the proton was proposed which remains to be dipole in form but contains an energy-dependent range parameter. This new expression of the opacity function fits the elastic {bar p}p scattering very well from the ISR to S{bar p}pS energies. Extrapolation of this theory also yielded results in good agreement with the {bar p}p differential cross section measured at the Tevatron. For inelastic hadron-hadron collisions, we have made a systematic investigation of the single-particle momentum spectra in the entire S{bar p}pS energy region. Results are useful for the extrapolation of angular distribution to the higher SSC energies. In e{sup +}e{sup {minus}} annihilation, a detailed analysis of all available experimental multiplicity data from PETRA to LEP energies has been performed. We discovered that the cluster size of emitted hadrons increases steadily with energy and is close to 2 as we predicted.

  19. Photon collider at TESLA

    E-Print Network [OSTI]

    Valery Telnov

    2001-03-06

    High energy photon colliders (gamma-gamma, gamma-electron) 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 gamma-gamma luminosity luminosity in the high energy part of spectrum can reach (1/3)L_{e+e-}. Typical cross sections of interesting processes in gamma-gamma collisions are higher than those in e+e- collisions by about one order of magnitude, so the number of events in gamma-gamma 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 diode pumped solid state laser injector which is today technically feasible. This paper briefly reviews the status of a photon collider based at TESLA, its possible parameters and existing problems.

  20. The Muon Collider

    SciTech Connect (OSTI)

    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.

  1. The Muon Collider

    SciTech Connect (OSTI)

    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.

  2. International linear collider reference design report

    E-Print Network [OSTI]

    Aarons, G.

    2008-01-01

    A. Loew, et al. , “International Linear Collider Technologyfor the International Linear Collider”, in preparation [37]for the International Linear Collider,” in PAC05,http://

  3. Probing the Quark Sea and Gluons: the Electron-Ion Collider Projects

    SciTech Connect (OSTI)

    Rolf Ent

    2012-04-01

    EIC is the generic name for the nuclear science-driven Electron-Ion Collider presently considered in the US. Such an EIC would be the world’s first polarized electron-proton collider, and the world’s first e-A collider. Very little remains known about the dynamical basis of the structure of hadrons and nuclei in terms of the fundamental quarks and gluons of Quantum Chromodynamics (QCD). A large community effort to sharpen a compelling nuclear science case for an EIC occurred during a ten-week program taking place at the Institute for Nuclear Theory (INT) in Seattle from September 13 to November 19, 2010. The critical capabilities of a stage-I EIC are a range in center-of-mass energies from 20 to 70 GeV and variable, full polarization of electrons and light ions (the latter both longitudinal and transverse), ion species up to A=200 or so, multiple interaction regions, and a high luminosity of about 10{sup 34} electron-nucleons per cm{sup 2} and per second. The physics program of such a stage-I EIC encompass inclusive measurements (ep/A{yields}e'+X), which require detection of the scattered lepon and/or the full scattered hadronic debris with high precision, semi-inclusive processes (ep/A{yields}e'+h+X), which require detection in coincidence with the scattered lepton of at least one (current or target region) hadron; and exclusive processes (ep/A{yields}e'+N'/A'+{gamma}/m), which require detection of all particles in the reaction. The main science themes of an EIC are to i) map the spin and spatial structure of quarks and gluons in nucleons, ii) discover the collective effects of gluons in atomic nuclei, and (iii) understand the emergence of hadronic matter from color charge. In addition, there are opportunities at an EIC for fundamental symmetry and nucleon structure measurements using the electroweak probe. To truly make headway to image the sea quarks and gluons in nucleons and nuclei, the EIC needs high luminosity over a range of energies as more exclusive scattering probabilities are small, and any integrated detector/interaction region design needs to provide uniform coverage to detect spectator and diffractive products. This is because e-p and even more e-A colliders have a large fraction of their science related to what happens to the nucleon or ion beams. As a result, the philosophy of integration of complex detectors into an extended interaction region faces challenging constraints. Designs feature crossing angles between the protons or heavy ions during collisions with electrons, to remove potential problems for the detector induced by synchrotron radiation. Designs allocate quite some detector space before the final-focus ion quads, at the cost of luminosity, given that uniform detection coverage is a must for deep exclusive and diffractive processes. The integrated EIC detector/interaction region design at JLab focused on establishing full acceptance for such processes over a wide range of proton energies (20-100 GeV) with well achievable interaction region magnets. The detector design at BNL uses the higher ion beam energies to achieve good detection efficiency for instance for protons following a DVCS reaction, for proton beam energies starting from 100 GeV. Following a recommendation of the 2007 US Nuclear Science Long-Range Planning effort, the DOE Office of Nuclear Physics (DOE/NP) has allocated accelerator R&D funds to lay the foundation for a polarized EIC. BNL, in association with JLab and DOE/NP, has also established a generic detector R&D program to address the scientific requirements for measurements at a future EIC.

  4. Search for Gluino-Mediated Supersymmetry in Events With Bottom-Quark Jets and Missing Transverse Energy With the Compact Muon Solenoid Detector at the Large Hadron Collider With Proton-Proton Collisions at 8 TeV

    E-Print Network [OSTI]

    Nguyen, Harold

    2013-01-01

    Jets . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67 Photon + Jets Control Sample . . . . . . . . .71 t t ¯ , W +jets, Single Top, and QCD

  5. A Measurement of the Underlying Event Distributions in Proton-Proton Collisions at sqrt(s) = 7 TeV in Events containing Charged Particle Jets using the ATLAS Detector at the Large Hadron Collider

    E-Print Network [OSTI]

    Virzi, Joseph Salvatore

    2012-01-01

    3.5.3 Jet Reconstruction . . . . . . . . . . . . . . . 4Leading Jet . . . . . . . . . . . . . . . 6.6 Discretizationdifferent stages of track reconstruction. Jet reconstruction

  6. Stochastic Cooling in Muon Colliders

    E-Print Network [OSTI]

    Barletta, W.A.

    2008-01-01

    Research Division Stochastic Cooling in Muon Colliders W.A.AC03-76SFOOO98. STOCHASTIC COOLING IN MUON COLLIDERS Williamcan consider the stochastic cooling option as more than a

  7. CERN-PH-TH/2007-206 SACLAY-T07/142

    E-Print Network [OSTI]

    Durrer, Ruth

    to the Large Hadron Collider and the future International Linear Collider. Many types of new physics predict

  8. First measurement of ADS parameters using $B^- \\to D^0K^-$ decays in hadron collisions

    SciTech Connect (OSTI)

    Garosi, Paola; /Siena U. /INFN, Pisa

    2011-06-01

    Measurements of branching fractions and CP-asymmetries of B{sup -} {yields} D{sup 0}K{sup -} modes allow a theoretically-clean extraction of the CKM angle {gamma}. The method proposed by Atwood, Dunietz and Soni (ADS) makes use of a decay chain where color and Cabibbo suppression interfere, which produces large CP-violating asymmetries. The CDF experiment reports the first measurement at a hadron collider of branching fractions and CP-asymmetries of suppressed B{sup -} {yields} D{sup 0}h{sup -} signals, where h is {pi} or K. Using 5.0 fb{sup -1} of data we found a combined significance exceeding 5{sigma} and we determined the ADS parameters with accuracy comparable with B-factories.

  9. First measurement of ADS parameters using B- -> D0K- decays in hadron collisions

    E-Print Network [OSTI]

    Paola Garosi; for the CDF Collaboration

    2011-06-22

    Measurements of branching fractions and CP-asymmetries of B^{-} \\rightarrow D^{0}K^{-} modes allow a theoretically-clean extraction of the CKM angle \\gamma. The method proposed by Atwood, Dunietz and Soni (ADS) makes use of a decay chain where color and Cabibbo suppression interfere, which produces large CP-violating asymmetries. The CDF experiment reports the first measurement at a hadron collider of branching fractions and CP-asymmetries of suppressed B^{-} \\rightarrow D^{0}h^{-} signals, where h is \\pi or K. Using 5.0 fb^{-1} of data we found a combined significance exceeding 5\\sigma and we determined the ADS parameters with accuracy comparable with B-factories.

  10. Neutrinos and Collider Physics

    E-Print Network [OSTI]

    Deppisch, Frank F; Pilaftsis, Apostolos

    2015-01-01

    We review the collider phenomenology of neutrino physics and the synergetic aspects at energy, intensity and cosmic frontiers to test the new physics behind the neutrino mass mechanism. In particular, we focus on seesaw models within the minimal setup as well as with extended gauge and/or Higgs sectors, and on supersymmetric neutrino mass models with seesaw mechanism and with $R$-parity violation. In the simplest Type-I seesaw scenario with sterile neutrinos, we summarize and update the current experimental constraints on the sterile neutrino mass and its mixing with the active neutrinos. We also discuss the future experimental prospects of testing the seesaw mechanism at colliders and in related low-energy searches for rare processes, such as lepton flavor violation and neutrinoless double beta decay. The implications of the discovery of lepton number violation at the LHC for leptogenesis are also studied.

  11. Neutrinos and Collider Physics

    E-Print Network [OSTI]

    Frank F. Deppisch; P. S. Bhupal Dev; Apostolos Pilaftsis

    2015-08-04

    We review the collider phenomenology of neutrino physics and the synergetic aspects at energy, intensity and cosmic frontiers to test the new physics behind the neutrino mass mechanism. In particular, we focus on seesaw models within the minimal setup as well as with extended gauge and/or Higgs sectors, and on supersymmetric neutrino mass models with seesaw mechanism and with $R$-parity violation. In the simplest Type-I seesaw scenario with sterile neutrinos, we summarize and update the current experimental constraints on the sterile neutrino mass and its mixing with the active neutrinos. We also discuss the future experimental prospects of testing the seesaw mechanism at colliders and in related low-energy searches for rare processes, such as lepton flavor violation and neutrinoless double beta decay. The implications of the discovery of lepton number violation at the LHC for leptogenesis are also studied.

  12. The International Linear Collider

    E-Print Network [OSTI]

    Karsten Buesser

    2013-06-13

    The International Linear Collider (ILC) is a proposed electron-positron collider for the centre-of-mass energy range of 200 to 500 GeV and with upgrade options towards 1 TeV. The ILC would be the ideal tool to explore with high precision the properties of the new Higgs-like particle that has recently been discovered at the LHC with a mass of around 125 GeV. The ILC accelerator design is based on the mature superconducting technology that has been developed in the TESLA collaboration and that is currently being used for the European XFEL. The exploitation of the huge physics potential of the ILC is a challenge for the design of the ILC detectors.

  13. arXiv:acc-phys/9602001v112Feb1996 MUON COLLIDERS

    E-Print Network [OSTI]

    Wurtele, Jonathan

    , A. Garren3,7 , M. Green3 , S. Kahn1 , H. Kirk1 , Y. Y. Lee1 , F. Mills5 , N. Mokhov5 , G. Morgan1 on upgrades of the FERMILAB machines would also be possible (see second Ref. [4]). Hadron collider energies are limited by their size and technical constraints on bending magnetic fields. At very high energies it would

  14. Nuclear effects on hadron production in d plus Au collisions at root S(NN)=200 GeV revealed by comparison with p plus p data 

    E-Print Network [OSTI]

    Adler, S. S.; Afanasiev, S.; Aidala, C.; Ajitanand, N. N.; Akiba, Y.; Al-Jamel, A.; Alexander, J.; Aoki, K.; Aphecetche, L.; Armendariz, R.; Aronson, S. H.; Averbeck, R.; Awes, T. C.; Babintsev, V.; Baldisseri, A.; Barish, K. N.; Barnes, P. D.; Bassalleck, B.; Bathe, S.; Batsouli, S.; Baublis, V.; Bauer, F.; Bazilevsky, A.; Belikov, S.; Bjorndal, M. T.; Boissevain, J. G.; Borel, H.; Brooks, M. L.; Brown, D. S.; Bruner, N.; Bucher, D.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Burward-Hoy, J. M.; Butsyk, S.; Camard, X.; Chand, P.; Chang, W. C.; Chernichenko, S.; Chi, C. Y.; Chiba, J.; Chiu, M.; Choi, I. J.; Choudhury, R. K.; Chujo, T.; Cianciolo, V.; Cobigo, Y.; Cole, B. A.; Comets, M. P.; Constantin, P.; Csanad, M.; Csorgo, T.; Cussonneau, J. P.; d'Enterria, D.; Das, K.; David, G.; Deak, F.; Delagrange, H.; Denisov, A.; Deshpande, A.; Desmond, E. J.; Devismes, A.; Dietzsch, O.; Drachenberg, J. L.; Drapier, O.; Drees, A.; Durum, A.; Dutta, D.; Dzhordzhadze, V.; Efremenko, Y. V.; En'yo, H.; Espagnon, B.; Esumi, S.; Fields, D. E.; Finck, C.; Fleuret, F.; Fokin, S. L.; Fox, B. D.; Fraenkel, Z.; Frantz, J. E.; Franz, A.; Frawley, A. D.; Fukao, Y.; Fung, S. -Y; Gadrat, S.; Germain, M.; Glenn, A.; Gonin, M.; Gosset, J.; Goto, Y.; de Cassagnac, R. Granier; Grau, N.; Greene, S. V.; Perdekamp, M. Grosse; Gustafsson, H. -A; Hachiya, T.; Haggerty, J. S.; Hamagaki, H.; Hansen, A. G.; Hartouni, E. P.; Harvey, M.; Hasuko, K.; Hayano, R.; He, X.; Heffner, M.; Hemmick, T. K.; Heuser, J. M.; Hidas, P.; Hiejima, H.; Hill, J. C.; Hobbs, R.; Holzmann, W.; Homma, K.; Hong, B.; Hoover, A.; Horaguchi, T.; Ichihara, T.; Ikonnikov, V. V.; Imai, K.; Inaba, M.; Inuzuka, M.; Isenhower, D.; Isenhower, L.; Ishihara, M.; Issah, M.; Isupov, A.; Jacak, B. V.; Jia, J.; Jinnouchi, O.; Johnson, B. M.; Johnson, S. C.; Joo, K. S.; Jouan, D.; Kajihara, F.; Kametani, S.; Kamihara, N.; Kaneta, M.; Kang, J. H.; Katou, K.; Kawabata, T.; Kazantsev, A. V.; Kelly, S.; Khachaturov, B.; Khanzadeev, A.; Kikuchi, J.; Kim, D. J.; Kim, E.; Kim, G. -B; Kim, H. J.; Kinney, E.; Kiss, A.; Kistenev, E.; Kiyomichi, A.; Klein-Boesing, C.; Kobayashi, H.; Kochenda, L.; Kochetkov, V.; Kohara, R.; Komkov, B.; Konno, M.; Kotchetkov, D.; Kozlov, A.; Kroon, P. J.; Kuberg, C. H.; Kunde, G. J.; Kurita, K.; Kweon, M. J.; Kwon, Y.; Kyle, G. S.; Lacey, R.; Lajoie, J. G.; Le Bornec, Y.; Lebedev, A.; Leckey, S.; Lee, D. M.; Leitch, M. J.; Leite, M. A. L.; Li, X. H.; Lim, H.; Litvinenko, A.; Liu, M. X.; Maguire, C. F.; Makdisi, Y. I.; Malakhov, A.; Manko, V. I.; Mao, Y.; Martinez, G.; Masui, H.; Matathias, F.; Matsumoto, T.; McCain, M. C.; McGaughey, P. L.; Miake, Y.; Miller, T. E.; Milov, A.; Mioduszewski, Saskia; Mishra, G. C.; Mitchell, J. T.; Mohanty, A. K.; Morrison, D. P.; Moss, J. M.; Mukhopadhyay, D.; Muniruzzaman, M.; Nagamiya, S.; Nagle, J. L.; Nakamura, T.; Newby, J.; Nyanin, A. S.; Nystrand, J.; O'Brien, E.; Ogilvie, C. A.; Ohnishi, H.; Ojha, I. D.; Okada, H.; Okada, K.; Oskarsson, A.; Otterlund, I.; Oyama, K.; Ozawa, K.; Pal, D.; Palounek, A. P. T.; Pantuev, V.; Papavassiliou, V.; Park, J.; Park, W. J.; Pate, S. F.; Pei, H.; Penev, V.; Peng, J. -C; Pereira, H.; Peresedov, V.; Pierson, A.; Pinkenburg, C.; Pisani, R. P.; Purschke, M. L.; Purwar, A. K.; Qualls, J. M.; Rak, J.; Ravinovich, I.; Read, K. F.; Reuter, M.; Reygers, K.; Riabov, V.; Riabov, Y.; Roche, G.; Romana, A.; Rosati, M.; Rosendahl, S. S. E.; Rosnet, P.; Rykov, V. L.; Ryu, S. S.; Saito, N.; Sakaguchi, T.; Sakai, S.; Samsonov, V.; Sanfratello, L.; Santo, R.; Sato, H. D.; Sato, S.; Sawada, S.; Schutz, Y.; Semenov, V.; Seto, R.; Shea, T. K.; Shein, I.; Shibata, T. -A; Shigaki, K.; Shimomura, M.; Sickles, A.; Silva, C. L.; Silvermyr, D.; Sim, K. S.; Soldatov, A.; Soltz, R. A.; Sondheim, W. E.; Sorensen, S. P.; Sourikova, I. V.; Staley, F.; Stankus, P. W.; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, S. P.; Sugitate, T.; Sullivan, J. P.; Takagi, S.; Takagui, E. M.; Taketani, A.; Tanaka, K. H.; Tanaka, Y.; Tanida, K.; Tannenbaum, M. J.; Taranenko, A.; Tarjan, P.; Thomas, T. L.; Togawa, M.; Tojo, J.; Torii, H.; Towell, R. S.; Tram, V-N; Tserruya, I.; Tsuchimoto, Y.; Tydesjo, H.; Tyurin, N.; Uam, T. J.; van Hecke, H. W.; Velkovska, J.; Velkovsky, M.; Veszpremi, V.; Vinogradov, A. A.; Volkov, M. A.; Vznuzdaev, E.; Wang, X. R.; Watanabe, Y.; White, S. N.; Willis, N.; Wohn, F. K.; Woody, C. L.; Xie, W.; Yanovich, A.; Yokkaichi, S.; Young, G. R.; Yushmanov, I. E.; Zajc, W. A.; Zhang, C.; Zhou, S.; Zimanyi, J.; Zolin, L.; Zong, X.; PHENIX Collaboration.

    2006-01-01

    To study heavy ion collisions at energies available from the Relativistic Heavy Ion Collider (RHIC), we have developed a multiphase transport model that includes both initial partonic and final hadronic interactions. ...

  15. Fragmentation and Hadronization

    E-Print Network [OSTI]

    B. R. Webber

    1999-12-10

    Experimental data, theoretical ideas and models concerning jet fragmentation and the hadronization process are reviewed, concentrating on the following topics: factorization and small-x resummation of fragmentation functions, hadronization models, single-particle yields and spectra in Z decay, comparisons between quark and gluon jets, current and target fragmentation in deep inelastic scattering, heavy quark fragmentation, Bose-Einstein correlations and WW fragmentation.

  16. Search for heavy resonances decaying into the fully hadronic di-tau final state with the ATLAS detector

    E-Print Network [OSTI]

    Morgenstern, Marcus Matthias

    The discovery of a heavy neutral particle would be a direct hint for new physics beyond the Standard Model. In this thesis searches for new heavy neutral particles decaying into two tau leptons, which further decay into hadrons, are presented. They cover neutral Higgs bosons in the context of the minimal supersymmetric extension of the Standard Model (MSSM) as well as $Z'$ bosons, predicted by various theories with an extended gauge sector. Both analyses are based on the full 2012 proton-proton collision dataset taken by the ATLAS experiment at the Large Hadron Collider (LHC). The extended Higgs sector in the MSSM suggests additional heavy neutral Higgs bosons which decay into tau leptons in about 10\\% of the time. Given that the dominant final state, $\\phi\\to b\\bar{b}$, suffers from tremendous QCD initiated backgrounds, the decay into two tau leptons is the most promising final state to discover such new resonances. The fully hadronic final state is the dominant one with a branching fraction of about 42\\%. I...

  17. Measurement of the charged-hadron spectra and nuclear modification factor in lead-lead collisions with the ATLAS detector

    E-Print Network [OSTI]

    Balek, Petr; The ATLAS collaboration

    2015-01-01

    The ATLAS experiment at the Large Hadron Collider (LHC) measures charged hadron spectra obtained in 2010 and 2011 lead-lead LHC data taking periods with total integrated statistics of 0.15nb${}^{-1}$. The results are compared to the pp spectra of charged hadrons at the same centre-of-mass energy based on the data sample with integrated luminosity of 4.2pb${}^{-1}$ obtained by the ATLAS experiment in 2011 and 2013. These allows for a detailed comparison of the two collision systems in a wide transverse momentum ($0.5 < p_\\mathrm{T} < 150$GeV) and pseudorapidity ($|\\eta|<2$) ranges in different centrality intervals of Pb+Pb collision. The nuclear modification factor $R_\\mathrm{AA}$ is presented in detail as a function of centrality, $p_\\mathrm{T}$ and $\\eta$. It shows a distinct $p_\\mathrm{T}$-dependence with a pronounced minimum at about 7GeV. Above 60GeV, it is consistent with a flat, centrality-dependent, value within the uncertainties. The value is $0.55\\pm0.01(stat.)\\pm0.04(syst.)$ in the most cen...

  18. Measurement of the charged hadron spectra and nuclear modification factor in lead-lead collisions with the ATLAS detector

    E-Print Network [OSTI]

    Balek, Petr; The ATLAS collaboration

    2015-01-01

    The ATLAS experiment at the Large Hadron Collider (LHC) measures charged hadron spectra obtained in 2010-2011 lead-lead LHC data taking periods with total integrated statistics of 0.15 nb${}^{-1}$. The results are compared to the pp spectra of charged hadrons at the same centre-of-mass energy based on the data sample with integrated luminosity of 4 pb${}^{-1}$ obtained by the ATLAS experiment in 2013. These allows for a detailed comparison of the two collision systems in a wide transverse momentum ($0.5< p_\\mathrm{T}<150$ GeV) and pseudorapidity ($|\\eta|<2$) ranges in different centrality intervals of Pb+Pb collision. The nuclear modification factors $R_\\mathrm{AA}$ and $R_\\mathrm{CP}$ are presented in detail as a function of centrality, $p_\\mathrm{T}$ and $\\eta$. They show a distinct $p_\\mathrm{T}$-dependence with a pronounced minimum at about 7GeV. Above 60GeV, $R_\\mathrm{AA}$ is consistent with a flat, centrality-dependent, value within the uncertainties. The value is 0.55±0.01(stat.)±0.04(syst....

  19. Muon Colliders and Neutrino Factories

    SciTech Connect (OSTI)

    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.

  20. Muon colliders and neutrino factories

    SciTech Connect (OSTI)

    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.

  1. Colliding Nuclei at High Energy

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08

    Physicist Peter Steinberg explains what happens when atomic nucleii travelling at close to the speed of light smash together in Brookhaven Lab's Relativistic Heavy Ion Collider (RHIC).

  2. Ordinary and Extraordinary Hadrons

    E-Print Network [OSTI]

    R. L. Jaffe

    2007-01-05

    Resonances and enhancements in meson-meson scattering can be divided into two classes distinguished by their behavior as the number of colors N_c in QCD becomes large: The first are ordinary mesons that become stable as N_c goes to infinity. This class includes textbook q-bar q mesons as well as glueballs and hybrids. The second class, extraordinary mesons, are enhancements that disappear as N_c goes to infinity; they subside into the hadronic continuum. This class includes indistinct and controversial objects that have been classified as q-bar q-bar q q mesons or meson-meson molecules. Pelaez's study of the N_c dependence of unitarized chiral dynamics illustrates both classes: the p-wave pi-pi and K-pi resonances, the rho(770) and K*(892), behave as ordinary mesons; the s-wave pi-pi and K-pi enhancements, the sigma(600) and kappa(800), behave like extraordinary mesons. Ordinary mesons resemble Feshbach resonances while extraordinary mesons look more like effects due to potentials in meson-meson scattering channels. I build and explore toy models along these lines. Finally I discuss some related dynamical issues affecting the interpretation of extraordinary mesons.

  3. Scaling properties of fractional momentum loss of high-pT hadrons in nucleus-nucleus collisions at $\\sqrt{s_{_{NN}}}$ from 62.4 GeV to 2.76 TeV

    E-Print Network [OSTI]

    Adare, A; Aidala, C; Ajitanand, N N; Akiba, Y; Akimoto, R; Al-Bataineh, H; Alexander, J; Alfred, M; Al-Ta'ani, H; Angerami, A; Aoki, K; Apadula, N; Aphecetche, L; Aramaki, Y; Armendariz, R; Aronson, S H; Asai, J; Asano, H; Aschenauer, E C; Atomssa, E T; Averbeck, R; Awes, T C; Azmoun, B; Babintsev, V; Bai, M; Baksay, G; Baksay, L; Baldisseri, A; Bandara, N S; Bannier, B; Barish, K N; Barnes, P D; Bassalleck, B; Basye, A T; Bathe, S; Batsouli, S; Baublis, V; Baumann, C; Baumgart, S; Bazilevsky, A; Beaumier, M; Beckman, S; Belikov, S; Belmont, R; Bennett, R; Berdnikov, A; Berdnikov, Y; Bickley, A A; Blau, D S; Boissevain, J G; Bok, J S; Borel, H; Boyle, K; Brooks, M L; Bryslawskyj, J; Buesching, H; Bumazhnov, V; Bunce, G; Butsyk, S; Camacho, C M; Campbell, S; Castera, P; Chang, B S; Charvet, J -L; Chen, C -H; Chernichenko, S; Chi, C Y; Chiba, J; Chiu, M; Choi, I J; Choi, J B; Choi, S; Choudhury, R K; Christiansen, P; Chujo, T; Chung, P; Churyn, A; Chvala, O; Cianciolo, V; Citron, Z; Cleven, C R; Cole, B A; Comets, M P; Connors, M; Constantin, P; Csanád, M; Csörg?, T; Dahms, T; Dairaku, S; Danchev, I; Danley, D; Das, K; Datta, A; Daugherity, M S; David, G; Deaton, M B; DeBlasio, K; Dehmelt, K; Delagrange, H; Denisov, A; d'Enterria, D; Deshpande, A; Desmond, E J; Dharmawardane, K V; Dietzsch, O; Ding, L; Dion, A; Diss, P B; Do, J H; Donadelli, M; D'Orazio, L; Drapier, O; Drees, A; Drees, K A; Dubey, A K; Durham, J M; Durum, A; Dutta, D; Dzhordzhadze, V; Edwards, S; Efremenko, Y V; Egdemir, J; Ellinghaus, F; Emam, W S; Engelmore, T; Enokizono, A; En'yo, H; Esumi, S; Eyser, K O; Fadem, B; Feege, N; Fields, D E; Finger, M; Jr., \\,; Fleuret, F; Fokin, S L; Fraenkel, Z; Frantz, J E; Franz, A; Frawley, A D; Fujiwara, K; Fukao, Y; Fusayasu, T; Gadrat, S; Gainey, K; Gal, C; Gallus, P; Garg, P; Garishvili, A; Garishvili, I; Ge, H; Giordano, F; Glenn, A; Gong, H; Gong, X; Gonin, M; Gosset, J; Goto, Y; de Cassagnac, R Granier; Grau, N; Greene, S V; Perdekamp, M Grosse; Gunji, T; Guo, L; Gustafsson, H -Å; Hachiya, T; Henni, A Hadj; Haegemann, C; Haggerty, J S; Hahn, K I; Hamagaki, H; Hamblen, J; Hamilton, H F; Han, R; Han, S Y; Hanks, J; Harada, H; Hartouni, E P; Haruna, K; Hasegawa, S; Haseler, T O S; Hashimoto, K; Haslum, E; Hayano, R; He, X; Heffner, M; Hemmick, T K; Hester, T; Hiejima, H; Hill, J C; Hobbs, R; Hohlmann, M; Hollis, R S; Holzmann, W; Homma, K; Hong, B; Horaguchi, T; Hori, Y; Hornback, D; Hoshino, T; Hotvedt, N; Huang, J; Huang, S; Ichihara, T; Ichimiya, R; Ide, J; Iinuma, H; Ikeda, Y; Imai, K; Imrek, J; Inaba, M; Inoue, Y; Iordanova, A; Isenhower, D; Isenhower, L; Ishihara, M; Isobe, T; Issah, M; Isupov, A; Ivanishchev, D; Jacak, B V; Javani, M; Jezghani, M; Jia, J; Jiang, X; Jin, J; Jinnouchi, O; Johnson, B M; Joo, K S; Jouan, D; Jumper, D S; Kajihara, F; Kametani, S; Kamihara, N; Kamin, J; Kanda, S; Kaneta, M; Kaneti, S; Kang, B H; Kang, J H; Kang, J S; Kanou, H; Kapustinsky, J; Karatsu, K; Kasai, M; Kawall, D; Kawashima, M; Kazantsev, A V; Kempel, T; Key, J A; Khachatryan, V; Khanzadeev, A; Kijima, K M; Kikuchi, J; Kim, B I; Kim, C; Kim, D H; Kim, D J; Kim, E; Kim, E -J; Kim, G W; Kim, H J; Kim, K -B; Kim, M; Kim, S H; Kim, Y -J; Kim, Y K; Kimelman, B; Kinney, E; Kiriluk, K; Kiss, Á; Kistenev, E; Kitamura, R; Kiyomichi, A; Klatsky, J; Klay, J; Klein-Boesing, C; Kleinjan, D; Kline, P; Koblesky, T; Kochenda, L; Kochetkov, V; Komatsu, Y; Komkov, B; Konno, M; Koster, J; Kotchetkov, D; Kotov, D; Kozlov, A; Král, A; Kravitz, A; Krizek, F; Kubart, J; Kunde, G J; Kurihara, N; Kurita, K; Kurosawa, M; Kweon, M J; Kwon, Y; Kyle, G S; Lacey, R; Lai, Y S; Lajoie, J G; Lebedev, A; Lee, B; Lee, D M; Lee, J; Lee, K; Lee, K B; Lee, K S; Lee, M K; Lee, S; Lee, S H; Lee, S R; Lee, T; Leitch, M J; Leite, M A L; Leitgab, M; Leitner, E; Lenzi, B; Lewis, B; Li, X; Liebing, P; Lim, S H; Levy, L A Linden; Liška, T; Litvinenko, A; Liu, H; Liu, M X; Love, B; Luechtenborg, R; Lynch, D; Maguire, C F; Makdisi, Y I; Makek, M; Malakhov, A; Malik, M D; Manion, A; Manko, V I; Mannel, E; Mao, Y; Mašek, L; Masui, H; Masumoto, S; Matathias, F; McCumber, M; McGaughey, P L; McGlinchey, D; McKinney, C; Means, N; Meles, A; Mendoza, M; Meredith, B; Miake, Y; Mibe, T; Mignerey, A C; Mikeš, P; Miki, K; Miller, T E; Milov, A; Mioduszewski, S; Mishra, D K; Mishra, M; Mitchell, J T; Mitrovski, M; Miyachi, Y; Miyasaka, S; Mizuno, S; Mohanty, A K; Mohapatra, S; Montuenga, P; Moon, H J; Moon, T; Morino, Y; Morreale, A; Morrison, D P; Motschwiller, S; Moukhanova, T V; Mukhopadhyay, D; Murakami, T; Murata, J; Mwai, A; Nagae, T; Nagamiya, S; Nagashima, K; Nagata, Y; Nagle, J L; Naglis, M; Nagy, M I; Nakagawa, I; Nakagomi, H; Nakamiya, Y; Nakamura, K R; Nakamura, T; Nakano, K; Nattrass, C; Nederlof, A; Netrakanti, P K; Newby, J; Nguyen, M; Nihashi, M; Niida, T; Nishimura, S; Norman, B E; Nouicer, R; Novak, T; Novitzky, N; Nyanin, A S; O'Brien, E; Oda, S X

    2015-01-01

    Measurements of the fractional momentum loss ($S_{\\rm loss}\\equiv{\\delta}p_T/p_T$) of high-transverse-momentum-identified hadrons in heavy ion collisions are presented. Using $\\pi^0$ in Au$+$Au and Cu$+$Cu collisions at $\\sqrt{s_{_{NN}}}=62.4$ and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb$+$Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of $S_{\\rm loss}$ as a function of a number of variables: the number of participants, $N_{\\rm part}$, the number of quark participants, $N_{\\rm qp}$, the charged-particle density, $dN_{\\rm ch}/d\\eta$, and the Bjorken energy density times the equilibration time, $\\varepsilon_{\\rm Bj}\\tau_{0}$. We find that the $p_T$ where $S_{\\rm loss}$ has its maximum, varies both with centrality and collision energy. Above the maximum, $S_{\\rm loss}$ tends to follow a power-law function with all four scaling variables. The data at $\\sqrt{s_{_{NN}}}$=200 GeV and ...

  4. Scaling properties of fractional momentum loss of high-pT hadrons in nucleus-nucleus collisions at $\\sqrt{s_{_{NN}}}$ from 62.4 GeV to 2.76 TeV

    E-Print Network [OSTI]

    A. Adare; S. Afanasiev; C. Aidala; N. N. Ajitanand; Y. Akiba; R. Akimoto; H. Al-Bataineh; J. Alexander; M. Alfred; H. Al-Ta'ani; A. Angerami; K. Aoki; N. Apadula; L. Aphecetche; Y. Aramaki; R. Armendariz; S. H. Aronson; J. Asai; H. Asano; E. C. Aschenauer; E. T. Atomssa; R. Averbeck; T. C. Awes; B. Azmoun; V. Babintsev; M. Bai; G. Baksay; L. Baksay; A. Baldisseri; N. S. Bandara; B. Bannier; K. N. Barish; P. D. Barnes; B. Bassalleck; A. T. Basye; S. Bathe; S. Batsouli; V. Baublis; C. Baumann; S. Baumgart; A. Bazilevsky; M. Beaumier; S. Beckman; S. Belikov; R. Belmont; R. Bennett; A. Berdnikov; Y. Berdnikov; A. A. Bickley; D. S. Blau; J. G. Boissevain; J. S. Bok; H. Borel; K. Boyle; M. L. Brooks; J. Bryslawskyj; H. Buesching; V. Bumazhnov; G. Bunce; S. Butsyk; C. M. Camacho; S. Campbell; P. Castera; B. S. Chang; J. -L. Charvet; C. -H. Chen; S. Chernichenko; C. Y. Chi; J. Chiba; M. Chiu; I. J. Choi; J. B. Choi; S. Choi; R. K. Choudhury; P. Christiansen; T. Chujo; P. Chung; A. Churyn; O. Chvala; V. Cianciolo; Z. Citron; C. R. Cleven; B. A. Cole; M. P. Comets; M. Connors; P. Constantin; M. Csanád; T. Csörg?; T. Dahms; S. Dairaku; I. Danchev; D. Danley; K. Das; A. Datta; M. S. Daugherity; G. David; M. B. Deaton; K. DeBlasio; K. Dehmelt; H. Delagrange; A. Denisov; D. d'Enterria; A. Deshpande; E. J. Desmond; K. V. Dharmawardane; O. Dietzsch; L. Ding; A. Dion; P. B. Diss; J. H. Do; M. Donadelli; L. D'Orazio; O. Drapier; A. Drees; K. A. Drees; A. K. Dubey; J. M. Durham; A. Durum; D. Dutta; V. Dzhordzhadze; S. Edwards; Y. V. Efremenko; J. Egdemir; F. Ellinghaus; W. S. Emam; T. Engelmore; A. Enokizono; H. En'yo; S. Esumi; K. O. Eyser; B. Fadem; N. Feege; D. E. Fields; M. Finger; M. Finger; \\, Jr.; F. Fleuret; S. L. Fokin; Z. Fraenkel; J. E. Frantz; A. Franz; A. D. Frawley; K. Fujiwara; Y. Fukao; T. Fusayasu; S. Gadrat; K. Gainey; C. Gal; P. Gallus; P. Garg; A. Garishvili; I. Garishvili; H. Ge; F. Giordano; A. Glenn; H. Gong; X. Gong; M. Gonin; J. Gosset; Y. Goto; R. Granier de Cassagnac; N. Grau; S. V. Greene; M. Grosse Perdekamp; T. Gunji; L. Guo; H. -Å. Gustafsson; T. Hachiya; A. Hadj Henni; C. Haegemann; J. S. Haggerty; K. I. Hahn; H. Hamagaki; J. Hamblen; H. F. Hamilton; R. Han; S. Y. Han; J. Hanks; H. Harada; E. P. Hartouni; K. Haruna; S. Hasegawa; T. O. S. Haseler; K. Hashimoto; E. Haslum; R. Hayano; X. He; M. Heffner; T. K. Hemmick; T. Hester; H. Hiejima; J. C. Hill; R. Hobbs; M. Hohlmann; R. S. Hollis; W. Holzmann; K. Homma; B. Hong; T. Horaguchi; Y. Hori; D. Hornback; T. Hoshino; N. Hotvedt; J. Huang; S. Huang; T. Ichihara; R. Ichimiya; J. Ide; H. Iinuma; Y. Ikeda; K. Imai; J. Imrek; M. Inaba; Y. Inoue; A. Iordanova; D. Isenhower; L. Isenhower; M. Ishihara; T. Isobe; M. Issah; A. Isupov; D. Ivanishchev; B. V. Jacak; M. Javani; M. Jezghani; J. Jia; X. Jiang; J. Jin; O. Jinnouchi; B. M. Johnson; K. S. Joo; D. Jouan; D. S. Jumper; F. Kajihara; S. Kametani; N. Kamihara; J. Kamin; S. Kanda; M. Kaneta; S. Kaneti; B. H. Kang; J. H. Kang; J. S. Kang; H. Kanou; J. Kapustinsky; K. Karatsu; M. Kasai; D. Kawall; M. Kawashima; A. V. Kazantsev; T. Kempel; J. A. Key; V. Khachatryan; A. Khanzadeev; K. M. Kijima; J. Kikuchi; B. I. Kim; C. Kim; D. H. Kim; D. J. Kim; E. Kim; E. -J. Kim; G. W. Kim; H. J. Kim; K. -B. Kim; M. Kim; S. H. Kim; Y. -J. Kim; Y. K. Kim; B. Kimelman; E. Kinney; K. Kiriluk; Á. Kiss; E. Kistenev; R. Kitamura; A. Kiyomichi; J. Klatsky; J. Klay; C. Klein-Boesing; D. Kleinjan; P. Kline; T. Koblesky; L. Kochenda; V. Kochetkov; Y. Komatsu; B. Komkov; M. Konno; J. Koster; D. Kotchetkov; D. Kotov; A. Kozlov; A. Král; A. Kravitz; F. Krizek; J. Kubart; G. J. Kunde; N. Kurihara; K. Kurita; M. Kurosawa; M. J. Kweon; Y. Kwon; G. S. Kyle; R. Lacey; Y. S. Lai; J. G. Lajoie; A. Lebedev; B. Lee; D. M. Lee; J. Lee; K. Lee; K. B. Lee; K. S. Lee; M. K. Lee; S Lee; S. H. Lee; S. R. Lee; T. Lee; M. J. Leitch; M. A. L. Leite; M. Leitgab; E. Leitner; B. Lenzi; B. Lewis; X. Li; P. Liebing; S. H. Lim; L. A. Linden Levy; T. Liška; A. Litvinenko; H. Liu; M. X. Liu; B. Love; R. Luechtenborg; D. Lynch; C. F. Maguire; Y. I. Makdisi; M. Makek; A. Malakhov; M. D. Malik; A. Manion; V. I. Manko; E. Mannel; Y. Mao; L. Mašek; H. Masui; S. Masumoto; F. Matathias; M. McCumber; P. L. McGaughey; D. McGlinchey; C. McKinney; N. Means; A. Meles; M. Mendoza; B. Meredith; Y. Miake; T. Mibe; A. C. Mignerey; P. Mikeš; K. Miki; T. E. Miller; A. Milov; S. Mioduszewski; D. K. Mishra; M. Mishra; J. T. Mitchell; M. Mitrovski; Y. Miyachi; S. Miyasaka; S. Mizuno; A. K. Mohanty; S. Mohapatra; P. Montuenga; H. J. Moon; T. Moon; Y. Morino; A. Morreale; D. P. Morrison; S. Motschwiller; T. V. Moukhanova; D. Mukhopadhyay; T. Murakami; J. Murata; A. Mwai; T. Nagae; S. Nagamiya; K. Nagashima; Y. Nagata; J. L. Nagle; M. Naglis; M. I. Nagy; I. Nakagawa; H. Nakagomi; Y. Nakamiya; K. R. Nakamura; T. Nakamura; K. Nakano; C. Nattrass; A. Nederlof

    2015-09-22

    Measurements of the fractional momentum loss ($S_{\\rm loss}\\equiv{\\delta}p_T/p_T$) of high-transverse-momentum-identified hadrons in heavy ion collisions are presented. Using $\\pi^0$ in Au$+$Au and Cu$+$Cu collisions at $\\sqrt{s_{_{NN}}}=62.4$ and 200 GeV measured by the PHENIX experiment at the Relativistic Heavy Ion Collider and and charged hadrons in Pb$+$Pb collisions measured by the ALICE experiment at the Large Hadron Collider, we studied the scaling properties of $S_{\\rm loss}$ as a function of a number of variables: the number of participants, $N_{\\rm part}$, the number of quark participants, $N_{\\rm qp}$, the charged-particle density, $dN_{\\rm ch}/d\\eta$, and the Bjorken energy density times the equilibration time, $\\varepsilon_{\\rm Bj}\\tau_{0}$. We find that the $p_T$ where $S_{\\rm loss}$ has its maximum, varies both with centrality and collision energy. Above the maximum, $S_{\\rm loss}$ tends to follow a power-law function with all four scaling variables. The data at $\\sqrt{s_{_{NN}}}$=200 GeV and 2.76 TeV, for sufficiently high particle densities, have a common scaling of $S_{\\rm loss}$ with $dN_{\\rm ch}/d\\eta$ and $\\varepsilon_{\\rm Bj}\\tau_{0}$, lending insight on the physics of parton energy loss.

  5. The Electron-Ion Collider

    E-Print Network [OSTI]

    V. Guzey

    2009-07-23

    The future Electron-Ion Collider (EIC) is a proposed new facility to collide high-energy electrons with beams of polarized protons/light nuclei and unpolarized nuclei. We overview the goals of the project and key measurements at the EIC. We also briefly comment on recent developments of the project.

  6. Positrons for linear colliders

    SciTech Connect (OSTI)

    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)

  7. International Linear Collider Technical Design Report - Volume...

    Office of Scientific and Technical Information (OSTI)

    Technical Report: International Linear Collider Technical Design Report - Volume 2: Physics Citation Details In-Document Search Title: International Linear Collider Technical...

  8. $WWZ/?$ production in large extra dimensions model at LHC and ILC

    E-Print Network [OSTI]

    Li Xiao-Zhou; Duan Peng-Fei; Ma Wen-Gan; Zhang Ren-You; Guo Lei

    2012-11-06

    We investigate the effect induced by the Kaluza-Klein (KK) graviton in the $W^+W^-\\gamma/Z$ production in the framework of the large extra dimensions (LED) model at both the CERN Large Hadron Collider (LHC) and the International Linear Collider (ILC). The integrated cross sections and various kinematic distributions in the LED model are presented and compared with those in the standard model. The results show that the contributions from KK-graviton exchange remarkably affect the observables of the triple gauge boson ($W^+W^-\\gamma/Z$) production processes at both the ILC and the LHC, particularly either in the high transverse momentum region or in the central rapidity region. We also find that the relative LED discrepancy for the $W^+W^-\\gamma/Z$ production at the LHC is generally larger than that at the ILC due to the additional LED contribution via $gg$ fusion subprocess and the KK-graviton exchanging resonant effect induced by the continuous large colliding energy in $pp$ collision. We conclude that the $W^{+}W^{-}\\gamma$ and $W^{+}W^{-}Z$ productions at the LHC could have the distinct advantage over at the ILC from the aspect of effectively exploring the LED signal in measuring $W^+W^-\\gamma/Z$ production.

  9. Determination of Dark Matter Properties at High-Energy Colliders

    E-Print Network [OSTI]

    Baltz, Edward A.

    2009-01-01

    at the planned International Linear Collider (ILC) will makecollider, the International Linear Collider (ILC), which

  10. Structure and Dynamics of Colliding Plasma Jets

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

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

    2013-12-01

    Monoenergetic-proton radiographs of laser-generated, high-Mach-number plasma jets colliding at various angles shed light on the structures and dynamics of these collisions. The observations compare favorably with results from 2D hydrodynamic simulations of multistream plasma jets, and also with results from an analytic treatment of electron flow and magnetic field advection. In collisions of two noncollinear jets, the observed flow structure is similar to the analytic model’s prediction of a characteristic feature with a narrow structure pointing in one direction and a much thicker one pointing in the opposite direction. Spontaneous magnetic fields, largely azimuthal around the colliding jets and generatedmore »by the well-known ?Te ×?ne Biermann battery effect near the periphery of the laser spots, are demonstrated to be “frozen in” the plasma (due to high magnetic Reynolds number RM ~5×10?) 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

  11. Structure and Dynamics of Colliding Plasma Jets

    SciTech Connect (OSTI)

    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 ~5×10?) and advected along the jet streamlines of the electron flow. These studies provide novel insight into the interactions and dynamics of colliding plasma jets.

  12. Electron-Ion Collider - taking us to the next QCD frontier

    E-Print Network [OSTI]

    Jian-Wei Qiu

    2014-12-08

    In this talk, I demonstrate that the proposed Electron-Ion Collider (EIC) will be an ideal and unique future facility to address many overarching questions about QCD and strong interaction physics at one place. The EIC will be the world's first polarized electron-proton (and light ion), as well as the first electron-nucleus collider at flexible collision energies. With its high luminosity and beam polarization, the EIC distinguishes itself from HERA and the other fixed target electron-hadron facilities around the world. The EIC is capable of taking us to the next QCD frontier to explore the glue that binds us all.

  13. Higgs-boson production at the Photon Collider at TESLA

    E-Print Network [OSTI]

    Piotr Niezurawski

    2005-03-31

    In this thesis feasibility of the precise measurement of the Higgs-boson production cross section gamma+gamma->higgs->b+bbar at the Photon Collider at TESLA is studied in detail. The study is based on the realistic luminosity spectra simulation. The heavy quark background is estimated using the dedicated code based on NLO QCD calculations. Other background processes, which were neglected in the earlier analyses, are also studied. Also the contribution from the overlaying events, gamma+gamma->hadrons, is taken into account. The non-zero beam crossing angle and the finite size of colliding bunches are included in the event generation. The analysis is based on the full detector simulation with realistic b-tagging, and the criteria of event selection are optimized separately for each considered Higgs-boson mass. For the Standard-Model Higgs boson with mass of 120 to 160 GeV the partial width \\Gamma(h->gamma+gamma)BR(h->b+bbar) can be measured with a statistical accuracy of 2.1-7.7% after one year of the Photon Collider running. The systematic uncertainties of the measurement are estimated to be of the order of 2%. For MSSM Higgs bosons A and H, for M_A=200-350 GeV and tan(beta)=7, the statistical precision of the cross-section measurement is estimated to be 8--34%, for four considered MSSM parameters sets. As heavy neutral Higgs bosons in this scenario may not be discovered at LHC or at the first stage of the e+e- collider, an opportunity of being a discovery machine is also studied for the Photon Collider.

  14. Hadronic physics in peripheral heavy ion collisions

    E-Print Network [OSTI]

    A. A. Natale

    2002-01-22

    We discuss the production of hadronic resonances in very peripheral heavy ion collisions, where the ions collide with impact parameter larger than twice the nuclear radius and remain intact after the collision. We compare the resonance production through two-photon and double Pomeron exchange, showing that when we impose the condition for a peripheral interaction the $\\gamma \\gamma$ process dominates over the Pomeron interaction, due to the short range propagation of this last one. We also discuss the observation of light resonances through the subprocess $\\gamma \\gamma \\to R \\to \\gamma \\gamma $, which is a clean signal for glueball candidates as well as one way to check the existence of a possible scalar $\\sigma$ meson.

  15. Top quark anomalous couplings at the International Linear Collider

    E-Print Network [OSTI]

    Erik Devetak; Andrei Nomerotski; Michael Peskin

    2011-07-27

    We present a study of the experimental determination of the forward-backward asymmetry in the process $e^+e^-\\to t\\bar t$ and in the subsequent $t\\to Wb$ decay, studied in the context of the International Linear Collider. This process probes the elementary couplings of the top quark to the photon, the $Z$ and the $W$ bosons at a level of precision that is difficult to achieve at hadron colliders. Measurement of the forward-backward asymmetry requires excellent $b$ quark identification and determination of the quark charge. The study reported here is performed in the most challenging all-hadronic channel $e^+e^- \\to b\\bar b q\\bar q q\\bar q$. It includes realistic details of the experimental environment, a full Monte Carlo simulation of the detector, based on the Silicon Detector concept, and realistic event reconstruction. The forward-backward asymmetries are determined to a precision of approximately 1% for each of two choices of beam polarization. We analyze the implications for the determination of the $t\\bar t Z$ and $Wtb$ couplings.

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

    SciTech Connect (OSTI)

    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.

  17. Physics at the International Linear Collider

    E-Print Network [OSTI]

    J. List

    2006-05-18

    The International Linear Collider (ILC) is the next large project in accelerator based particle physics. It is complementary to the LHC in many aspects. Measurements from both machines together will finally shed light onto the known deficiencies of the Standard Model of particle physics and allow to unveil a possible underlying more fundamental theory. Here, the possibilities of the ILC will be discussed with special emphasis on the Higgs sector and on topics with a strong connection to cosmological questions like extra dimensions or dark matter candidates.

  18. Large Higgs energy region in Higgs associated top pair production...

    Office of Scientific and Technical Information (OSTI)

    Large Higgs energy region in Higgs associated top pair production at the Linear Collider Citation Details In-Document Search Title: Large Higgs energy region in Higgs associated...

  19. Dynamical generation of hadronic resonances

    E-Print Network [OSTI]

    Thomas Wolkanowski

    2014-10-26

    One type of dynamical generation consists in the formation of multiple hadronic resonances from single seed states by incorporating hadronic loop contributions on the level of $s$-wave propagators. Along this line, we study the propagator poles within two models of scalar resonances and report on the status of our work: (i) Using a simple quantum field theory describing the decay of $f_{0}(500)$ into two pions, we may obtain a second, additional pole on the first Riemann sheet below the pion-pion threshold (i.e., a stable state can emerge). (ii) We perform a numerical study of the pole(s) of $a_{0}(1450)$ by using as an input the results obtained in the extended Linear Sigma Model (eLSM). Here, we do not find any additional pole besides the original one, thus we cannot obtain $a_{0}(980)$ as an emerging state. (iii) We finally demonstrate that, although the coupling constants in typical effective models might be large, the next-to-leading-order contribution to the decay amplitude is usually small and can be neglected.

  20. Systematics of the charged-hadron P_T spectrum and the nuclear suppression factor in heavy-ion collisions from sqrt{s}=200 GeV to sqrt{s} =2.76 TeV

    E-Print Network [OSTI]

    Thorsten Renk; Hannu Holopainen; Risto Paatelainen; Kari J. Eskola

    2011-06-01

    In this paper, our goal is to make a simultaneous analysis of the high- and low-P_T parts of the charged-hadron P_T spectrum measured by the ALICE collaboration in central Pb-Pb collisions at sqrt{s}=2.76 TeV at the Large Hadron Collider (LHC), based on models which have been successfully applied and constrained in Au-Au collisions at Relativistic Heavy Ion Collider (RHIC). For the hydrodynamical modeling with which we obtain the low-P_T spectrum, we have computed the initial conditions based on perturbative QCD (pQCD) minijet production and saturation. The sensitivity of the obtained charged-hadron P_T spectrum on the hydrodynamic model parameters is studied. For the high-P_T part, we apply a number of parton-medium interaction models, which are tuned to describe the nuclear suppression factor R_AA measured at the RHIC in central Au-Au collisions at sqrt{s}=200 GeV. We find that the higher kinematic reach of the LHC, manifest in the hardening of the pQCD parton spectral slope, is in principle very efficient in discriminating the various models. However, due to the uncertainties in the p-p baseline, none of the tested models can be firmly ruled out with the present ALICE data. Comparison with the LHC data in this approach also shows that the matching of the hydrodynamic and pQCD+jet quenching components leaves fairly little room for other hadron production mechanisms in the cross-over region P_T=4-5 GeV.

  1. Rare Hadronic B Decays

    SciTech Connect (OSTI)

    Bevan, A.J.

    2006-06-07

    Rare hadronic B-meson decays allow us to study CP violation. The class of B-decays final states containing two vector mesons provides a rich set of angular correlation observables to study. This article reviews some of the recent experimental results from the BABAR and Belle collaborations.

  2. Hadron Correlation in Jets

    E-Print Network [OSTI]

    Rudolph C. Hwa

    2007-01-18

    We review some recent experimental and theoretical work on the correlation among hadrons produced at intermediate $p_T$ at RHIC. The topics include: forward and backward asymmetry with and without trigger at mid-rapidity, associated-particle distribution on the near side, the $\\Omega$ puzzle and its solution, associated particles on the away side, and two-jet recombination at LHC.

  3. Charmed hadron production at low transverse momentum in Au+Au collisions at RHIC

    E-Print Network [OSTI]

    B. I. Abelev

    2014-04-25

    We report measurements of charmed hadron production from hadronic ($D^{0}\\rightarrow K\\pi$) and semileptonic ($\\mu$ and $e$) decays in 200 GeV Au+Au collisions at RHIC. Analysis of the spectra indicates that charmed hadrons have a different radial flow pattern from light or multi-strange hadrons. Charm cross sections at mid-rapidity are extracted by combining the three independent measurements, covering the transverse momentum range that contributes to $\\sim$90% of the integrated cross section. The cross sections scale with number of binary collisions of the initial nucleons, a signature of charm production exclusively at the initial impact of colliding heavy ions. The implications for charm quark interaction and thermalization in the strongly interacting matter are discussed.

  4. Lattice studies of hadron physics with disconnected quark loops

    E-Print Network [OSTI]

    Takashi Kaneko

    2010-12-13

    Disconnected diagrams give crucial contributions to the physics of flavor singlet hadrons and to scalar form factors of non-singlet hadrons. Naive lattice calculation of the disconnected diagrams, however, requires a huge number of fermion matrix inversions and hence a prohibitively large computational cost. In this article, we present recent studies of the flavor-singelt meson spectrum and nucleon strange quark content using the all-to-all propagator to calculate the relevant disconnected diagrams.

  5. Mass, Spin, and Physics Beyond the Standard Model at Colliders

    E-Print Network [OSTI]

    Klemm, William Lathrop

    2011-01-01

    Proceedings of 2005 International Linear Collider Workshop (of Supersymmetry,” International Linear Collider Workshop (proposed for the International Linear Collider (ILC), it was

  6. Multi-Stage Bunch Compressors for the International Linear Collider

    E-Print Network [OSTI]

    Tenenbaum, Peter G.; Raubenheimer, Tor O.; Wolski, Andrzej

    2005-01-01

    FOR THE INTERNATIONAL LINEAR COLLIDER ? P. Tenenbaum † ,goals, the International Linear Collider (ILC) requires acompressors for the International Linear Collider. Each of

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

    SciTech Connect (OSTI)

    De Lorenzo, Gianluca

    2010-05-01

    This thesis reports on two searches for the production of squarks and gluinos, supersymmetric partners of the Standard Model (SM) quarks and gluons, using the CDF detector at the Tevatron {radical}s = 1.96 TeV p{bar p} collider. An inclusive search for squarks and gluinos pair production is performed in events with large E{sub T} and multiple jets in the final state, based on 2 fb{sup -1} of CDF Run II data. The analysis is performed within the framework of minimal supergravity (mSUGRA) and assumes R-parity conservation where sparticles are produced in pairs. The expected signal is characterized by the production of multiple jets of hadrons from the cascade decays of squarks and gluinos and large missing transverse energy E{sub T} from the lightest supersymmetric particles (LSP). The measurements are in good agreement with SM predictions for backgrounds. The results are translated into 95% confidence level (CL) upper limits on production cross sections and squark and gluino masses in a given mSUGRA scenario. An upper limit on the production cross section is placed in the range between 1 pb and 0.1 pb, depending on the gluino and squark masses considered. The result of the search is negative for gluino and squark masses up to 392 GeV/c{sup 2} in the region where gluino and squark masses are close to each other, gluino masses up to 280 GeV/c{sup 2} regardless of the squark mass, and gluino masses up to 423 GeV=c2 for squark masses below 378 GeV/c{sup 2}. These results are compatible with the latest limits on squark/gluino production obtained by the D0 Collaboration and considerably improve the previous exclusion limits from direct and indirect searches at LEP and the Tevatron. The inclusive search is then extended to a scenario where the pair production of sbottom squarks is dominant. The new search is performed in a generic MSSM scenario with R-parity conservation. A specific SUSY particle mass hierarchy is assumed such that the sbottom decays exclusively as {tilde b}{sub 1} {yields} b{sub {tilde {chi}}{sub 1}{sup 0}}. The expected signal for direct sbottom pair production is characterized by the presence of two jets of hadrons from the hadronization of the bottom quarks and E=T from the two LSPs in the final state. The events are selected with large E{sub T} and two energetic jets in the final state, and at least one jet is required to be associated with a b quark. The measurements are in good agreement with SM predictions for backgrounds. The results are translated into 95% CL exclusion limits on production cross sections and sbottom and neutralino masses in the given MSSM scenario. Cross sections down to 0.1 pb are excluded for the sbottom mass range considered. Sbottom masses up to 230 GeV/c{sup 2} are excluded at 95% CL for neutralino masses below 70 GeV/c{sup 2}. This analysis increases the previous CDF limit by more than 40 GeV/c{sup 2}. The sensitivity of both the inclusive and the exclusive search is dominated by systematic effects and the results of the two analyses can be considered as conclusive for CDF Run II. With the new energy frontier of the newly commissioned Large Hadron Collider in Geneva, the experience from Tevatron will be of crucial importance in the developing of effective strategies to search for SUSY in the next era of particle physics experiments.

  8. Hadrons and Chiral Symmetry

    E-Print Network [OSTI]

    Thomas D. Cohen

    2009-11-16

    These lectures discuss the question of whether a key feature is seen in hadron spectroscopy--the near degeneracy of hadrons with different parity and/or spin. It has been conjectured that this is due to an effective restoration of chiral symmetry. The conjecture is that while these states are, of course, in the symmetry-broken (Nambu-Goldstone) phase, as one goes higher in the spectrum the states become progressively less sensitive to the dynamics of chiral symmetry breaking. These lectures discuss the current status of this conjecture. The motivations for the conjecture are discussed, as is evidence--both theoretical and experimental--in its favor. Possible alternative explanations for the data are also discussed.

  9. Hadronic Final States

    E-Print Network [OSTI]

    B. R. Webber

    1995-10-12

    The following aspects of hadronic final states in deep inelastic lepton scattering are reviewed: measuring $alpha_s$ from multi-jet production rates and event shapes; alternative jet algorithms for DIS; power-suppressed corrections to event shapes; comparing jet fragmentation in $e^+e^-$ annihilation and DIS; final states in the BFKL and CCFM formulations of small-$x$ dynamics; exotic (instanton-induced) final states.

  10. Colliding axisymmetric pp-waves

    E-Print Network [OSTI]

    B. V. Ivanov

    1997-10-21

    An exact solution is found describing the collision of axisymmetric pp-waves with M=0. They are impulsive in character and their coordinate singularities become point curvature singularities at the boundaries of the interaction region. The solution is conformally flat. Concrete examples are given, involving an ultrarelativistic black hole against a burst of pure radiation or two colliding beam- like waves.

  11. Muon Colliders: The Next Frontier

    ScienceCinema (OSTI)

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

    2010-01-08

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

  12. Search for squark production in events with jets, hadronically decaying tau leptons and missing transverse energy at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Abazov, V.M.; /Dubna, JINR; Abbott, B.; /Oklahoma U.; Abolins, M.; /Michigan State U.; Acharya, B.S.; /Tata Inst.; Adams, M.; /Illinois U., Chicago; Adams, T.; /Florida State U.; Aguilo, E.; /Alberta U. /Simon Fraser U. /York U., Canada /McGill U.; Ahsan, M.; /Kansas State U.; Alexeev, G.D.; /Dubna, JINR; Alkhazov, G.; /St. Petersburg, INP; Alton, A.; /Michigan U. /Northeastern U.

    2009-05-01

    A search for supersymmetric partners of quarks is performed in the topology of multijet events accompanied by at least one tau lepton decaying hadronically and large missing transverse energy. Approximately 1 fb-1 of ppbar collision data from the Fermilab Tevatron Collider at a center of mass energy of 1.96 TeV recorded by the D0 detector is analyzed. Results are combined with the previously published D0 inclusive search for squarks and gluinos. No evidence of physics beyond the standard model is found and lower limits on the squark mass up to 410 GeV are derived in the framework of minimal supergravity with tan(beta)=15, A{sub 0}=-2m{sub 0} and mu<0, in the region where decays to tau leptons dominate. Gaugino masses m{sub 1/2} are excluded up to 172 GeV.

  13. Physics at high energy photon photon colliders

    SciTech Connect (OSTI)

    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.

  14. Proceedings of the International Linear Collider Workshop

    E-Print Network [OSTI]

    Proceedings of the International Linear Collider Workshop LCWS 2007 ILC 2007 Volume 1 Edited by Ariane Frey Sabine Riemann #12;Impressum Proceedings of the International Linear Collider Workshop LCWS

  15. High energy hadron-hadron collisions. [Dept. of Physics and Astronomy, Univ. of Georgia, Athens, Georgia

    SciTech Connect (OSTI)

    Chou, T.T.

    1992-01-01

    Results of a study on high energy collisions with the geometrical model are summarized in three parts: (1) the elastic hadron-hadron collision, (2) the inelastic hadron-hadron collision, and (3) e[sup +]e[sup [minus

  16. Muon Collider Physics at Very High Energies

    E-Print Network [OSTI]

    M. S. Berger

    2000-01-03

    Muon colliders might greatly extend the energy frontier of collider physics. One can contemplate circular colliders with center-of-mass energies in excess of 10 TeV. Some physics issues that might be relevant at such a machine are discussed.

  17. Energy dependence of hadron spectra and multiplicities in p+p interactions

    E-Print Network [OSTI]

    Pu?awski, Szymon

    2015-01-01

    The NA61/SHINE experiment at the CERN SPS aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. In order to reach these goals measurements of hadron production properties are performed in nucleus-nucleus, proton-proton and proton-nucleus interactions as a function of collision energy and size of the colliding nuclei. Inclusive spectra of identified hadrons in p+p interactions at the SPS energies are presented as a function of transverse momentum, transverse mass and rapidity. The results are compared with the world data and theoretical models.

  18. Energy dependence of hadron spectra and multiplicities in p+p interactions

    E-Print Network [OSTI]

    Szymon Pu?awski; for the NA61 Collaboration

    2015-02-27

    The NA61/SHINE experiment at the CERN SPS aims to discover the critical point of strongly interacting matter and study the properties of the onset of deconfinement. In order to reach these goals measurements of hadron production properties are performed in nucleus-nucleus, proton-proton and proton-nucleus interactions as a function of collision energy and size of the colliding nuclei. Inclusive spectra of identified hadrons in p+p interactions at the SPS energies are presented as a function of transverse momentum, transverse mass and rapidity. The results are compared with the world data and theoretical models.

  19. Jefferson Lab - Hadron 2015 Conference

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Hadron2015 Privacy and Security Notice PREX - Credit:NASA LINKS Circular Registration Sign-up for JLab Tour Call for Contributions Program Plenary Parallel Conference Venue Lodging...

  20. Energy Efficiency of large Cryogenic Systems: the LHC Case and Beyond

    E-Print Network [OSTI]

    Claudet, S; Ferlin, G; Lebrun, P; Tavian, L; Wagner, U

    2013-01-01

    Research infrastructures for high-energy and nuclear physics, nuclear fusion and production of high magnetic fields are increasingly based on applied superconductivity and associated cryogenics in their quest for scientific breakthroughs at affordable capital and operation costs, a condition for their acceptance and sustained funding by society. The thermodynamic penalty for operating at low temperature makes energy efficiency a key requirement for their large cryogenic systems, from conceptual design to procurement, construction and operation. Meeting this requirement takes a combined approach on several fronts in parallel: management of heat loads and sizing of cooling duties, distribution of cooling power matching the needs of the superconducting devices, efficient production of refrigeration, optimal control resting on precise instrumentation and diagnostics, as well as a targeted industrial procurement policy. The case of the Large Hadron Collider (LHC) at CERN is presented. Potential improvements for fu...

  1. Search for invisible decays of the Higgs boson produced in association with a hadronically decaying vector boson in pp collisions at ?s = 8 with the ATLAS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.; Barklow, T.

    2015-07-18

    A search for Higgs boson decays to invisible particles is performed using 20.3 fb?¹ of pp collision data at a centre-of-mass energy of 8 TeV recorded by the ATLAS detector at the Large Hadron Collider. The process considered is Higgs boson production in association with a vector boson (V = W or Z) that decays hadronically, resulting in events with two or more jets and large missing transverse momentum. No excess of candidates is observed in the data over the background expectation. The results are used to constrain V H production followed by H decaying to invisible particles for themore »Higgs boson mass range 115 H VH × BR(H ? inv.) varies from 1.6 pb at 115 GeV to 0.13 pb at 300 GeV. Assuming Standard Model production and including the gg ? H contribution as signal, the results also lead to an observed upper limit of 78% at 95% confidence level on the branching ratio of Higgs bosons decays to invisible particles at a mass of 125 GeV.« less

  2. Observation of Exclusive Electron-Positron Production in Hadron-Hadron Collisions

    SciTech Connect (OSTI)

    Abulencia, A.; Adelman, J.; Affolder, T.; Akimoto, T.; Albrow, M.G.; Ambrose, D.; Amerio, S.; Amidei, D.; Anastassov, A.; Anikeev, K.; Annovi, A.

    2006-11-01

    We present the first observation of exclusive e{sup +}e{sup -} production in hadron-hadron collisions, using p{bar p} collision data at {radical}s = 1.96 TeV taken by the Run II Collider Detector at Fermilab, and corresponding to an integrated luminosity of 532 pb{sup -1}. We require the absence of any particle signatures in the detector except for an electron and a positron candidate, each with transverse energy E{sub T} > 5 GeV and pseudorapidity |{eta}| < 2. With these criteria, 16 events are observed compared to a background expectation of 1.9 {+-} 0.3 events. These events are consistent in cross section and properties with the QED process p{bar p} {yields} p + e{sup +}e{sup -} + {bar p} through two-photon exchange. The measured cross section is 1.6{sub -0.3}{sup +0.5}(stat) {+-} 0.3(syst) pb. This agrees with the theoretical prediction of 1.71 {+-} 0.01 pb.

  3. High energy hadron-hadron collisions. Annual progress report

    SciTech Connect (OSTI)

    Chou, T.T.

    1991-12-01

    Results of a study on high energy collision with the geometrical model are summarized in three parts: (1) the elastic hadron-hadron collision, (2) the inelastic hadron-hadron collision, and (3) the e{sup +}e{sup {minus}} annihilation. More recent studies are highlighted below. For elastic scattering, a modified form for the hadronic matter form factor of the proton was proposed which remains to be dipole in form but contains an energy-dependent range parameter. This new expression of the opacity function fits the elastic {bar p}p scattering very well from the ISR to S{bar p}pS energies. Extrapolation of this theory also yielded results in good agreement with the {bar p}p differential cross section measured at the Tevatron. For inelastic hadron-hadron collisions, we have made a systematic investigation of the single-particle momentum spectra in the entire S{bar p}pS energy region. Results are useful for the extrapolation of angular distribution to the higher SSC energies. In e{sup +}e{sup {minus}} annihilation, a detailed analysis of all available experimental multiplicity data from PETRA to LEP energies has been performed. We discovered that the cluster size of emitted hadrons increases steadily with energy and is close to 2 as we predicted.

  4. High energy hadron-hadron collisions. Annual progress report

    SciTech Connect (OSTI)

    Chou, T.T.

    1992-12-31

    Results of a study on high energy collisions with the geometrical model are summarized in three parts: (1) the elastic hadron-hadron collision, (2) the inelastic hadron-hadron collision, and (3) e{sup +}e{sup {minus}} annihilation. For elastic scattering, a modified form for the hadronic matter form factor of the proton was proposed which is still dipole in form but contains an energy--dependent range parameter. This new expression of the opacity function fits the elastic {bar p}p scattering very well from the ISR to S{bar p}pS energies. Extrapolation of this theory also yielded results {bar p}p in good agreement with the {bar p}p differential cross section measured at the Tevatron. For inelastic hadron-hadron collisions, we have made a systematic investigation of the single-particle momentum spectra in the entire S{bar p}pS energy region. Results are useful for the extrapolation of angular distribution to the higher SSC energies. In e{sup +}e{sup {minus}} annihilation, a detailed analysis of all available experimental multiplicity data from PETRA to LEP energies has been performed. The cluster size of emitted hadrons increases gradually with energy. Aside from high-energy collisions, the giant fullerene molecules were studied and precise algebraic eigenvalue expressions of the Hueckel problem for carbon-240 were obtained.

  5. On transverse energy production in hadron collisions

    E-Print Network [OSTI]

    Andrei Leonidov

    2000-05-01

    The transverse energy spectrum in the unit rapidity window in p-bar p collisions at 540 GeV c.m.s energy is calculated to the next-to-leading order accuracy O(a_s^3) and compared to the experimental data by UA(2) collaboration. We show that the calculated spectrum starts matching experimental data only at relatively large transverse energy Et=60 GeV and is in essential disagreement with it both in shape and magnitude at lower transverse energies. The data are well reproduced by HIJING Monte-Carlo generator indicating the crucial importance of all-order effects in perturbation theory as well as those of hadronization in describing the transverse energy production in hadron collisions at small and intermediate transverse energies.

  6. High energy hadron-hadron collisions. Final report

    SciTech Connect (OSTI)

    Chou, T.T.

    1995-08-01

    This project of studying high energy collision phenomena with the geometrical model has been undertaken and developed by this investigator and collaborators since 1967. Instead of basing conjectures on mathematical extrapolations from some ad hoc theories, this approach was to scrutinize first the general features of the phenomena before going into specific details. This particular method has proved successful in correlating experimental data, suggesting experiments, predicting new phenomena and guiding future experimental studies. In the following, important results of the geometrical model obtained with the support of the DOE grant are summarized in three parts: the elastic hadron-hadron scattering, the inelastic hadron-hadron collision, and the hadronic production in e{sup +}e{sup {minus}} annihilation. The fourth part of this report outlines the results of other topics of investigation. To avoid repetition, only the main physical ideas and essential experimental evidences are presented, leaving out detailed discussions which can be found in the literature and previous reports.

  7. Conventional power sources for colliders

    SciTech Connect (OSTI)

    Allen, M.A.

    1987-07-01

    At SLAC we are developing high peak-power klystrons to explore the limits of use of conventional power sources in future linear colliders. In an experimental tube we have achieved 150 MW at 1 ..mu..sec pulse width at 2856 MHz. In production tubes for SLAC Linear Collider (SLC) we routinely achieve 67 MW at 3.5 ..mu..sec pulse width and 180 pps. Over 200 of the klystrons are in routine operation in SLC. An experimental klystron at 8.568 GHz is presently under construction with a design objective of 30 MW at 1 ..mu..sec. A program is starting on the relativistic klystron whose performance will be analyzed in the exploration of the limits of klystrons at very short pulse widths.

  8. A New Hadron Spectroscopy

    E-Print Network [OSTI]

    Stephen Lars Olsen

    2014-11-28

    QCD-motivated models for hadrons predict an assortment of "exotic" hadrons that have structures that are more complex than the quark-antiquark mesons and three-quark baryons of the original quark-parton model. These include pentaquark baryons, the six-quark H-dibaryon, and tetraquark, hybrid and glueball mesons. Despite extensive experimental searches, no unambiguous candidates for any of these exotic configurations have been identified. On the other hand, a number of meson states, one that seems to be a proton-antiproton bound state, and others that contain either charmed-anticharmed quark pairs or bottom-antibottom quark pairs, have been recently discovered that neither fit into the quark-antiquark meson picture nor match the expected properties of the QCD-inspired exotics. Here I briefly review results from a recent search for the H-dibaryon, and discuss some properties of the newly discovered states --the proton-antiproton state and the so-called XYZ mesons-- and compare them with expectations for conventional quark-antiquark mesons and the predicted QCD-exotic states.

  9. Heavy-quark probes of the quark-gluon plasma and interpretation of recent data taken at the BNL Relativistic Heavy Ion Collider 

    E-Print Network [OSTI]

    van Hees, H.; Greco, V.; Rapp, Ralf.

    2006-01-01

    strongly interacting QGP (sQGP), as well as parton coalescence, can play an essential role in the interpretation of recent data from the BNL Relativistic Heavy-Ion Collider (RHIC), and thus illuminate the nature of the sQGP and its hadronization. Our main...

  10. Inclusive Production of {rho}{+-}(770) Meson in Hadronic Decays of Z0 Boson

    SciTech Connect (OSTI)

    Beddall, A.; Beddall, A.; Binguel, A.

    2007-04-23

    The inclusive production of the charged vector meson {rho}{+-}(770) in hadronic Z decays is measured with the ALEPH detector at the LEP collider. Decays of {rho}{+-} {yields} {pi}0 + {pi}{+-} are reconstructed for x > 0.05 where x = E{rho}/Ebeam. The results are compared with Monte Carlo model predictions and OPAL measurements. Bose-Einstein effects are found to be important in extracting {rho}{+-}(770) from two pion invariant mass spectra.

  11. Nuclear physics with a medium-energy Electron-Ion Collider

    E-Print Network [OSTI]

    A. Accardi; V. Guzey; A. Prokudin; C. Weiss

    2011-10-05

    A polarized ep/eA collider (Electron-Ion Collider, or EIC) with variable center-of-mass energy sqrt(s) ~ 20-70 GeV and a luminosity ~ 10^{34} cm^{-2} s^{-1} would be uniquely suited to address several outstanding questions of Quantum Chromodynamics (QCD) and the microscopic structure of hadrons and nuclei: (i) the three-dimensional structure of the nucleon in QCD (sea quark and gluon spatial distributions, orbital motion, polarization, correlations); (ii) the fundamental color fields in nuclei (nuclear parton densities, shadowing, coherence effects, color transparency); (iii) the conversion of color charge to hadrons (fragmentation, parton propagation through matter, in-medium jets). We briefly review the conceptual aspects of these questions and the measurements that would address them, emphasizing the qualitatively new information that could be obtained with the collider. Such a medium-energy EIC could be realized at Jefferson Lab after the 12 GeV Upgrade (MEIC), or at Brookhaven National Lab as the low-energy stage of eRHIC.

  12. Nuclear physics with a medium-energy Electron-Ion Collider

    E-Print Network [OSTI]

    Accardi, A; Prokudin, A; Weiss, C

    2011-01-01

    A polarized ep/eA collider (Electron-Ion Collider, or EIC) with variable center-of-mass energy sqrt(s) ~ 20-70 GeV and a luminosity ~ 10^{34} cm^{-2} s^{-1} would be uniquely suited to address several outstanding questions of Quantum Chromodynamics (QCD) and the microscopic structure of hadrons and nuclei: (i) the three-dimensional structure of the nucleon in QCD (sea quark and gluon spatial distributions, orbital motion, polarization, correlations); (ii) the fundamental color fields in nuclei (nuclear parton densities, shadowing, coherence effects, color transparency); (iii) the conversion of color charge to hadrons (fragmentation, parton propagation through matter, in-medium jets). We briefly review the conceptual aspects of these questions and the measurements that would address them, emphasizing the qualitatively new information that could be obtained with the collider. Such a medium-energy EIC could be realized at Jefferson Lab after the 12 GeV Upgrade (MEIC), or at Brookhaven National Lab as the low-ene...

  13. Collider Phenomenology with Split-UED

    SciTech Connect (OSTI)

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

    2011-12-15

    We investigate the collider implications of Split Universal Extra Dimensions. The non-vanishing fermion mass in the bulk, which is consistent with the KK-parity, largely modifies the phenomenology of Minimal Universal Extra Dimensions. We scrutinize the behavior of couplings and study the discovery reach of the Tevatron and the LHC for level-2 Kaluza-Klein modes in the dilepton channel, which would indicates the presence of the extra dimensions. Observation of large event rates for dilepton resonances can result from a nontrivial fermion mass profile along the extra dimensions, which, in turn, may corroborate extra dimensional explanation for the observation of the positron excess in cosmic rays. The Minimal Universal Extra Dimensions scenario has received great attention. Recently non-vanishing bulk fermion masses have been introduced without spoiling the virtue of KK-parity. The fermion profiles are no longer simple sine/cosine functions and depend upon the specific values of bulk parameters. The profiles of fermions are split along the extra dimensions while the wave functions of the bosons remain the same as in UED. A simple introduction of a KK-parity conserving bulk fermion mass has significant influences on collider aspects as well as astrophysical implications of UED. For instance, the DM annihilation fraction into certain SM fermion pairs is either enhanced or reduced (compared to the MUED case) so that one can perhaps explain the PAMELA positron excess while suppressing the anti-proton flux. In this paper, we have concentrated on collider phenomenology of Split Universal Extra Dimensions. We have revisited the KK decomposition in detail and analyzed wave function overlaps to compute relevant couplings for collider studies. We have discussed general collider implication for level-1 KK modes and level-2 KK with non-zero bulk mass and have computed LHC reach for the EW level-2 KK bosons, {gamma}{sub 2} and Z{sub 2}, in the dilepton channel. The LHC should 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.

  14. Harmonic potential and hadron spectroscopy

    E-Print Network [OSTI]

    Rafael Tumanyan

    2009-05-28

    The quark-gluon sea in the hadrons is considered as periodically correlated. Energy levels of Shrodinger equation with harmonic potential is used for describing of the spectrum of hadron masses. In the considered cases the effective potential operating on each particle of ensemble, under certain conditions becomes square-law on displacement from a equilibrium point. It can become an explanation of popularity of oscillator potential for the description of a spectrum of masses of elementary particles. The analysis shows that levels of periodic potential better agreed to the spectrum of hadron masses, than levels of other potentials used for an explanation of a spectrum of masses.

  15. Detector Background at Muon Colliders

    SciTech Connect (OSTI)

    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.

  16. Tevatron instrumentation: boosting collider performance

    SciTech Connect (OSTI)

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

    2006-05-01

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

  17. Twistor Spinoffs for Collider Physics

    SciTech Connect (OSTI)

    Dixon, Lance

    2005-12-19

    Finding the adding up of Feynman diagrams tedious? Hidden symmetries found in the sums of diagrams suggest there is a better way to predict the results of particle collisions - in the past two years, spin-offs of a new theory, known as the Twistor String Theory, have led to the development of efficient alternatives to Feynman diagrams which can be useful for work at the Tevatron, the LHC and for future research at the International Linear Collider. Come see what this 'twistor' is all about!

  18. Muon Colliders and Neutrino Factories

    E-Print Network [OSTI]

    Daniel M. Kaplan; for the MAP; MICE Collaborations

    2014-12-10

    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.

  19. Chemical properties of super-hadronic matter created in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Scott Pratt; Claudia Ratti; William Patrick McCormack

    2014-09-07

    Preliminary charge balance functions from the STAR Collaboration at the Relativistic Heavy Ion Collider (RHIC) are compared to a model where quarks are produced in two waves. If a chemically equilibrated quark-gluon plasma (QGP) is created the strength and diffusive spread of the first wave should be governed by the chemical composition of the QGP, while the second wave should be determined by the increased number of quarks required to make the observed final-state hadrons. A simple model parameterizes the chemistry of the super-hadronic matter and the two correlation lengths for the two waves. Calculations are compared to preliminary data from the STAR Collaboration. The chemistry of the super-hadronic matter appears to be within 20\\% of expectations from lattice gauge theory.

  20. Quasiparticle Theory of Transport Coefficients for Hadronic Matter at Finite Temperature and Baryon Density

    E-Print Network [OSTI]

    M. Albright; J. I. Kapusta

    2015-08-11

    We develop a flexible quasiparticle theory of transport coefficients of hot hadronic matter at finite baryon density. We begin with a hadronic quasiparticle model which includes a scalar and a vector mean field. Quasiparticle energies and the mean fields depend on temperature and baryon chemical potential. Starting with the quasiparticle dispersion relation, we derive the Boltzmann equation and use the Chapman-Enskog expansion to derive formulas for the shear and bulk viscosities and thermal conductivity. We obtain both relaxation time approximation formulas and more general integral equations. Throughout the work, we explicitly enforce the Landau-Lifshitz conditions of fit and ensure the theory is thermodynamically self-consistent. The derived formulas should be useful for predicting the transport coefficients of the hadronic phase of matter produced in heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) and at other accelerators.

  1. Longitudinal-transverse double-spin asymmetries in single-inclusive leptoproduction of hadrons

    E-Print Network [OSTI]

    K. Kanazawa; A. Metz; D. Pitonyak; M. Schlegel

    2015-02-06

    We analyze the longitudinal-transverse double-spin asymmetry in lepton-nucleon collisions where a single hadron is detected in the final state, i.e., $\\vec{\\ell}\\,N^\\uparrow \\rightarrow h\\,X$. This is a subleading-twist observable in collinear factorization, and we look at twist-3 effects in both the transversely polarized nucleon and the unpolarized outgoing hadron. Results are anticipated for this asymmetry from both HERMES and Jefferson Lab Hall A, and it could be measured as well at COMPASS and a future Electron-Ion Collider. We also perform a numerical study of the distribution term, which, when compared to upcoming experimental results, could allow one to learn about the "worm-gear"-type function $\\tilde{g}(x)$ as well as assess the role of quark-gluon-quark correlations in the initial-state nucleon and twist-3 effects in the fragmenting unpolarized hadron.

  2. International Workshop on Linear Colliders 2010

    ScienceCinema (OSTI)

    None

    2011-10-06

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

  3. Superconducting materials for large scale applications

    SciTech Connect (OSTI)

    Scanlan, Ronald M.; Malozemoff, Alexis P.; Larbalestier, David C.

    2004-05-06

    Significant improvements in the properties ofsuperconducting materials have occurred recently. These improvements arebeing incorporated into the latest generation of wires, cables, and tapesthat are being used in a broad range of prototype devices. These devicesinclude new, high field accelerator and NMR magnets, magnets for fusionpower experiments, motors, generators, and power transmission lines.These prototype magnets are joining a wide array of existing applicationsthat utilize the unique capabilities of superconducting magnets:accelerators such as the Large Hadron Collider, fusion experiments suchas ITER, 930 MHz NMR, and 4 Tesla MRI. In addition, promising newmaterials such as MgB2 have been discovered and are being studied inorder to assess their potential for new applications. In this paper, wewill review the key developments that are leading to these newapplications for superconducting materials. In some cases, the key factoris improved understanding or development of materials with significantlyimproved properties. An example of the former is the development of Nb3Snfor use in high field magnets for accelerators. In other cases, thedevelopment is being driven by the application. The aggressive effort todevelop HTS tapes is being driven primarily by the need for materialsthat can operate at temperatures of 50 K and higher. The implications ofthese two drivers for further developments will be discussed. Finally, wewill discuss the areas where further improvements are needed in order fornew applications to be realized.

  4. International Linear Collider Technical Design Report - Volume...

    Office of Scientific and Technical Information (OSTI)

    Linear Collider Technical Design Report - Volume 2: Physics Baer, Howard; Barklow, Tim; Fujii, Keisuke; Gao, Yuanning; Hoang, Andre; Kanemura, Shinya; List, Jenny; Logan, Heather...

  5. JLab Supports International Linear Collider Cavity Development...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Supports International Linear Collider Cavity Development Work NEWPORT NEWS, Va. Feb. 12, 2008 - It's not often that major-league baseball and nuclear physics get to share the...

  6. Plenary: Photon-Photon and Electron-Photon Colliders Mayda M. Velasco

    E-Print Network [OSTI]

    electron-positron colliders like the Interna- tional Linear Collider (ILC) and/or Compact LInear Collider

  7. Evaluation of measurement accuracies of the Higgs boson branching fractions in the International Linear Collider

    E-Print Network [OSTI]

    H. Ono; A. Miyamoto

    2013-03-19

    Precise measurement of Higgs boson couplings is an important task for International Linear Collider (ILC) experiments and will facilitate the understanding of the particle mass generation mechanism. In this study, the measurement accuracies of the Higgs boson branching fractions to the $b$ and $c$ quarks and gluons, $\\Delta Br(H\\to b\\bar{b},\\sim c\\bar{c},\\sim gg)/Br$, were evaluated with the full International Large Detector model (\\texttt{ILD\\_00}) for the Higgs mass of 120 GeV at the center-of-mass (CM) energies of 250 and 350 GeV using neutrino, hadronic and leptonic channels and assuming an integrated luminosity of $250 {\\rm fb^{-1}}$, and an electron (positron) beam polarization of -80% (+30%). We obtained the following measurement accuracies of the Higgs cross section times branching fraction ($\\Delta (\\sigma \\cdot Br)/\\sigma \\cdot Br$) for decay of the Higgs into $b\\bar{b}$, $c\\bar{c}$, and $gg$; as 1.0%, 6.9%, and 8.5% at a CM energy of 250 GeV and 1.0%, 6.2%, and 7.3% at 350 GeV, respectively. After the measurement accuracy of the cross section ($\\Delta\\sigma/\\sigma$) was corrected using the results of studies at 250 GeV and their extrapolation to 350 GeV, the derived measurement accuracies of the branching fractions ($\\Delta Br/Br$) to $b\\bar{b}$, $c\\bar{c}$, and gg were 2.7%, 7.3%, and 8.9% at a CM energy of 250 GeV and 3.6%, 7.2%, and 8.1% at 350 GeV, respectively.

  8. The Dismantling Project for the Large Electron Positron (LEP) Collider

    E-Print Network [OSTI]

    Poole, John

    2002-01-01

    The LEP accelerator was installed in a circular tunnel 27 km in length with nine access points distributed around the circumference in the countryside and villages which surround CERN's sites. The dismantling project involved the removal in less than 15 months of around 29000 tonnes of equipment from the accelerator itself and a further 10000 tonnes from the four experiments - all of which were located at an average depth of 100 m below ground level. There was no contamination risk in the project and less than 3% of the materials removed were classified as radioactive. However, the materials which were classified as radioactive have to be temporarily stored and they consume considerable resources. The major difficulties for the project were in the establishment of the theoretical radiological zoning, implementation of the traceability systems and making appropriate radiation measurements to confirm the zoning. The absence of detailed guidelines from the French authorities, having no threshold levels for relea...

  9. The Relic Neutralino Surface at a 100 TeV collider

    E-Print Network [OSTI]

    Joseph Bramante; Patrick J. Fox; Adam Martin; Bryan Ostdiek; Tilman Plehn; Torben Schell; Michihisa Takeuchi

    2015-03-27

    We map the parameter space for MSSM 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 TeV hadron collider, which can discover inter-neutralino 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: 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. We exploit this kinematic feature in final states including photons and leptons, tailored to the 100 TeV collider environment.

  10. Transverse momentum dependent gluon fragmentation functions from $J/\\psi\\ \\pi$ production at $e^+ e^-$ colliders

    E-Print Network [OSTI]

    Zhang, Guang-Peng

    2015-01-01

    The back-to-back $J/\\psi$ and $\\pi$ associated production at $e^+ e^-$ colliders is proposed to detect the gluon transverse momentum dependent(TMD) fragmentation functions. TMD factorization is assumed for this process. With spinless pion, unpolarized and linearly polarized gluon TMD fragmentation functions can be defined. It is found at parton level the hadronic tensor can be described by four structure functions. As a result, there are three independent angular distributions, of which a $\\cos{2\\phi}$ azimuthal asymmetry is sensitive to the linearly polarized gluon fragmentation function.

  11. Search for charged Higgs bosons decaying via H ± ? ?± ? in fully hadronic final states using pp collision data at ?s = 8 TeV with the ATLAS detector

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Aad, G.

    2015-03-17

    The results of a search for charged Higgs bosons decaying to a ? lepton and a neutrino, H ± ? ?± ?, are presented. The analysis is based on 19.5 fb–1 of proton-proton collision data at ?s = 8 TeV collected by the ATLAS experiment at the Large Hadron Collider. Charged Higgs bosons are searched for in events consistent with top-quark pair production or in associated production with a top quark, depending on the considered H± mass. The final state is characterized by the presence of a hadronic ? decay, missing transverse momentum, b-tagged jets, a hadronically decaying W boson,more »and the absence of any isolated electrons or muons with high transverse momenta. The data are consistent with the expected background from Standard Model processes. A statistical analysis leads to 95% confidence-level upper limits on the product of branching ratios ?(t ? bH±) × ?(H± ? ?± ?), between 0.23% and 1.3% for charged Higgs boson masses in the range 80-160GeV. It also leads to 95% confidence-level upper limits on the production cross section times branching ratio, ?(pp ? tH±+ X) × ?(H± ? ?± ?), between 0.76 pb and 4.5 fb, for charged Higgs boson masses ranging from 180 GeV to 1000 GeV. In the context of different scenarios of the Minimal Supersymmetric Standard Model, these results exclude nearly all values of tan ? above one for charged Higgs boson masses between 80 GeV and 160 GeV, and exclude a region of parameter space with high tan ? for H± masses between 200 GeV and 250 GeV.« less

  12. Probing Universal Extra Dimension at the International Linear Collider

    E-Print Network [OSTI]

    Gautam Bhattacharyya; Paramita Dey; Anirban Kundu; Amitava Raychaudhuri

    2005-09-02

    In the context of an universal extra-dimensional scenario, we consider production of the first Kaluza-Klein electron positron pair in an $e^+e^-$ collider as a case-study for the future International Linear Collider. The Kaluza-Klein electron decays into a nearly degenerate Kaluza-Klein photon and a standard electron, the former carrying away missing energy. The Kaluza-Klein electron and photon states are heavy with their masses around the inverse radius of compactification, and their splitting is controlled by radiative corrections originating from bulk and brane-localised interactions. We look for the signal event $e^+e^- +$ large missing energy for $\\sqrt s = 1$ TeV and observe that with a few hundred fb$^{-1}$ luminosity the signal will be readily detectable over the standard model background. We comment on how this signal may be distinguished from similar events from other new physics.

  13. Status of superconducting magnets for the Superconducting Super Collider

    SciTech Connect (OSTI)

    Schermer, R.I.

    1993-09-01

    The arc sections of the High Energy Booster and the two Collider Rings will need more than 10,000, very large, superconducting dipole and quadrupole magnets. Development work on these magnets was carried out at US/DOE laboratories in a program that began in the mid 1980`s. In 1991-1992, the technology was transferred to industry and twenty, full-length, Collider dipoles were successfully fabricated and tested. This program, along with HERA and Tevatron experience, has provided industry a data base to use in formulating detailed designs for the prototypes of the accelerator magnets, with an eye to reducing cost and enhancing producibility. Several model magnets from this latest phase of the industrial program have already been tested. The excessive ramp-rate sensitivity of the magnets is understood and solutions are under investigation.

  14. Search for SUSY at LHC: Precision Measurements

    E-Print Network [OSTI]

    Frank E. Paige

    1997-12-16

    Methods to make precision measurements of SUSY masses and parameters at the CERN Large Hadron Collider are described.

  15. Properties of a Moscow Glass Gas Microstrip Chamber

    E-Print Network [OSTI]

    and excellent position resolution that make it a rele­ vant technology for tracking at the Large Hadron Collider

  16. Hadron particle theory

    SciTech Connect (OSTI)

    Alonso, J.R.

    1995-05-01

    Radiation therapy with ``hadrons`` (protons, neutrons, pions, ions) has accrued a 55-year track record, with by now over 30,000 patients having received treatments with one of these particles. Very good, and in some cases spectacular results are leading to growth in the field in specific well-defined directions. The most noted contributor to success has been the ability to better define and control the radiation field produced with these particles, to increase the dose delivered to the treatment volume while achieving a high degree of sparing of normal tissue. An additional benefit is the highly-ionizing, character of certain beams, leading to creater cell-killing potential for tumor lines that have historically been very resistant to radiation treatments. Until recently these treatments have been delivered in laboratories and research centers whose primary, or original mission was physics research. With maturity in the field has come both the desire to provide beam facilities more accessible to the clinical setting, of a hospital, as well as achieving, highly-efficient, reliable and economical accelerator and beam-delivery systems that can make maximum advantage of the physical characteristics of these particle beams. Considerable work in technology development is now leading, to the implementation of many of these ideas, and a new generation of clinically-oriented facilities is beginning to appear. We will discuss both the physical, clinical and technological considerations that are driving these designs, as well as highlighting, specific examples of new facilities that are either now treating, patients or that will be doing so in the near future.

  17. Deep Inelastic Scattering from Holographic Spin-One Hadrons

    E-Print Network [OSTI]

    Ezequiel Koile; Sebastian Macaluso; Martin Schvellinger

    2011-12-30

    We study deep inelastic scattering structure functions from hadrons using different holographic dual models which describe the strongly coupled regime of gauge theories in the large $N$ limit. Particularly, we consider scalar and vector mesons obtained from holographic descriptions with fundamental degrees of freedom, corresponding to ${\\cal {N}}=2$ supersymmetric and non-supersymmetric Yang-Mills theories. We explicitly obtain analytic expressions for the full set of eight structure functions, i.e., $F_1$, $F_2$, $g_1$, $g_2$, $b_1$, $b_2$, $b_3$, $b_4$, arising from the standard decomposition of the hadronic tensor of spin-one hadrons. We obtain the relations $2 F_1 = F_2$ and $2 b_1 = b_2$. In addition, we find $b_1 \\sim {\\cal {O}}(F_1)$ as suggested by Hoodbhoy, Jaffe and Manohar for vector mesons. Also, we find new relations among some of these structure functions.

  18. Updates to the International Linear Collider Damping Rings Baseline...

    Office of Scientific and Technical Information (OSTI)

    Updates to the International Linear Collider Damping Rings Baseline Design Citation Details In-Document Search Title: Updates to the International Linear Collider Damping Rings...

  19. BRAHMS (Broad Range Hadron Magnetic Spectrometer) Figures and Data Archive

    DOE Data Explorer [Office of Scientific and Technical Information (OSTI)]

    The BRAHMS experiment was designed to measure charged hadrons over a wide range of rapidity and transverse momentum to study the reaction mechanisms of the relativistic heavy ion reactions at the Relativistic Heavy Ion Collider at Brookhaven National Laboratory and the properties of the highly excited nuclear matter formed in these reactions. The experiment took its first data during the RHIC 2000 year run and completed data taking in June 2006. The BRAHMS archive makes publications available and also makes data and figures from those publications available as separate items. See also the complete list of publications, multimedia presentations, and related papers at http://www4.rcf.bnl.gov/brahms/WWW/publications.html

  20. A High-Energy High-Luminosity p+-p* Collider David V. Neuffer, CEBAF', 12000 Jefferson Avenue, Newport News VA 23692

    E-Print Network [OSTI]

    McDonald, Kirk

    accepta large energy pizq Figure 1. A p+-p' Collider System. *Researchsupportedby DOEcontract#DE-AC05-84ER40150. 52 #12;width (2*1 GeV) and have a large transverse acceptance(p,

  1. Near-threshold production of $W^\\pm$, $Z^0$ and $H^0$ at a fixed-target experiment at the future ultra-high-energy proton colliders

    E-Print Network [OSTI]

    J. P. Lansberg; R. E. Mikkelsen; U. I Uggerhøj

    2015-08-18

    We outline the opportunities to study the production of the Standard Model bosons, $W^\\pm$, $Z^0$ and $H^0$ at "low" energies at fixed-target experiments based at possible future ultra-high-energy proton colliders, \\ie\\ the High-Energy LHC, the Super proton-proton Collider and the Future Circular Collider -- hadron-hadron. These can be indeed made in conjunction with the proposed future colliders designed to reach up to $\\sqrt{s}=100$ TeV by using bent crystals to extract part of the halo of the beam which would then impinge on a fixed target. Without disturbing the collider operation, this technique allows for the extraction of a substantial amount of particles in addition to serve for a beam-cleaning purpose. With this method, high-luminosity fixed-target studies at centre-of-mass energies above the $W^\\pm$, $Z^0$ and $H^0$ masses, $\\sqrt{s} \\simeq 170-300$ GeV, are possible. We also discuss the possibility offered by an internal gas target, which can also be used as luminosity monitor by studying the beam transverse shape.

  2. Near-threshold production of $W^\\pm$, $Z^0$ and $H^0$ at a fixed-target experiment at the future ultra-high-energy proton colliders

    E-Print Network [OSTI]

    Lansberg, J P; Uggerhøj, U I

    2015-01-01

    We outline the opportunities to study the production of the Standard Model bosons, $W^\\pm$, $Z^0$ and $H^0$ at "low" energies at fixed-target experiments based at possible future ultra-high-energy proton colliders, \\ie\\ the High-Energy LHC, the Super proton-proton Collider and the Future Circular Collider -- hadron-hadron. These can be indeed made in conjunction with the proposed future colliders designed to reach up to $\\sqrt{s}=100$ TeV by using bent crystals to extract part of the halo of the beam which would then impinge on a fixed target. Without disturbing the collider operation, this technique allows for the extraction of a substantial amount of particles in addition to serve for a beam-cleaning purpose. With this method, high-luminosity fixed-target studies at centre-of-mass energies above the $W^\\pm$, $Z^0$ and $H^0$ masses, $\\sqrt{s} \\simeq 170-300$ GeV, are possible. We also discuss the possibility offered by an internal gas target, which can also be used as luminosity monitor by studying the beam ...

  3. VNI version 4.1. Simulation of high-energy particle collisions in QCD: Space-time evolution of e{sup +}e{sup {minus}}...A + B collisions with parton-cascades, cluster-hadronization, final-state hadron cascades

    SciTech Connect (OSTI)

    Geiger, K.; Longacre, R.; Srivastava, D.K.

    1999-02-01

    VNI is a general-purpose Monte-Carlo event-generator, which includes the simulation of lepton-lepton, lepton-hadron, lepton-nucleus, hadron-hadron, hadron-nucleus, and nucleus-nucleus collisions. It uses the real-time evolution of parton cascades in conjunction with a self-consistent hadronization scheme, as well as the development of hadron cascades after hadronization. The causal evolution from a specific initial state (determined by the colliding beam particles) is followed by the time-development of the phase-space densities of partons, pre-hadronic parton clusters, and final-state hadrons, in position-space, momentum-space and color-space. The parton-evolution is described in terms of a space-time generalization of the familiar momentum-space description of multiple (semi)hard interactions in QCD, involving 2 {r_arrow} 2 parton collisions, 2 {r_arrow} 1 parton fusion processes, and 1 {r_arrow} 2 radiation processes. The formation of color-singlet pre-hadronic clusters and their decays into hadrons, on the other hand, is treated by using a spatial criterion motivated by confinement and a non-perturbative model for hadronization. Finally, the cascading of produced prehadronic clusters and of hadrons includes a multitude of 2 {r_arrow} n processes, and is modeled in parallel to the parton cascade description. This paper gives a brief review of the physics underlying VNI, as well as a detailed description of the program itself. The latter program description emphasizes easy-to-use pragmatism and explains how to use the program (including simple examples), annotates input and control parameters, and discusses output data provided by it.

  4. Charmonium absorption and charmed hadron production in hadronic reactions 

    E-Print Network [OSTI]

    Liu, Wei

    2005-02-17

    factor to the measured total cross section for charmed hadron production in photon-proton reactions at a center-of-mass energy of 6 GeV, the ratio of the cross sections for two-body and three-body ?nal states is consistent with available...

  5. Jets from Jets: Re-clustering as a tool for large radius jet reconstruction and grooming at the LHC

    E-Print Network [OSTI]

    Benjamin Nachman; Pascal Nef; Ariel Schwartzman; Maximilian Swiatlowski; Chaowaroj Wanotayaroj

    2014-12-11

    Jets with a large radius $R\\gtrsim 1$ and grooming algorithms are widely used to fully capture the decay products of boosted heavy particles at the Large Hadron Collider (LHC). Unlike most discriminating variables used in such studies, the jet radius is usually not optimized for specific physics scenarios. This is because every jet configuration must be calibrated, insitu, to account for detector response and other experimental effects. One solution to enhance the availability of large-$R$ jet configurations used by the LHC experiments is {\\it jet re-clustering}. Jet re-clustering introduces an intermediate scale $rjets are calibrated and used as the inputs to reconstruct large radius jets. In this paper we systematically study and propose new jet re-clustering configurations and show that re-clustered large radius jets have essentially the same jet mass performance as large radius groomed jets. Jet re-clustering has the benefit that no additional large-R calibration is necessary, allowing the re-clustered large radius parameter to be optimized in the context of specific precision measurements or searches for new physics.

  6. Vertex Detection for a Charm Tag in e+e- -> W+W- at a High Energy Electron-Positron Linear Collider

    E-Print Network [OSTI]

    Wolfgang Walkowiak

    2001-10-18

    The study of the process $e^+e^- \\to W^+W^-$ at Linear Collider energies presents a good opportunity to investigate anomalous triple gauge boson couplings and $W^+_LW^-_L$ rescattering. The helicity analysis of the $e^+e^- \\to W^+_LW^-_L$ decays will benefit if the charm quark containing jet can be identified for events which contain one hadronic $W$ boson decay to a charm and another quark. A JAVA implementation of the SLD collaboration's topological vertex finding algorithm (ZVTOP) in the linear collider analysis framework has been used to extract charm tag efficiencies and purities based on vertex multiplicities.

  7. Exploring top quark FCNC at hadron colliders in association with flavor physics

    E-Print Network [OSTI]

    Kim, C S; Yuan, Xing-Bo

    2015-01-01

    The top quark flavor changing neutral current (FCNC) process is an excellent probe to search for new physics in top sector since the Standard Model expectation is extremely suppressed. We explore Higgs-mediated top quark FCNC, focusing on H-t-c Yukawa coupling \\lambda_{ct} within the general two Higgs doublet model. After electroweak symmetry breaking the top quark FCNC couplings are included in the charged Higgs Yukawa sector so that they contribute to various processes in flavor physics. To probe \\lambda_{ct}, we study anomalous single top production and the same sign top pair production at the LHC in association with flavor physics from the tree-level processes B \\to D^{(*)} \\tau \

  8. Neural Networks Search for Charged Higgs Boson of Two Doublet Higgs Model at the Hadrons Colliders

    E-Print Network [OSTI]

    Bakhet, Nady; Hussein, Tarek

    2015-01-01

    In this work, we present an analysis of a search for charged Higgs boson in the context of Two Doublet Higgs Model (2HDM) which is an extension of the Standard Model of particles physics. The 2HDM predicts by existence scalar sector with new five Higgs bosons, two of them are electrically charged and the other three Higgs bosons are neutral charged. Our analysis based on the Monte Carlo data produced from the simulation of 2HDM with proton antiproton collisions at the Tevatron $\\sqrt{s}=1.96$ TeV (Fermi Lab) and proton proton collisions at the LHC $\\sqrt{s}=14$ TeV (CERN) with final state includes electron , muon , multiple jets and missing transverse energy via the production and decay of the new Higgs in the hard process $pp(\\bar{p})\\rightarrow t\\bar{t}\\rightarrow H^{+}b H^{-}\\bar{b}$

  9. Neural Networks Search for Charged Higgs Boson of Two Doublet Higgs Model at the Hadrons Colliders

    E-Print Network [OSTI]

    Nady Bakhet; Maxim Yu. Khlopov; Tarek Hussein

    2015-07-23

    In this work, we present an analysis of a search for charged Higgs boson in the context of Two Doublet Higgs Model (2HDM) which is an extension of the Standard Model of particles physics. The 2HDM predicts by existence scalar sector with new five Higgs bosons, two of them are electrically charged and the other three Higgs bosons are neutral charged. Our analysis based on the Monte Carlo data produced from the simulation of 2HDM with proton antiproton collisions at the Tevatron $\\sqrt{s}=1.96$ TeV (Fermi Lab) and proton proton collisions at the LHC $\\sqrt{s}=14$ TeV (CERN) with final state includes electron , muon , multiple jets and missing transverse energy via the production and decay of the new Higgs in the hard process $pp(\\bar{p})\\rightarrow t\\bar{t}\\rightarrow H^{+}b H^{-}\\bar{b}$

  10. Lepton number violating processes mediated by Majorana neutrinos at hadron colliders

    SciTech Connect (OSTI)

    Kovalenko, Sergey; Lu Zhun; Schmidt, Ivan [Departamento de Fisica, Universidad Tecnica Federico, Santa Maria, Casilla 110-V, Valparaiso (Chile) and Center of Subatomic Physics, Valparaiso (Chile)

    2009-10-01

    We study the lepton number violating like-sign dilepton processes h{sub 1}h{sub 2}{yields}l{sup {+-}}l{sup '{+-}}jjX and h{sub 1}h{sub 2}{yields}l{sup {+-}}l{sup '{+-}}W{sup {+-}}X, mediated by heavy GeV scale Majorana neutrinos. We focus on the resonantly enhanced contributions with a nearly on-mass-shell Majorana neutrino in the s channel. We study the constraints on like-sign dilepton production at the Tevatron and the LHC on the basis of the existing experimental limits on the masses of heavy neutrinos and their mixings U{sub {alpha}}{sub N} with {alpha}={nu}{sub e}, {nu}{sub {mu}}, {nu}{sub {tau}}. Special attention is paid to the constraints from neutrinoless double beta decay. We note that searches for like-sign e{sup {+-}}e{sup {+-}} events at Tevatron and LHC may provide evidence of CP violation in the neutrino sector. We also discuss the conditions under which it is possible to extract individual constraints on the mixing matrix elements in a model independent way.

  11. Indications of Conical Emission of Charged Hadrons at the BNL Relativistic Heavy Ion Collider

    E-Print Network [OSTI]

    Walker, M.

    Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d+Au, and Au+Au collisions at ?s[subscript NN]=200??GeV by the STAR experiment. Dijet structures are ...

  12. Jet vetoes for Higgs boson production at future hadron colliders (Journal

    Office of Scientific and Technical Information (OSTI)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantity of NaturalDukeWakefieldSulfate Reducing(Journalspectroscopy of aerosols in(JournalTechnical Report:

  13. Future Colliders Beyond the Standard Model

    E-Print Network [OSTI]

    Murayama, Hitoshi

    17 Future Colliders Beyond the Standard Model By the early 1980s there were persuasive arguments the default future of international high energy physics. The LHC project calls for two multipurpose detectors

  14. Colliding cascades model for earthquake prediction

    E-Print Network [OSTI]

    2000-10-12

    on a direct cascade that would deliver energy from the largest size scales ... The general objective of the colliding cascades model has been to reproduce the ..... earthquake and critical phase transitions studied in statistical physics, where the

  15. Structure and Dynamics of Colliding Plasma Jets

    E-Print Network [OSTI]

    Ryutov, D.

    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 ...

  16. Study of gamma gamma Background in e+e- -> W+W- nu nu -> H nu nu Events at the Tesla e+e- Linear Collider

    E-Print Network [OSTI]

    Marco Battaglia; Daniel Schulte

    2000-11-27

    The effect of the overlap of gamma gamma -> hadrons to H nu nu events has been studied for the case of the Tesla e+e- linear collider at 350 GeV. It was found that, due to the significant bunch length and the track extrapolation accuracy provided by the Vertex Tracker, the gamma gamma background to physics events can be substantially reduced, with moderate loss in reconstruction efficiency, by a combination of kinematical and vertex topology observables. The remaining background, being confined to very forward hadron production, does not significantly interfere with the event reconstruction.

  17. Hadronic rescattering effects on multi-strange hadrons in high-energy nuclear collisions

    E-Print Network [OSTI]

    Takeuchi, Shiori; Hirano, Tetsufumi; Huovinen, Pasi; Nara, Yasushi

    2015-01-01

    We study the effects of hadronic rescattering on hadron distributions in high-energy nuclear collisions by using an integrated dynamical approach. This approach is based on a hybrid model combining (3+1)-dimensional ideal hydrodynamics for the quark gluon plasma (QGP), and a transport model for the hadron resonance gas. Since the hadron distributions are the result of the entire expansion history of the system, understanding the QGP properties requires investigating how rescattering during the hadronic stage affects the final distributions of hadrons. We include multi-strange hadrons in our study, and quantify the effects of hadronic rescattering on their mean transverse momenta and elliptic flow. We find that multi-strange hadrons scatter less during the hadronic stage than non-strange particles, and thus their distributions reflect the properties of the system in an earlier stage than the distributions of non-strange particles.

  18. Measurement of top anti-top cross section in proton - anti-proton collider at s**(1/2) = 1.96-TeV

    SciTech Connect (OSTI)

    Mal, Prolay Kumar

    2005-04-01

    Discovery of the top quark in 1995 at the Fermilab Tevatron collider concluded a long search following the 1977 discovery of bottom (b) quark [1] and represents another triumph of the Standard Model (SM) of elementary particles. Top quark is one of the fundamental fermions in the Standard Model of electroweak interactions and is the weak-isospin partner of the bottom quark. A precise measurement of top pair production cross-section would be a test of Quantum Chromodynamics (QCD) prediction. Presently, Tevatron is the world's highest energy collider where protons (p) and anti-protons ({anti p}) collide at a centre of mass energy (ps) of 1.96 TeV. At Tevatron top (t) and anti-top ({anti t}) quarks are predominantly pair produced through strong interactions--quark annihilation ({approx_equal} 85%) and gluon fusion ({approx_equal} 15%). Due to the large mass of top quark, t or {anti t} decays ({approx} 10{sup -25} sec) before hadronization and in SM framework, it decays to a W boson and a b quark with {approx} 100% branching ratio (BR). The subsequent decay of W boson determines the major signatures of t{anti t} decay. If both W bosons (coming from t and {anti t} decays) decay into leptons (viz., ev{sub e}, {mu}{nu}{sub {mu}} or {tau}{nu}{sub {tau}}) the corresponding t{bar t} decay is called dileptonic decay. Of all dileptonic decay modes of t{bar t}, the t{bar t} {yields} WWb{anti b} {yields} ev{sub e}{mu}{nu}{sub {mu}}b{anti b} (e{mu} channel) decay mode has the smallest background contamination from Z{sup 0} production or Drell-Yan process; simultaneously, it has the highest BR ({approx} 3.16%) [2] amongst all dileptonic decay modes of t{bar t}. During Run I (1992-1996) of Tevatron, three e{mu} candidate events were detected by D0 experiment, out of 80 candidate events (inclusive of all decay modes of t{bar t}). Due to the rarity of the t{bar t} events, the measured cross-section has large uncertainty in its value (viz., 5.69 {+-} 1.21(stat) {+-} 1.04(sys) pb {at} {radical}s = 1.8 TeV measured by D0 [3]). This analysis presents a cross section measurement in e{mu} channel utilizing {approx} 228 pb{sup -1} of data collected by D0 experiment during Tevatron Run II (between June 2002 and April 2004).

  19. Photon Linear Collider Gamma-Gamma Summary

    SciTech Connect (OSTI)

    Gronberg, J

    2012-02-27

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

  20. Hadronic interactions and nuclear physics

    E-Print Network [OSTI]

    Silas R. Beane

    2008-12-05

    I give an overview of efforts in the last year to calculate interactions among hadrons using lattice QCD. Results discussed include the extraction of low-energy phase shifts and three-body interactions, and the study of pion and kaon condensation. A critical appraisal is offered of recent attempts to calculate nucleon-nucleon and nucleon-hyperon potentials on the lattice.

  1. Introduction to Hadronic B Physics

    E-Print Network [OSTI]

    Adam F. Falk

    1998-12-01

    An overview of the theory of B physics is given, with an emphasis on issues in the strong interactions and hadronic physics. This article is taken from an introductory chapter of The BaBar Physics Book - Physics at an Asymmetric B Factory, SLAC Report SLAC-R-504. It is written at the level of a basic survey aimed at the experimental community.

  2. Spin splittings among charmed hadrons

    E-Print Network [OSTI]

    Randy Lewis; Nilmani Mathur; R. M. Woloshyn

    2001-09-19

    The mass differences between spin-1/2 and spin-3/2 baryons are compared to the mass differences between spin-0 and spin-1 mesons. Results of simulations for charmed hadrons in the quenched approximation from a tadpole-improved anisotropic action are discussed in the context of other lattice calculations, quark model predictions, heavy quark symmetry predictions and experimental data.

  3. Recent SuperB Design Choices Improve Next-Generation e e___ B-Factory Collider

    SciTech Connect (OSTI)

    Wittmer, W.; Bertsche, K.; Chao, A.; Novokhatski, A.; Nosochkov, Y.; Seeman, J.; Sullivan, M.K.; Wienands, U.; Bogomyagkov, A.V.; Levichev, E.; Nikitin, S.; Piminov, P.; Shatilov, D.; Sinyatkin, S.; Vobly, P.; Okunev, I.N.; Bolzon, B.; Brunetti, L.; Jeremie, A.; Biagini, M.E.; Boni, R.; /Frascati /INFN, Pisa /Pisa U. /INFN, Genoa /Genoa U. /CERN /Orsay, LAL /Saclay

    2011-08-19

    The SuperB international team continues to optimize the design of an electron-positron collider, which will allow the enhanced study of the origins of flavor physics. The project combines the best features of a linear collider (high single-collision luminosity) and a storage-ring collider (high repetition rate), bringing together all accelerator physics aspects to make a very high luminosity of 10{sup 36} cm{sup -2} sec{sup -1}. This asymmetric-energy collider with a polarized electron beam will produce hundreds of millions of B-mesons at the {Upsilon}(4S) resonance. The present design is based on extremely low emittance beams colliding at a large Piwinski angle to allow very low {beta}*{sub y} without the need for ultra short bunches. Use of crab-waist sextupoles will enhance the luminosity, suppressing dangerous resonances and allowing for a higher beam-beam parameter. The project has flexible beam parameters, improved dynamic aperture, and spin-rotators in the Low Energy Ring for longitudinal polarization of the electron beam at the Interaction Point. Optimized for best colliding-beam performance, the facility may also provide high-brightness photon beams for synchrotron radiation applications.

  4. A RECIPE FOR LINEAR COLLIDER FINAL FOCUS SYSTEM DESIGN

    SciTech Connect (OSTI)

    Seryi, Andrei

    2003-05-27

    The design of Final Focus systems for linear colliders is challenging because of the large demagnifications needed to produce nanometer-sized beams at the interaction point. Simple first- and second-order matrix matching have proven insufficient for this task, and minimization of third- and higher-order aberrations is essential. An appropriate strategy is required for the latter to be successful. A recipe for Final Focus design, and a set of computational tools used to implement this approach, are described herein. An example of the use of this procedure is given.

  5. Control Surveys for Underground Construction of the Superconducting Super Collider

    SciTech Connect (OSTI)

    Greening, W.J.Trevor; Robinson, Gregory L.; Robbins, Jeffrey S.; Ruland, Robert E.; /SLAC

    2005-08-16

    Particular care had to be taken in the design and implementation of the geodetic control systems for the Superconducting Super Collider (SSC) due to stringent accuracy requirements, the demanding tunneling schedule, long duration and large size of the construction effort of the project. The surveying requirements and the design and implementation of the surface and underground control scheme for the precise location of facilities which include approximately 120 km of bored tunnel are discussed. The methodology used for the densification of the surface control networks, the technique used for the transfer of horizontal and vertical control into the underground facilities, and the control traverse scheme employed in the tunnels is described.

  6. Heat leak performance of SSC collider dipole magnets

    SciTech Connect (OSTI)

    Weisend, J.G. II; Levin, M.; Franks, D.; Pletzer, R.; Augustynowicz, S.; McInturff, A.D.; Boroski, W.B.

    1993-09-01

    The large number of superconducting dipoles in the SSC results in a stringent heat leak budget for each dipole. Ensuring that the dipoles meet this budget is vital to the successful operation or the collider. This work surveys heat leak measurements taken during 4 different magnet string tests. These tests involved both 40 mm and SO mm aperture dipoles. In these experiments the heat leak to the 80 K shield, 20 K shield and cold mass are measured. The results are compared to predictions from a computational thermal model of the dipole cryostat. Discrepancies are seen between the predicted and measured values. Possible explanations for these discrepancies are given.

  7. A tevatron collider beauty factory. [Final report, 1980--1992

    SciTech Connect (OSTI)

    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.

  8. The fate of long-lived superparticles with hadronic decays after LHC Run 1

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Liu, Zhen; Tweedie, Brock

    2015-06-08

    Supersymmetry searches at the LHC are both highly varied and highly constraining, but the vast majority are focused on cases where the final-stage visible decays are prompt. Scenarios featuring superparticles with detector-scale lifetimes have therefore remained a tantalizing possibility for sub-TeV SUSY, since explicit limits are relatively sparse. Nonetheless, the extremely low backgrounds of the few existing searches for collider-stable and displaced new particles facilitates recastings into powerful long-lived superparticle searches, even for models for which those searches are highly non-optimized. In this paper, we assess the status of such models in the context of baryonic R-parity violation, gauge mediation,more »and mini-split SUSY. We explore a number of common simplified spectra where hadronic decays can be important, employing recasts of LHC searches that utilize different detector systems and final-state objects. The LSP/NLSP possibilities considered here include generic colored superparticles such as the gluino and light-flavor squarks, as well as the lighter stop and the quasi-degenerate Higgsino multiplet motivated by naturalness. We find that complementary coverage over large swaths of mass and lifetime is achievable by superimposing limits, particularly from CMS’s tracker-based displaced dijet search and heavy stable charged particle searches. Adding in prompt searches, we find many cases where a range of sparticle masses is now excluded from zero lifetime to infinite lifetime with no gaps. In other cases, the displaced searches furnish the only extant limits at any lifetime.« less

  9. eRHIC Design Study: An Electron-Ion Collider at BNL

    E-Print Network [OSTI]

    E. C. Aschenauer; M. D. Baker; A. Bazilevsky; K. Boyle; S. Belomestnykh; I. Ben-Zvi; S. Brooks; C. Brutus; T. Burton; S. Fazio; A. Fedotov; D. Gassner; Y. Hao; Y. Jing; D. Kayran; A. Kiselev; M. A. C. Lamont; J. -H. Lee; V. N. Litvinenko; C. Liu; T. Ludlam; G. Mahler; G. McIntyre; W. Meng; F. Meot; T. Miller; M. Minty; B. Parker; R. Petti; I. Pinayev; V. Ptitsyn; T. Roser; M. Stratmann; E. Sichtermann; J. Skaritka; O. Tchoubar; P. Thieberger; T. Toll; D. Trbojevic; N. Tsoupas; J. Tuozzolo; T. Ullrich; E. Wang; G. Wang; Q. Wu; W. Xu; L. Zheng

    2014-12-18

    This document presents BNL's plan for an electron-ion collider, eRHIC, a major new research tool that builds on the existing RHIC facility to advance the long-term vision for Nuclear Physics to discover and understand the emergent phenomena of Quantum Chromodynamics (QCD), the fundamental theory of the strong interaction that binds the atomic nucleus. We describe the scientific requirements for such a facility, following up on the community-wide 2012 white paper, 'Electron-Ion Collider: the Next QCD Frontier', and present a design concept that incorporates new, innovative accelerator techniques to provide a cost-effective upgrade of RHIC with polarized electron beams colliding with the full array of RHIC hadron beams. The new facility will deliver electron-nucleon luminosity of 10^33-10^34 cm-1sec-1 for collisions of 15.9 GeV polarized electrons on either 250 GeV polarized protons or 100 GeV/u heavy ion beams. The facility will also be capable of providing an electron beam energy of 21.2 GeV, at reduced luminosity. We discuss the on-going R&D effort to realize the project, and present key detector requirements and design ideas for an experimental program capable of making the 'golden measurements' called for in the EIC White Paper.

  10. eRHIC Design Study: An Electron-Ion Collider at BNL

    E-Print Network [OSTI]

    Aschenauer, E C; Bazilevsky, A; Boyle, K; Belomestnykh, S; Ben-Zvi, I; Brooks, S; Brutus, C; Burton, T; Fazio, S; Fedotov, A; Gassner, D; Hao, Y; Jing, Y; Kayran, D; Kiselev, A; Lamont, M A C; Lee, J -H; Litvinenko, V N; Liu, C; Ludlam, T; Mahler, G; McIntyre, G; Meng, W; Meot, F; Miller, T; Minty, M; Parker, B; Pinayev, I; Ptitsyn, V; Roser, T; Stratmann, M; Sichtermann, E; Skaritka, J; Tchoubar, O; Thieberger, P; Toll, T; Trbojevic, D; Tsoupas, N; Tuozzolo, J; Ullrich, T; Wang, E; Wang, G; Wu, Q; Xu, W; Zheng, L

    2014-01-01

    This document presents BNL's plan for an electron-ion collider, eRHIC, a major new research tool that builds on the existing RHIC facility to advance the long-term vision for Nuclear Physics to discover and understand the emergent phenomena of Quantum Chromodynamics (QCD), the fundamental theory of the strong interaction that binds the atomic nucleus. We describe the scientific requirements for such a facility, following up on the community wide 2012 white paper, "Electron-Ion Collider: the Next QCD Frontier", and present a design concept that incorporates new, innovative accelerator techniques to provide a cost-effective upgrade of RHIC with polarized electron beams colliding with the full array of RHIC hadron beams. The new facility will deliver electron-nucleon luminosity of $\\sim10^{33} cm^{-2}sec^{-1}$ for collisions of 15.9 GeV polarized electrons on either 250 GeV polarized protons or 100 GeV/u heavy ion beams. The facility will also be capable of providing an electron beam energy of 21.2 GeV, at reduc...

  11. A stochastic method for computing hadronic matrix elements

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Alexandrou, Constantia; Constantinou, Martha; Dinter, Simon; Drach, Vincent; Jansen, Karl; Hadjiyiannakou, Kyriakos; Renner, Dru B.

    2014-01-24

    In this study, we present a stochastic method for the calculation of baryon 3-point functions which is an alternative to the typically used sequential method offering more versatility. We analyze the scaling of the error of the stochastically evaluated 3-point function with the lattice volume and find a favorable signal to noise ratio suggesting that the stochastic method can be extended to large volumes providing an efficient approach to compute hadronic matrix elements and form factors.

  12. Gluon saturation and pseudo-rapidity distributions of charged hadrons at RHIC energy regions

    E-Print Network [OSTI]

    Xin-Bin Wei; Sheng-Qin Feng

    2014-11-20

    We modified the gluon saturation model by rescaling the momentum fraction according to saturation momentum and introduced the Cooper-Frye hydrodynamic evolution to systematically study the pseudo-rapidity distributions of final charged hadrons at different energies and different centralities for Au-Au collisions in relativistic heavy-ion collisions at BNL Relativistic Heavy Ion Collider (RHIC). The features of both gluon saturation and hydrodynamic evolution at different energies and different centralities for Au-Au collisions are investigated in this paper.

  13. Hadron-Pair Photoproduction in Longitudinally Polarized Lepton-Nucleon Collisions

    E-Print Network [OSTI]

    Hendlmeier, C; Schäfer, A

    2006-01-01

    We present a detailed phenomenological study of photoproduction of two hadrons, both with high transverse momentum, in longitudinally polarized lepton-nucleon collisions. We consistently include ``direct'' and ``resolved'' photon contributions and examine the sensitivity of the relevant spin asymmetries to the gluon polarization in the nucleon and to the completely unknown parton content of circularly polarized photons. Our results are relevant for the COMPASS and HERMES fixed-target experiments as well as for a possible future polarized lepton-proton collider like eRHIC at BNL. So far, all studies are limited to the lowest order approximation of QCD.

  14. Hadron-Pair Photoproduction in Longitudinally Polarized Lepton-Nucleon Collisions

    E-Print Network [OSTI]

    C. Hendlmeier; M. Stratmann; A. Schafer

    2006-06-08

    We present a detailed phenomenological study of photoproduction of two hadrons, both with high transverse momentum, in longitudinally polarized lepton-nucleon collisions. We consistently include ``direct'' and ``resolved'' photon contributions and examine the sensitivity of the relevant spin asymmetries to the gluon polarization in the nucleon and to the completely unknown parton content of circularly polarized photons. Our results are relevant for the COMPASS and HERMES fixed-target experiments as well as for a possible future polarized lepton-proton collider like eRHIC at BNL. So far, all studies are limited to the lowest order approximation of QCD.

  15. Study of Micro Pixel Photon Counters for a high granularity scintillator-based hadron calorimeter

    E-Print Network [OSTI]

    D'Ascenzo, N; Garutti, E

    2007-01-01

    A new Geiger mode avalanche photodiode, the Micro Pixel Photon Counter (MPPC), was recently released by Hamamatsu. It has a high photo-detection efficiency in the 420 nm spectral region. This product can represent an elegant candidate for the design of a high granularity scintillator based hadron calorimeter for the International Linear Collider. In fact, the direct readout of the blue scintillation photons with a MPPC is a feasible techological solution. The readout of a plastic scintillator by a MPPC, both mediated by the traditional wavelength shifting fiber, and directly coupled, has been systematically studied.

  16. Hadronic shift in pionic hydrogen

    E-Print Network [OSTI]

    Hennebach, M; Dax, A; Fuhrmann, H; Gotta, D; Gruber, A; Hirtl, A; Indelicato, P; Liu, Y -W; Manil, B; Markushin, V E; Hassani, A J Rusi el; Simons, L M; Trassinelli, M; Zmeskal, J

    2014-01-01

    The hadronic shift in pionic hydrogen has been redetermined to be $\\epsilon_{1s}=7.086\\,\\pm\\,0.007(stat)\\,\\pm\\,0.006(sys)$\\,eV by X-ray spectroscopy of ground state transitions applying various energy calibration schemes. The experiment was performed at the high-intensity low-energy pion beam of the Paul Scherrer Institut by using the cyclotron trap and an ultimate resolution bent crystal Bragg spectrometer.

  17. Hadronic shift in pionic hydrogen

    E-Print Network [OSTI]

    M. Hennebach; D. F. Anagnostopoulos; A. Dax; H. Fuhrmann; D. Gotta; A. Gruber; A. Hirtl; P. Indelicato; Y. -W. Liu; B. Manil; V. E. Markushin; A. J. Rusi el Hassani; L. M. Simons; M. Trassinelli; J. Zmeskal

    2014-12-17

    The hadronic shift in pionic hydrogen has been redetermined to be $\\epsilon_{1s}=7.086\\,\\pm\\,0.007(stat)\\,\\pm\\,0.006(sys)$\\,eV by X-ray spectroscopy of ground state transitions applying various energy calibration schemes. The experiment was performed at the high-intensity low-energy pion beam of the Paul Scherrer Institut by using the cyclotron trap and an ultimate-resolution Bragg spectrometer with bent crystals.

  18. Summary audit report on lessons learned from the Superconducting Super Collider Project

    SciTech Connect (OSTI)

    1996-04-23

    In October 1993, the Congress decided to terminate the Superconducting Super Collider (SSC) project after expending about $1.57 billion on the project. While both internal and external factors contributed to the demise of the project, its cancellation offers the Department a unique opportunity to analyze what went wrong, correct the mistakes, and apply the lessons learned to future large-scale projects.

  19. SHIELDING OF SUPERCONDUCTING COILS FOR A 4-MW MUON-COLLIDER TARGET SYSTEM

    E-Print Network [OSTI]

    McDonald, Kirk

    SHIELDING OF SUPERCONDUCTING COILS FOR A 4-MW MUON-COLLIDER TARGET SYSTEM R.J. Weggel , N. Souchlas intercoil gaps to 40% of the O.D. of the flanking coils. Longitudinal sag of the tungsten shielding vessels an aggregate cross section of 0.1 m2 ; the cryogenic heat leakage may be large. The innermost shielding vessel

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

    SciTech Connect (OSTI)

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

    1993-01-29

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

  1. The Next Linear Collider: NLC2001

    SciTech Connect (OSTI)

    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.

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

    SciTech Connect (OSTI)

    Frisch, Josef; Decker, Valentin; Doyle, Eric; Hendrickson, Linda; Himel, Thomas; Markiewicz, Thomas; Seryi, Andrei; /SLAC; 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.

  3. Beam instrumentation for the Tevatron Collider

    SciTech Connect (OSTI)

    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.

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

    E-Print Network [OSTI]

    Crittenden, J.?A.

    2014-01-01

    cloud effects in the International Linear Collider positroninstability in the International Linear Collider positronin the proposed International Linear Collider (ILC) [3].

  5. Modeling a Large Data Acquisition Network in a Simulation Framework

    E-Print Network [OSTI]

    Colombo, Tommaso; The ATLAS collaboration

    2015-01-01

    The ATLAS detector at CERN records particle collision “events” delivered by the Large Hadron Collider. Its data-acquisition system is a distributed software system that identifies, selects, and stores interesting events in near real-time, with an aggregate throughput of several 10 GB/s. It is a distributed software system executed on a farm of roughly 2000 commodity worker nodes communicating via TCP/IP on an Ethernet network. Event data fragments are received from the many detector readout channels and are buffered, collected together, analyzed and either stored permanently or discarded. This system, and data-acquisition systems in general, are sensitive to the latency of the data transfer from the readout buffers to the worker nodes. Challenges affecting this transfer include the many-to-one communication pattern and the inherently bursty nature of the traffic. In this paper we introduce the main performance issues brought about by this workload, focusing in particular on the so-called TCP incast pathol...

  6. Charm particle production in hadronic collisions

    E-Print Network [OSTI]

    C. Avila; J. Magnin; L. M. Mendoza-Navas

    2006-12-21

    We study charm particle production in hadron-hadron collisions. After calculating perturbatively the charm quark differential cross section, we study the hadronization mechanisms. It is shown that recombination is the key to understand the so called Leading Particle Effect in charm meson production. For charm baryon production, however, leading particle effects are due to a combination of contributions coming from both, the recombination and the fragmentation mechanisms. We compare our calculations to experimental data on charm hadron production in $\\pi^- N$ and $p N$ interactions from several experiments and show that a consistent description of them can be reached without the aid of other mechanims than recombination and fragmentation.

  7. Heavy flavor production from photons and hadrons

    SciTech Connect (OSTI)

    Heusch, C.A.

    1982-01-01

    The present state of the production and observation of hadrons containing heavy quarks or antiquarks as valence constituents, in reactions initiated by real and (space-like) virtual photon or by hadron beams is discussed. Heavy flavor production in e/sup +/e/sup -/ annihilation, which is well covered in a number of recent review papers is not discussed, and similarly, neutrino production is omitted due to the different (flavor-changing) mechanisms that are involved in those reactions. Heavy flavors from spacelike photons, heavy flavors from real photons, and heavy flavors from hadron-hadron collisions are discussed. (WHK)

  8. Factorization for hadronic heavy quarkonium production

    E-Print Network [OSTI]

    Jian-Wei Qiu

    2006-10-31

    We briefly review several models of heavy quarkonium production in hadronic collisions, and discuss the status of QCD factorization for these production models.

  9. Precision Measurements at a Muon Collider

    E-Print Network [OSTI]

    S. Dawson

    1995-12-08

    We discuss the potential for making precision measurements of $M_W$ and $M_T$ at a muon collider and the motivations for each measurement. A comparison is made with the precision measurements expected at other facilities. The measurement of the top quark decay width is also discussed.

  10. Physics Case for the International Linear Collider

    E-Print Network [OSTI]

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

    2015-06-26

    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. Physics Case for the International Linear Collider

    E-Print Network [OSTI]

    Fujii, Keisuke; 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

    2015-01-01

    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.

  12. Hadronic matrix elements of neutral-meson mixing through lattice QCD

    E-Print Network [OSTI]

    C. C. Chang

    2015-09-23

    Neutral-meson mixing is loop suppressed in the Standard Model, leading to the possibility of enhanced sensitivity to new physics. The uncertainty in Standard Model predictions for $B$-meson oscillation frequencies is dominated by theoretical uncertainties within the short-distance $B$-meson hadronic matrix elements, motivating the need for improved precision. In $D$-meson mixing, the Standard Model short-distance contributions are further suppressed by the GIM mechanism allowing for the possibility of large new physics enhancements. A first-principle determination of the $D$-meson short-distance hadronic matrix elements will allow for model-discrimination between the new physics theories. I review recently published and ongoing lattice calculations of hadronic matrix elements in $B$ and $D$-meson mixing with emphasis on the Fermilab lattice and MILC collaboration effort on the determination of the $B$ and $D$-meson mixing hadronic matrix elements using the methods of lattice QCD.

  13. PHYSICS WITH AND PHYSICS OF COLLIDING ELECTRON BEAMS

    E-Print Network [OSTI]

    Pellegrini, Claudio

    2008-01-01

    contributed so much to the physics of colliding beams, theyto reap so little from the physics with colliding beams.Conference on High-Energy Physics, Vienna" September 1968 (

  14. Exploring Geometries of SRF Cavities for a Future Muon Collider

    E-Print Network [OSTI]

    Geng, Rong-Li

    application of super- conducting RF cavities in a future muon collider. Such RF cavities are expected to workExploring Geometries of SRF Cavities for a Future Muon Collider Rong-Li Geng LEPP, Cornell

  15. AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR COLLIDER

    E-Print Network [OSTI]

    AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR COLLIDER DAMPING RINGS Urban ALL RIGHTS RESERVED #12;AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR Linear Collider (ILC) damping rings. Results from optimizations of the parameters of this wiggler

  16. AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR COLLIDER

    E-Print Network [OSTI]

    AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR COLLIDER DAMPING RINGS Urban ALL RIGHTS RESERVED #12; AN OPTIMIZED SUPERFERRIC WIGGLER DESIGN FOR THE INTERNATIONAL LINEAR Linear Collider (ILC) damping rings. Results from optimizations of the parameters of this wiggler

  17. Hadron Structure from Lattice QCD

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-Dose Lowï‚—34 Revision 0August 9, 2012115Hadron

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

    ScienceCinema (OSTI)

    None

    2011-10-06

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

  19. Druid, displaying root module used for linear collider detectors

    E-Print Network [OSTI]

    Ruan, M

    2015-01-01

    Based on the ROOT TEve/TGeo classes and the standard linear collider data structure, a dedicated linear collider event display has been developed. It supports the latest detector models for both International Linear Collider and Compact Linear Collider as well as the CALICE test beam prototypes. It can be used to visualise event information at the generation, simulation and reconstruction levels. Many options are provided in an intuitive interface. It has been heavily employed in a variety of analyses.

  20. CLIC e+e- Linear Collider Studies

    E-Print Network [OSTI]

    Dominik Dannheim; Philippe Lebrun; Lucie Linssen; Daniel Schulte; Frank Simon; Steinar Stapnes; Nobukazu Toge; Harry Weerts; James Wells

    2012-08-07

    This document provides input from the CLIC e+e- linear collider studies to the update process of the European Strategy for Particle Physics. It is submitted on behalf of the CLIC/CTF3 collaboration and the CLIC physics and detector study. It describes the exploration of fundamental questions in particle physics at the energy frontier with a future TeV-scale e+e- linear collider based on the Compact Linear Collider (CLIC) two-beam acceleration technique. A high-luminosity high-energy e+e- collider allows for the exploration of Standard Model physics, such as precise measurements of the Higgs, top and gauge sectors, as well as for a multitude of searches for New Physics, either through direct discovery or indirectly, via high-precision observables. Given the current state of knowledge, following the observation of a \\sim125 GeV Higgs-like particle at the LHC, and pending further LHC results at 8 TeV and 14 TeV, a linear e+e- collider built and operated in centre-of-mass energy stages from a few-hundred GeV up to a few TeV will be an ideal physics exploration tool, complementing the LHC. Two example scenarios are presented for a CLIC accelerator built in three main stages of 500 GeV, 1.4 (1.5) TeV, and 3 TeV, together with the layout and performance of the experiments and accompanied by cost estimates. The resulting CLIC physics potential and measurement precisions are illustrated through detector simulations under realistic beam conditions.

  1. nuSTORM and A Path to a Muon Collider

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    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 ?+?- 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 ?+?-collider concept and describes how nuSTORM provides a platform to test advanced concepts for six-dimensional muon ionization cooling.« less

  2. Freeze-In Dark Matter with Displaced Signatures at Colliders

    E-Print Network [OSTI]

    Co, Raymond T; Hall, Lawrence J; Pappadopulo, Duccio

    2015-01-01

    Dark matter, $X$, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature $T_R \\ll {\\rm TeV}$. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle $B$ of the thermal bath, $B \\rightarrow X$. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leads to displaced signals at LHC and future colliders, for any $m_X$ in the range ${\\rm keV} < m_X < m_B$ and for values of $m_B$ accessible to these colliders. This result applies whether the early MD era arises after conventional inflation, when $T_R$ is the usual reheat temperature, or is a generic MD era with an alternative origin. I...

  3. COLLIDING PULSE INJECTION CONTROL IN A LASER-PLASMA ACCELERATOR

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    COLLIDING PULSE INJECTION CONTROL IN A LASER-PLASMA ACCELERATOR C.G.R. Geddes , G.R. Plateau, M is presented using the beat between two 'collid- ing' laser pulses to kick electrons into the plasma wake laser pulses [12, 13, 14, 15]. In the colliding pulse technique, the ponderomotive force of the beat

  4. A Survey of Hadron Therapy Accelerator Technologies.

    SciTech Connect (OSTI)

    PEGGS,S.; SATOGATA, T.; FLANZ, J.

    2007-06-25

    Hadron therapy has entered a new age [1]. The number of facilities grows steadily, and 'consumer' interest is high. Some groups are working on new accelerator technology, while others optimize existing designs by reducing capital and operating costs, and improving performance. This paper surveys the current requirements and directions in accelerator technology for hadron therapy.

  5. The Common Elements of Atomic and Hadronic Physics (Conference...

    Office of Scientific and Technical Information (OSTI)

    The Common Elements of Atomic and Hadronic Physics Citation Details In-Document Search Title: The Common Elements of Atomic and Hadronic Physics You are accessing a document...

  6. The Common Elements of Atomic and Hadronic Physics (Conference...

    Office of Scientific and Technical Information (OSTI)

    The Common Elements of Atomic and Hadronic Physics Citation Details In-Document Search Title: The Common Elements of Atomic and Hadronic Physics Authors: Brodsky, Stanley J. ;...

  7. Twist-3 fragmentation effects for ALT in light hadron production...

    Office of Scientific and Technical Information (OSTI)

    Twist-3 fragmentation effects for ALT in light hadron production from proton-proton collisions Title: Twist-3 fragmentation effects for ALT in light hadron production from...

  8. Probing the Color Glass Condensate in an electron-ion collider

    E-Print Network [OSTI]

    M. S. Kugeratski; V. P. Goncalves; F. S. Navarra

    2006-02-24

    Perturbative Quantum Chromodynamics (pQCD) predicts that the small-$x$ gluons in a hadron wavefunction should form a Color Glass Condensate (CGC), characterized by a saturation scale $Q_s (x, A)$ which is energy and atomic number dependent. In this paper we study the predictions of CGC physics for electron - ion collisions at high energies. We consider that the nucleus at high energies acts as an amplifier of the physics of high parton densities and estimate the nuclear structure function $F_2^A(x,Q^2)$, as well as the longitudinal and charm contributions, using a generalization for nuclear targets of the Iancu-Itakura-Munier model which describes the $ep$ HERA data quite well. Moreover, we investigate the behavior of the logarithmic slopes of the total and longitudinal structure functions in the kinematical region of the future electron - ion collider eRHIC.

  9. Physics at International Linear Collider (ILC)

    E-Print Network [OSTI]

    Hitoshi Yamamoto

    2007-09-06

    International Linear Collider (ILC) is an electron-positron collider with the initial center-of-mass energy of 500 GeV which is upgradable to about 1 TeV later on. Its goal is to study the physics at TeV scale with unprecedented high sensitivities. The main topics include precision measurements of the Higgs particle properties, studies of supersymmtric particles and the underlying theoretical structure if supersymmetry turns out to be realized in nature, probing alternative possibilities for the origin of mass, and the cosmological connections thereof. In many channels, Higgs and leptonic sector in particular, ILC is substantially more sensitive than LHC, and is complementary to LHC overall. In this short article, we will have a quick look at the capabilities of ILC.

  10. Luminosity Spectrum Reconstruction at Linear Colliders

    E-Print Network [OSTI]

    Stéphane Poss; André Sailer

    2014-04-11

    A good knowledge of the luminosity spectrum is mandatory for many measurements at future e+e- colliders. As the beam-parameters determining the luminosity spectrum cannot be measured precisely, the luminosity spectrum has to be measured through a gauge process with the detector. The measured distributions, used to reconstruct the spectrum, depend on Initial State Radiation, cross-section, and Final State Radiation. To extract the basic luminosity spectrum, a parametric model of the luminosity spectrum is created, in this case the spectrum at the 3 TeV Compact Linear Collider (CLIC). The model is used within a reweighting technique to extract the luminosity spectrum from measured Bhabha event observables, taking all relevant effects into account. The centre-of-mass energy spectrum is reconstructed within 5% over the full validity range of the model. The reconstructed spectrum does not result in a significant bias or systematic uncertainty in the exemplary physics benchmark process of smuon pair production.

  11. Civil Engineering Feasibility Studies for Future Ring Colliders at CERN

    E-Print Network [OSTI]

    Bruning, O; Myers, S; Osborne, J; Rossi, L; Waaijer, C; Zimmermann, F

    2013-01-01

    CERN civil engineers are studying the feasibility of several potential ring colliders to complement the LHC: an 80km circular tunnel to house the TLEP and VHE-LHC, and the ring-ring and linac-ring options for the LHeC. The feasibility of these projects is largely dependent on civil design and geotechnical and environmental risks. As civil infrastructure works typically represent one third of the cost of major physics projects, it is critical that the construction costs are well understood from the conceptual stage. This proceeding presents the first results of the feasibility studies for the 80km tunnel and the linac-ring LHeC. Presented at IPAC'13 Shanghai, 12-17 May 2013

  12. Multifragmentation at the balance energy of mass asymmetric colliding nuclei

    E-Print Network [OSTI]

    Supriya Goyal

    2011-06-20

    Using the quantum molecular dynamics model, we study the role of mass asymmetry of colliding nuclei on the fragmentation at the balance energy and on its mass dependence. The study is done by keeping the total mass of the system fixed as 40, 80, 160, and 240 and by varying the mass asymmetry of the ($\\eta$ = $\\frac{A_{T}-A_{P}}{A_{T}+A_{P}}$; where $A_{T}$ and $A_{P}$ are the masses of the target and projectile, respectively) reaction from 0.1 to 0.7. Our results clearly indicate a sizeable effect of the mass asymmetry on the multiplicity of various fragments. The mass asymmetry dependence of various fragments is found to increase with increase in total system mass (except for heavy mass fragments). Similar to symmetric reactions, a power law system mass dependence of various fragment multiplicities is also found to exit for large asymmetries.

  13. Extra dimensions and Seesaw Neutrinos at the International Linear Collider

    E-Print Network [OSTI]

    Tomoyuki Saito; Masaki Asano; Keisuke Fujii; Naoyuki Haba; Shigeki Matsumoto; Takehiro Nabeshima; Yosuke Takubo; Hitoshi Yamamoto; Koichi Yoshioka

    2010-11-27

    We study the capability of the international linear collider (ILC) to probe extra dimensions via the seesaw mechanism. In the scenario we study, heavy Kaluza-Klein neutrinos generate tiny neutrino masses and, at the same time, have sizable couplings to the standard-model particles. Consequently, a Kaluza-Klein tower of heavy neutrinos (N) can be produced and studied at the ILC through the process: e+e- -> vN followed by N -> Wl decay. We show that the single lepton plus two-jets final states with large missing energy from this signal process will provide a good opportunity to measure the masses and cross sections of Kaluza-Klein neutrinos up to the third level. Furthermore, the neutrino oscillation parameters can be extracted from the flavor dependence of the lowest-mode signals, which give us information about the origin of low-energy neutrino masses.

  14. COMMISSIONING OF THE RELATIVISTIC HEAVY ION COLLIDER.

    SciTech Connect (OSTI)

    TRBOJEVIC,D.; AHRENS,L.; BLASKIEWICZ,M.; BRENNAN,M.; BAI,M.; CAMERON,P.; CARDONA,J.; CONNOLLY,R.; ET AL; TSOUPAS,N.; VAN ZEIJTS,J.

    2001-06-18

    This report describes in detail steps performed in bringing the Relativistic Heavy Ion Collider (RHIC) from the commissioning into the operational stage when collisions between 60 bunches of fully striped gold ions, were routinely provided. Corrections of the few power supplies connections by the beam measurements are described. Beam lifetime improvements at injection, along the acceleration are shown. The beam diagnostic results; like Schottky detector, beam profile monitor, beam position monitors, tune meter and others, are shown [1].

  15. Power Law in Hadron Production

    E-Print Network [OSTI]

    Gazdzicki, M; Gazdzicki, Marek; Gorenstein, Mark I.

    2001-01-01

    In high energy p+p interactions the mean multiplicity of neutral mesons (from eta to Upsilon) and the transverse mass spectra of pions (m_T= 1 - 15 GeV/c^2) reveal a remarkable universal behaviour: they follow, over 10 orders of magnitude, the same power law function: C m_(T)^(-P). This scaling is rather similar to that expected in the statistical description of hadron production: the parameter P plays the role of a temperature and the normalisation constant C is analogous to the system volume. The fundamental difference is, however, in the form of the distribution function. In order to reproduce the experimental results and preserve the basic structure of the statistical approach the Boltzmann factor e^(-E^*/T) appearing in standard statistical mechanics has to be substituted by a power law factor (E^*/\\Lambda)^(-P).

  16. Di-hadron SIDIS measurements at CLAS

    SciTech Connect (OSTI)

    Pisano, Silvia [Lab. Naz. Frascati, Frascati, Italy

    2014-06-01

    Semi-inclusive deep-inelastic scattering (SIDIS) is an essential tool to probe nucleon internal structure. Through single hadron SIDIS processes, indeed, it is possible to access the TMDs, containing information on both the longitudinal and transverse motion of the partons. In recent years, moreover, an increasing attention has been devoted to dihadron SIDIS. It constitutes the golden channel to access the higher-twist collinear Parton Distribution Functions e(x) and h{sub L}(x), so far only marginally known, whose extraction will complete the collinear description of the nucleon at the twist-3 level. The CLAS detector in the Hall-B at JLab, thanks to its large acceptance, is particularly suited for such measurements. Analyses aiming at the extraction of dihadron SIDIS Beam and Target-Spin Asymmetries are presently in progress. In these proceedings, preliminary results for the Beam-Spin Asymmetry are reported, together with a summary of the dihadron SIDIS experimental program at JLab.

  17. Measuring the Top Quark Yukawa Coupling at a Linear e^+e^- Collider

    E-Print Network [OSTI]

    Howard Baer; Sally Dawson; Laura Reina

    1999-06-17

    The cross section for the reaction $e^+e^- \\to t\\bar{t} H$ depends sensitively on the top quark Yukwawa coupling $\\lambda_t$. We calculate the rate for $t\\bar{t}H$ production, followed by the decay $H\\to b\\bar{b}$, for a Standard Model Higgs boson with 100 < m_H <130 GeV. We interface with ISAJET to generate QCD radiation, hadronization and particle decays. We also calculate the dominant $t\\bar{t}b\\bar{b}$ backgrounds from electroweak and QCD processes. We consider both semileptonic and fully hadronic decays of the $t\\bar{t}$ system. In our analysis, we attempt full reconstruction of the top quark and W boson masses in the generated events. The invariant mass of the remaining b-jets should show evidence of Higgs boson production. We estimate the accuracy with which $\\lambda_t$ can be measured at a linear e^+e^- collider. Our results, including statistical but not systematic errors, show that the top quark Yukawa coupling can be measured to 6-8 % accuracy with 1000 fb^{-1} at $E_{CM}=1 TeV$, assuming 100 % efficiency for b-jet tagging. The accuracy of the measurement drops to 17-22 % if only a 60 % efficiency for b-tagging is achieved.

  18. High-energy high-luminosity electron-ion collider eRHIC

    SciTech Connect (OSTI)

    Litvinenko, V.N.; Ben-Zvi, I.; Hammons, L.; Hao, Y.; Webb, S.; et al

    2011-08-09

    In this paper, we describe a future electron-ion collider (EIC), based on the existing Relativistic Heavy Ion Collider (RHIC) hadron facility, with two intersecting superconducting rings, each 3.8 km in circumference. The replacement cost of the RHIC facility is about two billion US dollars, and the eRHIC will fully take advantage and utilize this investment. We plan adding a polarized 5-30 GeV electron beam to collide with variety of species in the existing RHIC accelerator complex, from polarized protons with a top energy of 325 GeV, to heavy fully-striped ions with energies up to 130 GeV/u. Brookhaven's innovative design, is based on one of the RHIC's hadron rings and a multi-pass energy-recovery linac (ERL). Using the ERL as the electron accelerator assures high luminosity in the 10{sup 33}-10{sup 34} cm{sup -2} sec{sup -1} range, and for the natural staging of eRHIC, with the ERL located inside the RHIC tunnel. The eRHIC will provide electron-hadron collisions in up to three interaction regions. We detail the eRHIC's performance in Section 2. Since first paper on eRHIC paper in 2000, its design underwent several iterations. Initially, the main eRHIC option (the so-called ring-ring, RR, design) was based on an electron ring, with the linac-ring (LR) option as a backup. In 2004, we published the detailed 'eRHIC 0th Order Design Report' including a cost-estimate for the RR design. After detailed studies, we found that an LR eRHIC has about a 10-fold higher luminosity than the RR. Since 2007, the LR, with its natural staging strategy and full transparency for polarized electrons, became the main choice for eRHIC. In 2009, we completed technical studies of the design and dynamics for MeRHIC with 3-pass 4 GeV ERL. We learned much from this evaluation, completed a bottom-up cost estimate for this $350M machine, but then shelved the design. In the same year, we turned again to considering the cost-effective, all-in-tunnel six-pass ERL for our design of the high-luminosity eRHIC. In it, electrons from the polarized pre-injector will be accelerated to their top energy by passing six times through two SRF linacs. After colliding with the hadron beam in up to three detectors, the e-beam will be decelerated by the same linacs and dumped. The six-pass magnetic system with small-gap magnets will be installed from the start. We will stage the electron energy from 5 GeV to 30 GeV stepwise by increasing the lengths of the SRF linacs. We discuss details of eRHIC's layout in Section 3. We considered several IR designs for eRHIC. The latest one, with a 10 mrad crossing angle and {beta}* = 5 cm, takes advantage of newly commissioned Nb{sub 3}Sn quadrupoles. Section 4 details the eRHIC lattice and the IR layout. The current eRHIC design focuses on electron-hadron collisions. If justified by the EIC physics, we will add a 30 GeV polarized positron ring with full energy injection from eRHIC ERL. This addition to the eRHIC facility provide for positron-hadron collisions, but at a significantly lower luminosity than those attainable in the electron-hadron mode. As a novel high-luminosity EIC, eRHIC faces many technical challenges, such as generating 50 mA of polarized electron current. eRHIC also will employ coherent electron cooling (CeC) for the hadron beams. Staff at BNL, JLab, and MIT is pursuing vigorously an R&D program for resolving addressing these obstacles. In collaboration with Jlab, BNL plans experimentally to demonstrate CeC at the RHIC. We discuss the structure and the status of the eRHIC R&D in Section 5.

  19. Hadron Freeze-Out and Unruh Radiation

    E-Print Network [OSTI]

    Paolo Castorina; Alfredo Iorio; Helmut Satz

    2014-09-10

    We consider hadron production in high energy collisions as an Unruh radiation phenomenon. This mechanism describes the production pattern of newly formed hadrons and is directly applicable at vanishing baryochemical potential, mu = 0. It had already been found to correctly yield the hadronisation temperature, T_h = sqrt(sigma / 2 pi) = 165 MeV in terms of the string tension sigma. Here we show that the Unruh mechanism also predicts hadronic freeze-out conditions, giving s/T_h^3 = 3 pi^2 / 4 = 7.4 in terms of the entropy density s and E/N = \\sqrt(2 pi sigma) = 1.09 for the average energy per hadron. These predictions provide a theoretical basis for previous phenomenological results and are also in accord with recent lattice studies.

  20. Hadron Production in Heavy Ion Collisions

    E-Print Network [OSTI]

    Helmut Oeschler; Hans Georg Ritter; Nu Xu

    2009-08-12

    We review hadron production in heavy ion collisions with emphasis on pion and kaon production at energies below 2 AGeV and on partonic collectivity at RHIC energies.

  1. Direct Probes of Linearly Polarized Gluons inside Unpolarized Hadrons

    SciTech Connect (OSTI)

    Boer, Daniel; /Groningen, KVI; Brodsky, Stanley J.; /SLAC /Southern Denmark U., CP3-Origins; Mulders, Piet J.; /Brussels U., IIHE; Pisano, Cristian; /Cagliari U. /INFN, Cagliari

    2011-02-07

    We show that the unmeasured distribution of linearly polarized gluons inside unpolarized hadrons can be directly probed in jet or heavy quark pair production both in electron-hadron and hadron-hadron collisions. We present expressions for the simplest cos 2{phi} asymmetries and estimate their maximal value in the particular case of electron-hadron collisions. Measurements of the linearly polarized gluon distribution in the proton should be feasible in future EIC or LHeC experiments.

  2. Physics at the $e^+ e^-$ Linear Collider

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    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 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.

  3. Positron Polarization at the International Linear Collider

    E-Print Network [OSTI]

    P. Osland; N. Paver

    2005-07-15

    We review some recent arguments supporting the upgrade of the International Linear Collider by a polarized positron beam, in addition to the polarized electron beam. The examples presented here mainly focus on the impact of positron polarization on items relevant to new physics searches, such as the identification of novel interactions in fermion-pair production and the formulation of new CP-sensitive observables. In particular, in addition to the benefits from positron and electron longitudinal polarizations, the advantages in this field of having transverse polarization of both beams are emphasized.

  4. HEP Collider HPC Use, Prospects and Wishes

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    AFDC Printable Version Share this resource Send a link to EERE: Alternative Fuels Data Center Home Page to someone by E-mail Share EERE: Alternative Fuels Data Center Home Page on Facebook Tweet about EERE: Alternative Fuels Data Center Home Page on Twitter Bookmark EERE: Alternative Fuels Data Center Homesum_a_epg0_fpd_mmcf_m.xls" ,"Available from WebQuantityBonneville Power Administration would likeUniverse (Journalvivo Low-Dose Lowï‚— WeUpdateScience DeadlinesHEP Collider HPC

  5. Power Law in Hadron Production

    E-Print Network [OSTI]

    Marek Gazdzicki; Mark I. Gorenstein

    2001-08-14

    In high energy p+p(bar) interactions the mean multiplicity and transverse mass spectra of neutral mesons from eta to Upsilon (m = 0.5 - 10 GeV/c^2) and the transverse mass spectra of pions (m_T > 1 GeV/c^2) reveal a remarkable behaviour: they follow, over more than 10 orders of magnitude, the power-law function:The parameters C and P are energy dependent, but similar for all mesons produced at the same collision energy. This scaling resembles that expected in the statistical description of hadron production: the parameter P plays the role of a temperature and the normalisation constant C is analogous to the system volume. The fundamental difference is, however, in the form of the distribution function. In order to reproduce the experimental results and preserve the basic structure of the statistical approach the Boltzmann factor e^(-E/T) appearing in standard statistical mechanics has to be substituted by a power-law factor (E/Lambda)^(-P).

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

    E-Print Network [OSTI]

    Schroeder, C. B.

    2010-01-01

    LASER-PLASMA-ACCELERATOR-BASED ?? COLLIDERS ? C. B.linear col- lider based on laser-plasma-accelerators arediscussed, and a laser-plasma-accelerator-based gamma-

  7. A young person's view of the Superconducting Super Collider

    SciTech Connect (OSTI)

    Moya, A.

    1990-08-01

    This report gives a simple description of the Superconducting Super Collider, how it works, and what it is used for. (LSP)

  8. Far Future Colliders and Required R&D Program

    SciTech Connect (OSTI)

    Shiltsev, V.; /Fermilab

    2012-06-01

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

  9. CERN SL -AP EUROPEAN ORGANIZATION FOR NUCLEAR RESEARCH

    E-Print Network [OSTI]

    Keil, Eberhard

    discussions of the super-conducting dipoles and their development are in Chap- ter VI. The radio The Large Hadron Collider LHC E. Keil The Large Hadron Collider Project LHC was approved by the CERN Council Collider Project CERN CH - 1211 Geneva 23 Switzerland LHC Project Report 79 Abstract 23/10/96 1 #12;The

  10. Precision Polarimetry at the International Linear Collider

    E-Print Network [OSTI]

    C. Helebrant; D. Käfer; J. List

    2008-10-13

    The International Linear Collider (ILC) will collide polarised electrons and positrons at beam energies of 45.6 GeV to 250 GeV and optionally up to 500 GeV. To fully exploit the physics potential of this machine, not only the luminosity and beam energy have to be known precisely, but also the polarisation of the particles has to be measured with an unprecedented precision of dP/P ~ 0.25% for both beams. An overall concept of high precision polarisation measurements at high beam energies will be presented. The focus will be on the polarimeters (up- and downstream of the e+e- interaction point) embedded in the ILC beam delivery system. Some challenges concerning the design of the Compton spectrometers and the appropriate Cherenkov detectors for each polarimeter are discussed. Detailed studies of photodetectors and their readout electronics are presented focusing specifically on the linearity of the device, since this is expected to be the limiting factor on the precision of the polarisation measurement at the ILC.

  11. Hadronic production of thermal photons 

    E-Print Network [OSTI]

    Turbide, S.; Rapp, Ralf; Gale, C.

    2004-01-01

    )]. ................................................................................ 11? Figure 2-5. Internal Strain Gage Locations on Transverse Reinforcement, Concrete Core, and Concrete Cover [taken from Alberson (2009)]. .......................... 12? Figure 2-6. Brass Insert with Tip Installed in the Surface of the LSC [taken...-7. Transverse and Longitudinal Strain Locations on the LSC Specimens? Small Face 1 and Large Face 1 during the Initial Orientation. .................... 26? Figure 3-8. Transverse Surface Strains on the LSC Specimens? Small Face 1 and Large Face 1...

  12. Hadronization effects on the baryon-strangeness correlation in quark combination models

    E-Print Network [OSTI]

    Feng-lan Shao; Jun Song; Rui-qin Wang

    2015-05-12

    The baryon-strangeness correlation in the hadronization of the quark matter is studied within the quark combination mechanism. We calculate the correlation coefficient $C_{BS} = -3\\big(\\langle B S \\rangle -\\langle B\\rangle \\langle S\\rangle\\big)/\\big( \\langle S^2 \\rangle-\\langle S \\rangle^2 \\big)$ of initial hadrons produced from the deconfined free quark system with $C^{(q)}_{BS}=1$. The competition of the production of baryons against that of mesons is the key dynamics that is most relevant to the change of baryon-strangeness correlation during system hadronization. Results of quark combination under the Poisson statistics agree with the statistical model predictions for a hadron resonance gas at vanishing chemical potential but differ from those at relatively large chemical potentials. Results beyond Poisson statistics are also obtained and are compared with calculations of Lattice QCD in the phase boundary, giving the best agreement at temperature $T =163$ MeV. We predict the dependence of the $C_{BS}$ of hadron system on the baryon chemical potential and strangeness. These predictions are expected to be tested by the future Lattice QCD calculations at non-zero chemical potentials and/or by the Beam Energy Scan experiment of STAR Collaboration at RHIC.

  13. Breaking of the number-of-constituent-quark scaling for identified-particle elliptic flow as a signal of phase change in low-energy data taken at the BNL Relativistic Heavy Ion Collider (RHIC)

    E-Print Network [OSTI]

    J. Tian; J. H. Chen; Y. G. Ma; X. Z. Cai; F. Jin; G. L. Ma; S. Zhang; C. Zhong

    2009-06-29

    We argue that measurements of identified-particle elliptic flow in a wide energy range could shed light on the possible phase change in high-energy heavy ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC). When the hadronization process is dominated by quark coalescence, the number-of-constituent-quark (NCQ) scaling for the identified-particle elliptic flow can serve as a probe for studying the strong interacting partonic matter. In the upcoming RHIC low-energy runs, the NCQ scaling behavior may be broken because of the change of the effective degrees of freedom of the hot dense matter, which corresponds to the transition from the dominant partonic phase to the dominant hadronic phase. A multiphase transport model is used to present the dependence of NCQ scaling behavior on the different hadronization mechanisms.

  14. Bag model of hadrons, dual QCD thermodynamics and Quark-Gluon Plasma

    E-Print Network [OSTI]

    H. C. Chandola; Garima Punetha; H. Dehnen

    2015-05-16

    Using the grand canonical ensemble formulation of a multi-particle statistical system, the thermodynamical description of the dual QCD has been presented in terms of the bag model of hadrons and analyzed for the quark-gluon plasma phase of hadronic matter. The dual QCD bag construction has been shown to lead to the radial pressure on the bag surface in terms of the vector glueball masses of the magnetically condensed QCD vacuum. Constructing the grand canonical partition function to deal with the quark-gluon plasma phase of the non-strange hadrons, the energy density and the plasma pressure have been derived and used to understand the dynamics of the associated phase transition. The critical temperature for QGP-hadron phase transition has been derived and numerically estimated by using various thermodynamic considerations. A comparison of the values of the critical temperatures for QGP-hadron phase transition with those obtained for the deconfinement-phase transition, has been shown to lead to the relaxation of the system via a mixed phase of QGP and hot hadron gas. The associated profiles of the normalized energy density and the specific heat have been shown to lead to a huge latent heat generation and indicate the onset of a first-order QGP phase transition. The squared speed of sound has been shown to act as a physical measure of large thermodynamical fluctuations near transition point where it shows a large reduction in its value as compared to the conformal limit and has intimate connection with the evolution of fire-ball and QGP in heavy-ion collision events. The possible implications of the trace anomaly and conformal measure on QGP formation have been discussed and a considerable increase in the degrees of freedom and the associated interaction effects has been indicated around the transition region and discussed for its relevance with the modern heavy-ion collision experiments.

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

    E-Print Network [OSTI]

    Geddes, Cameron Guy Robinson

    Colliding Laser Pulses for Laser-Plasma Accelerator Injection Control G. R. Plateau, , C. G. R acceleration is a key challenge to achieve compact, reliable, tunable laser-plasma accelerators (LPA) [1, 2]. In colliding pulse injection the beat between multiple laser pulses can be used to control energy, energy

  16. VEPP-2000 COLLIDER CONTROL SYSTEM* A.Senchenko1,#

    E-Print Network [OSTI]

    Kozak, Victor R.

    VEPP-2000 COLLIDER CONTROL SYSTEM* A.Senchenko1,# , D.Berkaev1,2 , O.Gorbatenko1 , A.Kasaev1 , I of interacting subsystems responding on different acceleration facility parts. Control system software is based presents architecture, implementation and functionality of hardware and software of the collider control

  17. The Neutrino Factory and Muon Collider Collaboration Considerations on

    E-Print Network [OSTI]

    McDonald, Kirk

    Plenary Meeting, KEK Jan 24, 2006 http://puhep1.princeton.edu/mumu/target/ (Presented by M. Zisman) Kirk T.) Kirk T. McDonald ISS Plenary Meeting, KEK, Jan 24, 2006 2 #12;The Neutrino Factory and Muon Collider". Kirk T. McDonald ISS Plenary Meeting, KEK, Jan 24, 2006 3 #12;The Neutrino Factory and Muon Collider

  18. Helmholtz Alliance Linear Collider Forum Proceedings of the Workshops

    E-Print Network [OSTI]

    Helmholtz Alliance Linear Collider Forum Proceedings of the Workshops Hamburg, Munich, Hamburg 2010 of the Helmholtz Alliance Linear Collider Forum 2010­2012, Hamburg, M¨unchen, Hamburg, Germany Conference homepage, Internationales Congress Center, Dresden (at the 4th Annual Workshop of the Helmholtz Alliance `Physics

  19. CLIC Drive Beam and LHC Based Fel-Nucleus Collider

    E-Print Network [OSTI]

    H. Braun; R. Corsini; S. Sultansoy; O. Yavas

    2005-08-09

    The feasibility of a CLIC-LHC based FEL-nucleus collider is investigated. It is shown that the proposed scheme satisfies all requirements of an ideal photon source for the Nuclear Resonance Fluorescence method. The physics potential of the proposed collider is illustrated for a beam of Pb nuclei.

  20. CONTROL SYSTEM OF VEPP-2000 COLLIDER (SOFTWARE, HARDWARE)

    E-Print Network [OSTI]

    Kozak, Victor R.

    CONTROL SYSTEM OF VEPP-2000 COLLIDER (SOFTWARE, HARDWARE) D.E.Berkaev, P.B.Cheblakov, V, implementation and functionality of the software of the collider control system. The software according. Control system software is based on several TCP/IP connected PC platforms working under operating system

  1. Energy Content of Colliding Plane Waves using Approximate Noether Symmetries

    E-Print Network [OSTI]

    M. Sharif; Saira Waheed

    2011-09-19

    This paper is devoted to study the energy content of colliding plane waves using approximate Noether symmetries. For this purpose, we use approximate Lie symmetry method of Lagrangian for differential equations. We formulate the first-order perturbed Lagrangian for colliding plane electromagnetic and gravitational waves. It is shown that in both cases, there does not exist

  2. EIS-0138-S: Superconducting Super Collider, Supplemental, Waxahatchie, Texas

    Broader source: Energy.gov [DOE]

    The U.S. Department of Energy developed this supplementary statement to analyze the environmental impacts of design modifications to the Superconducting Super Collider that were made following the publication of the Record of Decision that selected Ellis County, Texas, as the location of the laboratory facility. This statement supplements DOE/EIS-0138, Superconducting Super Collider.

  3. PION PRODUCTION FOR NEUTRINO FACTORIES AND MUON COLLIDERS

    E-Print Network [OSTI]

    McDonald, Kirk

    PION PRODUCTION FOR NEUTRINO FACTORIES AND MUON COLLIDERS Workshop on Applications of High production for nufact/mu-collider - N.V. Mokhov Outline · Pion Production and Collection · Event Generators-independent analysis of HARP data 2 #12;AHIPA Workshop, Fermilab, October 19-21, 2009 Pion production for nufact

  4. Freeze-In Dark Matter with Displaced Signatures at Colliders

    E-Print Network [OSTI]

    Raymond T. Co; Francesco D'Eramo; Lawrence J. Hall; Duccio Pappadopulo

    2015-06-24

    Dark matter, $X$, may be generated by new physics at the TeV scale during an early matter-dominated (MD) era that ends at temperature $T_R \\ll {\\rm TeV}$. Compared to the conventional radiation-dominated (RD) results, yields from both Freeze-Out and Freeze-In processes are greatly suppressed by dilution from entropy production, making Freeze-Out less plausible while allowing successful Freeze-In with a much larger coupling strength. Freeze-In is typically dominated by the decay of a particle $B$ of the thermal bath, $B \\rightarrow X$. For a large fraction of the relevant cosmological parameter space, the decay rate required to produce the observed dark matter abundance leads to displaced signals at LHC and future colliders, for any $m_X$ in the range ${\\rm keV} < m_X < m_B$ and for values of $m_B$ accessible to these colliders. This result applies whether the early MD era arises after conventional inflation, when $T_R$ is the usual reheat temperature, or is a generic MD era with an alternative origin. In the former case, if $m_X$ is sufficiently large to be measured from kinematics, the reheat temperature $T_R$ can be extracted. Our result is independent of the particular particle physics implementation of $B \\rightarrow X$, and can occur via any operator of dimension less than 8 (4) for a post-inflation (general MD) cosmology. An interesting example is provided by DFS axion theories with TeV-scale supersymmetry and axino dark matter of mass GeV to TeV, which is typically overproduced in a conventional RD cosmology. If $B$ is the higgsino, $\\tilde h$, Higgs, W and Z particles appear at the displaced decays, $\\tilde h \\rightarrow h \\tilde a, Z \\tilde a$ and $\\tilde h^\\pm \\rightarrow W^\\pm \\tilde a$. The scale of axion physics, $f$, is predicted to be in the range $(3\\times10^8 - 10^{12})$ GeV and, over much of this range, can be extracted from the decay length.

  5. Measurement of the Top Quark Mass in the All-Hadronic Mode at CDF

    SciTech Connect (OSTI)

    Aaltonen, T.; Alvarez Gonzalez, B.; Amerio, S.; Amidei, D.; Anastassov, A.; Annovi, A.; Antos, J.; Apollinari, G.; Appel, J.A.; Arisawa, T.; Artikov, A.; /Dubna, JINR /Texas A-M

    2011-12-01

    A measurement of the top quark mass (M{sub top}) in the all-hadronic decay channel is presented. It uses 5.8 fb{sup -1} of p{bar p} data collected with the CDF II detector at the Fermilab Tevatron Collider. Events with six to eight jets are selected by a neural network algorithm and by the requirement that at least one of the jets is tagged as a b quark jet. The measurement is performed with a likelihood fit technique, which simultaneously determines M{sub top} and the jet energy scale (JES) calibration. The fit yields a value of M{sub top} = 172.5 {+-} 1.4 (stat) {+-} 1.0 (JES) {+-} 1.1 (syst) GeV/c{sup 2}.

  6. $?/s$ of a Relativistic Hadron Gas at RHIC: Approaching the AdS/CFT bound?

    E-Print Network [OSTI]

    N. Demir; S. A. Bass

    2009-09-18

    Ultrarelativistic heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) are thought to have produced a state of matter called the quark-gluon plasma, characterized by a very small shear-viscosity to entropy-density ratio $\\eta/s$, near the lower bound predicted for that quantity by AdS/CFT methods. As the produced matter expands and cools, it evolves through a phase described by a hadron gas with rapidly increasing $\\eta/s$. We calculate $\\eta/s$ as a function of temperature in this phase both in and out of chemical equilibrium and find that its value poses a challenge for viscous relativistic hydrodynamics, which requires small values of $\\eta/s$ in order to successfully describe the collective flow observables at RHIC. We therefore conclude that the origin of the low viscosity matter at the RHIC must be in the partonic phase of the reaction.

  7. Interaction region for crab waist scheme of the Future Electron-Positron Collider (CERN)

    E-Print Network [OSTI]

    Bogomyagkov, A

    2015-01-01

    Design study in CERN of the accelerator that would fit 80-100 km tunnel called Future Circular Colliders (FCC) includes high-luminosity $e^+ e^?$ collider (FCC-ee) with center-of-mass energy from 90 to 350 GeV to study Higgs boson properties and perform precise measurements at the electroweak scale [1–3]. Crab waist interaction region provides collisions with luminosity higher than 2 × 10$^{36}$ cm$^{?2}$ sec$^{?1}$ at beam energy of 45 GeV. The small values of the beta functions at the interaction point and distant final focus lenses are the reasons for high nonlinear chromaticity limiting energy acceptance of the whole ring. The paper describes interaction region for crab waist collision scheme in the FCC-ee, principles of tuning the chromaticity correction section in order to provide large energy acceptance.

  8. News from CERN, LHC Status and Strategy for Linear Colliders

    E-Print Network [OSTI]

    Rolf-Dieter Heuer

    2012-02-27

    This paper presents the latest development at CERN, concentrating on the status of the LHC and the strategy for future linear colliders. The immediate plans include the exploitation of the LHC at its design luminosity and energy as well as upgrades to the LHC (luminosity and energy) and to its injectors. This may be complemented by a linear electron-positron collider, based on the technology being developed by the Compact Linear Collider and by the International Linear Collider and/or by a high-energy electron-proton collider. This contribution describes the various 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.

  9. Fragmentation of colliding planetesimals with water content

    E-Print Network [OSTI]

    Maindl, Thomas I; Schäfer, Christoph; Speith, Roland

    2014-01-01

    We investigate the outcome of collisions of Ceres-sized planetesimals composed of a rocky core and a shell of water ice. These collisions are not only relevant for explaining the formation of planetary embryos in early planetary systems, but also provide insight into the formation of asteroid families and possible water transport via colliding small bodies. Earlier studies show characteristic collision velocities exceeding the bodies' mutual escape velocity which - along with the distribution of the impact angles - cover the collision outcome regimes 'partial accretion', 'erosion', and 'hit-and-run' leading to different expected fragmentation scenarios. Existing collision simulations use bodies composed of strengthless material; we study the distribution of fragments and their water contents considering the full elasto-plastic continuum mechanics equations also including brittle failure and fragmentation.

  10. Another Detector for the International Linear Collider

    E-Print Network [OSTI]

    Nural Akchurin; Sehwook Lee; Richard Wigmans; Hanna Arnold; Aaron Bazal; Robert Basili; John Hauptman; Tim Overton; Andrew Priest; Bingzhe Zhao; Alexander Mikhailichenko; Michele Cascella; Franco Grancagnolo; Giovanni Tassielli; Franco Bedeschi; Fabrizio Scuri; Sung Keun Park; Fedor Ignatov; Gabriella Gaudio; Michele Livan

    2013-07-25

    We describe another detectora designed for the International Linear Collider based on several tested instrumentation innovations in order to achieve the necessary experi- mental goal of a detecter that is 2-to-10 times better than the already excellent SLC and LEP detectors, in particular, (1) dual-readout calorimeter system based on the RD52/DREAM measurements at CERN, (2) a cluster-counting drift chamber based on the successful kloe chamber at Frascati, and (3) a second solenoid to return the magnetic flux without iron. A high-performance pixel vertex chamber is presently undefined. We discuss particle identification, momentum and energy resolutions, and the machine-detector interface that together offer the possibility of a very high-performance detector for $e^+e^-$physics up to $\\sqrt{s} = 1$ TeV.

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

    ScienceCinema (OSTI)

    None

    2011-10-06

    Calorimetry will play a central role in determining the physics reach at a future e+e- collider. The requirements for calorimetry place the emphasis on achieving an excellent jet energy resolution. The currently favoured option for calorimetry at a future e+e- collider is the concept of high granularity particle flow calorimetry. Here granularity and a high pattern recognition capability is more important than the single particle calorimetric response. In this lecture I will describe the recent progress in understanding the reach of high granularity particle flow calorimetry and the related R&D; efforts which concentrate on test beam demonstrations of the technological options for highly granular calorimeters. I will also discuss alternatives to particle flow, for example the technique of dual readout calorimetry.

  12. Spectral Change of Hadrons and Chiral Symmetry

    E-Print Network [OSTI]

    Tetsuo Hatsuda

    2001-04-16

    After a brief summary of the QCD phase structure with light quarks, we discuss two recent developments on in-medium hadrons. First topic is the sigma-meson which is a fluctuation of the chiral order parameter \\bar{q}q. Although sigma is at best a broad resonance in the vacuum, it may suffer a substantial red-shift and show a characteristic spectral enhancement at the 2 m_{pi} threshold at finite temperature and baryon density. Possible experimental signatures of this phenomenon are also discussed. Another topic is the first principle lattice QCD calculation of the hadronic spectral functions using the maximum entropy method (MEM). The basic idea and a successful example of MEM are presented. Possible applications of MEM to study the in-medium hadrons in lattice QCD simulations are discussed.

  13. Hadronic form factors in kaon photoproduction

    SciTech Connect (OSTI)

    Syukurilla, L. Mart, T.

    2014-09-25

    We have revisited the effect of hadronic form factors in kaon photoproduction process by utilizing an isobaric model developed for kaon photoproduction off the proton. The model is able to reproduce the available experimental data nicely as well as to reveal the origin of the second peak in the total cross section, which was the main source of confusion for decades. Different from our previous study, in the present work we explore the possibility of using different hadronic form factors in each of the K?N vertices. The use of different hadronic form factors, e.g. dipole, Gaussian, and generalized dipole, has been found to produce a more flexible isobar model, which can provide a significant improvement in the model.

  14. Technical Design of Hadron Therapy Facilities

    SciTech Connect (OSTI)

    Alonso, J.R.

    1993-08-01

    Radiation therapy with hadron beams now has a 40-year track record at many accelerator laboratories around the world, essentially all of these originally physics-research oriented. The great promise shown for treating cancer has led the medical community to seek dedicated accelerator facilities in a hospital setting, where more rapid progress can be made in clinical research. This paper will discuss accelerator and beam characteristics relevant to hadron therapy, particularly as applied to hospital-based facilities. A survey of currently-operating and planned hadron therapy facilities will be given, with particular emphasis on Lorna Linda (the first dedicated proton facility in a hospital) and HIMAC (the first dedicated heavy-ion medical facility).

  15. Technical design of hadron therapy facilities

    SciTech Connect (OSTI)

    Alonso, J.R.

    1993-08-01

    Radiation therapy with hadron beams now has a 40-year track record at many accelerator laboratories around the world, essentially all of these originally physics-research oriented. The great promise shown for treating cancer has led the medical community to seek dedicated accelerator facilities in a hospital setting, where more rapid progress can be made in clinical research. This paper will discuss accelerator and beam characteristics relevant to hadron therapy, particularly as applied to hospital-based facilities. A survey of currently-operating and planned hadron therapy facilities will be given, with particular emphasis on Loma Linda (the first dedicated proton facility in a hospital) and HIMAC (the first dedicated heavy-ion medical facility).

  16. Diagnosing Energy Loss: PHENIX Results on High-pT Hadron Spectra

    E-Print Network [OSTI]

    B. Sahlmueller

    2007-01-25

    Measurements of inclusive spectra of hadrons at large transverse momentum over a broad range of energy in different collision systems have been performed with the PHENIX experiment at RHIC. The data allow to study the energy and system size dependence of the suppression observed in RAA of high-pT hadrons at sqrt(s_NN)= 200 GeV. Due to the large energy range from sqrt(s_NN)= 22 GeV to 200 GeV, the results can be compared to results from CERN SPS at a similar energy. The large Au+Au dataset from the 2004 run of RHIC also allows to constrain theoretical models that describe the hot and dense matter produced in such collisions. Investigation of particle ratios such as eta/pi0 helps understanding the mechanisms of energy loss.

  17. Observation of New Charmless Decays of Bottom Hadrons

    E-Print Network [OSTI]

    Xie, Si

    We search for new charmless decays of neutral b hadrons to pairs of charged hadrons, using 1??fb[superscript -1] of data collected by the CDF II detector at the Fermilab Tevatron. We report the first observation of the ...

  18. Production of jets at forward rapidities in hadronic collisions

    E-Print Network [OSTI]

    F. Hautmann

    2009-09-07

    We discuss high-pT production processes at forward rapidities in hadron-hadron collisions, and describe recent results from using QCD high-energy factorization in forward jet production at the LHC.

  19. Systemsize dependence of associated yields in hadron-triggered jets

    E-Print Network [OSTI]

    Abelev, Betty

    2010-01-01

    in hadron-triggered jets B.I.Abelev (STARCollaboration)yields in hadron-triggered jets B. I. Abelev 8 , M. M.+Au collisions reveal similar jet-like correlation yields at

  20. Heavy quarkonium production at collider energies: Partonic cross section and polarization

    SciTech Connect (OSTI)

    Qiu, Jian -Wei [Brookhaven National Lab. (BNL), Upton, NY (United States); Stony Brook Univ., Stony Brook, NY (United States); Kang, Zhong -Bo [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Ma, Yan -Qing [Univ. of Maryland, College Park, MD (United States); Peking Univ., Beijing (China); Sterman, George [Stony Brook Univ., Stony Brook, NY (United States)

    2015-01-01

    We calculate the O(?³s) short-distance, QCD collinear-factorized coefficient functions for all partonic channels that include the production of a heavy quark pair at short distances. This provides the first power correction to the collinear-factorized inclusive hadronic production of heavy quarkonia at large transverse momentum, pT, including the full leading-order perturbative contributions to the production of heavy quark pairs in all color and spin states employed in NRQCD treatments of this process. We discuss the role of the first power correction in the production rates and the polarizations of heavy quarkonia in high-energy hadronic collisions. The consistency of QCD collinear factorization and nonrelativistic QCD factorization applied to heavy quarkonium production is also discussed.

  1. Heavy quarkonium production at collider energies: Partonic cross section and polarization

    DOE Public Access Gateway for Energy & Science Beta (PAGES Beta)

    Qiu, Jian -Wei; Kang, Zhong -Bo; Ma, Yan -Qing; Sterman, George

    2015-01-27

    We calculate the O(?³s) short-distance, QCD collinear-factorized coefficient functions for all partonic channels that include the production of a heavy quark pair at short distances. Thus, this provides the first power correction to the collinear-factorized inclusive hadronic production of heavy quarkonia at large transverse momentum, pT, including the full leading-order perturbative contributions to the production of heavy quark pairs in all color and spin states employed in NRQCD treatments of this process. We discuss the role of the first power correction in the production rates and the polarizations of heavy quarkonia in high-energy hadronic collisions. The consistency of QCD collinearmore »factorization and nonrelativistic QCD factorization applied to heavy quarkonium production is also discussed.« less

  2. Forschung fr den International Linear Collider Abbildung 55: Simuliertes Ereignis im Kalorimeter Prototypen fr den ILC. Drei Detektoren

    E-Print Network [OSTI]

    Forschung für den International Linear Collider Abbildung 55: Simuliertes Ereignis im Kalorimeter #12;Forschung für den International Linear Collider Forschung für den International Linear Collider Treffen der Maschinenexperten, eindrucks- voll demonstriert. Der Name ,,International Linear Collider

  3. Bottom and charmed hadron spectroscopy from lattice QCD

    E-Print Network [OSTI]

    Randy Lewis

    2010-10-05

    A survey of recent lattice QCD simulations for the mass spectrum of bottom and charmed hadrons is presented.

  4. The Polarized Electron Source for the International Collider (ILC) Project

    SciTech Connect (OSTI)

    Brachmann, A.; Clendenin, J.E.; Garwin, E.L.; Ioakeimidi, K.; Kirby, R.e.; Maruyama, T.; Prescott, C.Y.; Sheppard, J.; Turner, J.; Zhou, F.; /SLAC

    2006-12-01

    ILC project will be the next large high energy physics tool that will use polarized electrons (and positrons). For this machine spin physics will play an important role. The polarized electron source design is based on electron injectors built for the Stanford Linear Collider (polarized) and Tesla Test Facility (un-polarized). The ILC polarized electron source will provide a 5GeV spin polarized electron beam for injection into the ILC damping ring. Although most ILC machine parameters have been achieved by the SLC or TTF source, features of both must be integrated into one design. The bunch train structure presents unique challenges to the source laser drive system. A suitable laser system has not yet been demonstrated and is part of the ongoing R&D program for ILC at SLAC. Furthermore, ILC injector R&D incorporates photocathode development, increasing available polarization, and improving operational properties in gun vacuum systems. Another important area of research and development is advancing the design of DC and RF electron gun technology for polarized sources. This presentation presents the current status of the design and outlines aspects of the relevant R&D program carried out within the ILC community.

  5. Hydrodynamics and High-Energy Physics of WR Colliding Winds

    E-Print Network [OSTI]

    Vladimir V. Usov

    1994-05-29

    One of the main properties of Wolf-Rayet (WR) stars is a very intense outflow of gas. No less than 40\\% \\ of WR stars belong to binary systems. Young massive O and B stars are the secondary components of such systems. OB stars also have an intense stellar wind. If the intensities of the stellar winds of WR and OB stars are more or less comparable or if the distance between the components of the binary is large enough, the winds flowing out of WR and OB stars can collide and the shock waves are formed. In the shock the gas is heated to temperature $\\sim 10^7$ K and generates X-ray emission. Stellar wind collision may be responsible not only for the X-ray emission of WR + OB binaries and for their radio, IR and $\\gamma$-ray emision as well. Stellar wind collision, gas heating, particle acceleration, and generation of X-ray, $\\gamma$-ray, radio and IR emission in WR + OB binaries are discussed.

  6. Single-Bunch Instability Driven by the Electron Cloud Effect in the Positron Damping Ring of the International Linear Collider

    E-Print Network [OSTI]

    2005-01-01

    RING OF THE INTERNATIONAL LINEAR COLLIDER* M. Pivi # , T.DR) of the International Linear Collider (ILC), an electron

  7. Measurement of the hadronic cross section in electron-positron annihilation

    SciTech Connect (OSTI)

    Clearwater, S.

    1983-11-01

    This thesis describes the most precise measurement to date of the ratio R, the hadronic cross section in lowest order electron-positron annihilation to the cross section for muon pair production in lowest order electron-positron annihilation. This experiment is of interest because R is a fundamental parameter that tests in a model independent way the basic assumptions of strong interaction theories. According to the assumptions of one of these theories the value of R is determined simply from the electric charges, spin, and color assignments of the produced quark-pairs. The experiment was carried out with the MAgnetic Calorimeter using collisions of 14.5 GeV electrons and positrons at the 2200m circumference PEP storage ring at SLAC. The MAC detector is one of the best-suited collider detectors for measuring R due to its nearly complete coverage of the full angular range. The data for this experiment were accumulated between February 1982 and April 1983 corresponding to a total event sample of about 40,000 hadronic events. About 5% of the data were taken with 14 GeV beams and the rest of the data were taken with 14.5 GeV beams. A description of particle interactions and experimental considerations is given.

  8. Estimation of charm production cross section in hadronic interactions at high energies

    E-Print Network [OSTI]

    G. M. Vereshkov; Yu. F. Novoseltsev

    2004-04-24

    Results of processing experimental data on charm production in hadron-hadron interactions are presented. The analysis is carried out within the frame of phenomenological model of diffraction production and quark statistics based on additive quark model (AQM). In low energy region sqrt s = 20 - 40GeV, the cross sections si_ {pN to c bar cX} (s), si_ {pi N to c bar cX} (s) are fitted by logarithmic function with the parameters connected by relationship of AQM. At collider energies 200, 540, 900, 1800 GeV, the values of si_{bar pp to c bar cX} (s) were obtained by a quark statistics method from the data on diffraction dissociation. It is established, that logarithmic function with universal numerical parameters describes the whole set of low-energy and high-energy data with high accuracy. The expected values of cross sections are si_{pp to c bar cX} = 250 pm 40 mu b and 355 pm 57 mu b at TEVATRON energy sqrt {s} = 1.96 TeV and LHC energy sqrt {s} = 14 TeV accordingly. Opportunities of use of the obtained results for calibration of a flux of "prompt" muons in high-energy component of cosmic rays are discussed.

  9. Energy flow observables in hadronic collisions

    E-Print Network [OSTI]

    F. Hautmann

    2012-05-24

    We present recent QCD calculations of energy flow distributions associated with the production of jets at wide rapidity separations in high-energy hadron collisions, and discuss the role of these observables to analyze contributions from parton showering and from multiple parton collisions.

  10. The Naked Truth about Hadronic Regge Trajectories

    E-Print Network [OSTI]

    A. E. Inopin

    2000-12-19

    We have reconstructed Regge trajectories (RT), using all existing data on masses and spin-parities of all currently known hadrons. In this resonance energy region meson and baryon RT are grossly nonlinear, and only 12% of all RT could be classified as a linear, with $\\sigma=0$, $\\alpha'\\simeq 0.9$ GeV${}^{-2}$.

  11. The Pion Cloud: Insights into Hadron Structure

    E-Print Network [OSTI]

    A. W. Thomas

    2007-11-14

    Modern nuclear theory presents a fascinating study in contrasting approaches to the structure of hadrons and nuclei. Nowhere is this more apparent than in the treatment of the pion cloud. As this discussion really begins with Yukawa, it is entirely appropriate that this invited lecture at the Yukawa Institute in Kyoto should deal with the issue.

  12. Hadron structure at small momentum transfer

    E-Print Network [OSTI]

    Thomas Walcher

    2008-01-12

    Giving three examples, the form factors of the nucleon, the polarisability of the charged pion and the interference of the $S_{11}(1535)$ with the $D_{13}(1520)$ excitation of the nucleon in the $\\eta p$-decay channel, it is argued that the hadron structure at low momentum transfer is highly significant for studying QCD.

  13. Electromagnetic corrections to light hadron masses

    E-Print Network [OSTI]

    A. Portelli; S. Dürr; Z. Fodor; J. Frison; C. Hoelbling; S. D. Katz; S. Krieg; T. Kurth; L. Lellouch; T. Lippert; K. K. Szabó; A. Ramos

    2011-01-12

    At the precision reached in current lattice QCD calculations, electromagnetic effects are becoming numerically relevant. We will present preliminary results for electromagnetic corrections to light hadron masses, based on simulations in which a $\\mathrm{U}(1)$ degree of freedom is superimposed on $N_f=2+1$ QCD configurations from the BMW collaboration.

  14. Emergence String and Mass Formulas of Hadrons

    E-Print Network [OSTI]

    Yi-Fang Chang

    2011-07-19

    Assume that hadrons are formed from the emergence string. Usual string should possess two moving states: oscillation and rotation, so we propose corresponding potential and the equation of the emergence string, whose energy spectrum is namely the GMO mass formula and its modified accurate mass formula. These are some relations between the string and observable experimental data.

  15. Rho Meson in Dense Hadronic Matter 

    E-Print Network [OSTI]

    Asakawa, M.; Ko, Che Ming; Levai, P.; Qiu, X. J.

    1992-01-01

    The spectral function of a rho meson that is at rest in dense hadronic matter and couples strongly to the pion is studied in the vector dominance model by including the effect of the delta-hole polarization on the pion. With the free rho-meson mass...

  16. Hadronic transitions ?(2S)??(1S)

    E-Print Network [OSTI]

    Ammar, Raymond G.; Baringer, Philip S.; Bean, Alice; Besson, David Zeke; Coppage, Don; Darling, C.; Davis, Robin E. P.; Kotov, S.; Kravchenko, I.; Kwak, Nowhan; Zhou, L.

    1998-08-07

    Using a 73.6pb(-1) data sample of ?(2S) events collected with the CLEO II detector at the Cornell Electron Storage Ring, we have investigated the hadronic transitions between the ?(2S) and the ?(1S). The dipion transition ...

  17. Press Pass - Press Releases

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    09 Press Release Archive Recent Releases Beams are Back in the Large Hadron Collider 112009 Fermilab seeks nominations for new Community Advisory Board to assist in future...

  18. Fermilab | Newsroom | Press Releases | March 14, 2013: New evidence...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    Laboratory and Brookhaven National Laboratory. Fermilab is heavily involved in the Higgs boson research at the Large Hadron Collider. The Illinois laboratory serves as the...

  19. Fermilab | Newsroom | Press Releases | July 2, 2012: Tevatron...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Accelerator Laboratory. "Our data strongly point toward the existence of the Higgs boson, but it will take results from the experiments at the Large Hadron Collider in...

  20. Fermilab | Newsroom | Press Releases | July 4, 2012: Search for...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    that scientists, engineers and students from Fermilab have made to the LHC." Search for Higgs boson at Large Hadron Collider reveals new particle Physicists on experiments at the...

  1. ATLAS/BNL Physicist Marc-Andre Pleier Explains the Higgs Mechanism

    SciTech Connect (OSTI)

    Pleier,Marc-Andre

    2013-10-07

    ATLAS/BNL Physicist Marc-Andre Pleier explains his role in analyzing data from the Large Hadron Collider and the search for the Higgs boson

  2. Jefferson Lab and Jefferson Science Associates Bring First School...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    halls. A videoconference with the CERN particle physics laboratory in Geneva, Switzerland, will link students with physicists operating the Large Hadron Collider from CERN's...

  3. Quark Flavors and Conserved Charges at Finite Density in the...

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    National Laboratory and at the Large Hadron Collider (LHC) at CERN near Geneva, Switzerland. This project is pursuing a microscopic understanding of the QGP properties near...

  4. LANL: AOT & LANSCE The Pulse April 2010

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    comparable precision to the Large Hadron Collider now starting operations at CERN, Switzerland. The ultracold neutron (UCN) project is an ongoing effort to measure the asymmetry...

  5. ATLAS/BNL Physicist Marc-Andre Pleier Explains the Higgs Mechanism

    ScienceCinema (OSTI)

    Pleier,Marc-Andre

    2014-06-04

    ATLAS/BNL Physicist Marc-Andre Pleier explains his role in analyzing data from the Large Hadron Collider and the search for the Higgs boson

  6. Follow the Atoms | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    the masses of data produced at the Large Hadron Collider in the quest for the Higgs boson, modeling turbulence in pursuit of improved jet engines, simulating earth's...

  7. Fermilab Today | University of Oklahoma

    Broader source: All U.S. Department of Energy (DOE) Office Webpages (Extended Search)

    - especially supersymmetry - oriented toward the physics that is starting to emerge from the Large Hadron Collider. Our theory group also works on nonperturbative quantum...

  8. Laser cooling of electron beams for linear colliders

    E-Print Network [OSTI]

    Valery Telnov

    2013-10-24

    A novel method of electron beam cooling is considered which can be used for linear colliders. The electron beam is cooled during collision with focused powerful laser pulse. With reasonable laser parameters (laser flash energy about 10 J) one can decrease transverse beam emittances by a factor about 10 per one stage. The ultimate transverse emittances are much below those achievable by other methods. Beam depolarization during cooling is about 5--15 % for one stage. This method is especially useful for photon colliders and opens new possibilities for e+e- colliders.

  9. LCFIPlus: A Framework for Jet Analysis in Linear Collider Studies

    E-Print Network [OSTI]

    Taikan Suehara; Tomohiko Tanabe

    2015-06-28

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

  10. LCFIPlus: A Framework for Jet Analysis in Linear Collider Studies

    E-Print Network [OSTI]

    Suehara, Taikan

    2015-01-01

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

  11. Effective Yukawa couplings and flavor-changing Higgs boson decays at linear colliders

    SciTech Connect (OSTI)

    Gabrielli, E.; Mele, B.

    2011-04-01

    We analyze the advantages of a linear-collider program for testing a recent theoretical proposal where the Higgs boson Yukawa couplings are radiatively generated, keeping unchanged the standard-model mechanism for electroweak-gauge-symmetry breaking. Fermion masses arise at a large energy scale through an unknown mechanism, and the standard model at the electroweak scale is regarded as an effective field theory. In this scenario, Higgs boson decays into photons and electroweak gauge-boson pairs are considerably enhanced for a light Higgs boson, which makes a signal observation at the LHC straightforward. On the other hand, the clean environment of a linear collider is required to directly probe the radiative fermionic sector of the Higgs boson couplings. Also, we show that the flavor-changing Higgs boson decays are dramatically enhanced with respect to the standard model. In particular, we find a measurable branching ratio in the range (10{sup -4}-10{sup -3}) for the decay H{yields}bs for a Higgs boson lighter than 140 GeV, depending on the high-energy scale where Yukawa couplings vanish. We present a detailed analysis of the Higgs boson production cross sections at linear colliders for interesting decay signatures, as well as branching-ratio correlations for different flavor-conserving/nonconserving fermionic decays.

  12. Design of the Proposed Low Energy Ion Collider Ring at Jefferson Lab

    SciTech Connect (OSTI)

    Nissen, Edward W.; Lin, Fanglei; Morozov, Vasiliy; Zhang, Yuhong

    2013-06-01

    The polarized Medium energy Electron-Ion Collider (MEIC) envisioned at Jefferson Lab will cover a range of center-of-mass energies up to 65 GeV. The present MEIC design could also allow the accommodation of low energy electron-ion collisions (LEIC) for additional science reach. This paper presents the first design of the low energy ion collider ring which is converted from the large ion booster of MEIC. It can reach up to 25 GeV energy for protons and equivalent ion energies of the same magnetic rigidity. An interaction region and an electron cooler designed for MEIC are integrated into the low energy collider ring, in addition to other required new elements including crab cavities and ion spin rotators, for later reuse in MEIC itself. A pair of vertical chicanes which brings the low energy ion beams to the plane of the electron ring and back to the low energy ion ring are also part of the design.

  13. Detecting Gluino-Containing Hadrons

    E-Print Network [OSTI]

    Glennys R. Farrar

    1996-03-11

    When SUSY breaking produces only dimension-2 operators, gluino and photino masses are of order 1 GeV or less. The gluon-gluino bound state has mass 1.3-2.2 GeV and lifetime > 10^{-5} - 10^{-10} s. This range of mass and lifetime is largely unconstrained because missing energy and beam dump techniques are ineffective. With only small modifications, upcoming K^0 decay experiments can study most of the interesting range. The lightest gluino-containing baryon (uds-gluino) is long-lived or stable; experiments to find it and the uud-gluino are also discussed.

  14. New Methods of Particle Collimation in Colliders

    SciTech Connect (OSTI)

    Stancari, Giulio; /Fermilab

    2011-10-01

    The collimation system is an essential part of the design of any high-power accelerator. Its functions include protection of components from accidental and intentional energy deposition, reduction of backgrounds, and beam diagnostics. Conventional multi-stage systems based on scatterers and absorbers offer robust shielding and efficient collection of losses. Two complementary concepts have been proposed to address some of the limitations of conventional systems: channeling and volume reflection in bent crystals and collimation with hollow electron beams. The main focus of this paper is the hollow electron beam collimator, a novel concept based on the interaction of the circulating beam with a 5-keV, magnetically confined, pulsed hollow electron beam in a 2-m-long section of the ring. The electrons enclose the circulating beam, kicking halo particles transversely and leaving the beam core unperturbed. By acting as a tunable diffusion enhancer and not as a hard aperture limitation, the hollow electron beam collimator extends conventional collimation systems beyond the intensity limits imposed by tolerable losses. The concept was tested experimentally at the Fermilab Tevatron proton-antiproton collider. Results on the collimation of 980-GeV antiprotons are presented, together with prospects for the future.

  15. The Next Linear Collider Klystron Development Program*

    E-Print Network [OSTI]

    E. Jongewaard; G. Caryotakis; C. Pearson; R. M. Phillips; D. Sprehn; A. Vlieks

    2000-08-19

    Klystrons capable of 75 MW output power at 11.4 GHz have been under development at SLAC for the last decade. The work has been part of the program to realize all the components necessary for the construction of the Next Linear Collider (NLC). The effort has produced a family of solenoid-focused 50 MW klystrons, which are currently powering a 0.5 GeV test accelerator at SLAC and several test stands, where high power components are evaluated and fundamental research is performed studying rf breakdown and dark current production. Continuing development has resulted in a Periodic Permanent Magnet (PPM) focused 50 MW klystron, tested at SLAC and subsequently contracted for manufacture by industry in England and Japan. A 75 MW version of that PPM klystron was built at SLAC and reached 75 MW, with 2.8 microsecond pulses. Based on this design, a prototype 75 MW klystron, designed for low-cost manufacture, is currently under development at SLAC, and will eventually be procured from industry in modest quantities for advanced NLC tests. Beyond these developments, the design of Multiple Beam Klystrons (MBKs) is under study at SLAC. MBKs offer the possibility of considerably lower modulator costs by producing comparable power to the klystrons now available, at much lower voltages. * This work supported by the Department of Energy under contract DE-AC03-76SF00515

  16. SSC 50 mm collider dipole cryostat design

    SciTech Connect (OSTI)

    Nicol, T.H.

    1992-04-01

    The cryostat of a Superconducting Super Collider (SSC) dipole magnet consists of all magnet components except the magnet assembly itself. It serves to support the magnet accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations, and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course of their expected operating life. This paper describes the design of the current SSC dipole magnet cryostat and includes discussions on the structural and thermal considerations involved in the development of each of the major systems.

  17. Cryostat design for the Superconducting Super Collider

    SciTech Connect (OSTI)

    Nicol, T.H.

    1990-09-01

    The cryostat of an SSC dipole magnet consists of all magnet components except the cold mass assembly. It serves to support the cold mass accurately and reliably within the vacuum vessel, provide all required cryogenic piping, and to insulate the cold mass from heat radiated and conducted from the environment. It must function reliably during storage, shipping and handling, normal magnet operation, quenches, and seismic excitations and must be manufacturable at low cost. The major components of the cryostat are the vacuum vessel, thermal shields, multilayer insulation (MLI) system, cryogenic piping, interconnections, and suspension system. The overall design of a cryostat for superconducting accelerator magnets requires consideration of fluid flow, proper selection of materials for their thermal and structural performance at both ambient and operating temperature, and knowledge of the environment to which the magnets will be subjected over the course their 25 year expected life. This paper describes the design of the current SSC collider dipole magnet cryostat and includes discussions on the thermal, structural, and dynamic considerations involved in the development of each of the major systems. 7 refs., 4 figs.

  18. Adaptive Finite Elements and Colliding Black Holes

    E-Print Network [OSTI]

    Douglas N. Arnold; Arup Mukherjee; Luc Pouly

    1997-09-15

    According to the theory of general relativity, the relative acceleration of masses generates gravitational radiation. Although gravitational radiation has not yet been detected, it is believed that extremely violent cosmic events, such as the collision of black holes, should generate gravity waves of sufficient amplitude to detect on earth. The massive Laser Interferometer Gravitational-wave Observatory, or LIGO, is now being constructed to detect gravity waves. Consequently there is great interest in the computer simulation of black hole collisions and similar events, based on the numerical solution of the Einstein field equations. In this note we introduce the scientific, mathematical, and computational problems and discuss the development of a computer code to solve the initial data problem for colliding black holes, a nonlinear elliptic boundary value problem posed in an unbounded three dimensional domain which is a key step in solving the full field equations. The code is based on finite elements, adaptive meshes, and a multigrid solution process. Here we will particularly emphasize the mathematical and algorithmic issues arising in the generation of adaptive tetrahedral meshes.

  19. Grid Interface Challenges and Candidate Solutions for the Compact Linear Collider’s (CLIC) Klystron Modulators

    E-Print Network [OSTI]

    Aguglia, D; Watson, A; Clare, J; Wheeler, P

    2014-01-01

    The Compact Linear Collider (CLIC) is a linear electron-positron accelerator under study at CERN, in view of exploring a new leptons collision energy region (0.5TeV to 5TeV). This complex requires ~1600 klystrons fed by highly efficient and controllable power electronics for a convenient power connection to the utility grid. This paper presents the challenges and evaluates several possible structures for the power system. Discussion are provided regarding the candidate topologies according to the converters’ ratings / number and considering reliability, modularity, and redundancy.

  20. The polarized electron beam for the SLAC Linear Collider

    E-Print Network [OSTI]

    M. Woods

    1996-11-09

    The SLAC Linear Collider has been colliding a polarized electron beam with an unpolarized positron beam at the Z^0 resonance for the SLD experiment since 1992. An electron beam polarization of close to 80% has been achieved for the experiment at luminosities up to 8x10^29 cm^-2 s^-1. This is the world's first and only linear collider, and is a successful prototype for the next generation of high energy electron linear colliders. This paper discusses polarized beam operation for the SLC, and includes aspects of the polarized source, spin transport and polarimetry. Presented at the 12th International Symposium on High Energy Spin Physics held at Amsterdam, The Netherlands September 10-14, 1996.