National Library of Energy BETA

Sample records for atlas relativistic heavy

  1. Partonic coalescence in relativistic heavy ion collisions 

    E-Print Network [OSTI]

    Greco, V.; Ko, Che Ming; Levai, P.

    2003-01-01

    Using a covariant coalescence model, we study hadron production in relativistic heavy ion collisions from both soft partons in the quark-gluon plasma and hard partons in minijets. Including transverse flow of soft partons and independent...

  2. Jets in relativistic heavy ion collisions

    SciTech Connect (OSTI)

    Wang, Xin-Nian; Gyulassy, M.

    1990-09-01

    Several aspects of hard and semihard QCD jets in relativistic heavy ion collisions are discussed, including multiproduction of minijets and the interaction of a jet with dense nuclear matter. The reduction of jet quenching effect in deconfined phase of nuclear matter is speculated to provide a signature of the formation of quark gluon plasma. HIJING Monte Carlo program which can simulate events of jets production and quenching in heavy ion collisions is briefly described. 35 refs., 13 figs.

  3. 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].

  4. Heavy flavor in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    E. L. Bratkovskaya; T. Song; H. Berrehrah; D. Cabrera; J. M. Torres-Rincon; L. Tolos; W. Cassing

    2015-08-17

    We study charm production in ultra-relativistic heavy-ion collisions by using the Parton-Hadron-String Dynamics (PHSD) transport approach. The initial charm quarks are produced by the PYTHIA event generator tuned to fit the transverse momentum spectrum and rapidity distribution of charm quarks from Fixed-Order Next-to-Leading Logarithm (FONLL) calculations. The produced charm quarks scatter in the quark-gluon plasma (QGP) with the off-shell partons whose masses and widths are given by the Dynamical Quasi-Particle Model (DQPM), which reproduces the lattice QCD equation-of-state in thermal equilibrium. The relevant cross sections are calculated in a consistent way by employing the effective propagators and couplings from the DQPM. Close to the critical energy density of the phase transition, the charm quarks are hadronized into $D$ mesons through coalescence and/or fragmentation. The hadronized $D$ mesons then interact with the various hadrons in the hadronic phase with cross sections calculated in an effective lagrangian approach with heavy-quark spin symmetry. The nuclear modification factor $R_{AA}$ and the elliptic flow $v_2$ of $D^0$ mesons from PHSD are compared with the experimental data from the STAR Collaboration for Au+Au collisions at $\\sqrt{s_{NN}}$ =200 GeV and to the ALICE data for Pb+Pb collisions at $\\sqrt{s_{NN}}$ =2.76 TeV. We find that in the PHSD the energy loss of $D$ mesons at high $p_T$ can be dominantly attributed to partonic scattering while the actual shape of $R_{AA}$ versus $p_T$ reflects the heavy-quark hadronization scenario, i.e. coalescence versus fragmentation. Also the hadronic rescattering is important for the $R_{AA}$ at low $p_T$ and enhances the $D$-meson elliptic flow $v_2$.

  5. Final Report for Project ``Theory of ultra-relativistic heavy...

    Office of Scientific and Technical Information (OSTI)

    and the stream of new high-quality data from the Relativistic Heavy Ion Collider at Brookhaven National Laboratory (which started operations in the summer of the year 2000) to...

  6. RELATIVISTIC HEAVY-ION PHYSICS WITHOUT NUCLEAR CONTACT

    E-Print Network [OSTI]

    Bertulani, Carlos A. - Department of Physics and Astronomy, Texas A&M University

    RELATIVISTIC HEAVY-ION PHYSICS WITHOUT NUCLEAR CONTACT The large electromagnetic field generated physics research--for example, for investigating nuclear structure, hadronic structure, atomic physics Berkeley Laboratory--it became clear that heavy-ion physics without nuclear contact could be very useful

  7. Heavy flavor in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Bratkovskaya, E L; Berrehrah, H; Cabrera, D; Torres-Rincon, J M; Tolos, L; Cassing, W

    2015-01-01

    We study charm production in ultra-relativistic heavy-ion collisions by using the Parton-Hadron-String Dynamics (PHSD) transport approach. The initial charm quarks are produced by the PYTHIA event generator tuned to fit the transverse momentum spectrum and rapidity distribution of charm quarks from Fixed-Order Next-to-Leading Logarithm (FONLL) calculations. The produced charm quarks scatter in the quark-gluon plasma (QGP) with the off-shell partons whose masses and widths are given by the Dynamical Quasi-Particle Model (DQPM), which reproduces the lattice QCD equation-of-state in thermal equilibrium. The relevant cross sections are calculated in a consistent way by employing the effective propagators and couplings from the DQPM. Close to the critical energy density of the phase transition, the charm quarks are hadronized into $D$ mesons through coalescence and/or fragmentation. The hadronized $D$ mesons then interact with the various hadrons in the hadronic phase with cross sections calculated in an effective...

  8. Transport Theory of Heavy Flavor in Relativistic Nuclear Collisions

    E-Print Network [OSTI]

    Cao, Shanshan

    2015-01-01

    A short overview is presented for the recent progress in the theory of heavy flavor transport in ultra-relativistic nuclear collisions, including a summary of different transport models, their phenomenological results of heavy meson quenching and flow at RHIC and LHC, a possible solution to the $R_\\mathrm{AA}$ vs. $v_2$ puzzle and predictions for heavy flavor observables beyond the current measurements.

  9. Dynamics of Ultra-Relativistic Nuclear Collisions with Heavy Beams: An Experimental Overview

    E-Print Network [OSTI]

    Peter Braun-Munzinger; Johanna Stachel

    1998-03-30

    We review, from an experimental point of view, the current status of ultra-relativistic nuclear collisions with heavy beams.

  10. Measurements of phi meson production in relativistic heavy-ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC) 

    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.; Blyth, S. -L; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bruna, E.; 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.; Chattopadhyay, 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.; Gangadharan, 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.; Heppelmann, 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, J. G.; 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.; 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.; de Toledo, 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.; Vander Molen, A. M.; Vanfossen, J. A.; Varma, R., Jr.; 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.

    2009-01-01

    REVIEW C 79, 064903 (2009) Measurements of ? meson production in relativistic heavy-ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC) B. I. Abelev,9 M. M. Aggarwal,30 Z. Ahammed,46 B. D. Anderson,19 D. Arkhipkin,13 G. S. Averichev,12 Y.... Bland,3 S.-L. Blyth,22 M. Bombara,2 B. E. Bonner,36 M. Botje,28 J. Bouchet,19 E. Braidot,28 A. V. Brandin,26 E. Bruna,51 S. Bueltmann,3 T. P. Burton,2 M. Bystersky,11 X. Z. Cai,39 H. Caines,51 M. Caldero?n de la Barca Sa?nchez,5 J. Callner,9 O. Catu,51...

  11. K+ Production in Relativistic Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Ko, Che Ming.

    1981-01-01

    VOLUME 23, NUMBER 6 E+ production in relativistic heavy-ion collisions JUNE 1981 Che Ming Ko Cydotron Institute and Physics Department, Texas AckM University, College Station, Texas 7?843 (Received 15 December 1980j Recent experimental data on K... by the temperature of the pion. The model is able to explain the data. The possibility of studying K+ yield as a signature for the pionic instability in heavy-ion collisions is indicated. NUCLEAR REACTIONS &' production, X' -7t' interaction. ? Recently...

  12. ATLAS DISCOVERY POTENTIAL FOR A HEAVY CHARGED HIGGS BOSON.

    SciTech Connect (OSTI)

    ASSAMAGAN,K.A.; COADOU,Y.; DEANDREA,A.

    2002-02-01

    The sensitivity of the ATLAS detector to the discovery of a heavy charged Higgs boson is presented. Assuming a heavy SUSY spectrum, the most promising channels above the top quark mass are H{sup {+-}} {yields} tb and h{sup {+-}} {yields} {tau}{sup {+-}}{nu}{sub {tau}} which provide coverage in the low and high tan {beta} regions up to {approx} 600 GeV. The achievable precisions on the charged Higgs mass and tan {beta} determination are also discussed. The H{sup {+-}} {yields} W{sup {+-}}h{sup 0} channel, though restricted to a small MSSM parameter space, shows a viable signal in NMSSM where the parameter space is less constrained. The observation of the channel H{sup -} {yields} {tau}{sub L}{sup -} {nu}{sub {tau}} + c.c. may constitute a distinctive evidence for models with singlet neutrinos in large extra dimensions.

  13. Quarkonium formation time in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Taesoo Song; Che Ming Ko; Su Houng Lee

    2015-02-19

    We calculate the quarkonium formation time in relativistic heavy-ion collisions from the space-time correlator of heavy quark vector currents in a hydrodynamics background with the initial nonequilibrium stage expanding only in the longitudinal direction. Using in-medium quarkonia properties determined with the heavy quark potential taken to be the free energy from lattice calculations and the fact that quarkonia can only be formed below their dissociation temperatures due to color screening, we find that $\\Upsilon$(1S), $\\Upsilon$(2S), $\\Upsilon$(3S), $J/\\psi$ and $\\psi^\\prime$ are formed, respectively, at 1.2, 6.6, 8.8, 5.8, and 11.0 fm/c after the quark pair are produced in central Au+Au collisions at the top energy of Relativistic Heavy Ion Collider (RHIC), and these times become shorter in semi-central collisions. We further show, as an example, that including the effect of formation time enhances appreciably the survivability of $\\Upsilon$(1S) in the produced hot dense matter.

  14. Realistic expanding source model for relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Chapman, S; Chapman, Scott; Nix, J Rayford

    1996-01-01

    We introduce a new realistic expanding source model for invariant one-particle multiplicity distributions and two-particle correlations in nearly central relativistic heavy-ion collisions that contains nine adjustable parameters, which are necessary and sufficient to properly characterize the gross properties of the source during its freezeout from a hydrodynamical fluid into a collection of noninteracting, free-streaming hadrons. These nine physically relevant parameters fall into three categories of three parameters each, with the first category corresponding to the source's longitudinal motion, the second category corresponding to its transverse motion, and the third category corresponding to its intrinsic properties. As an initial application, we apply our model to the analysis of invariant pi^+, pi^-, K^+, and K^- one-particle multiplicity distributions and pi^+ and K^+ two-particle correlations for nearly central Si + Au collisions at p_lab/A = 14.6 GeV/c. In a minimization with 1416 data points, the re...

  15. Observation of snake resonances at Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Bai, M.; Ahrens, L.; Alekseev, I.G.; Alessi, J.; et al

    2010-09-27

    The Siberian snakes are powerful tools in preserving polarization in high energy accelerators has been demonstrated at the Brookhaven Relativistic Heavy Ion Collider (RHIC). Equipped with two full Siberian snakes in each ring, polarization is preserved during acceleration from injection to 100 GeV. However, the Siberian snakes also introduce a new set of depolarization resonances, i.e. snake resonances as first discovered by Lee and Tepikian. The intrinsic spin resonances above 100 GeV are about a factor of two stronger than those below 100 GeV which raises the challenge to preserve the polarization up to 250 GeV. In 2009, polarized protons collided for the first time at the RHIC design store energy of 250 GeV. This paper presents the experimental measurements of snake resonances at RHIC. The plan for avoiding these resonances is also presented.

  16. MARTINI: An event generator for relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Bjoern Schenke; Charles Gale; Sangyong Jeon

    2009-10-23

    We introduce the Modular Algorithm for Relativistic Treatment of heavy IoN Interactions (MARTINI), a comprehensive event generator for the hard and penetrating probes in high energy nucleus-nucleus collisions. Its main components are a time evolution model for the soft background, PYTHIA 8.1 and the McGill-AMY parton evolution scheme including radiative as well as elastic processes. This allows us to generate full event configurations in the high p_T region that take into account thermal QCD and QED effects as well as effects of the evolving medium. We present results for the neutral pion nuclear modification factor in Au+Au collisions at RHIC as a function of p_T for different centralities, and also as a function of the angle with respect to the reaction plane for non-central collisions. Furthermore, we study the production of high transverse momentum photons incorporating a complete set of photon-production channels.

  17. Consequences of energy conservation in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    B. B. Back

    2005-08-15

    Complete characterization of particle production and emission in relativistic heavy-ion collisions is in general not feasible experimentally. This work demonstrates, however, that the availability of essentially complete pseudorapidity distributions for charged particles allows for a reliable estimate of the average transverse momenta and energy of emitted particles by requiring energy conservation in the process. The results of such an analysis for Au+Au collisions at sqrt{s_{NN}}= 130 and 200 GeV are compared with measurements of mean-p_T and mean-E_T in regions where such measurements are available. The mean-p_T dependence on pseudorapidity for Au+Au collisions at 130 and 200 GeV is given for different collision centralities.

  18. Electromagnetic Heavy Lepton Pair Production in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Sengul, M Y; Mercan, O; Karakus, N G

    2015-01-01

    We calculate the cross sections of electromagnetic productions of muon and tauon pair productions from the ultra-relativistic heavy ion collisions. Since the Compton wavelengths of muon and tauon are comparable to the radius of the colliding ions, nuclear form factors play important roles for calculating the cross sections. Recent measurement [1] indicates that the neutrons are differently distributed from the protons therefore this affects the cross section of the heavy lepton pair production. In order to see the effects of the neutron distributions in the nucleus, we used analytical expression of the Fourier transforms of the Wood-Saxon distribution. Cross section calculations show that Wood-Saxon distribution function is more sensitive to the parameter R compare to the parameter a.

  19. 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

  20. Ultra-relativistic heavy-ion physics with AFTER@LHC

    E-Print Network [OSTI]

    Rakotozafindrabe, A; Brodsky, S J; Chambert, V; Didelez, J P; Genolini, B; Ferreiro, E G; Fleuret, F; Hadjidakis, C; Lansberg, J P; Rosier, P; Schienbein, I; Scomparin, E; Uggerhoj, U I

    2012-01-01

    We outline the opportunities for ultra-relativistic heavy-ion physics which are offered by a next generation and multi-purpose fixed-target experiment exploiting the proton and ion LHC beams extracted by a bent crystal.

  1. Kaon dispersion relation and flow in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Li, Ba; Ko, Che Ming.

    1996-01-01

    Within the framework of a relativistic transport model (ART) for heavy-ion collisions at AGS energies, we examine the effects of a kaon dispersion relation on the transverse flow of kaons and their transverse momentum and ...

  2. Photons from Ultra-Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Sourav Sarkar

    2009-01-07

    It is believed that a novel state of matter - Quark Gluon Plasma (QGP) will be transiently produced if normal hadronic matter is subjected to sufficiently high temperature and/or density. We have investigated the possibility of QGP formation in the ultra-relativistic collisions of heavy ions through the electromagnetic probes - photons and dileptons. The formulation of the real and virtual photon production rate from strongly interacting matter is studied in the framework of Thermal Field Theory. Since signals from the QGP will pick up large backgrounds from hadronic matter we have performed a detailed study of the changes in the hadronic properties induced by temperature within the ambit of the Quantum Hadrodynamic model, gauged linear and non-linear sigma models, hidden local symmetry approach and QCD sum rule approach. The possibility of observing the direct thermal photons and lepton pairs from quark gluon plasma has been contrasted with that from hot hadronic matter with and without medium effects for various mass variation scenarios. The effects of medium induced modifications have also been incorporated in the evolution dynamics through the equation of state. We find that the in-medium effects on the hadronic properties in the framework of the Quantum Hadrodynamic model, Brown-Rho scaling and Nambu scaling scenarios are conspicuously visible through the low invariant mass distribution of dileptons and transverse momentum spectra of photons. We have compared our evaluation of the photon and dilepton spectra with experimental data obtained by the WA80, WA98 and CERES Collaborations in the heavy ion experiments performed at the CERN SPS. Predictions of electromagnetic spectra for RHIC energies have also been made.

  3. Partonic effects on the elliptic flow at relativistic heavy ion collisions 

    E-Print Network [OSTI]

    Lin, ZW; Ko, Che Ming.

    2002-01-01

    The elliptic flow in heavy ion collisions at the Relativistic Heavy Ion Collider is studied in a multiphase transport model. By converting the strings in the high energy density regions into partons, we find that the final elliptic flow is sensitive...

  4. Challenging the utility of third-order azimuth harmonics in the description of ultra-relativistic heavy-ion collisions

    E-Print Network [OSTI]

    R. L. Ray; D. J. Prindle; T. A. Trainor

    2013-08-20

    In recent years it has become conventional practice to include higher-order cylindrical harmonics in the phenomenological description of two-particle angular correlations from ultra-relativistic heavy-ion collisions. These model elements, whose dependence on relative azimuth angle has the form $\\cos[m(\\phi_1-\\phi_2)]$ where $m > 2$, were introduced to support a hydrodynamic flow interpretation of the same-side ($|\\phi_1-\\phi_2| 2$ harmonics are not required by the data, that they destabilize the fitting models, and that their net effect is to decompose the same-side peak into two components, one being dependent on and the other being independent of relative pseudorapidity. Thus we are lead to question whether descriptions of angular correlation data including higher-order harmonics inform our understanding of the same-side peak or heavy-ion collisions in general. Results from analysis of two-dimensional angular correlation data from the Relativistic Heavy-Ion Collider (RHIC) and the Large Hadron Collider (LHC) show that the RHIC data do not exclude a single-Gaussian hypothesis for the same-side peak. We find that the net effect of including the $m = 3$ harmonic or azimuth sextupole in the fitting model is the inclusion of small non-Gaussian dependence in the mathematical description of the same-side peak. Those non-Gaussian effects are systematically insignificant and can be accommodated by minor perturbations to the same-side 2D Gaussian peak model, which act locally at small relative azimuth. We also demonstrate that the 0-1% 2D angular correlation data for 2.76 TeV Pb+Pb collisions from ATLAS, which display an away-side double peak on azimuth, do not require a sextupole and exclude a positive same-side sextupole.

  5. Triangularity and dipole asymmetry in relativistic heavy ion collisions

    SciTech Connect (OSTI)

    Teaney, Derek; Yan Li [Department of Physics and Astronomy, Stony Brook University, Stony Brook, New York 11794-3800 (United States)

    2011-06-15

    We introduce a cumulant expansion to parametrize possible initial conditions in relativistic heavy ion collisions. We show that the cumulant expansion converges and that it can systematically reproduce the results of Glauber type initial conditions. At third order in the gradient expansion the cumulants characterize the triangularity and the dipole asymmetry of the initial entropy distribution. We show that for midperipheral collisions the orientation angle of the dipole asymmetry {psi}{sub 1,3} has a 20% preference out of plane. This leads to a small net v{sub 1} out of plane. In peripheral and midcentral collisions the orientation angles {psi}{sub 1,3} and {psi}{sub 3,3} are strongly correlated, but this correlation disappears towards central collisions. We study the ideal hydrodynamic response to these cumulants and determine the associated v{sub 1}/{epsilon}{sub 1} and v{sub 3}/{epsilon}{sub 3} for a massless ideal gas equation of state. The space time development of v{sub 1} and v{sub 3} is clarified with figures. These figures show that v{sub 1} and v{sub 3} develop toward the edge of the nucleus, and consequently the final spectra are more sensitive to the viscous dynamics of freezeout. The hydrodynamic calculations for v{sub 3} are provisionally compared to Alver and Roland fit of STAR inclusive two-particle correlation functions. Finally, we propose to measure the v{sub 1} associated with the dipole asymmetry and the correlations between {psi}{sub 1,3} and {psi}{sub 3,3} by measuring a two-particle correlation with respect to the participant plane . The hydrodynamic prediction for this correlation function is several times larger than a correlation currently measured by the STAR collaboration . This experimental measurement would provide convincing evidence for the hydrodynamic and geometric interpretation of two-particle correlations at RHIC.

  6. P(t) Dependence of Transverse Flow in Relativistic Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Li, Bao-An; Ko, Che Ming; Li, GQ.

    1996-01-01

    and th was thus informatio R(pt)[( number o ~opposite the projectil spirit to tha bevalac/si gate whethe transverse state of th heavy-ion transversel x n transverse s ~ f!# /T , ~2! azimuthal e mo- the reac- 1 /ptdpt) e flow.... It is shown that the pt e flow that is complementary to that obtained from g features of using the pt dependence to study formed in relativistic heavy-ion collisions are demon- z relativistic transport model ~ART! @15# we show that the ra- tio R(pt...

  7. 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.

  8. Physics of Ultra-Relativistic Nuclear Collisions with Heavy Beams at LHC Energy

    E-Print Network [OSTI]

    Peter Braun-Munzinger

    1999-08-18

    We discuss current plans for experiments with ultra-relativistic nuclear collisions with heavy beams at LHC energy ($\\sqrt{s} = 5.5$ TeV/nucleon pair). Emphasis will be placed on processes which are unique to the LHC program. They include event-by-event interferometry, complete spectroscopy of the $\\Upsilon$ resonances, and open charm and open beauty measurements.

  9. Low Energy Nuclear Structure from Ultra-relativistic Heavy-Light Ion collisions

    E-Print Network [OSTI]

    Enrique Ruiz Arriola; Wojciech Broniowski

    2014-11-21

    The search for specific signals in ultra-relativistic heavy-light ion collisions addressing intrinsic geometric features of nuclei may open a new window to low energy nuclear structure. We discuss specifically the phenomenon of {\\alpha}-clustering in $^{12}$C when colliding with $^{208}$Pb at almost the speed of light.

  10. Cavitation and thermal photon production in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Jitesh R. Bhatt; Hiranmaya Mishra; V. Sreekanth

    2010-11-08

    We investigate the thermal photon production-rates using one dimensional boost-invariant second order relativistic hydrodynamics to find proper time evolution of the energy density and the temperature. The effect of bulk-viscosity and non-ideal equation of state are taken into account in a manner consistent with recent lattice QCD estimates. It is shown that the \\textit{non-ideal} gas equation of state i.e $\\epsilon-3 P \

  11. 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

  12. Relativistic Heavy Ion Physics: Results from AGS to RHIC

    E-Print Network [OSTI]

    Peter Steinberg

    2002-10-04

    High-energy collisions of heavy ions provide a means to study QCD in a regime of high parton density, and may provide insight into its phase structure. Results from the four experiments at RHIC (BRAHMS, PHENIX, PHOBOS and STAR) are presented, and placed in context with the lower energy data from the AGS and SPS accelerators. The focus is on the insights these measurements provide into the time history of the collision process. Taken together, the data point to the creation of a deconfined state of matter that forms quickly, expands rapidly and freezes out suddenly.

  13. Studies of multiplicity in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    B. B. Back

    2004-11-29

    In this talk I'll review the present status of charged particle multiplicity measurements from heavy-ion collisions. The characteristic features of multiplicity distributions obtained in Au+Au collisions will be discussed in terms of collision centrality and energy and compared to those of p+p collisions. Multiplicity measurements of d+Au collisions at 200 GeV nucleon-nucleon center-of-mass energy will also be discussed. The results will be compared to various theoretical models and simple scaling properties of the data will be identified.

  14. The iEBE-VISHNU code package for relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Chun Shen; Zhi Qiu; Huichao Song; Jonah Bernhard; Steffen Bass; Ulrich Heinz

    2014-10-01

    The iEBE-VISHNU code package performs event-by-event simulations for relativistic heavy-ion collisions using viscous hydrodynamics (+ hadronic cascade model). We present the detailed model implementations accompanied with some numerical code tests for this package. The iEBE-VISHNU builds up a general theoretical framework for model-data comparisons through large scale Monte-Carlo simulations. The numerical interface between hydrodynamical evolving medium and thermal photon radiation is also discussed. This interface is designed for generic calculations of all kinds of rare probes, which are coupled to the temperature and flow velocity evolution of the bulk medium, such as jet energy loss and heavy quark diffusion.

  15. Hydro-inspired parameterizations of freeze-out in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Wojciech Florkowski; Wojciech Broniowski

    2004-10-19

    Popular parameterizations of the freeze-out conditions in relativistic heavy-ion collisions are discussed. Similarities and differences between the blast-wave model and the single-freeze-out model, both used recently to interpret the RHIC data, are outlined. A non-boost-invariant extension of the single-freeze-out model is proposed and applied to describe the recent BRAHMS data.

  16. Multi Module Modeling of Ultra-Relativistic Heavy Ion Collisions.

    SciTech Connect (OSTI)

    Magas, V. K.; Csernai, L. P.; Keranen, A.; Manninen, J.; Strottman, D. D.

    2002-01-01

    Multi Module Model is required for the realistic and detailed description of an ultrarelativistic heavy ion reaction. We are working in the framework of such a model: initial stages are described by Effective String Rope Model with expanding final streaks; hydrodynamical approach is used for the intermediate stages. This paper is mainly devoted to Third Module - the one dealing with Freeze Out (FO). Two possibilities are discussed in details: (A) freeze out at the constant time hypersurface, where the statistical production model is used to describe post FO particle species; and (B) simultaneous hadronization and freeze out from supercooled QGP. For the last case the ALCOR-like algorithm for calculation of the post FO particle species is presented, due to the fact that these do not have time to reach chemical equilibrium.

  17. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    S. V. Akkelin; Y. Hama; Iu. A. Karpenko; Yu. M. Sinyukov

    2008-08-28

    We develop a combined hydro-kinetic approach which incorporates a hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for the Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to a sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support an earlier decoupling of higher $p_{T}$ particles. By performing numerical simulations for various initial conditions and equations of state we identify several characteristic features of the bulk QCD matter evolution preferred in view of the current analysis of heavy ion collisions at RHIC energies.

  18. The B*Bpi coupling using relativistic heavy quarks

    E-Print Network [OSTI]

    J. M. Flynn; P. Fritzsch; T. Kawanai; C. Lehner; B. Samways; C. T. Sachrajda; R. S. Van de Water; O. Witzel; for the RBC/UKQCD Collaboration

    2015-06-21

    We report on a calculation of the B*Bpi coupling in lattice QCD. The strong matrix element for a B* to Bpi transition is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HMChPT) for B mesons. We carry out our calculation directly at the b-quark mass using a non-perturbatively tuned clover action that controls discretization effects of order pa and (ma)^n for all n. Our analysis is performed on RBC/UKQCD gauge configurations using domain-wall fermions and the Iwasaki gauge action at two lattice spacings of ainverse = 1.729(25) GeV, ainverse = 2.281(28) GeV, and unitary pion masses down to 290 MeV. We achieve good statistical precision and control all systematic uncertainties, giving a final result for the HMChPT coupling g_b = 0.56(3)stat(7)sys in the continuum and at the physical light-quark masses. This is the first calculation performed directly at the physical b-quark mass and lies in the region one would expect from carrying out an interpolation between previous results at the charm mass and at the static point.

  19. The B*Bpi coupling using relativistic heavy quarks

    E-Print Network [OSTI]

    Flynn, J M; Kawanai, T; Lehner, C; Samways, B; Sachrajda, C T; Van de Water, R S; Witzel, O

    2015-01-01

    We report on a calculation of the B*Bpi coupling in lattice QCD. The strong matrix element for a B* to Bpi transition is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HMChPT) for B mesons. We carry out our calculation directly at the b-quark mass using a non-perturbatively tuned clover action that controls discretization effects of order pa and (ma)^n for all n. Our analysis is performed on RBC/UKQCD gauge configurations using domain-wall fermions and the Iwasaki gauge action at two lattice spacings of ainverse = 1.729(25) GeV, ainverse = 2.281(28) GeV, and unitary pion masses down to 290 MeV. We achieve good statistical precision and control all systematic uncertainties, giving a final result for the HMChPT coupling g_b = 0.56(3)stat(7)sys in the continuum and at the physical light-quark masses. This is the first calculation performed directly at the physical b-quark mass and lies in the region one would expect from carrying out an interpolation between ...

  20. Exclusive Vector Meson Production in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Spencer Klein; Joakim Nystrand

    1999-02-06

    Exclusive vector meson production reactions such as $Au + Au \\to Au + Au + V$, where $V=\\rho, \\omega, \\phi$ or $J/\\psi$ can proceed through photon-Pomeron and photon-meson interactions. Photons from the electromagnetic field of one nucleus interact coherently with the other nucleus. Photonuclear cross sections are scaled from $\\gamma p$ data, and convoluted with the photon spectrum to find the exclusive rates. The cross sections at the RHIC and LHC heavy ion colliders are huge, 10% of the total hadronic cross section at RHIC, and 50% at LHC. These accelerators may be useful as vector meson factories. With iodine beams at RHIC, 640 $\\rho$ are produced each second (10^{10}/year); with calcium at the LHC the rate is 240 kHz. The $\\phi$ rates are 39 Hz at RHIC and 15 kHz at LHC, while the $J/\\psi$ rate is 0.3 Hz at RHIC and 780 Hz at the LHC. Because of the coherent couplings, the reactions kinematics are similar to coherent two-photon interactions; we discuss the interplay between the two reactions.

  1. The $B^*B?$ coupling with relativistic heavy quarks

    E-Print Network [OSTI]

    J. M. Flynn; P. Fritzsch; T. Kawanai; C. Lehner; C. T. Sachrajda; B. Samways; R. S. Van de Water; O. Witzel

    2013-11-10

    We report on a calculation of the $B^*B\\pi$ coupling in lattice QCD. The strong matrix element $\\langle B \\pi | B^*\\rangle$ is directly related to the leading order low-energy constant in heavy meson chiral perturbation theory (HM$\\chi$PT) for $B$-mesons. We carry out our calculation directly at the $b$-quark mass using a non-perturbatively tuned clover action that controls discretisation effects of order $|\\vec{p}a|$ and $(ma)^n$ for all $n$. Our analysis is performed on RBC/UKQCD gauge configurations using domain wall fermions and the Iwasaki gauge action at two lattice spacings of $a^{-1}=1.73(3)$ GeV, $a^{-1}=2.28(3)$ GeV, and unitary pion masses down to 290 MeV. We achieve good statistical precision and control all systematic uncertainties, giving a final result for the HM$\\chi$PT coupling $g_b = 0.569(48)_{stat}(59)_{sys}$ in the continuum and at the physical light-quark masses. This is the first calculation performed directly at the physical $b$-quark mass and lies in the region one would expect from carrying out an interpolation between previous results at the charm mass and at the static point.

  2. Partonic effects on higher-order anisotropic flows in relativistic heavy-ion collisions RID A-2398-2009 

    E-Print Network [OSTI]

    Chen, LW; Ko, Che Ming; Lin, ZW.

    2004-01-01

    Higher-order anisotropic flows v(4) and v(6) of charged hadrons in heavy-ion collisions at the Relativistic Heavy Ion Collider are studied in a multiphase transport model that has previously been used successfully for describing the elliptic flow v...

  3. Coherent Vector Meson Photoproduction with Nuclear Breakup in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Anthony J. Baltz; Spencer R. Klein; Joakim Nystrand

    2002-05-10

    Relativistic heavy ions are copious sources of virtual photons. The large photon flux gives rise to a substantial photonuclear interaction probability at impact parameters where no hadronic interactions can occur. Multiple photonuclear interactions in a single collision are possible. In this letter, we use mutual Coulomb excitation of both nuclei as a tag for moderate impact parameter collisions. We calculate the cross section for coherent vector meson production accompanied by mutual excitation, and show that the median impact parameter is much smaller than for untagged production. The vector meson rapidity and transverse momentum distribution are very different from untagged exclusive vector meson production.

  4. Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions

    E-Print Network [OSTI]

    L. V. Bravina; E. S. Fotina; V. L. Korotkikh; I. P. Lokhtin; L. V. Malinina; E. N. Nazarova; S. V. Petrushanko; A. M. Snigirev; E. E. Zabrodin

    2015-09-09

    The possible mechanisms contributing to anisotropic flow fluctuations in relativistic heavy ion collisions are discussed. The LHC data on event-by-event harmonic flow coefficients measured in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted within the HYDJET++ model. To compare the model results with the experimental data the unfolding procedure is employed. It is shown that HYDJET++ correctly reproduces dynamical fluctuations of elliptic and triangular flows and related to it eccentricity fluctuations of the initial state.

  5. Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions

    E-Print Network [OSTI]

    Bravina, L V; Korotkikh, V L; Lokhtin, I P; Malinina, L V; Nazarova, E N; Petrushanko, S V; Snigirev, A M; Zabrodin, E E

    2015-01-01

    The possible mechanisms contributing to anisotropic flow fluctuations in relativistic heavy ion collisions are discussed. The LHC data on event-by-event harmonic flow coefficients measured in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted within the HYDJET++ model. To compare the model results with the experimental data the unfolding procedure is employed. It is shown that HYDJET++ correctly reproduces dynamical fluctuations of elliptic and triangular flows and related to it eccentricity fluctuations of the initial state.

  6. Scaling properties at freeze-out in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Alekseev, I.; Alford, J.; Anderson, B. D.; Anson, C. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barnby, L. S.; Beavis, D. R.; Bellwied, R.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Borowski, W.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bridgeman, A.; Bruna, E.; Bueltmann, S.; Bunzarov, I.; Burton, T. P.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Cebra, D.; Cendejas, R.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, S.; Chen, H. F.; Chen, J. H.; Chen, J. Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Choi, K. E.; Christie, W.; Chung, P.; Codrington, M. J. M.; Corliss, R.; Cramer, J. G.; Crawford, H. J.; Dash, S.; Leyva, A. Davila; De Silva, L. C.; Debbe, R. R.; Dedovich, T. G.; Derevschikov, A. A.; Derradi de Souza, R.; Didenko, L.; Djawotho, P.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Efimov, L. G.; Elnimr, M.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Eun, L.; Evdokimov, O.; Fatemi, R.; Fedorisin, J.; Fersch, R. G.; Finch, E.; Fine, V.; Fisyak, Y.; Gagliardi, Carl A.; Gangadharan, D. R.; Ganti, M. S.; Geromitsos, A.; Geurts, F.; Ghosh, P.; Gorbunov, Y. N.; Gordon, A.; Grebenyuk, O.; Grosnick, D.; Guertin, S. M.; Gupta, A.; Guryn, W.; Haag, B.; Hamed, A.; Han, L-X; Harris, J. W.; Hays-Wehle, J. P.; Heinz, M.; Heppelmann, S.; Hirsch, A.; Hjort, E.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, B.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jena, C.; Jin, F.; Joseph, J.; Judd, E. G.; Kabana, S.; Kang, K.; Kapitan, J.; Kauder, K.; Keane, D.; Kechechyan, A.; Kettler, D.; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Kizka, V.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Kollegger, T.; Konzer, J.; Koralt, I.; Koroleva, L.; Korsch, W.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Krueger, K.; Krus, M.; Kumar, L.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; LaPointe, S.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C-H; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, L.; Li, N.; Li, W.; Li, X.; Li, X.; Li, Y.; Li, Z. M.; Lisa, M. A.; Liu, F.; Liu, H.; Liu, J.; Ljubicic, T.; Llope, W. J.; Longacre, R. S.; Love, W. A.; Lu, Y.; Lukashov, E. V.; Luo, X.; Ma, G. L.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; Mall, O. I.; Mangotra, L. K.; Manweiler, R.; Margetis, S.; Markert, C.; Masui, H.; Matis, H. S.; Matulenko, Yu A.; McDonald, D.; McShane, T. S.; Meschanin, A.; Milner, R.; Minaev, N. G.; Mioduszewski, Saskia; Mitrovski, M. K.; Mohanty, B.; Mondal, M. M.; Morozov, B.; Morozov, D. A.; Munhoz, M. G.; Naglis, M.; Nandi, B. K.; Nayak, T. K.; Netrakanti, P. K.; Ng, M. J.; Nogach, L. V.; Nurushev, S. B.; Odyniec, G.; Ogawa, A.; Ohlson, A.; Okorokov, V.; Oldag, E. W.; Olson, D.; Pachr, M.; Page, B. S.; Pal, S. K.; Pandit, Y.; Panebratsev, Y.; Pawlak, T.; Peitzmann, T.; Perkins, C.; Peryt, W.; Phatak, S. C.; Pile, P.; Planinic, M.; Ploskon, M. A.; Pluta, J.; Plyku, D.; Poljak, N.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Powell, C. B.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Pujahari, P. R.; Putschke, J.; Qiu, H.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; Reed, R.; Ritter, H. G.; Roberts, J. B.; Rogachevskiy, O. V.; Romero, J. L.; Rose, A.; Ruan, L.; Sakai, S.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Sangaline, E.; Schambach, J.; Scharenberg, R. P.; Schmah, A. M.; Schmitz, N.; Schuster, T. R.; Seele, J.; Seger, J.; Selyuzhenkov, I.; Seyboth, P.; Shahaliev, E.; Shao, M.; Sharma, M.; Shi, S. S.; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Sorensen, P.; Spinka, H. M.; Srivastava, B.; Stanislaus, T. D. S.; Staszak, D.; Stevens, J. R.; Stock, R.; 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.; Svirida, D. N.; Symons, T. J. M.; Szanto de Toledo, A.; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; Tlusty, D.; Tokarev, M.; Tram, V. N.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Leeuwen, M.; van Nieuwenhuizen, G.; Vanfossen, J. A., Jr.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Videbaek, F.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.; Walker, M.; Wang, F.; Wang, G.; Wang, H.; Wang, J. S.; Wang, Q.; Wang, X. L.; Wang, Y.; Webb, G.; Webb, J. C.; Westfall, G. D.; Whitten, C., Jr.; Wieman, H.; Wissink, S. W.; Witt, R.; Wu, Y. F.; Xie, W.; Xu, H.; Xu, N.; Xu, Q. H.; Xu, W.; Xu, Y.; Xu, Z.; Xue, L.; Yang, Y.; Yepes, P.; Yip, K.

    2011-01-01

    REVIEW C 83, 034910 (2011) Scaling properties at freeze-out in relativistic heavy-ion collisions M. M. Aggarwal,30 Z. Ahammed,22 A. V. Alakhverdyants,18 I. Alekseev,16 J. Alford,19 B. D. Anderson,19 C. D. Anson,28 D. Arkhipkin,3 G. S. Averichev,18 J.... Balewski,23 L. S. Barnby,2 D. R. Beavis,3 R. Bellwied,50 M. J. Betancourt,23 R. R. Betts,8 A. Bhasin,17 A. K. Bhati,30 H. Bichsel,49 J. Bielcik,10 J. Bielcikova,11 B. Biritz,6 L. C. Bland,3 W. Borowski,41 J. Bouchet,19 E. Braidot,27 A. V. Brandin,26 A...

  7. Ultraviolet energy dependence of particle production sources in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Georg Wolschin

    2015-01-13

    The energy dependence of particle production sources in relativistic heavy-ion collisions is investigated from RHIC to LHC energies. Whereas charged-hadron production in the fragmentation sources follows a ln(s_NN/s_0) law, particle production in the mid-rapidity gluon-gluon source exhibits a much stronger dependence proportional to ln^3(s_NN/s_0), and becomes dominant between RHIC and LHC energies. The production of particles with pseudorapidities beyond the beam rapidity is also discussed.

  8. Conference on the Intersections of Particle and Nuclear Physics 2003: Relativistic Heavy Ion Parallel Session Summary

    E-Print Network [OSTI]

    J. L. Nagle; T. Hallman

    2003-08-19

    The Relativistic Heavy Ion Collider (RHIC) came online in 2000, and the last three years have provided a wealth of new experimental data and theoretical work in this new energy frontier for nuclear physics. The transition from quarks and gluons bound into hadrons to a deconfined quark-gluon plasma is expected to occur at these energies, and the effort to understand the time evolution of these complex systems has been significantly advanced. The heavy ion parallel session talks from the Conference on the Intersections of Particle and Nuclear Physics (CIPANP) 2003 are posted at: http://www.phenix.bnl.gov/WWW/publish/nagle/CIPANP/. We provide a brief summary of these sessions here.

  9. Relativistic heavy ion collisions with realistic non-equilibrium mean fields

    E-Print Network [OSTI]

    Fuchs, C; Wolter, H H

    1996-01-01

    We study the influence of non-equilibrium phase space effects on the dynamics of heavy ion reactions within the relativistic BUU approach. We use realistic Dirac-Brueckner-Hartree-Fock (DBHF) mean fields determined for two-Fermi-ellipsoid configurations, i.e. for colliding nuclear matter, in a local phase space configuration approximation (LCA). We compare to DBHF mean fields in the local density approximation (LDA) and to the non-linear Walecka model. The results are further compared to flow data of the reaction Au on Au at 400 MeV per nucleon measured by the FOPI collaboration. We find that the DBHF fields reproduce the experiment if the configuration dependence is taken into account. This has also implications on the determination of the equation of state from heavy ion collisions.

  10. Relativistic heavy ion collisions with realistic non-equilibrium mean fields

    E-Print Network [OSTI]

    C. Fuchs; T. Gaitanos; H. H. Wolter

    1996-05-17

    We study the influence of non-equilibrium phase space effects on the dynamics of heavy ion reactions within the relativistic BUU approach. We use realistic Dirac-Brueckner-Hartree-Fock (DBHF) mean fields determined for two-Fermi-ellipsoid configurations, i.e. for colliding nuclear matter, in a local phase space configuration approximation (LCA). We compare to DBHF mean fields in the local density approximation (LDA) and to the non-linear Walecka model. The results are further compared to flow data of the reaction $Au$ on $Au$ at 400 MeV per nucleon measured by the FOPI collaboration. We find that the DBHF fields reproduce the experiment if the configuration dependence is taken into account. This has also implications on the determination of the equation of state from heavy ion collisions.

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

    SciTech Connect (OSTI)

    Fatyga, M.; Moskowitz, B.

    1990-01-01

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

  12. 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...

  13. Nonperturbative tuning of an improved relativistic heavy-quark action with application to bottom spectroscopy

    E-Print Network [OSTI]

    Yasumichi Aoki; Norman H. Christ; Jonathan M. Flynn; Taku Izubuchi; Christoph Lehner; Min Li; Hao Peng; Amarjit Soni; Ruth S. Van de Water; Oliver Witzel

    2012-06-12

    We calculate the masses of bottom mesons using an improved relativistic action for the b-quarks and the RBC/UKQCD Iwasaki gauge configurations with 2+1 flavors of dynamical domain-wall light quarks. We analyze configurations with two lattice spacings: a^{-1} = 1.729 GeV (a ~ 0.11 fm) and a^{-1} = 2.281 GeV (a ~ 0.086 fm). We use an anisotropic, clover-improved Wilson action for the b-quark, and tune the three parameters of the action nonperturbatively such that they reproduce the experimental values of the B_s and B_s* heavy-light meson states. The masses and mass-splittings of the low-lying bottomonium states (such as the eta_b and Upsilon) can then be computed with no additional inputs, and comparison between these predictions and experiment provides a test of the validity of our method. We obtain bottomonium masses with total uncertainties of ~0.5-0.6% and fine-structure splittings with uncertainties of ~35-45%; for all cases we find good agreement with experiment. The parameters of the relativistic heavy-quark action tuned for b-quarks presented in this work can be used for precise calculations of weak matrix elements such as B-meson decay constants and mixing parameters with lattice discretization errors that are of the same size as in light pseudoscalar meson quantities. This general method can also be used for charmed meson masses and matrix elements if the parameters of the heavy-quark action are appropriately tuned.

  14. Hanbury-Brown-Twiss Interferometry with Identical Bosons in Relativistic Heavy Ion Collisions: Comparisons with Hadronic Scattering Models

    E-Print Network [OSTI]

    Thomas J. Humanic

    2005-10-17

    Identical boson Hanbury-Brown-Twiss interferometry as applied to relativistic heavy-ion collisions is reviewed. Emphasis is placed on the use of hadronic scattering models to interpret the physical significance of experimental results. Interferometric studies with center-of-mass energies from < 1 GeV/nucleon up to 5500 GeV/nucleon are considered.

  15. Quark-gluon plasma in the early Universe and in ultra-relativistic heavy-ion collisions

    SciTech Connect (OSTI)

    Greco, V.

    2014-05-09

    We briefly give an elementary introduction to the expansion of the Early Universe till when the phase transition of the quark-gluon plasma to a hadronic matter takes place. Then we describe some main element of the study of QGP by mean of ultra-relativistic heavy-ion collisions (uRHIC's)

  16. 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.

  17. Fluctuations of conserved charges in relativistic heavy ion collisions: An introduction

    E-Print Network [OSTI]

    Masayuki Asakawa; Masakiyo Kitazawa

    2015-12-16

    Bulk fluctuations of conserved charges measured by event-by-event analysis in relativistic heavy ion collisions are observables which are believed to carry significant information on the primordial thermodynamics of the hot medium created by the collisions. Active studies have been done recently experimentally, theoretically, and on the lattice. In particular, non-Gaussianity of the fluctuations aquires much attention recently. In this review, we give a pedagogical introduction to these physics, and overview recent developments in this field of research. Starting from the definition of cumulants, basic concepts in fluctuation physics, such as thermal fluctuations in statistical mechanics and time evolution of fluctuations in diffusive systems, are described. Physics which are expected to occur in the QCD phase diagram and their measurement by event-by-event analyses are also elucidated.

  18. Constraints on models for the initial collision geometry in ultra relativistic heavy ion collisions

    E-Print Network [OSTI]

    Roy A. Lacey; Rui Wei; N. N. Ajitanand; J. M. Alexander; X. Gong; J. Jia; A. Taranenko; R. Pak; Horst Stocker

    2010-05-21

    Monte Carlo (MC) simulations are used to compute the centrality dependence of the collision zone eccentricities ($\\epsilon_{2,4}$), for both spherical and deformed ground state nuclei, for different model scenarios. Sizable model dependent differences are observed. They indicate that measurements of the $2^{\\text{nd}}$ and $4^{\\text{th}}$ order Fourier flow coefficients $v_{2,4}$, expressed as the ratio $\\frac{v_4}{(v_2)^2}$, can provide robust constraints for distinguishing between different theoretical models for the initial-state eccentricity. Such constraints could remove one of the largest impediments to a more precise determination of the specific viscosity from precision $v_{2,4}$ measurements at the Relativistic Heavy Ion Collider (RHIC).

  19. Initialization of hydrodynamics in relativistic heavy ion collisions with an energy-momentum transport model

    E-Print Network [OSTI]

    V. Yu. Naboka; S. V. Akkelin; Iu. A. Karpenko; Yu. M. Sinyukov

    2015-01-14

    A key ingredient of hydrodynamical modeling of relativistic heavy ion collisions is thermal initial conditions, an input that is the consequence of a pre-thermal dynamics which is not completely understood yet. In the paper we employ a recently developed energy-momentum transport model of the pre-thermal stage to study influence of the alternative initial states in nucleus-nucleus collisions on flow and energy density distributions of the matter at the starting time of hydrodynamics. In particular, the dependence of the results on isotropic and anisotropic initial states is analyzed. It is found that at the thermalization time the transverse flow is larger and the maximal energy density is higher for the longitudinally squeezed initial momentum distributions. The results are also sensitive to the relaxation time parameter, equation of state at the thermalization time, and transverse profile of initial energy density distribution: Gaussian approximation, Glauber Monte Carlo profiles, etc. Also, test results ensure that the numerical code based on the energy-momentum transport model is capable of providing both averaged and fluctuating initial conditions for the hydrodynamic simulations of relativistic nuclear collisions.

  20. ATLAS

    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 Room News Publications Traditional Knowledge Kiosks Barrow,ARM: ThreeATHENA could reduce ATLAS

  1. ?b ? p?¯?¯? and ?b ? ?c?¯?¯? form factors from lattice QCD with relativistic heavy quarks

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

    Detmold, William; Lehner, Christoph; Meinel, Stefan

    2015-08-04

    Measurements of the ?b ? p?¯?¯? and ?b ? ?c?¯?¯? decay rates can be used to determine the magnitudes of the Cabibbo-Kobayashi-Maskawa matrix elements Vub and Vcb, provided that the relevant hadronic form factors are known. Here we present a precise calculation of these form factors using lattice QCD with 2+1 flavors of dynamical domain-wall fermions. The b and c quarks are implemented with relativistic heavy-quark actions, allowing us to work directly at the physical heavy-quark masses. The lattice computation is performed for six different pion masses and two different lattice spacings, using gauge-field configurations generated by the RBC andmore »UKQCD Collaborations. The b ? u and b ? c currents are renormalized with a mostly nonperturbative method. We extrapolate the form factor results to the physical pion mass and the continuum limit, parametrizing the q² dependence using z expansions. The form factors are presented in such a way as to enable the correlated propagation of both statistical and systematic uncertainties into derived quantities such as differential decay rates and asymmetries. Using these form factors, we present predictions for the ?b ? p?¯?¯? and ?b ? ?c?¯?¯?differential and integrated decay rates. Combined with experimental data, our results enable determinations of |Vub|, |Vcb|, and |Vub/Vcb| with theory uncertainties of 4.4%, 2.2%, and 4.9%, respectively.« less

  2. ?????????? ??????? ????????, ???????? ? ???????????? ?????????? ????????? ????????? ??????????? ????????? ? ???????????? ATLAS (????)

    E-Print Network [OSTI]

    Mashinistov, Ruslan

    2011-01-01

    The thesis is devoted to research, analysis, development and implementation of software for the detector monitoring, for database tools and also for recorded data quality control of the ATLAS Transition Radiation Tracker (TRT). The TRT is the outermost of the three sub-systems of the ATLAS inner tracking detector at the Large Hadron Collider (LHC) at CERN and is one of the important tools to reconstruct tracks of charged particles and to identify the particle species. TRT contains more than 350,000 channels of information and reading more than 22600 units of electronics. The TRT consists of thin proportional chambers either in the form of straws embedded in fibers or with foils and straws in separate layers. Straws are providing the registration the time and amplitude parameters of a signal. Readout electronics set two independent thresholds to cut the noises and separate the transition radiation events. Different effects and conditions as synchronization of a time parameters of the detector and LHC are influ...

  3. Search for type-III seesaw heavy leptons in pp collisions at s=8 TeVwith the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O. S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-08-03

    A search for the pair production of heavy leptons (N?,L±) predicted by the type-III seesaw theory formulated to explain the origin of small neutrino masses is presented. The decay channels N??W±l? (?=e,?,?) and L±?W±? (?=?e,??,??) are considered. The analysis is performed using the final state that contains two leptons (electrons or muons), two jets from a hadronically decaying W boson and large missing transverse momentum. The data used in the measurement correspond to an integrated luminosity of 20.3 fb?¹ of pp collisions at s?=8 TeV collected by the ATLAS detector at the LHC. No evidence of heavy lepton pair productionmore »is observed. Heavy leptons with masses below 325–540 GeV are excluded at the 95% confidence level, depending on the theoretical scenario considered.« less

  4. Search for type-III seesaw heavy leptons inppcollisions ats=8 TeVwith the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdinov, O.; Aben, R.; Abolins, M.; AbouZeid, O.?S.; Abramowicz, H.; Abreu, H.; Abreu, R.; et al

    2015-08-01

    A search for the pair production of heavy leptons (N?,L±) predicted by the type-III seesaw theory formulated to explain the origin of small neutrino masses is presented. The decay channels N??W±l? (?=e,?,?) and L±?W±? (?=?e,??,??) are considered. The analysis is performed using the final state that contains two leptons (electrons or muons), two jets from a hadronically decaying W boson and large missing transverse momentum. The data used in the measurement correspond to an integrated luminosity of 20.3??fb?¹ of pp collisions at s?=8??TeV collected by the ATLAS detector at the LHC. No evidence of heavy lepton pair production is observed.more »Heavy leptons with masses below 325–540 GeV are excluded at the 95% confidence level, depending on the theoretical scenario considered.« less

  5. Identification and Rejection of Fake Reconstructed Jets From a Fluctuating Heavy Ion Background in ATLAS

    E-Print Network [OSTI]

    N. Grau; B. A. Cole; W. G. Holzmann; M. Spousta; P. Steinberg

    2008-10-07

    Full jet reconstruction in relativistic heavy ion collisions provides new and unique insights to the physics of parton energy loss. Because of the large underlying event multiplicity in $A+A$ collisions, random and correlated fluctuations in the background can result in the reconstruction of fake jets. These fake jets must be identified and rejected to obtain the purest jet sample possible. A large but reducible fake rate of jets reconstructed using an iterative cone algorithm on HIJING events is observed. The absolute rate of fake jets exceeds the binary-scaled p+p jet rate below 50 GeV and is not negligible until 100 GeV. The variable $\\Sigma j_{T}$, the sum of the jet constituent's $E_{T}$ perpendicular to the jet axis, is introduced to identify and reject fake jets at by a factor of 100 making it negligible. This variable is shown to not strongly depend on jet energy profiles modified by energy loss. By studying azimuthal correlations of reconstructed di-jets, the fake jet rate can be evaluated in data.

  6. The study of background electric field in relativistic heavy-ion collisions in the RHIC and LHC energy regions

    E-Print Network [OSTI]

    Zhong, Yang; Cai, Xu; Feng, Sheng-Qin

    2015-01-01

    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. Based on the theory of Kharzeev, McLerran, and Warringa, we used the Wood-Saxon nucleon distribution to replace that of the uniform distribution to improve the electric field calculation method of the off-central collision. The chiral electro field 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.

  7. Operational head-on beam-beam compensation with electron lenses in the Relativistic Heavy Ion Collider

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

    Fischer, W.; Gu, X.; Altinbas, Z.; Costanzo, M.; Hock, J.; Liu, C.; Luo, Y.; Marusic, A.; Michnoff, R.; Miller, T. A.; et al

    2015-12-23

    Head-on beam-beam compensation has been implemented in the Relativistic Heavy Ion Collider (RHIC) in order to increase the luminosity delivered to the experiments. We discuss the principle of combining a lattice for resonance driving term compensation and an electron lens for tune spread compensation. We describe the electron lens technology and its operational use. As of this date the implemented compensation scheme approximately doubled the peak and average luminosities.

  8. Search for heavy Majorana neutrinos with the ATLAS detector in pp collisions at ?s = 8 TeV

    SciTech Connect (OSTI)

    Aad, G.

    2015-07-29

    A search for heavy Majorana neutrinos in events containing a pair of high-pT leptons of the same charge and high-pT jets is presented. The search uses 20.3 fb-1 of pp collision data collected with the ATLAS detector at the CERN Large Hadron Collider with a centre-of-mass energy of ?s = 8 TeV. The data are found to be consistent with the background-only hypothesis based on the Standard Model expectation. In the context of a Type-I seesaw mechanism, limits are set on the production cross-section times branching ratio for production of heavy Majorana neutrinos in the mass range between 100 and 500 GeV. The limits are subsequently interpreted as limits on the mixing between the heavy Majorana neutrinos and the Standard Model neutrinos. In the context of a left-right symmetric model, limits on the production cross-section times branching ratio are set with respect to the masses of heavy Majorana neutrinos and heavy gauge bosons WR and Z'.

  9. Search for heavy Majorana neutrinos with the ATLAS detector in pp collisions at ?s = 8 TeV

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

    Aad, G.; et al.

    2015-07-29

    A search for heavy Majorana neutrinos in events containing a pair of high-pT leptons of the same charge and high-pT jets is presented. The search uses 20.3 fb-1 of pp collision data collected with the ATLAS detector at the CERN Large Hadron Collider with a centre-of-mass energy of ?s = 8 TeV. The data are found to be consistent with the background-only hypothesis based on the Standard Model expectation. In the context of a Type-I seesaw mechanism, limits are set on the production cross-section times branching ratio for production of heavy Majorana neutrinos in the mass range between 100 andmore »500 GeV. The limits are subsequently interpreted as limits on the mixing between the heavy Majorana neutrinos and the Standard Model neutrinos. In the context of a left-right symmetric model, limits on the production cross-section times branching ratio are set with respect to the masses of heavy Majorana neutrinos and heavy gauge bosons WR and Z'.« less

  10. Search for heavy Majorana neutrinos with the ATLAS detector in pp collisions at $\\sqrt{s} = 8$ TeV

    E-Print Network [OSTI]

    Aad, Georges; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Almond, John; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Arabidze, Giorgi; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, Bradley; Ayoub, Mohamad Kassem; Azuelos, Georges; Baak, Max; Baas, Alessandra; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Balek, Petr; Balestri, Thomas; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Bansil, Hardeep Singh; Barak, Liron; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Bauce, Matteo; Bauer, Florian; Bawa, Harinder Singh; Beacham, James Baker; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Janna Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bender, Michael; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Beresford, Lydia; Beretta, Matteo; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Beringer, Jürg; Bernard, Clare; Bernard, Nathan Rogers; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertsche, Carolyn; Bertsche, David; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia Bylund, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bevan, Adrian John; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien; Bingul, Ahmet; Bini, Cesare; Black, Curtis; Black, James

    2015-01-01

    A search for heavy Majorana neutrinos in events containing a pair of high-$p_{\\mathrm{T}}$ leptons of the same charge and high-$p_{\\mathrm{T}}$ jets is presented. The search uses $20.3 \\mathrm{fb}^{-1}$ of $pp$ collision data collected with the ATLAS detector at the CERN Large Hadron Collider with a centre-of-mass energy of $\\sqrt{s} = 8$ TeV. The data are found to be consistent with the background-only hypothesis based on the Standard Model expectation. In the context of a Type-I seesaw mechanism, limits are set on the production cross-section times branching ratio for production of heavy Majorana neutrinos in the mass range between 100 and 500 GeV. The limits are subsequently interpreted as limits on the mixing between the heavy Majorana neutrinos and the Standard Model neutrinos. In the context of a left-right symmetric model, limits on the production cross-section times branching ratio are set with respect to the masses of heavy Majorana neutrinos and heavy gauge bosons $W_{\\mathrm{R}}$ and $Z'$.

  11. Optics measurement and correction during beam acceleration in the Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Liu, C.; Marusic, A.; Minty, M.

    2014-09-09

    To minimize operational complexities, setup of collisions in high energy circular colliders typically involves acceleration with near constant ?-functions followed by application of strong focusing quadrupoles at the interaction points (IPs) for the final beta-squeeze. At the Relativistic Heavy Ion Collider (RHIC) beam acceleration and optics squeeze are performed simultaneously. In the past, beam optics correction at RHIC has taken place at injection and at final energy with some interpolation of corrections into the acceleration cycle. Recent measurements of the beam optics during acceleration and squeeze have evidenced significant beta-beats which if corrected could minimize undesirable emittance dilutions and maximize the spin polarization of polarized proton beams by avoidance of higher-order multipole fields sampled by particles within the bunch. In this report the methodology now operational at RHIC for beam optics corrections during acceleration with simultaneous beta-squeeze will be presented together with measurements which conclusively demonstrate the superior beam control. As a valuable by-product, the corrections have minimized the beta-beat at the profile monitors so reducing the dominant error in and providing more precise measurements of the evolution of the beam emittances during acceleration.

  12. (3+1)D hydrodynamic simulation of relativistic heavy-ion collisions

    SciTech Connect (OSTI)

    Schenke, Bjoern; Jeon, Sangyong; Gale, Charles

    2010-07-15

    We present music, an implementation of the Kurganov-Tadmor algorithm for relativistic 3+1 dimensional fluid dynamics in heavy-ion collision scenarios. This Riemann-solver-free, second-order, high-resolution scheme is characterized by a very small numerical viscosity and its ability to treat shocks and discontinuities very well. We also incorporate a sophisticated algorithm for the determination of the freeze-out surface using a three dimensional triangulation of the hypersurface. Implementing a recent lattice based equation of state, we compute p{sub T}-spectra and pseudorapidity distributions for Au+Au collisions at sq root(s)=200 GeV and present results for the anisotropic flow coefficients v{sub 2} and v{sub 4} as a function of both p{sub T} and pseudorapidity eta. We were able to determine v{sub 4} with high numerical precision, finding that it does not strongly depend on the choice of initial condition or equation of state.

  13. Two-Photon Interactions with Nuclear Breakup in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Anthony J. Baltz; Yuri Gorbunov; Spencer R. Klein; Joakim Nystrand

    2009-08-26

    Highly charged relativistic heavy ions have high cross-sections for two-photon interactions. The photon flux is high enough that two-photon interactions may be accompanied by additional photonuclear interactions. Except for the shared impact parameter, these interactions are independent. Additional interactions like mutual Coulomb excitation are of experimental interest, since the neutrons from the nuclear dissociation provide a simple, relatively unbiased trigger. We calculate the cross sections, rapidity, mass and transverse momentum ($p_T)$ distributions for exclusive $\\gamma\\gamma$ production of mesons and lepton pairs, and for $\\gamma\\gamma$ reactions accompanied by mutual Coulomb dissociation. The cross-sections for $\\gamma\\gamma$ interactions accompanied by multiple neutron emission ($XnXn$) and single neutron emission ($1n1n$) are about 1/10 and 1/100 of that for the unaccompanied $\\gamma\\gamma$ interactions. We discuss the accuracy with which these cross-sections may be calculated. The typical $p_T$ of $\\gamma\\gamma$ final states is several times smaller than for comparable coherent photonuclear interactions, so $p_T$ may be an effective tool for separating the two classes of interactions.

  14. Two-photon interactions with nuclear breakup in relativistic heavy ion collisions

    SciTech Connect (OSTI)

    Baltz, Anthony J.; Gorbunov, Yuri; Klein, Spencer R.; Nystrand, Joakim

    2009-10-15

    Highly charged relativistic heavy ions have high cross sections for two-photon interactions. The photon flux is high enough that two-photon interactions may be accompanied by additional photonuclear interactions. Except for the shared impact parameter, these interactions are independent. Additional interactions like mutual Coulomb excitation are of experimental interest, because the neutrons from the nuclear dissociation provide a simple, relatively unbiased trigger. We calculate the cross sections, rapidity, mass, and transverse momentum (p{sub T}) distributions for exclusive {gamma}{gamma} production of mesons and lepton pairs and for {gamma}{gamma} reactions accompanied by mutual Coulomb dissociation. The cross sections for {gamma}{gamma} interactions accompanied by multiple neutron emission (XnXn) and single-neutron emission (1n1n) are about 1/10 and 1/100 of that for the unaccompanied {gamma}{gamma} interactions. We discuss the accuracy with which these cross sections may be calculated. The typical p{sub T} of {gamma}{gamma} final states is several times smaller than for comparable coherent photonuclear interactions, so p{sub T} may be an effective tool for separating the two classes of interactions.

  15. Two-Photon Interactions with Nuclear Breakup in Relativistic Heavy Ion Collisions

    SciTech Connect (OSTI)

    Baltz, Anthony J.; Gorbunov, Yuri; R Klein, Spencer; Nystrand, Joakim

    2010-07-07

    Highly charged relativistic heavy ions have high cross-sections for two-photon interactions. The photon flux is high enough that two-photon interactions may be accompanied by additional photonuclear interactions. Except for the shared impact parameter, these interactions are independent. Additional interactions like mutual Coulomb excitation are of experimental interest, since the neutrons from the nuclear dissociation provide a simple, relatively unbiased trigger. We calculate the cross sections, rapidity, mass and transverse momentum (p{sub T}) distributions for exclusive {gamma}{gamma} production of mesons and lepton pairs, and for {gamma}{gamma} reactions accompanied by mutual Coulomb dissociation. The cross-sections for {gamma}{gamma} interactions accompanied by multiple neutron emission (XnXn) and single neutron emission (1n1n) are about 1/10 and 1/100 of that for the unaccompanied {gamma}{gamma} interactions. We discuss the accuracy with which these cross-sections may be calculated. The typical p{sub T} of {gamma}{gamma} final states is several times smaller than for comparable coherent photonuclear interactions, so p{sub T} may be an effective tool for separating the two classes of interactions.

  16. Alternative Scenarios of Relativistic Heavy-Ion Collisions: II. Particle Production

    E-Print Network [OSTI]

    Yu. B. Ivanov

    2013-06-04

    Particle production in relativistic collisions of heavy nuclei is analyzed in a wide range of incident energies 2.7 GeV $\\le \\sqrt{s_{NN}}\\le$ 62.4 GeV. The analysis is performed within the three-fluid model employing three different equations of state (EoS): a purely hadronic EoS, an EoS with the first-order phase transition and that with a smooth crossover transition. It is found that the hadronic scenario fails to reproduce experimental yields of antibaryons (strange and nonstrange), starting already from lower SPS energies, i.e. $\\sqrt{s_{NN}}>$ 5 GeV. Moreover, at energies above the top SPS one, i.e. $\\sqrt{s_{NN}}>$ 17.4 GeV, the mid-rapidity densities predicted by the hadronic scenario considerably exceed the available RHIC data on all species. At the same time the deconfinement-transition scenarios reasonably agree (to a various extent) with all the data. The present analysis demonstrates certain advantage of the deconfinement-transition EoS's. However, all scenarios fail to reproduce the strangeness enhancement in the incident energy range near 30A GeV (i.e. a horn anomaly in the $K^+/\\pi^+$ ratio) and yields of $\\phi$-mesons at 20A--40A GeV.

  17. Alternative Scenarios of Relativistic Heavy-Ion Collisions: I. Baryon Stopping

    E-Print Network [OSTI]

    Yu. B. Ivanov

    2013-02-23

    Simulations of relativistic heavy-ion collisions within the three-fluid model employing a purely hadronic equation of state (EoS) and two versions of the EoS involving deconfinement transition are presented. The latter are an EoS with the first-order phase transition and that with a smooth crossover transition. The model setup is described in detail. The analysis is performed in a wide range of incident energies 2.7 GeV $< \\sqrt{s_{NN}} <$ 39 GeV in terms of the center-of-mass energy. Results on proton and net-proton rapidity distributions are reported. Comparison with available data indicate certain preference of the crossover EoS. It is found that predictions within deconfinement-transition scenarios exhibit a "peak-dip-peak-dip" irregularity in the incident energy dependence of the form of the net-proton rapidity distributions in central collisions. This irregularity is a signal of deconfinement onset occurring in the hot and dense stage of the nuclear collision.

  18. Search for a Heavy Particle Decaying into an Electron and a Muon with the ATLAS Detector in ?s=7??TeV pp collisions at the LHC

    E-Print Network [OSTI]

    Taylor, Frank E.

    This Letter presents the first search for a heavy particle decaying into an e[superscript ±]?[superscript ?] final state in ?s=7??TeV pp collisions at the LHC. The data were recorded by the ATLAS detector during 2010 and ...

  19. 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...

  20. K-*(892)(0) production in relativistic heavy ion collisions at root s(NN)=130 GeV 

    E-Print Network [OSTI]

    Adler, C.; Ahammed, Z.; Allgower, C.; Amonett, J.; Anderson, BD; Anderson, M.; Averichev, GS; Balewski, J.; Barannikova, O.; Barnby, LS; Baudot, J.; Bekele, S.; Belaga, VV; Bellwied, R.; Berger, J.; Bichsel, H.; Billmeier, A.; Bland, LC; Blyth, CO; Bonner, BE; Boucham, A.; Brandin, A.; Bravar, A.; Cadman, RV; Caines, H.; Sanchez, MCD; Cardenas, A.; Carroll, J.; Castillo, J.; Castro, M.; Cebra, D.; Chaloupka, P.; Chattopadhyay, S.; Chen, Y.; Chernenko, SP; Cherney, M.; Chikanian, A.; Choi, B.; Christie, W.; Coffin, JP; Cormier, TM; Cramer, JG; Crawford, HJ; Derevschikov, AA; Didenko, L.; Dietel, T.; Draper, JE; Dunin, VB; Dunlop, JC; Eckardt, V.; Efimov, LG; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Fachini, P.; Faine, V.; Faivre, J.; Fatemi, R.; Filimonov, K.; Finch, E.; Fisyak, Y.; Flierl, D.; Foley, KJ; Fu, J.; Gagliardi, Carl A.; Gagunashvili, N.; Gans, J.; Gaudichet, L.; Germain, M.; Geurts, F.; Ghazikhanian, V.; Grachov, O.; Grigoriev, V.; Guedon, M.; Gushin, E.; Hallman, TJ; Hardtke, D.; Harris, JW; Henry, TW; Heppelmann, S.; Herston, T.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, GW; Horsley, M.; Huang, HZ; Humanic, TJ; Igo, G.; Ishihara, A.; Ivanshin, YI; Jacobs, P.; Jacobs, WW; Janik, M.; Johnson, I.; Jones, PG; Judd, EG; Kaneta, M.; Kaplan, M.; Keane, D.; Kiryluk, J.; Kisiel, A.; Klay, J.; Klein, SR; Klyachko, A.; Kollegger, T.; Konstantinov, AS; Kopytine, M.; Kotchenda, L.; Kovalenko, AD; Kramer, M.; Kravtsov, P.; Krueger, K.; Kuhn, C.; Kulikov, AI; Kunde, GJ; Kunz, CL; Kutuev, RK; Kuznetsov, AA; Lakehal-Ayat, L.; Lamont, MAC; Landgraf, JM; Lange, S.; Lansdell, CP; Lasiuk, B.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Leontiev, VM; LeVine, MJ; Li, Q.; Lindenbaum, SJ; Lisa, MA; Liu, F.; Liu, L.; Liu, Z.; Liu, QJ; Ljubicic, T.; Llope, WJ; LoCurto, G.; Long, H.; Longacre, RS; Lopez-Noriega, M.; Love, WA; Ludlam, T.; Lynn, D.; Ma, J.; Majka, R.; Margetis, S.; Markert, C.; Martin, L.; Marx, J.; Matis, HS; Matulenko, YA; McShane, TS; Meissner, F.; Melnick, Y.; Meschanin, A.; Messer, M.; Miller, ML; Milosevich, Z.; Minaev, NG; Mitchell, J.; Moore, CF; Morozov, V.; de Moura, MM; Munhoz, MG; Nelson, JM; Nevski, P.; Nikitin, VA; Nogach, LV; Norman, B.; Nurushev, SB; Odyniec, G.; Ogawa, A.; Okorokov, V.; Oldenburg, M.; Olson, D.; Paic, G.; Pandey, SU; Panebratsev, Y.; Panitkin, SY; Pavlinov, AI; Pawlak, T.; Perevoztchikov, V.; Peryt, W.; Petrov, VA; Planinic, M.; Pluta, J.; Porile, N.; Porter, J.; Poskanzer, AM; Potrebenikova, E.; Prindle, D.; Pruneau, C.; Putschke, J.; Rai, G.; Rakness, G.; Ravel, O.; Ray, RL; Razin, SV; Reichhold, D.; Reid, JG; Renault, G.; Retiere, F.; Ridiger, A.; Ritter, HG; Roberts, JB; Rogachevski, OV; Romero, JL; Rose, A.; Roy, C.; Rykov, V.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Savin, I.; Schambach, J.; Scharenberg, RP; Schmitz, N.; Schroeder, LS; Schuttauf, A.; Schweda, K.; Seger, J.; Seliverstov, D.; Seyboth, P.; Shahaliev, E.; Shestermanov, KE; Shimanskii, SS; Skoro, G.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; Stephenson, EJ; Stock, R.; Stolpovsky, A.; Strikhanov, M.; Stringfellow, B.; Struck, C.; Suaide, AAP; Sugarbaker, E.; Suire, C.; Sumbera, M.; Surrow, B.; Symons, TJM; de Toledo, AS; Szarwas, P.; Tai, A.; Takahashi, J.; Tang, AH; Thein, D.; Thomas, JH; Thompson, M.; Tikhomirov, V.; Tokarev, M.; Tonjes, MB; Trainor, TA; Trentalange, S.; Tribble, Robert E.; Trofimov, V.; Tsai, O.; Ullrich, T.; Underwood, DG; Van Buren, G.; VanderMolen, AM; Vasilevski, IM; Vasiliev, AN; Vigdor, SE; Voloshin, SA; Wang, F.; Ward, H.; Watson, JW; Wells, R.; Westfall, GD; Whitten, C.; Wieman, H.; Willson, R.; Wissink, SW; Witt, R.; Wood, J.; Xu, N.; Xu, Z.; Yakutin, AE; Yamamoto, E.; Yang, J.; Yepes, P.; Yurevich, VI; Zanevski, YV; Zborovsky, I.; Zhang, H.; Zhang, WM; Zoulkarneev, R.; Zubarev, AN; STAR Collaboration.

    2002-01-01

    COMMUNICATIONS PHYSICAL REVIEW C 66, 061901~R! ~2002! K*?892?0 production in relativistic heavy ion collisions at AsNN?130 GeV C. Adler,11 Z. Ahammed,23 C. Allgower,12 J. Amonett,14 B. D. Anderson,14 M. Anderson,5 G. S. Averichev,9 J. Balewski,12 O.... Barannikova,9,23 L. S. Barnby,14 J. Baudot,13 S. Bekele,20 V. V. Belaga,9 R. Bellwied,31 J. Berger,11 H. Bichsel,30 A. Billmeier,31 L. C. Bland,2 C. O. Blyth,3 B. E. Bonner,24 A. Boucham,26 A. Brandin,18 A. Bravar,2 R. V. Cadman,1 H. Caines,33 M. Caldero...

  1. rho(0) photoproduction in ultraperipheral relativistic heavy ion collisions at root s(NN)=200 GeV 

    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.; Bland, L. C.; Blyth, S. -L; Bombara, M.; Bonner, B. E.; Botje, M.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bueltmann, S.; Burton, T. P.; Bystersky, M.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; Callner, J.; Catu, O.; Cebra, D.; Cervantes, M. C.; Chajecki, Z.; Chaloupka, P.; Chattopadhyay, 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 Moura, M. M.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; de Souza, R. Derradi; Didenko, L.; Dietel, T.; 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.; 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.; Fu, J.; Gagliardi, Carl A.; Gaillard, L.; 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.; Henry, T. W.; Hepplemann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Horner, M. J.; Huang, H. Z.; Hughes, E. W.; Humanic, T. J.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jin, F.; Jones, P. G.; 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.; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kouchpil, V.; Kowalik, K. L.; Kravtsov, P.; Kravtsov, V. I.; Krueger, K.; Kuhn, C.; Kumar, A.; Kurnadi, P.; Lamont, M. A. C.; Landgraf, J. M.; Lange, S.; LaPointe, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lee, C. -H; LeVine, M. J.; Li, C.; Li, Q.; 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, J. G.; Ma, Y. G.; Mahapatra, D. P.; Majka, R.; 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.; 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.; Pal, S. K.; Panebratsev, Y.; Pavlinov, A. I.; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Phatak, S. C.; Planinic, M.; Pluta, J.; Poljak, N.; Porile, N.; Poskanzer, A. M.; Potekhin, M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Putschke, J.; Qattan, I. A.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Relyea, D.; 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, X. -H; Sichtermann, E. P.; Simon, F.; Singaraju, R. N.; Skoby, M. J.; Smirnov, N.; Snellings, R.; Sorensen, P.; Sowinski, J.; Speltz, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, T. D. S.; Staszak, D.; Stock, R.; Strikhanov, M.; Stringfellow, B.; Suaide, A. A. P.; Suarez, M. C.; Subba, N. L.; Sumbera, M.; Sun, X. M.; Sun, Z.; Surrow, B.; Symons, T. J. M.; de Toledo, A. Szanto; Takahashi, J.; Tang, A. H.; Tang, Z.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; 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 der Kolk, N.; van Leeuwen, M.; Molen, A. M. Vander; Varma, R.; Vasconcelos, G. M. S.; Vasilevski, I. M.; Vasiliev, A. N.; Vernet, R.; Videbaek, F.; Vigdor, S. E.; Viyogi, Y. P.; Vokal, S.

    2008-01-01

    REVIEW C 77, 034910 (2008) ?0 photoproduction in ultraperipheral relativistic heavy ion collisions at?sNN = 200 GeV B. I. Abelev,10 M. M. Aggarwal,32 Z. Ahammed,47 B. D. Anderson,21 D. Arkhipkin,14 G. S. Averichev,13 Y. Bai,30 J. Balewski,18 O.... Barannikova,10 L. S. Barnby,2 J. Baudot,19 S. Baumgart,52 D. R. Beavis,3 R. Bellwied,50 F. Benedosso,30 R. R. Betts,10 S. Bhardwaj,37 A. Bhasin,20 A. K. Bhati,32 H. Bichsel,49 J. Bielcik,12 J. Bielcikova,12 L. C. Bland,3 S.-L. Blyth,24 M. Bombara,2 B. E...

  2. J/psi production in relativistic heavy ion collisions from a multiphase transport model 

    E-Print Network [OSTI]

    Zhang, B.; Ko, Che Ming; Li, Ba; Lin, ZW; Pal, S.

    2002-01-01

    Using a multiphase transport model, we study J/psi production from interactions between charm and anticharm quarks in the initial parton phase and between D and (D) over bar mesons in the final hadron phase of relativistic ...

  3. Heavy Quark Kinetic Energy in B Mesons by a QCD Relativistic Potential Model

    E-Print Network [OSTI]

    F. De Fazio

    1996-11-04

    The matrix element of the kinetic energy operator between B meson states is computed by means of a QCD relativistic potential model, with the result: $\\mu_\\pi^2=0.66 GeV^2$. A comparison with the outcome of other theoretical approaches and a discussion of the phenomenological implications of this result are carried out.

  4. 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...

  5. Effect of the Wood-Saxon nuclear distribution on the chiral magnetic field in Relativistic Heavy-ion Collisions

    E-Print Network [OSTI]

    Yu-Jun Mo; Sheng-Qin Feng; Ya-Fei Shi

    2013-08-20

    The formation of the QCD vacuum with nonzero winding number $Q_w$ during relativistic heavy-ion collisions breaks the parity and charge-parity symmetry. A new kind of field configuration can separate charge in the presence of a background magnetic field-the "chiral magnetic effect". The strong magnetic field and the QCD vacuum can both completely be produced in the noncentral nuclear-nuclear collision. Basing on the theory of Kharzeev,Mclerran and Warringa, we use the Wood-Saxon nucleon distribution to replace that of the uniform distribution to improve the magnetic field calculation method of the noncentral collision. The chiral magnetic field distribution at LHC(Large Hadron Collider) energy regions are predicted. We also consider the contributions to the magnetic field of the total charge given by the produced quarks.

  6. Energy and Atomic Mass Dependence of Nuclear Stopping Power in Relativistic Heavy-Ion Collisions in Interacting Gluon Model

    E-Print Network [OSTI]

    Q. J. Liu; W. Q. Chao; G. Wilk

    1995-04-05

    We present a Monte-Carlo simulation of energy deposition process in relativistic heavy-ion collisions based on a new realization of the Interacting-Gluon-Model (IGM) for high energy $N-N$ collisions. In particular we show results for proton spectra from collisions of $E_{lab}=200 \\ GeV/N$ $^{32}$S beam incident on $^{32}$S target and analyze the energy and mass dependence of nuclear stopping power predicted by our model. Theoretical predictions for proton rapidity distributions of both $^{208}$Pb + $^{208}$Pb collisions at $E_{lab}=160 \\ GeV/N$ CERN SPS and $^{197}$Au + $^{197}$Au at $\\sqrt{s_{NN}}=200 \\ GeV$ BNL RHIC are given.

  7. Recent results in relativistic heavy ion collisions: from ``a new state of matter'' to "the perfect fluid"

    E-Print Network [OSTI]

    M. J. Tannenbaum

    2006-07-28

    Experimental Physics with Relativistic Heavy Ions dates from 1992 when a beam of 197Au of energy greater than 10A GeV/c first became available at the Alternating Gradient Synchrotron (AGS) at Brookhaven National Laboratory (BNL) soon followed in 1994 by a 208Pb beam of 158A GeV/c at the Super Proton Synchrotron (SPS) at CERN (European Center for Nuclear Research). Previous pioneering measurements at the Berkeley Bevalac in the late 1970's and early 1980's were at much lower bombarding energies (~ 1 A GeV/c) where nuclear breakup rather than particle production is the dominant inelastic process in A+A collisions. More recently, starting in 2000, the Relativistic Heavy Ion Collider (RHIC) at BNL has produced head-on collisions of two 100A GeV beams of fully stripped Au ions, corresponding to nucleon-nucleon center-of-mass energy, sqrt(sNN)=200 GeV, total c.m. energy 200A GeV. The objective of this research program is to produce nuclear matter with extreme density and temperature, possibly resulting in a state of matter where the quarks and gluons normally confined inside individual nucleons (r < 1 fm) are free to act over distances an order of magnitude larger. Progress from the period 1992 to the present will be reviewed, with reference to previous results from light ion and proton-proton collisions where appropriate. Emphasis will be placed on the measurements which formed the basis for the announcements by the two major laboratories: "A new state of matter", by CERN on Feb 10, 2000 and "The perfect fluid", by BNL on April 19, 2005.

  8. Search for a heavy Standard Model Higgs boson in the channel H->ZZ->llqq using the ATLAS detector

    E-Print Network [OSTI]

    The ATLAS Collaboration

    2011-11-30

    A search for a heavy Standard Model Higgs boson decaying via H->ZZ->llqq, where l=e,mu, is presented. The search is performed using a data set of pp collisions at sqrt(s)=7 TeV, corresponding to an integrated luminosity of 1.04 fb^-1 collected in 2011 by the ATLAS detector at the CERN LHC collider. No significant excess of events above the estimated background is found. Upper limits at 95% confidence level on the production cross section (relative to that expected from the Standard Model) of a Higgs boson with a mass in the range between 200 and 600 GeV are derived. Within this mass range, there is at present insufficient sensitivity to exclude a Standard Model Higgs boson. For a Higgs boson with a mass of 360 GeV, where the sensitivity is maximal, the observed and expected cross section upper limits are factors of 1.7 and 2.7, respectively, larger than the Standard Model prediction.

  9. Search for a heavy Standard Model Higgs boson in the channel H?ZZ?????qq¯ using the ATLAS detector

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

    Aad, G.; Abbott, B.; Abdallah, J.; Abdelalim, A. A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Abreu, H.; et al

    2012-01-01

    A search for a heavy Standard Model Higgs boson decaying via H ? ZZ ? ????qq¯, where ? = e,?, is presented. The search is performed using a data set of pp collisions at ?s = 7 TeV, corresponding to an integrated luminosity of 1.04 fb?¹ collected in 2011 by the ATLAS detector at the CERN LHC collider. No significant excess of events above the estimated background is found. Upper limits at 95% confidence level on the production cross section (relative to that expected from the Standard Model) of a Higgs boson with a mass in the range between 200more »and 600 GeV are derived. Within this mass range, there is at present insufficient sensitivity to exclude a Standard Model Higgs boson. For a Higgs boson with a mass of 360 GeV, where the sensitivity is maximal, the observed and expected cross section upper limits are factors of 1.7 and 2.7, respectively, larger than the Standard Model prediction.« less

  10. Search for an additional heavy Higgs boson in the H->ZZ->2l2q/2v2q decay channel with ATLAS detector

    E-Print Network [OSTI]

    Wang, Chao; The ATLAS collaboration

    2015-01-01

    In July 2012, the ATLAS and CMS experiments at LHC reported the observation of a new particle with a mass of about 125GeV and with properties consistent with the expected SM Higgs boson. It's important to verify whether this new particle is part of an extended scalar sector as populated by various extensions to the SM such as 2HDM and EWS model, and searching for the additional Higgs can help us to better understand EWSB process, as well as precision measurement of the 125GeV resonance. The additional heavy Higgs search with centre-of-mass energy of 8TeV with an integrated luminosity of 20.3$fb^{-1}$ data collected by ATLAS detector is presented here, the mass range in this search is from 200GeV(llqq)/400GeV(vvqq) to 1TeV.

  11. Event-shape fluctuations and flow correlations in ultra-relativistic heavy-ion collisions

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

    Jia, Jiangyong

    2014-12-01

    I review recent measurements of a large set of flow observables associated with event-shape fluctuations and collective expansion in heavy ion collisions. First, these flow observables are classified and experiment methods are introduced. The experimental results for each type of observables are then presented and compared to theoretical calculations. A coherent picture of initial condition and collective flow based on linear and non-linear hydrodynamic responses is derived, which qualitatively describe most experimental results. I discuss new types of fluctuation measurements that can further our understanding of the event-shape fluctuations and collective expansion dynamics.

  12. Search for heavy long-lived multi-charged particles in pp collisions at ?s = 8  TeV using the ATLAS detector

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

    None

    2015-08-08

    A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at ?s = 8 TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb-1 are examined. Particles producing anomalously high ionisation, consistent with long-lived massive particles with electric charges from |q| = 2e to |q| = 6e are searched for. No signal candidate events are observed, and 95 % confidence level cross-section upper limits are interpreted as lower mass limits for a Drell–Yan production model. The mass limits range between 660 and 785 GeV.

  13. Search for heavy long-lived multi-charged particles in pp collisions at $$\\sqrt{s}=8$$ s = 8  TeV using the ATLAS detector

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

    Aad, G.

    2015-08-08

    A search for heavy long-lived multi-charged particles is performed using the ATLAS detector at the LHC. Data collected in 2012 at s?=8 TeV from pp collisions corresponding to an integrated luminosity of 20.3 fb-1are examined. Particles producing anomalously high ionisation, consistent with long-lived massive particles with electric charges from |q| = 2e to |q| = 6e are searched for. No signal candidate events are observed, and 95 % confidence level cross-section upper limits are interpreted as lower mass limits for a Drell–Yan production model. The mass limits range between 660 and 785 GeV.

  14. The Smallest Drops of the Hottest Matter? New Investigations at the Relativistic Heavy Ion Collider (493rd Brookhaven Lecture)

    SciTech Connect (OSTI)

    Sickles, Anne

    2014-03-19

    Pool sharks at the billiards hall know that sometimes you aim to rocket the cue ball for a head-on collision, and other times, a mere glance will do. Physicists need to know more than a thing or two about collision geometry too, as they sift through data from the billions of ions that smash together at the Relativistic Heavy Ion Collider (RHIC). Determining whether ions crash head-on or just glance is crucial for the physicists analyzing data to study quark-gluon plasma—the ultra-hot, "perfect" liquid of quarks and gluons that existed more than 13 billion years ago, before the first protons and neutrons formed. For these physicists, collision geometry data provides insights about quark-gluon plasma's extremely low viscosity and other unusual properties, which are essential for understanding more about the "strong force" that holds together the nucleus, protons, and neutrons of every atom in the universe. Dr. Sickles explains how physicists use data collected at house-sized detectors like PHENIX and STAR to determine what happens before, during, and after individual particle collisions among billions at RHIC. She also explains how the ability to collide different "species" of nuclei at RHIC—including protons and gold ions today and possibly more with a proposed future electron-ion collider upgrade (eRHIC)—enables physicists to probe deeper into the mysteries of quark-gluon plasma and the strong force.

  15. Interactions of $B_{c}$ Meson in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Irfan, Shaheen; Masud, Bilal

    2015-01-01

    We calculate the absorbtion cross-sections of $B_{c}$ mesons by $\\pi$ and $\\rho$ mesons including anomalous processes using an effective hadronic Lagrangian. The enhancement of Bc production is expected due to QGP formation in heavy-ion experiments. However it is also expected that the production rate of Bc meson can be affected due to the interaction with comovers. These processes are relevant for experiments at RHIC. Thermal average cross-sections of $B_{c}$ are evaluated with form factor when a cut off parameter in it is 1 and 2 GeV. Using these thermal average cross-sections in the kinetic equation we investigate the time evolution of $B_{c}$ mesons due to dissociation in the hadronic matter formed at RHIC.

  16. A Tale of Tails: Photon Rates and Flow in Ultra-Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Larry McLerran; Bjoern Schenke

    2015-04-28

    We consider the possibility that quark and gluon distributions in the medium created in high energy heavy ion collisions may be modified by a power law tail at energies much higher than the temperature. We parametrize such a tail by Tsallis distributions with an exponent motivated by phenomenology. These distributions are characterized by an effective temperature scale that we assume to evolve in time like the temperature for thermal distributions. We find that including such a tail increases the rates for photon production and significantly delays the emission times for photons of a fixed energy. We argue that these effects are sufficiently large that they should be able to account for photon yields and flow patterns seen in LHC and RHIC experiments.

  17. Quark charge balance function and hadronization effects in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Jun Song; Feng-lan Shao; Zuo-tang Liang

    2012-04-17

    We calculate the charge balance function of the bulk quark system before hadronization and those for the directly produced and the final hadron system in high energy heavy ion collisions. We use the covariance coefficient to describe the strength of the correlation between the momentum of the quark and that of the anti-quark if they are produced in a pair and fix the parameter by comparing the results for hadrons with the available data. We study the hadronization effects and decay contributions by comparing the results for hadrons with those for the bulk quark system. Our results show that while hadronization via quark combination mechanism slightly increases the width of the charge balance functions, it preserves the main features of these functions such as the longitudinal boost invariance and scaling properties in rapidity space. The influence from resonance decays on the width of the balance function is more significant but it does not destroy its boost invariance and scaling properties in rapidity space either. The balance functions in azimuthal direction are also presented.

  18. 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.

  19. Search for a heavy gauge boson decaying to a charged lepton and a neutrino in 1 fb[superscript ?1] of pp collisions at ?s = 7 TeV using the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector at the LHC is used to search for high-mass states, such as heavy charged gauge bosons (W?), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of ...

  20. B-meson decay constants from 2+1-flavor lattice QCD with domain-wall light quarks and relativistic heavy quarks

    E-Print Network [OSTI]

    Norman H. Christ; Jonathan M. Flynn; Taku Izubuchi; Taichi Kawanai; Christoph Lehner; Amarjit Soni; Ruth S. Van de Water; Oliver Witzel

    2015-02-02

    We calculate the B-meson decay constants f_B, f_Bs, and their ratio in unquenched lattice QCD using domain-wall light quarks and relativistic b-quarks. We use gauge-field ensembles generated by the RBC and UKQCD collaborations using the domain-wall fermion action and Iwasaki gauge action with three flavors of light dynamical quarks. We analyze data at two lattice spacings of a ~ 0.11, 0.086 fm with unitary pion masses as light as M_pi ~ 290 MeV; this enables us to control the extrapolation to the physical light-quark masses and continuum. For the b-quarks we use the anisotropic clover action with the relativistic heavy-quark interpretation, such that discretization errors from the heavy-quark action are of the same size as from the light-quark sector. We renormalize the lattice heavy-light axial-vector current using a mostly nonperturbative method in which we compute the bulk of the matching factor nonperturbatively, with a small correction, that is close to unity, in lattice perturbation theory. We also improve the lattice heavy-light current through O(alpha_s a). We extrapolate our results to the physical light-quark masses and continuum using SU(2) heavy-meson chiral perturbation theory, and provide a complete systematic error budget. We obtain f_B0 = 199.5(12.6) MeV, f_B+ = 195.6(14.9) MeV, f_Bs = 235.4(12.2) MeV, f_Bs/f_B0 = 1.197(50), and f_Bs/f_B+ = 1.223(71), where the errors are statistical and total systematic added in quadrature. These results are in good agreement with other published results and provide an important independent cross check of other three-flavor determinations of $B$-meson decay constants using staggered light quarks.

  1. ATLAS search for a heavy gauge boson decaying to a charged lepton and a neutrino in pp collisions at ?s = 7 TeV

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

    Aad, G.

    2012-12-08

    The ATLAS detector at the LHC is used to search for high-mass states, such as heavy charged gauge bosons (W'), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp collisions at a centre-of-mass energy of 7 TeV corresponding to an integrated luminosity of 4.7 fb-1. No excess beyond Standard Model expectations is observed. A W' with Sequential Standard Model couplings is excluded at the 95% credibility level for masses up to 2.55 TeV. Excited chiral bosons (W*) with equivalent coupling strength are excluded for masses up to 2.42 TeV.

  2. RELATIVISTIC HEAVY ION PHYSICS

    E-Print Network [OSTI]

    Westfall, G.D.

    2010-01-01

    Viyogi, G.D. Westfall; P. Doll, D.E. Greiner, H. Faraggi,Viyogi, T.J.M. Symons, P. Doll, D.E. Greiner, H.H. Heckman,

  3. Search for heavy lepton resonances decaying to a Z boson and a lepton in pp collisions at \\( \\sqrt{s}=8 \\) TeV with the ATLAS detector

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

    Aad, G.

    2015-09-16

    In this study, a search for heavy leptons decaying to a Z boson and an electron or a muon is presented. The search is based on pp collision data taken at \\( \\sqrt{s}=8 \\) TeV by the ATLAS experiment at the CERN Large Hadron Collider, corresponding to an integrated luminosity of 20.3 fb?¹. Three high-transverse-momentum electrons or muons are selected, with two of them required to be consistent with originating from a Z boson decay. No significant excess above Standard Model background predictions is observed, and 95% confidence level limits on the production cross section of high-mass trilepton resonances aremore »derived. The results are interpreted in the context of vector-like lepton and type-III seesaw models. For the vector-like lepton model, most heavy lepton mass values in the range 114–176 GeV are excluded. For the type-III seesaw model, most mass values in the range 100–468 GeV are excluded.« less

  4. Searches for heavy long-lived charged particles with the ATLAS detector in proton--proton collisions at $\\sqrt{s}$ = 8 TeV

    E-Print Network [OSTI]

    Aad, Georges; Abdallah, Jalal; Abdel Khalek, Samah; Abdinov, Ovsat; Aben, Rosemarie; Abi, Babak; Abolins, Maris; AbouZeid, Ossama; Abramowicz, Halina; Abreu, Henso; Abreu, Ricardo; Abulaiti, Yiming; Acharya, Bobby Samir; Adamczyk, Leszek; Adams, David; Adelman, Jahred; Adomeit, Stefanie; Adye, Tim; Agatonovic-Jovin, Tatjana; Aguilar-Saavedra, Juan Antonio; Agustoni, Marco; Ahlen, Steven; Ahmadov, Faig; Aielli, Giulio; Akerstedt, Henrik; Åkesson, Torsten Paul Ake; Akimoto, Ginga; Akimov, Andrei; Alberghi, Gian Luigi; Albert, Justin; Albrand, Solveig; Alconada Verzini, Maria Josefina; Aleksa, Martin; Aleksandrov, Igor; Alexa, Calin; Alexander, Gideon; Alexandre, Gauthier; Alexopoulos, Theodoros; Alhroob, Muhammad; Alimonti, Gianluca; Alio, Lion; Alison, John; Allbrooke, Benedict; Allison, Lee John; Allport, Phillip; Aloisio, Alberto; Alonso, Alejandro; Alonso, Francisco; Alpigiani, Cristiano; Altheimer, Andrew David; Alvarez Gonzalez, Barbara; Alviggi, Mariagrazia; Amako, Katsuya; Amaral Coutinho, Yara; Amelung, Christoph; Amidei, Dante; Amor Dos Santos, Susana Patricia; Amorim, Antonio; Amoroso, Simone; Amram, Nir; Amundsen, Glenn; Anastopoulos, Christos; Ancu, Lucian Stefan; Andari, Nansi; Andeen, Timothy; Anders, Christoph Falk; Anders, Gabriel; Anderson, Kelby; Andreazza, Attilio; Andrei, George Victor; Anduaga, Xabier; Angelidakis, Stylianos; Angelozzi, Ivan; Anger, Philipp; Angerami, Aaron; Anghinolfi, Francis; Anisenkov, Alexey; Anjos, Nuno; Annovi, Alberto; Antonaki, Ariadni; Antonelli, Mario; Antonov, Alexey; Antos, Jaroslav; Anulli, Fabio; Aoki, Masato; Aperio Bella, Ludovica; Apolle, Rudi; Arabidze, Giorgi; Aracena, Ignacio; Arai, Yasuo; Araque, Juan Pedro; Arce, Ayana; Arduh, Francisco Anuar; Arguin, Jean-Francois; Argyropoulos, Spyridon; Arik, Metin; Armbruster, Aaron James; Arnaez, Olivier; Arnal, Vanessa; Arnold, Hannah; Arratia, Miguel; Arslan, Ozan; Artamonov, Andrei; Artoni, Giacomo; Asai, Shoji; Asbah, Nedaa; Ashkenazi, Adi; Åsman, Barbro; Asquith, Lily; Assamagan, Ketevi; Astalos, Robert; Atkinson, Markus; Atlay, Naim Bora; Auerbach, Benjamin; Augsten, Kamil; Aurousseau, Mathieu; Avolio, Giuseppe; Axen, Bradley; Azuelos, Georges; Azuma, Yuya; Baak, Max; Baas, Alessandra; Bacci, Cesare; Bachacou, Henri; Bachas, Konstantinos; Backes, Moritz; Backhaus, Malte; Backus Mayes, John; Badescu, Elisabeta; Bagiacchi, Paolo; Bagnaia, Paolo; Bai, Yu; Bain, Travis; Baines, John; Baker, Oliver Keith; Balek, Petr; Balli, Fabrice; Banas, Elzbieta; Banerjee, Swagato; Bannoura, Arwa A E; Bansal, Vikas; Bansil, Hardeep Singh; Barak, Liron; Baranov, Sergei; Barberio, Elisabetta Luigia; Barberis, Dario; Barbero, Marlon; Barillari, Teresa; Barisonzi, Marcello; Barklow, Timothy; Barlow, Nick; Barnes, Sarah Louise; Barnett, Bruce; Barnett, Michael; Barnovska, Zuzana; Baroncelli, Antonio; Barone, Gaetano; Barr, Alan; Barreiro, Fernando; Barreiro Guimarães da Costa, João; Bartoldus, Rainer; Barton, Adam Edward; Bartos, Pavol; Bartsch, Valeria; Bassalat, Ahmed; Basye, Austin; Bates, Richard; Batista, Santiago Juan; Batley, Richard; Battaglia, Marco; Battistin, Michele; Bauer, Florian; Bawa, Harinder Singh; Beattie, Michael David; Beau, Tristan; Beauchemin, Pierre-Hugues; Beccherle, Roberto; Bechtle, Philip; Beck, Hans Peter; Becker, Anne Kathrin; Becker, Sebastian; Beckingham, Matthew; Becot, Cyril; Beddall, Andrew; Beddall, Ayda; Bedikian, Sourpouhi; Bednyakov, Vadim; Bee, Christopher; Beemster, Lars; Beermann, Thomas; Begel, Michael; Behr, Katharina; Belanger-Champagne, Camille; Bell, Paul; Bell, William; Bella, Gideon; Bellagamba, Lorenzo; Bellerive, Alain; Bellomo, Massimiliano; Belotskiy, Konstantin; Beltramello, Olga; Benary, Odette; Benchekroun, Driss; Bendtz, Katarina; Benekos, Nektarios; Benhammou, Yan; Benhar Noccioli, Eleonora; Benitez Garcia, Jorge-Armando; Benjamin, Douglas; Bensinger, James; Bentvelsen, Stan; Berge, David; Bergeaas Kuutmann, Elin; Berger, Nicolas; Berghaus, Frank; Beringer, Jürg; Bernard, Clare; Bernat, Pauline; Bernius, Catrin; Bernlochner, Florian Urs; Berry, Tracey; Berta, Peter; Bertella, Claudia; Bertoli, Gabriele; Bertolucci, Federico; Bertsche, Carolyn; Bertsche, David; Besana, Maria Ilaria; Besjes, Geert-Jan; Bessidskaia, Olga; Bessner, Martin Florian; Besson, Nathalie; Betancourt, Christopher; Bethke, Siegfried; Bhimji, Wahid; Bianchi, Riccardo-Maria; Bianchini, Louis; Bianco, Michele; Biebel, Otmar; Bieniek, Stephen Paul; Bierwagen, Katharina; Biesiada, Jed; Biglietti, Michela; Bilbao De Mendizabal, Javier; Bilokon, Halina; Bindi, Marcello; Binet, Sebastien

    2015-01-01

    Searches for heavy long-lived charged particles are performed using a data sample of 19.8 fb$^{-1}$ from proton--proton collisions at a centre-of-mass energy of $\\sqrt{s}$ = 8 TeV collected by the ATLAS detector at the Large Hadron Collider. No excess is observed above the estimated background and limits are placed on the mass of long-lived particles in various supersymmetric models. Long-lived tau sleptons in models with gauge-mediated symmetry breaking are excluded up to masses between 440 and 385 GeV for tan(beta) between 10 and 50, with a 290 GeV limit in the case where only direct tau slepton production is considered. In the context of simplified LeptoSUSY models, where sleptons are stable and have a mass of 300 GeV, squark and gluino masses are excluded up to a mass of 1500 and 1360 GeV, respectively. Directly produced charginos, in simplified models where they are nearly degenerate to the lightest neutralino, are excluded up to a mass of 620 GeV. R-hadrons, composites containing a gluino, bottom squar...

  5. Searches for heavy long-lived charged particles with the ATLAS detector in proton-proton collisions at ?s = 8 TeV

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

    Aad, G.

    2015-01-14

    Searches for heavy long-lived charged particles are performed using a data sample of 19.1 fb-1 from proton-proton collisions at a centre-of-mass energy of \\( \\sqrt{s}=8 \\) TeV collected by the ATLAS detector at the Large Hadron Collider. No excess is observed above the estimated background and limits are placed on the mass of long-lived particles in various supersymmetric models. Long-lived tau sleptons in models with gauge-mediated symmetry breaking are excluded up to masses between 440 and 385 GeV for tan ? between 10 and 50, with a 290 GeV limit in the case where only direct tau slepton production ismore »considered. In the context of simplified LeptoSUSY models, where sleptons are stable and have a mass of 300 GeV, squark and gluino masses are excluded up to a mass of 1500 and 1360 GeV, respectively. Directly produced charginos, in simplified models where they are nearly degenerate to the lightest neutralino, are excluded up to a mass of 620 GeV. As a result, R-hadrons, composites containing a gluino, bottom squark or top squark, are excluded up to a mass of 1270, 845 and 900 GeV, respectively, using the full detector; and up to a mass of 1260, 835 and 870 GeV using an approach disregarding information from the muon spectrometer.« less

  6. Search for a Heavy Particle Decaying into an Electron and a Muon with the ATLAS Detector in s = 7 ? ? TeV p p collisions at the LHC

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

    Aad, G; Abbott, B.; Abdallah, J; Abdelalim, A. A.; Abdesselam, A.; Abdinov, B; Abolins, M; Abramowicz, H.; Abreu, E.; Acharya, B. S.; et al

    2011-06-22

    This Letter presents the first search for a heavy particle decaying into an e±?? final state in ?s=7??TeV pp collisions at the LHC. The data were recorded by the ATLAS detector during 2010 and correspond to a total integrated luminosity of 35??pb?¹. No excess above the standard model background expectation is observed. Exclusions at 95% confidence level are placed on two representative models. In an R-parity violating supersymmetric model, tau sneutrinos with a mass below 0.75 TeV are excluded, assuming all R-parity violating couplings are zero except ??311=0.11 and ?312=0.07. In a lepton flavor violating model, a Z?-like vector bosonmore »with masses of 0.70–1.00 TeV and corresponding cross sections times branching ratios of 0.175–0.183 pb is excluded. These results extend to higher mass R-parity violating sneutrinos and lepton flavor violating Z’s than previous constraints from the Tevatron.« less

  7. Search for dark matter in events with heavy quarks and missing transverse momentum in pp collisions with the ATLAS detector

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

    Aad, G.

    2015-02-24

    This article reports on a search for dark matter pair production in association with bottom or top quarks in 20.3 fb–1 of pp collisions collected at ?s=8 TeV by the ATLAS detector at the LHC. Events with large missing transverse momentum are selected when produced in association with high-momentum jets of which one or more are identified as jets containing b-quarks. Final states with top quarks are selected by requiring a high jet multiplicity and in some cases a single lepton. The data are found to be consistent with the Standard Model expectations and limits are set on the massmore »scale of effective field theories that describe scalar and tensor interactions between dark matter and Standard Model particles. Limits on the dark-matter–nucleon cross-section for spin-independent and spin-dependent interactions are also provided. These limits are particularly strong for low-mass dark matter. Using a simplified model, constraints are set on the mass of dark matter and of a colored mediator suitable to explain a possible signal of annihilating dark matter.« less

  8. Relativistic Noise

    E-Print Network [OSTI]

    Joseph Kapusta; Berndt Mueller; Misha Stephanov

    2012-01-17

    The relativistic theory of hydrodynamic fluctuations, or noise, is derived and applied to high energy heavy ion collisions. These fluctuations are inherent in any space-time varying system and are in addition to initial state fluctuations. We illustrate the effects with the boost-invariant Bjorken solution to the hydrodynamic equations. Long range correlations in rapidity are induced by propagation of sound modes. The magnitude of these correlations are directly proportional to the viscosities. These fluctuations should be enhanced near a phase transition or rapid crossover.

  9. Search for a heavy gauge boson decaying to a charged lepton and a neutrino in 1 fb-1 of pp collisions at ?s=7 TeV using the ATLAS detector

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

    Aad, G.

    2011-11-01

    The ATLAS detector at the LHC is used to search for heavy charged gauge bosons (W'), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp collisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 1.04 fb?¹. No excess beyond Standard Model expectations is observed. A W' with Sequential Standard Model couplings is excluded at the 95% confidence level for masses up to 2.15 TeV.

  10. Net-baryon-, net-proton-, and net-charge kurtosis in heavy-ion collisions within a relativistic transport approach

    E-Print Network [OSTI]

    Marlene Nahrgang; Tim Schuster; Michael Mitrovski; Reinhard Stock; Marcus Bleicher

    2012-09-03

    We explore the potential of net-baryon, net-proton and net-charge kurtosis measurements to investigate the properties of hot and dense matter created in relativistic heavy-ion collisions. Contrary to calculations in a grand canonical ensemble we explicitly take into account exact electric and baryon charge conservation on an event-by-event basis. This drastically limits the width of baryon fluctuations. A simple model to account for this is to assume a grand-canonical distribution with a sharp cut-off at the tails. We present baseline predictions of the energy dependence of the net-baryon, net-proton and net-charge kurtosis for central ($b\\leq 2.75$ fm) Pb+Pb/Au+Au collisions from $E_{lab}=2A$ GeV to $\\sqrt{s_{NN}}=200$ GeV from the UrQMD model. While the net-charge kurtosis is compatible with values around zero, the net-baryon number decreases to large negative values with decreasing beam energy. The net-proton kurtosis becomes only slightly negative for low $\\sqrt{s_{NN}}$.

  11. Realistic expanding source model for invariant one-particle multiplicity distributions and two-particle correlations in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Chapman, S; Chapman, Scott; Nix, J Rayford

    1996-01-01

    We present a realistic expanding source model with nine parameters that are necessary and sufficient to describe the main physics occuring during hydrodynamical freezeout of the excited hadronic matter produced in relativistic heavy-ion collisions. As a first test of the model, we compare it to data from central Si + Au collisions at p_lab/A = 14.6 GeV/c measured in experiment E-802 at the AGS. An overall chi-square per degree of freedom of 1.055 is achieved for a fit to 1416 data points involving invariant pi^+, pi^-, K^+, and K^- one-particle multiplicity distributions and pi^+ and K^+ two-particle correlations. The 99-percent-confidence region of parameter space is identified, leading to one-dimensional error estimates on the nine fitted parameters and other calculated physical quantities. Three of the most important results are the freezeout temperature, longitudinal proper time, and baryon density along the symmetry axis. For these we find values of 92.9 +/- 4.4 MeV, 8.2 +/- 2.2 fm/c, and 0.0222 + 0.0097...

  12. THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) CRYOGENIC SYSTEM AT BNL: REVIEW OF THE MODIFICATIONS AND UPGRADES SINCE 2002 AND PLANNED IMPROVEMENTS.

    SciTech Connect (OSTI)

    THAN,Y.R.; TUOZZOLO, J.; SIDI-YAKHLEF, A.; GANNI, V.; KNUDSEN, P.; ARENIUS, D.

    2007-07-16

    Brookhaven National Laboratory continues its multi-year program to improve the operational efficiency, reliability, and stability of the cryogenic system which also resulted in improved beam availability of the Relativistic Heavy Ion Collider (RHIC). This paper summarizes the work and changes made after each phase over the past four years to the present, as well as proposed future improvements. Power usage dropped from an initial 9.4 MW to the present 5.1 MW and is expected to drop below 5 MW after the completion of the remaining proposed improvements. The work proceeded in phases by balancing the Collider's schedule of operation, time required for the modifications and budget constraints. The main changes include process control, compressor oil removal and management, elimination of the use of cold compressors and two liquid helium storage tanks, insulation of the third liquid helium storage tank, compressor bypass flow reduction and the addition of a load turbine (Joule-Thompson expander) with associated heat exchangers at the cold end of the plant. Also, liquid helium pumps used for forced circulation of the sub-cooled helium through the magnet loops were eliminated by an accelerator supply flow reconfiguration. Planned future upgrades include the resizing of expanders 5 and 6 to increase their efficiencies.

  13. Multiphase transport model for relativistic nuclear collisions 

    E-Print Network [OSTI]

    Zhang, B.; Ko, Che Ming; Li, Ba; Lin, ZW.

    2000-01-01

    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. ...

  14. Jet suppression and the flavor dependence of partonic energy loss with ATLAS

    E-Print Network [OSTI]

    Kosek, Tomas; The ATLAS collaboration

    2015-01-01

    In relativistic heavy ion collisions, a hot medium with a high density of unscreened color charges is produced. One manifestation of the energy loss of jets propagating through the medium is a lower yield of jets emerging from the medium than ?expected in the absence of medium effects. Therefore modifications of the jet yield are directly sensitive to the energy loss mechanism. Furthermore, jets with different ?flavor content are expected to be affected by the medium in different ways. Parton showers initiated by quarks tend to have fewer fragments carrying a larger fraction of ?the total jet energy than those resulting from gluons. Jets containing heavy quarks may lose less energy as the large quark mass suppresses the amount of medium-induced ?radiation. This would lead to different relative contributions of inelastic and elastic energy loss. In this talk, the latest ATLAS results on single jet suppression will ?be presented. Measurements of the nuclear modification factor, RAA, for fully reconstr...

  15. Search for heavy long-lived charged particles with the ATLAS detector in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for long-lived charged particles reaching the muon spectrometer is performed using a data sample of 37 pb[superscript ?1] from pp collisions at ?s = 7 TeV collected by the ATLAS detector at the LHC in 2010. No ...

  16. Searches for heavy long-lived sleptons and R-hadrons with the ATLAS detector in pp collisions at ?s = 7 TeV

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for long-lived particles is performed using a data sample of 4.7 fb[superscript ?1] from proton–proton collisions at a centre-of-mass energy ?s = 7 TeV collected by the ATLAS detector at the LHC. No excess is ...

  17. 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.

  18. RELATIVISTIC HEAVY ION COLLISIONS: EXPERIMENT

    E-Print Network [OSTI]

    Friedlander, Erwin M.

    2010-01-01

    63, Sc 63, Gu 76, Go 77, Ka 80a] and thermodynamic [Me 80,by Meyer et al. [Me 80a],where the transverse momenta of thechamber experiment [ ~ a 80a] with 1.8 AGeV 4 0 ~ r incident

  19. Initial state in relativistic nuclear collisions and Color Glass Condensate

    E-Print Network [OSTI]

    F. Gelis

    2014-12-01

    In this talk, I discuss recent works related to the pre-hydrodynamical stages of ultra-relativistic heavy ion collisions.

  20. Search for a heavy Standard Model Higgs boson in the channel H?ZZ??[superscript +]?[superscript ?]q[bar over q] using the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for a heavy Standard Model Higgs boson decaying via View the H?ZZ??[superscript +]?[superscript ?]q[bar over q], where ?=e,? is presented. The search is performed using a data set of pp collisions at ?s = 7 TeV, ...

  1. Study of heavy-flavor quarks produced in association with top-quark pairs at ?s = 7 TeV using the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    Using a sample of dilepton top-quark pair (t[bar over t]) candidate events, a study is performed of the production of top-quark pairs together with heavy-flavor (HF) quarks, the sum of t[bar over t] + b + X and t[bar over ...

  2. Search for pair-produced heavy quarks decaying to Wq in the two-lepton channel at ?(s)=7??TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for heavy-quark pair production (QQ?) under the decay hypothesis QQ??W[superscript +]qW[superscript -]q? with q=d, s, b for up-type Q or q=u, c for down-type Q. The search is performed with ...

  3. Jet suppression and the flavor dependence of partonic energy loss with ATLAS

    E-Print Network [OSTI]

    Kosek, Tomas; The ATLAS collaboration

    2016-01-01

    In relativistic heavy ion collisions, a hot medium with a high density of unscreened color charges is produced. One manifestation of the energy loss of jets propagating through the medium is a lower yield of jets and hadrons emerging from this medium than expected in the absence of medium effects. Therefore modifications of the jet yield are directly sensitive to the energy loss mechanism. Furthermore, jets with different flavor content are expected to be affected by the medium in different ways. In this publication, the latest ATLAS results on single hadron suppression along with the complementary measurements of single jet suppression are presented. Rapidity dependence, which is sensitive to the relative energy loss between quark and gluon jets, is discussed. Finally, a new measurement of jet fragmentation functions is presented.

  4. ATLAS Data Preservation Policy

    E-Print Network [OSTI]

    The ATLAS collaboration

    2015-01-01

    The principal intent of this document is to describe the ATLAS policy ensuring that its data are maintained reliably in a form accessible to ATLAS members. A separate document describes the ATLAS policy for making its data available, and potentially useful, to scientists who are not members of ATLAS.

  5. The "ripples" on relativistically expanding fluid

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

    Shi, Shuzhe [Tsinghua Univ., and Collaborative Innovation Center of Quantum Matter, Beijing (China); Liao, Jinfeng [Indiana Univ., Bloomington, IN (United States); Brookhaven National Lab., Upton, NY (United States); Zhuang, Pengfei [Tsinghua Univ., and Collaborative Innovation Center of Quantum Matter, Beijing (China)

    2014-12-01

    Recent studies have shown that fluctuations of various types play important roles in the evolution of the fireball created in relativistic heavy ion collisions and bear many phenomenological consequences for experimental observables. The bulk dynamics of the fireball is well described by relativistic hydrodynamic expansion and the fluctuations on top of such expanding background can be studied within the linearized hydrodynamic framework. In this paper we present complete and analytic sound wave solutions on top of both Bjorken flow and Hubble flow backgrounds.

  6. The "ripples" on relativistically expanding fluid

    SciTech Connect (OSTI)

    Shi, Shuzhe; Liao, Jinfeng; Zhuang, Pengfei

    2014-12-29

    Recent studies have shown that fluctuations of various types play important roles in the evolution of the fireball created in relativistic heavy ion collisions and bear many phenomenological consequences for experimental observables. The bulk dynamics of the fireball is well described by relativistic hydrodynamic expansion and the fluctuations on top of such expanding background can be studied within the linearized hydrodynamic framework. In this paper we present complete and analytic sound wave solutions on top of both Bjorken flow and Hubble flow backgrounds.

  7. Overview of the Atlas project

    SciTech Connect (OSTI)

    Trainor, R.J.; Ballard, E.O.; Bartsch, R.R. [and others

    1997-09-01

    Atlas is a high energy pulsed power facility under development at Los Alamos National Laboratory to perform high energy-density experiments in support of the Department of Energy`s stockpile stewardship responsibility. Its design is optimized for materials properties and hydrodynamics experiments under extreme conditions. Atlas will be operational in late-1999 and is designed to provide 100 shots per year. The Atlas capacitor bank design consists of a 36-MJ array of 240-kV Marx modules. The system is designed to deliver a peak current of 45--50 MA with a 4--5 {micro}s risetime. The Marx modules are designed to be reconfigured to a 480-kV configuration, if needed, for opening switch development. The bank is resistively damped to limit fault currents and capacitor voltage reversal. The system is configured for very low-inductance operation (total inductance {approximately} 10 nH) to rapidly implode heavy liner loads. An experimental program for testing and certifying prototype components is currently underway. For many applications the Atlas liner will be nominal 70g aluminum cylinder. Using composite inner layers and a variety of interior target designs, a wide variety of experiments in {approximately}cm{sup 3} volumes may be performed. These include shock compression experiments up to {approximately} 3 TPa (30 Mbar), quasi-adiabatic compressions up to 6-fold compression and pressures above 10 TPa, hydrodynamic instability studies in nonlinear and turbulent regimes over multi-cm propagation lengths, experiments with dense plasmas in the so-called high-gamma regime, studies of materials response at very high strains and strain rates, and materials studies in ultrahigh magnetic fields (above 10{sup 3} T).

  8. Future Experiments in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Rene Bellwied

    2007-10-22

    The measurements at RHIC have revealed a new state of matter, which needs to be further characterized in order to better understand its implications for the early evolution of the universe and QCD. I will show that, in the near future, complementary key measurements can be performed at RHIC, LHC, and FAIR. I will focus on results than can be obtained using identified particles, a probe which has been the basis for this conference over the past three decades. The sophisticated detectors, built and planned, for all three accelerator facilities enable us to measure leptons, photons, muons as well as hadrons and resonances of all flavors almost equally well, which makes these experiments unprecedented precision tools for the comprehensive understanding of the physics of the early universe.

  9. Relativistic Heavy Ion Collider Funding Agencies

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

    Promotion of Science National Council for Scientific and Technological Development, Brazil Research Supporting Foundation of the State of Sao Paulo, Brazil National Natural...

  10. Observables from a relativistic hydro solution

    E-Print Network [OSTI]

    Csanad, Mate

    2009-01-01

    In the last several years it has been revealed that the matter produced in the collisions of the Relativistic Heavy Ion Collider (RHIC) is a nearly perfect fluid, i.e. it can be described with perfect fluid hydrodynamics. There was a long search for exact hydrodynamic models (solutions of the partial differential equations of hydrodynamics) and several models proved to be applicable. There are 1+3 dimensional models, as well as relativistic models - but no 1+3 dimensional and relativistic model has been tested yet. In this paper we extract observables from the relativistic, ellipsoidally symmetric model of Csorgo et al. We calculate momentum distribution, elliptic flow and correlation radii and compare them to RHIC data.

  11. Summary of Heavy Ion Theory

    E-Print Network [OSTI]

    Sean Gavin

    1994-09-20

    Can we study hot QCD using nuclear collisions? Can we learn about metallic hydrogen from the impact of comet Shoemaker-Levy 9 on Jupiter? The answer to both questions may surprise you! I summarize progress in relativistic heavy ion theory reported at DPF `94 in the parallel sessions.

  12. Heavy-Ion Physics with CMS

    E-Print Network [OSTI]

    Aneta Iordanova

    2008-06-06

    This article presents a brief overview of the CMS experiment capabilities to study the hot and dense matter created in relativistic heavy-ion collisions. The CERN Large Hadron Collider will provide collisions of Pb nuclei at 5.5 TeV per nucleon. The CMS heavy ion group has developed a plethora of physics analyses addressing many important aspects of heavy-ion physics in preparation for a competitive and successful program.

  13. Open heavy flavor production at RHIC

    E-Print Network [OSTI]

    A. A. P. Suaide

    2007-02-16

    The study of heavy flavor production in relativistic heavy ion collisions is an extreme experimental challenge but provides important information on the properties of the Quark-Gluon Plasma (QGP) created in Au+Au collisions at RHIC. Heavy-quarks are believed to be produced in the initial stages of the collision, and are essential on the understanding of parton energy loss in the dense medium created in such environment. Moreover, heavy-quarks can help to investigate fundamental properties of QCD in elementary p+p collisions. In this work we review recent results on heavy flavor production and their interaction with the hot and dense medium at RHIC.

  14. Formation of Superdense Hadronic Matter in High-Energy Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Li, Ba0-An; Ko, Che Ming.

    1995-01-01

    We present the detail of a newly developed relativistic transport model (ART 1.0) for high energy heavy-ion collisions. Using this model, we first study the general collision dynamics between heavy ions at the AGS energies. ...

  15. BNL ATLAS Grid Computing

    ScienceCinema (OSTI)

    Michael Ernst

    2010-01-08

    As the sole Tier-1 computing facility for ATLAS in the United States and the largest ATLAS computing center worldwide Brookhaven provides a large portion of the overall computing resources for U.S. collaborators and serves as the central hub for storing,

  16. “Ripples” on a relativistically expanding fluid

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

    Shi, Shuzhe; Liao, Jinfeng; Zhuang, Pengfei

    2014-12-29

    Recent studies have shown that fluctuations of various types play important roles in the evolution of the fireball created in relativistic heavy ion collisions and bear many phenomenological consequences for experimental observables. In addition, the bulk dynamics of the fireball is well described by relativistic hydrodynamic expansion and the fluctuations on top of such expanding background can be studied within the linearized hydrodynamic framework. In this paper we present complete and analytic sound wave solutions on top of both Bjorken flow and Hubble flow backgrounds.

  17. Search for long-lived, heavy particles in final states with a muon and multi-track displaced vertex in proton–proton collisions at ?s =7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    ATLAS Collaboration

    Many extensions of the Standard Model posit the existence of heavy particles with long lifetimes. In this Letter, results are presented of a search for events containing one or more such particles, which decay at a significant ...

  18. Automated Transportation Logistics and Analysis System (ATLAS...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Packaging and Transportation Automated Transportation Logistics and Analysis System (ATLAS) Automated Transportation Logistics and Analysis System (ATLAS) The Department of...

  19. Top Physics at ATLAS

    E-Print Network [OSTI]

    Marcello Barisonzi

    2005-08-02

    The Large Hadron Collider LHC is a top quark factory: due to its high design luminosity, LHC will produce about 200 millions of top quarks per year of operation. The large amount of data will allow to study with great precision the properties of the top quark, most notably cross-section, mass and spin. The Top Physics Working Group has been set up at the ATLAS experiment, to evaluate the precision reach of physics measurements in the top sector, and to study the systematic effects of the ATLAS detector on such measurements. This reports give an overview of the main activities of the ATLAS Top Physics Working Group in 2004.

  20. ATLAS Metadata Task Force

    SciTech Connect (OSTI)

    ATLAS Collaboration; Costanzo, D.; Cranshaw, J.; Gadomski, S.; Jezequel, S.; Klimentov, A.; Lehmann Miotto, G.; Malon, D.; Mornacchi, G.; Nemethy, P.; Pauly, T.; von der Schmitt, H.; Barberis, D.; Gianotti, F.; Hinchliffe, I.; Mapelli, L.; Quarrie, D.; Stapnes, S.

    2007-04-04

    This document provides an overview of the metadata, which are needed to characterizeATLAS event data at different levels (a complete run, data streams within a run, luminosity blocks within a run, individual events).

  1. Search for Pair Production of a Heavy Up-Type Quark Decaying to a W Boson and a b Quark in the lepton+jets Channel with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for production of a heavy up-type quark (t?) together with its antiparticle, assuming subsequent decay to a W boson and a b quark, t?t? ?-->W[superscript+]bW[superscript -]b? . The search is based on ...

  2. Search for resonant WZ production in the WZ?l?l?l? channel in ?(s)=7??TeV pp collisions with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A generic search is presented for a heavy particle decaying to WZ??????? (?, ??=e, ?) final states. The data were recorded by the ATLAS detector in ?s=7??TeV pp collisions at the Large Hadron Collider and correspond to an ...

  3. Report to users of ATLAS

    SciTech Connect (OSTI)

    Ahmad, I.; Glagola, B. [eds.

    1997-03-01

    This report covers the following topics: (1) status of the ATLAS accelerator; (2) progress in R and D towards a proposal for a National ISOL Facility; (3) highlights of recent research at ATLAS; (4) the move of gammasphere from LBNL to ANL; (5) Accelerator Target Development laboratory; (6) Program Advisory Committee; (7) ATLAS User Group Executive Committee; and (8) ATLAS user handbook available in the World Wide Web. A brief summary is given for each topic.

  4. Relativistic Remnants of Non-Relativistic Electrons

    E-Print Network [OSTI]

    Taro Kashiwa; Taisuke Yamaguchi

    2014-10-09

    Electrons obeying the Dirac equation are investigated under the non-relativistic $c \\mapsto \\infty$ limit. General solutions are given by derivatives of the relativistic invariant functions whose forms are different in the time- and the space-like region, yielding the delta function of $(ct)^2 - x^2$. This light-cone singularity does survive to show that the charge and the current density of electrons travel with the speed of light in spite of their massiveness.

  5. Relativistic Guiding Center Equations

    SciTech Connect (OSTI)

    White, R. B.; Gobbin, M.

    2014-10-01

    In toroidal fusion devices it is relatively easy that electrons achieve relativistic velocities, so to simulate runaway electrons and other high energy phenomena a nonrelativistic guiding center formalism is not sufficient. Relativistic guiding center equations including flute mode time dependent field perturbations are derived. The same variables as used in a previous nonrelativistic guiding center code are adopted, so that a straightforward modifications of those equations can produce a relativistic version.

  6. The relativistic glider

    E-Print Network [OSTI]

    Eduardo Gueron; Ricardo A. Mosna

    2007-04-11

    We present a purely relativistic effect according to which asymmetric oscillations of a quasi-rigid body slow down or accelerate its fall in a gravitational background.

  7. Directed Relativistic Blast Wave

    E-Print Network [OSTI]

    Andrei Gruzinov

    2007-04-23

    A spherically symmetrical ultra-relativistic blast wave is not an attractor of a generic asymmetric explosion. Spherical symmetry is reached only by the time the blast wave slows down to non-relativistic velocities, when the Sedov-Taylor-von Neumann attractor solution sets in. We show however, that a directed relativistic explosion, with the explosion momentum close to the explosion energy, produces a blast wave with a universal intermediate asymptotic -- a selfsimilar directed ultra-relativistic blast wave. This universality might be of interest for the astrophysics of gamma-ray burst afterglows.

  8. Atlas Finding Aid Contents/Index

    E-Print Network [OSTI]

    Ward, Karen

    Atlas Finding Aid Contents/Index A (1) City & State Atlas A (2) Astronomy Atlas A (3) U.S. Atlas A (4) Water Atlas A (5) South America & Central America A (6) Africa, Asia, &, Antarctica A (7) Mexico) SAN ANTONIO QUICK FINDER MAPS F 1373 .B46 F4 1990 33. A (1) SURFACE WATER RESOURCES OF TEXAS MAPS G

  9. General Relativistic Radiative Transfer and GeneralRelativistic...

    Office of Scientific and Technical Information (OSTI)

    systems using a fully general relativistic radiative transfer formulation, with flow structures obtained by general relativistic magneto-hydrodynamic simulations. We consider...

  10. ATLAS TDAQ System Administration:

    E-Print Network [OSTI]

    Lee, Christopher Jon; The ATLAS collaboration; Bogdanchikov, Alexander; Ballestrero, Sergio; Contescu, Alexandru Cristian; Dubrov, Sergei; Fazio, Daniel; Korol, Aleksandr; Scannicchio, Diana; Twomey, Matthew Shaun; Voronkov, Artem

    2015-01-01

    The ATLAS Trigger and Data Acquisition (TDAQ) system is responsible for the online processing of live data, streaming from the ATLAS experiment at the Large Hadron Collider (LHC) at CERN. The online farm is composed of ?3000 servers, processing the data readout from ?100 million detector channels through multiple trigger levels. During the two years of the first Long Shutdown (LS1) there has been a tremendous amount of work done by the ATLAS TDAQ System Administrators, implementing numerous new software applications, upgrading the OS and the hardware, changing some design philosophies and exploiting the High Level Trigger farm with different purposes. During the data taking only critical security updates are applied and broken hardware is replaced to ensure a stable operational environment. The LS1 provided an excellent opportunity to look into new technologies and applications that would help to improve and streamline the daily tasks of not only the System Administrators, but also of the scientists who wil...

  11. Gluon contribution to open heavy meson production in heavy-ion collisions

    E-Print Network [OSTI]

    Cao, Shanshan; Wang, Xin-Nian

    2015-01-01

    A sizable contribution to heavy quark production in high-energy hadronic and nuclear collisions comes from heavy quark-antiquark pair production from gluon splitting during the parton shower evolution. We investigate the effect of gluon-medium interaction on open heavy flavor spectra in ultra-relativistic heavy-ion collisions. The interaction of hard gluons and heavy quarks with the hot QCD medium is simulated utilizing a Langevin transport model that simultaneously incorporates contributions from collisional and radiative processes. It is found that while the gluon splitting channel has quite important contribution to single D meson production cross section, its influence on the final heavy meson nuclear modification turns out to be quite modest due to the short average lifetime of hard gluons before splitting to heavy quark pairs during the evolution and propagation of the parton shower.

  12. Improving ATLAS reprocessing software

    E-Print Network [OSTI]

    Novak, Tadej

    2014-01-01

    For my CERN Summer Student programme I have been working with ATLAS reprocessing group. Data taken at ATLAS experiment is not only processed after being taken, but is also reprocessed multiple times afterwards. This allows applying new alignments, calibration of detector and using improved or faster algorithms. Reprocessing is usually done in campaigns for different periods of data or for different interest groups. The idea of my project was to simplify the definition of tasks and monitoring of their progress. I created a LIST configuration files generator script in Python and a monitoring webpage for tracking current reprocessing tasks.

  13. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiationFutureATLAS

  14. Relativistic Laser-Matter Interactions

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

    Relativistic Laser-Matter Interactions Relativistic Laser-Matter Interactions Enabling the next generation of intense particle accelerators Contact Juan Fernandez (505) 667-6575...

  15. Relativistic Quaternionic Wave Equation II

    E-Print Network [OSTI]

    Schwartz, Charles

    2007-01-01

    Relativistic quaternionic wave equation. II J. Math. Phys.Relativistic quaternionic wave equation. II Charles Schwartzcomponent quaternionic wave equation recently introduced. A

  16. Heavy Quark Photoproduction in Ultra-peripheral Heavy Ion Collisions

    E-Print Network [OSTI]

    Spencer R. Klein; Joakim Nystrand; Ramona Vogt

    2002-08-09

    Heavy quarks are copiously produced in ultra-peripheral heavy ion collisions. In the strong electromagnetic fields, c c-bar and b b-bar are produced by photonuclear and two-photon interactions; hadroproduction can occur in grazing interactions. We present the total cross sections, quark transverse momentum and rapidity distributions, as well as the Q Q-bar invariant mass spectra from the three production channels. We consider AA and pA collisions at the Relativistic Heavy Ion Collider and Large Hadron Collider. We discuss techniques for separating the three processes and describe how the AA to pA production ratios might be measured accurately enough to study nuclear shadowing.

  17. Wheat Diseases Atlas

    E-Print Network [OSTI]

    McCoy, Norman L.; Berry, Robert W.

    1982-01-01

    to wheat producers over the state on whose farms demonstrations have been conducted and pic tures for this publication were made. WhEAT DisEASES ATLAs Norman L. McCoy and Robert W Berry* INTRODUCTION Wheat diseases have caused untold human suffer ing...

  18. Operationalization of Relativistic Motion

    E-Print Network [OSTI]

    Bruno Hartmann

    2015-01-08

    We apply the Helmholtz program of basic measurements to relativistic motion. We define a spatiotemporal order by practical comparison: "longer than" if one object or process covers the other. To express its value also numerically (how many times more) we cover them by a locally regular grid of light clocks. We define basic measures from physical operations. Interrelation of measurement operations by different observers reveals a genetic derivation of formal Lorentz transformation. Operationally impracticable configurations for accelerating observers clarify the way out of apparent Twin paradox. From simple measurement-methodical principles - without mathematical presuppositions - we derive all equations of relativistic Kinematics (and next same for classical and relativistic Dynamics).

  19. BioFuels Atlas Presentation

    Office of Energy Efficiency and Renewable Energy (EERE)

    Kristi Moriarity's presentation on NREL's BioFuels Atlas from the May 12, 2011, Clean Cities and Biomass Program State webinar.

  20. Higgs boson search at ATLAS

    E-Print Network [OSTI]

    Scott Snyder; for the ATLAS Collaboration

    2012-09-04

    The status of the ATLAS Higgs boson search using about 5 fb^-1 of data recorded in 2011 is summarized. Proceedings from Physics at the LHC 2012 (Vancouver).

  1. Carbon Sequestration Atlas IV Video

    ScienceCinema (OSTI)

    Rodosta, Traci

    2014-06-27

    The Carbon Sequestration Atlas is a collection of all the storage sites of CO2 such as, petroleum, natural gas, coal, and oil shale.

  2. Carbon Sequestration Atlas IV Video

    SciTech Connect (OSTI)

    Rodosta, Traci

    2013-04-19

    The Carbon Sequestration Atlas is a collection of all the storage sites of CO2 such as, petroleum, natural gas, coal, and oil shale.

  3. RELATIVISTIC NUCLEAR COLLISIONS: THEORY

    E-Print Network [OSTI]

    Gyulassy, M.

    2010-01-01

    Effects in Relativistic Nuclear Collisions", Preprint LBL-Pion Interferometry of Nuclear Collisions. 18.1 M.Gyulassy,was supported by the Office of Nuclear Physics of the U.S.

  4. Relativistic Nuclear Collisions

    E-Print Network [OSTI]

    Reinhard Stock

    2009-07-29

    A comprehensive introduction is given to the field of relativistic nuclear collisions, and the phase diagram of strongly interacting matter. The content of this complex of reviews is shown.

  5. Relativistic viscoelastic fluid mechanics

    E-Print Network [OSTI]

    Masafumi Fukuma; Yuho Sakatani

    2011-09-01

    A detailed study is carried out for the relativistic theory of viscoelasticity which was recently constructed on the basis of Onsager's linear nonequilibrium thermodynamics. After rederiving the theory using a local argument with the entropy current, we show that this theory universally reduces to the standard relativistic Navier-Stokes fluid mechanics in the long time limit. Since effects of elasticity are taken into account, the dynamics at short time scales is modified from that given by the Navier-Stokes equations, so that acausal problems intrinsic to relativistic Navier-Stokes fluids are significantly remedied. We in particular show that the wave equations for the propagation of disturbance around a hydrostatic equilibrium in Minkowski spacetime become symmetric hyperbolic for some range of parameters, so that the model is free of acausality problems. This observation suggests that the relativistic viscoelastic model with such parameters can be regarded as a causal completion of relativistic Navier-Stokes fluid mechanics. By adjusting parameters to various values, this theory can treat a wide variety of materials including elastic materials, Maxwell materials, Kelvin-Voigt materials, and (a nonlinearly generalized version of) simplified Israel-Stewart fluids, and thus we expect the theory to be the most universal description of single-component relativistic continuum materials. We also show that the presence of strains and the corresponding change in temperature are naturally unified through the Tolman law in a generally covariant description of continuum mechanics.

  6. WESTCARB Carbon Atlas

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

    The West Coast Regional Carbon Sequestration Partnership (known as WESTCARB) was established in Fall 2003. It is one of seven research partnerships co-funded by DOE to characterize regional carbon sequestration opportunities and conduct pilot-scale validation tests. The California Energy Commission manages WESTCARB and is a major co-funder. WESTCARB is characterizing the extent and capacity of geologic formations capable of storing CO2, known as sinks. Results are entered into a geographic information system (GIS) database, along with the location of major CO2-emitting point sources in each of the six WESTCARB states, enabling researchers and the public to gauge the proximity of candidate CO2 storage sites to emission sources and the feasibility of linking them via pipelines. Specifically, the WESTCARB GIS database (also known as the carbon atlas) stores layers of geologic information about potential underground storage sites, such as porosity and nearby fault-lines and aquifers. Researchers use these data, along with interpreted geophysical data and available oil and gas well logs to estimate the region's potential geologic storage capacity. The database also depicts existing pipeline routes and rights-of-way and lands that could be off-limits, which can aid the development of a regional carbon management strategy. The WESTCARB Carbon Atlas, which is accessible to the public, provides a resource for public discourse on practical solutions for regional CO2 management. A key WESTCARB partner, the Utah Automated Geographic Reference Center, has developed data serving procedures to enable the WESTCARB Carbon Atlas to be integrated with those from other regional partnerships, thereby supporting the U.S. Department of Energy's national carbon atlas, NATCARB

  7. Relativistic Point Coupling Model for Vibrational Excitations in the Continuum

    SciTech Connect (OSTI)

    Ring, P.; Daoutidis, J.; Litvinova, E.; Niksic, T.; Paar, N.; Vretenar, D.

    2009-08-26

    An implementation of the relativistic random phase approximation with the proper treatment of the continuum has been developed for the relativistic point coupling model and applied to investigate collective excitations in spherical nuclei. The results are compared with the spectral implementation of the same model. In heavy nuclei, where the escape width is negligible, we find an excellent agreement between both methods in the region of giant resonance and some discrepancies in the region of low-lying pygmy resonance. The differences are more pronounced in light nuclei due to the larger values of the escape widths.

  8. Heavy-flavor production in heavy-ion collisions and implications for the properties of hot QCD matter

    E-Print Network [OSTI]

    R. Averbeck

    2015-05-14

    Hadrons carrying open heavy flavor, i.e. single charm or bottom quarks, are among the key diagnostic tools available today for the hot and dense state of strongly interacting matter which is produced in collisions of heavy atomic nuclei at ultra-relativistic energies. First systematic heavy-flavor measurements in nucleus-nucleus collisions and the reference proton-proton system at Brookhaven National Laboratory's (BNL) Relativistic Heavy Ion Collider (RHIC) have led to tantalizing results. These studies are now continued and extended at RHIC and at CERN's Large Hadron Collider (LHC), where considerably higher collision energies are available. This review focuses on experimental results on open heavy-flavor observables at RHIC and the LHC published until July 2012. Yields of heavy-flavor hadrons and their decay products, their transverse momentum and rapidity distributions, as well as their azimuthal distributions with respect to the reaction plane in heavy-ion collisions are investigated. Various theoretical approaches are confronted with the data and implications for the properties of the hot and dense medium produced in ultra-relativistic heavy-ion collisions are discussed.

  9. Measurements of Heavy Flavor and Di-electron Production at STAR

    E-Print Network [OSTI]

    Gang Wang

    2012-01-20

    Heavy quarks are produced early in the relativistic heavy ion collisions, and provide an excellent probe into the hot and dense nuclear matter created at RHIC. In these proceedings, we will discuss recent STAR measurements of heavy flavor production, to investigate the heavy quark interaction with the medium. Electromagnetic probes, such as electrons, provide information on the various stages of the medium evolution without modification by final stage interactions. Di-electron production measurements by STAR will also be discussed.

  10. Antikaon flow in heavy-ion collisions: Effects of absorption and mean-field potential 

    E-Print Network [OSTI]

    Li, GQ; Ko, Che Ming.

    1996-01-01

    We study antikaon flow in heavy-ion collisions at SIS energies based on the relativistic transport model (RVUU 1.0). The production of antikaons from both baryon-baryon and pion-baryon collisions are included. Taking into ...

  11. Studies of high transverse momentum phenomena in heavy ion collisions using the PHOBOS detector

    E-Print Network [OSTI]

    Wenger, Edward (Edward Allen)

    2008-01-01

    The use of high-pT particles as calibrated probes has proven to be an effective tool for understanding the properties of the system produced in relativistic heavy ion collisions. In this thesis, two such measurements are ...

  12. The relativistic Pauli equation

    E-Print Network [OSTI]

    David Delphenich

    2012-07-24

    After discussing the way that C2 and the algebra of complex 2x2 matrices can be used for the representation of both non-relativistic rotations and Lorentz transformations, we show that Dirac bispinors can be more advantageously represented as 2x2 complex matrices. One can then give the Dirac equation a form for such matrix-valued wave functions that no longer necessitates the introduction of gamma matrices or a choice for their representation. The minimally-coupled Dirac equation for a charged spinning particle in an external electromagnetic field then implies a second order equation in the matrix-valued wave functions that is of Klein-Gordon type and represents the relativistic analogue of the Pauli equation. We conclude by presenting the Lagrangian form for the relativistic Pauli equation.

  13. Relativistic Positioning Systems

    E-Print Network [OSTI]

    Bartolomé Coll

    2006-02-01

    The theory of relativistic {\\em location systems} is sketched. An interesting class of these systems is that of relativistic {\\em positioning systems,} which consists in sets of four clocks broadcasting their proper time. Among them, the more important ones are the {\\em auto-located positioning systems,} in which every clock broadcasts not only its proper time but the proper times that it receives from the other three. At this level, no reference to any exterior system (the Earth surface, for example) and no synchronization are needed. Some properties are presented. In the SYPOR project, such a structure is proposed, eventually anchored to a classical reference system on the Earth surface, as the best relativistic structure for Global Navigation Satellite Systems.

  14. Argonne Physics Division - ATLAS

    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 OutreachProductswsicloudwsiclouddenDVA N C E D B L O O D SFederal8823 RevisionApril 22-23, 2011 ATLAS PAC Meeting

  15. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS Program Advisory Committee

  16. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS Program Advisory

  17. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS Program AdvisoryExperiment

  18. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS Program

  19. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiation Safety at

  20. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiation Safety

  1. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiation Safety2

  2. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiation Safety25

  3. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiation

  4. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS ProgramRadiationFuture

  5. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLAS

  6. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLASExperimentalThe ATLAS User

  7. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLASExperimentalThe ATLAS

  8. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLASExperimentalTheATLAS USERS

  9. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneThe ATLASExperimentalTheATLAS

  10. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneTheRegistered2014 ATLAS User’s

  11. Argonne Physics Division - ATLAS

    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 Room News Publications TraditionalWithAntiferromagnetic ArgonneTheRegistered2014 ATLAS

  12. Review of QCD, Quark-Gluon Plasma, Heavy Quark Hybrids, and Heavy Quark State production in p-p and A-A collisions

    E-Print Network [OSTI]

    Leonard S. Kisslinger; Debasish Das

    2015-05-12

    This is a review of the Quantum Chrodynamics Cosmological Phase Transition, the Quark-Gluon Plasma, and the detection of the Quark-Gluon Plasma via RHIC(Relativistic Heavy Ion Collisions) production of heavy quark states using the mixed hybrid theory for the $\\Psi(2S)$ and $\\Upsilon(3S)$ states.

  13. Heavy baryons in the large Nc limit

    E-Print Network [OSTI]

    Albertus, C; Fernando, I P; Goity, J L

    2015-01-01

    It is shown that in the large Nc limit heavy baryon masses can be estimated quantitatively in a 1/Nc expansion using the Hartree approximation. The results are compared with available lattice calculations for different values of the ratio between the square root of the string tension and the heavy quark mass tension independent of Nc. Using a potential adjusted to agree with the one obtained in lattice QCD, a variational analysis of the ground state spin averaged baryon mass is performed using Gaussian Hartree wave functions. Relativistic corrections through the quark kinetic energy are included. The results provide good estimates for the first sub-leading in 1/Nc corrections.

  14. Heavy baryons in the large Nc limit

    E-Print Network [OSTI]

    C. Albertus; E. Ruiz Arriola; I. P. Fernando; J. L. Goity

    2015-07-16

    It is shown that in the large Nc limit heavy baryon masses can be estimated quantitatively in a 1/Nc expansion using the Hartree approximation. The results are compared with available lattice calculations for different values of the ratio between the square root of the string tension and the heavy quark mass tension independent of Nc. Using a potential adjusted to agree with the one obtained in lattice QCD, a variational analysis of the ground state spin averaged baryon mass is performed using Gaussian Hartree wave functions. Relativistic corrections through the quark kinetic energy are included. The results provide good estimates for the first sub-leading in 1/Nc corrections.

  15. ATLAS Boosted Object Tagging

    E-Print Network [OSTI]

    Leblanc, Matthew Edgar; The ATLAS collaboration

    2015-01-01

    Tagging boosted top quarks with the ATLAS detector at sqrt(s)=8 TeV and sqrt(s)=13 TeV Different methods to identify high-pT top quarks based on substructure analyses are studied using pp collision data and MC simulations at sqrt(s)=8 TeV. An enriched ttbar sample is used to measure the top selection efficiency in data for substructure-based taggers as well as the HEPTopTagger and Shower Deconstruction algorithms. An enriched QCD sample is used to measure the misidentification rate for these algorithms. In addition, MC simulations at sqrt(s)=13 TeV with 2015 data-taking conditions are used to determine substructure-based taggers and their systematic uncertainties for use by early data analyses. Data/MC comparisons of these variables with early data are also shown. Tagging boosted Higgs bosons with the ATLAS detector at sqrt(s)=8 TeV and sqrt(s)=13 TeV The identification of boosted Higgs bosons decaying to a pair of b-quarks is studied using pp collision data at sqrt(s)=8 TeV and MC simulations at sqrt(s)=8 Te...

  16. Transverse stability of relativistic two-component jets

    E-Print Network [OSTI]

    Z. Meliani; R. Keppens

    2007-09-24

    Context: Astrophysical jets from various sources seem to be stratified, with a fast inner jet and a slower outer jet. As it is likely that the launching mechanism for each component is different, their interface will develop differential rotation, while the outer jet radius represents a second interface where disruptions may occur. Aims: We explore the stability of stratified, rotating, relativistic two-component jets, in turn embedded in static interstellar medium. Methods: In a grid-adaptive relativistic hydrodynamic simulation with the AMRVAC code, the non-linear azimuthal stability of two-component relativistic jets is investigated. We simulate until multiple inner jet rotations have been completed. Results: We find evidence for the development of an extended shear flow layer between the two jet components, resulting from the growth of a body mode in the inner jet, Kelvin-Helmholtz surface modes at their original interface, and their nonlinear interaction. Both wave modes are excited by acoustic waves which are reflected between the symmetry axis and the interface of the two jet components. Their interaction induces the growth of near stationary, counterrotating vortices at the outer edge of the shear flow layer. The presence of a heavy external jet allows to slow down their further development, and maintain a collimated flow. At the outer jet boundary, small-scale Rayleigh-Taylor instabilities develop, without disrupting the jet configuration. Conclusion: We demonstrate that the cross-section of two-component relativistic jets, with a heavy, cold outer jet, is non-linearly stable.

  17. Relativistic effects on plasma expansion

    SciTech Connect (OSTI)

    Benkhelifa, El-Amine; Djebli, Mourad, E-mail: mdjebli@usthb.dz [USTHB, Faculty of Physics, Theoretical Physics Laboratory, B.P. 32 Bab-Ezzouar, 16079 Algiers (Algeria)

    2014-07-15

    The expansion of electron-ion plasma is studied through a fully relativistic multi-fluids plasma model which includes thermal pressure, ambipolar electrostatic potential, and internal energy conversion. Numerical investigation, based on quasi-neutral assumption, is performed for three different regimes: nonrelativistic, weakly relativistic, and relativistic. Ions' front in weakly relativistic regime exhibits spiky structure associated with a break-down of quasi-neutrality at the expanding front. In the relativistic regime, ion velocity is found to reach a saturation limit which occurs at earlier stages of the expansion. This limit is enhanced by higher electron velocity.

  18. Characterization of Relativistic MHD Turbulence

    E-Print Network [OSTI]

    Garrison, David

    2015-01-01

    The objective of this work is to understand if and how the characteristics of relativistic MHD turbulence may differ from those of nonrelativistic MHD turbulence. We accomplish this by studying the invariants in the relativistic case and comparing them to what we know of nonrelativistic turbulence. Although much work has been done to understand the dynamics of nonrelativistic systems (mostly for ideal incompressible fluids), there is minimal literature explicitly describing the dynamics of relativistic MHD turbulence. Many authors simply assume that relativistic turbulence has the same invariants and obeys the same inverse energy cascade as non-relativistic systems.

  19. BioFuels Atlas (Presentation)

    SciTech Connect (OSTI)

    Moriarty, K.

    2011-02-01

    Presentation for biennial merit review of Biofuels Atlas, a first-pass visualization tool that allows users to explore the potential of biomass-to-biofuels conversions at various locations and scales.

  20. Search for a Standard Model Higgs Boson in the H?ZZ??+?-??? Decay Channel with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for a heavy standard model Higgs boson decaying via H?ZZ??+?-??? , where ?=e, ?, is presented. It is based on proton-proton collision data at ?s=7??TeV, collected by the ATLAS experiment at the LHC in the first ...

  1. Class Generation for Numerical Wind Atlases

    E-Print Network [OSTI]

    Class Generation for Numerical Wind Atlases Risø National Laboratory Wind Energy Department Constructing a Numerical Wind Atlas 5 2.1 Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.4 The existing procedure at Risø . . . . . . . . . . . . . . . . . . . 13 3 Representing a Wind

  2. Consumer Energy Atlas

    SciTech Connect (OSTI)

    Not Available

    1980-06-01

    This first edition of the Atlas provides, in reference form, a central source of information to consumers on key contacts concerned with energy in the US. Energy consumers need information appropriate to local climates and characteristics - best provided by state and local governments. The Department of Energy recognizes the authority of state and local governments to manage energy programs on their own. Therefore, emphasis has been given to government organizations on both the national and state level that influence, formulate, or administer policies affecting energy production, distribution, and use, or that provide information of interest to consumers and non-specialists. In addition, hundreds of non-government energy-related membership organizations, industry trade associations, and energy publications are included.

  3. Quarkonium production at ATLAS

    E-Print Network [OSTI]

    Darren D Price

    2012-01-24

    The production of quarkonium is an important testing ground for QCD calculations. The J/\\psi\\ and \\Upsilon\\ production cross-sections are measured in proton-proton collisions at a centre-of-mass energy of 7~TeV with the ATLAS detector at the LHC. Differential cross-sections are presented as a function of transverse momentum and rapidity. The fraction of J/\\psi\\ produced in B-hadron decays is also measured and the differential cross-sections of prompt and non-prompt J/\\psi\\ production determined separately. Measurements of the fiducial production cross-section of the \\Upsilon(1S) and observation of the \\chi_{c,bJ} states are also discussed.

  4. b-Tagging Algorithms and their Performance at ATLAS

    E-Print Network [OSTI]

    Marc Lehmacher

    2008-11-04

    The ability to identify jets containing B hadrons is important for the high-pT physics program of a general-purpose experiment such as ATLAS. b-tagging is in particular useful for selecting very pure top quark samples, for studying standard model or supersymmetric Higgs bosons which couple preferably to heavy objects, for vetoing backgrounds for several physics channels and finally for searching for new physics beyond the standard model like supersymmetric particles or heavy gauge bosons. After a review of the algorithms used to identify b-jets, their anticipated performance is discussed as well as the impact of selected critical ingredients such as residual misalignments in the tracker. The prospects to measure the b-tagging performance in the first few hundreds pb-1 of data with di-jet events as well as ttbar events are presented. Finally three different physics use cases of b-tagging are summarised.

  5. Azimuthal anisotropy in high-energy heavy-ion collisions at RHIC energies

    E-Print Network [OSTI]

    ShinIchi Esumi

    2004-05-19

    Directed and elliptic event anisotropy parameters measured in the experiments at relativistic heavy-ion collider are presented. The possible origin of the measured elliptic anisotropy parameter $v_2$ and its sensitivity to the early phase of the high-energy heavy-ion collisions are discussed.

  6. Extensivity and Relativistic Thermodynamics

    E-Print Network [OSTI]

    J. Dunning-Davies

    2007-06-27

    The mathematical properties associated with the widely accepted concept of the extensivity of many of the common thermodynamic variables are examined and some of their consequences considered. The possible conflict between some of these and currently accepted results of special relativistic thermodynamics is highlighted. Although several questions are raised, answers are not advanced as this seems an area demanding calm, widespread reflection which could conceivably lead to radical revision of part, or parts, of theoretical physics.

  7. Relativistic mechanism of superconductivity

    E-Print Network [OSTI]

    H. Y. Cui

    2002-12-17

    According to the theory of relativity, the relativistic Coulomb's force between an electron pair is composed of two parts, the main part is repulsive, while the rest part can be attractive in certain situations. Thus the relativistic attraction of an electron pair provides an insight into the mechanism of superconductivity. In superconductor, there are, probably at least, two kinds of collective motions which can eliminate the repulsion between two electrons and let the attraction being dominant, the first is the combination of lattice and electron gas, accounting for traditional superconductivity; the second is the electron gas themselves, accounting for high $T_c$ superconductivity. In usual materials, there is a good balance between the repulsion and attraction of an electron pair, the electrons are regarded as free electrons so that Fermi gas theory plays very well. But in some materials, when the repulsion dominates electron pairs, the electron gas will has a behavior opposite to superconductivity. In the present paper the superconducting states are discussed in terms of relativistic quantum theory in details, some significant results are obtained including quantized magnetic flux, London equation, Meissner effect and Josephson effect.

  8. WORLD OCEAN ATLAS 2013 Product Documentation

    E-Print Network [OSTI]

    WORLD OCEAN ATLAS 2013 Product Documentation Ocean Climate Laboratory NODC / NESDIS / NOAA Silver: World Ocean Atlas 2013 Product Documentation. T. Boyer, Ed.; A. Mishonov, Technical Ed.; 14 pp such as mixed layer depth. Upon publishing Climatological Atlas of the World Ocean in 1982, he distributed

  9. Flow, spectra and HBT radii in heavy-ion collisions

    E-Print Network [OSTI]

    Piotr Bozek; Iwona Wyskiel

    2009-09-12

    The expansion of the fireball created in relativistic heavy ion collisions is described using the 3+1D hydrodynamical model. Experimentally observed transverse momentum spectra at different rapdities, elliptic flow and HBT correlations of produced particles can be reproduced. We give estimates of shear viscosity corrections at freeze-out, which we find important only for the elliptic flow coefficient.

  10. Antiflow of kaons in relativistic heavy ion collisions 

    E-Print Network [OSTI]

    Pal, S.; Ko, Che Ming; Lin, ZW; Zhang, B.

    2000-01-01

    processes, the kaon production cross sections in- volving resonances are assumed to be the same as those for Antiflow of kaons in relativisti Subrata Pal,1 C. M. Ko,1 Ziwe 1Cyclotron Institute and Physics Department, Texas 2Department of Chemistry... collisions we investigate in this Rapid Com- munication if the appreciable kaon antiflow can be explained by the repulsive kaon potential in dense nuclear matter. We ?2000 The American Physical Society1 RAPID COMMUNICATIONS SUBRATA PAL, C. M. KO, ZIWEI...

  11. Multiphase transport model for relativistic heavy ion collisions 

    E-Print Network [OSTI]

    Lin, ZW; Ko, Che Ming; Li, Ba; Zhang, B.; Pal, S.

    2005-01-01

    &M University, College Station, Texas 77843, USA Bao-An Li and Bin Zhang Department of Chemistry and Physics, Arkansas State University, State University, Arkansas 72467, USA Subrata Pal Department of Physics, Michigan State University, East Lansing...-2813/2005/72(6)/064901(29)/$23.00 064901-1 2005 The American Physical Society LIN, KO, LI, ZHANG, AND PAL PHYSICAL REVIEW C 72, 064901 (2005) strings and minijets dominate the initial energy production and effects from final-state interactions are important. For the initial conditions...

  12. Isospin fluctuations in QCD and relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Prakash, M.; Rapp, Ralf; Wambach, J.; Zahed, I.

    2002-01-01

    was accomplished by varying model particle spacing, sub-particle scale (SPS) turbulence inclusion in the conservation of momentum equation, and kernel weighting function for two test cases. The model particle spacing sets the initial distance between the moving...

  13. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

    Akkelin, S V; Karpenko, Iu A; Sinyukov, Yu M

    2008-01-01

    We develop a combined hydro-kinetic approach which incorporates hydrodynamical expansion of the systems formed in \\textit{A}+\\textit{A} collisions and their dynamical decoupling described by escape probabilities. The method corresponds to a generalized relaxation time ($\\tau_{\\text{rel}}$) approximation for Boltzmann equation applied to inhomogeneous expanding systems; at small $\\tau_{\\text{rel}}$ it also allows one to catch the viscous effects in hadronic component - hadron-resonance gas. We demonstrate how the approximation of sudden freeze-out can be obtained within this dynamical picture of continuous emission and find that hypersurfaces, corresponding to sharp freeze-out limit, are momentum dependent. The pion $m_{T}$ spectra are computed in the developed hydro-kinetic model, and compared with those obtained from ideal hydrodynamics with the Cooper-Frye isothermal prescription. Our results indicate that there does not exist a universal freeze-out temperature for pions with different momenta, and support ...

  14. Kaon differential flow in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Li, Ba; Zhang, B.; Sustich, AT; Ko, Che Ming.

    1999-01-01

    Gradient Synchrotron (AGS) at the Brookhaven National Laboratory (BNL). We find that in the absence of kaon potential the kaon differential flow is positive and increases with transverse momentum as that of nucleons. The repulsive kaon potential...

  15. Hydrodynamics and fluctuations in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    : centrality dependence Data > hydro Small discrepancy between STAR and PHENIX data Au-Au collision per nucleon is in the details! A small effect: Average value 0.3%, maximum value 3% Should we care? #12;A primer is independent of pT, as predicted by hydro. But... the value is significantly larger than 0.5 #12;More data

  16. Copper vs. Copper at the Relativistic Heavy Ion Collider (2005)

    SciTech Connect (OSTI)

    Brookhaven Lab - Fulvia Pilat

    2009-06-09

    To investigate a new form of matter not seen since the Big Bang, scientists are using a new experimental probe: collisions between two beams of copper ions. The use of intermediate size nuclei is expected to result in intermediate energy density - not as

  17. Triangularity and dipole asymmetry in relativistic heavy ion...

    Office of Scientific and Technical Information (OSTI)

    Institute of Physics Country of Publication: United States Language: English Subject: 73 NUCLEAR PHYSICS AND RADIATION PHYSICS; ASYMMETRY; BROOKHAVEN RHIC; COLLISIONS; CORRELATION...

  18. Copper vs. Copper at the Relativistic Heavy Ion Collider (2005)

    ScienceCinema (OSTI)

    Brookhaven Lab - Fulvia Pilat

    2010-01-08

    To investigate a new form of matter not seen since the Big Bang, scientists are using a new experimental probe: collisions between two beams of copper ions. The use of intermediate size nuclei is expected to result in intermediate energy density - not as

  19. Pion flow and antiflow in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Li, Bao-An; Ko, Che Ming.

    1996-01-01

    needs to be cautious in R24 53BAO-AN LI AND C. M. KO range of uy22.95u<0.35 are included. We note that the pro- jectile rapidity of 3.1 for the Au1Au reaction at pbeam /A510.8 GeV/c is in this rapidity bin. It is clear that the observation of R(pt... to provide new information about the collective flow that is complementary to that ob- tained from the analysis of the average transverse momen- tum in the reaction plane @8#. Figure 4 shows the ratio R(pt) as a function of pt for pions from the central...

  20. COMPLEX FRAGMENT EMISSION IN RELATIVISTIC HEAVY ION COLLISIONS

    E-Print Network [OSTI]

    Lemaire, M.-C.

    2010-01-01

    39;Amsden, Phys. Rev. gig (1978) I293. (28) C.Y. Wong,Gosset et al. , Phys. Rev. gig (1977) 629. L. Anderson, Ph.the high momentum region. For a giG%n fragment, the slope of

  1. Triangularity and dipole asymmetry in relativistic heavy ion...

    Office of Scientific and Technical Information (OSTI)

    Society Sponsoring Org: USDOE Country of Publication: United States Language: English Word Cloud More Like This Free Publicly Accessible Full Text Publisher's Accepted Manuscript...

  2. Elliptic flow of deuterons in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Oh, Yongseok; Ko, Che Ming.

    2007-01-01

    T ? p0T , which gives a similar result as Eq. (7) if we choose p0T = 0.75 GeV, a = 0.293, b = 0.460 GeV?1, c = ?0.175, ?? = 0.0332 GeV?1, and ? ? = 0.0579 GeV?3. B. Pion spectrum and elliptic flow For the pion pT spectrum, the parametrization used...

  3. Deuteron production and elliptic flow in relativistic heavy ion collisions 

    E-Print Network [OSTI]

    Oh, Yongseok; Lin, Zi-Wei; Ko, Che Ming.

    2009-01-01

    3p1d3p2 d6Np dx31dp31 d6Nn dx32dp32 ? fW (x?1, x?2; p?1, p?2)?(3)( pd ? p1 ? p2) (14) 064902-4 DEUTERON PRODUCTION AND ELLIPTIC FLOW IN . . . PHYSICAL REVIEW C 80, 064902 (2009) 0 5 10 15 20 t (fm/c) 0.02 0.03 0.04 0.05 0.06 0.07 N... [panel (b)]. It is seen that the nucleon number scaling of the proton and 064902-5 YONGSEOK OH, ZI-WEI LIN, AND CHE MING KO PHYSICAL REVIEW C 80, 064902 (2009) 0 0.5 1 1.5 pT /nN (GeV) 0 0.1 0.2 v 2 /n N p (expt) d (PHENIX) d (STAR) 0 0.2 0...

  4. Supersonic Jets in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Fuqiang Wang

    2006-10-23

    Mach-cone shock waves were proposed to explain the broad and perhaps double-peaked away-side 2-particle jet-correlations at RHIC; however, other mechanisms cannot be ruled out. Three-particle jet-correlation is needed in order to distinguish various physics mechanisms. In this talk the 3-particle jet-correlation measurements are presented and their implications are discussed.

  5. Triangularity and dipole asymmetry in relativistic heavy ion collisions

    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.Theory of rare Kaon and PionExperimentsConnect Conference:electronExamples

  6. Triangularity and dipole asymmetry in relativistic heavy ion collisions

    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.Theory of rare Kaon and PionExperimentsConnect

  7. Thermal, chemical and spectral equilibration in heavy-ion collisions

    E-Print Network [OSTI]

    Gábor András Almási; György Wolf

    2014-07-08

    We have considered the equilibration in a relativistic heavy ion collision using our transport model. We applied periodic boundary conditions to close the system in a box. We found that the thermal equilibration takes place in the first 20-40 fm/c which time is comparable to the duration of a heavy ion collision. The chemical equilibration is a much slower process and the system does not equilibrate in a heavy ion collision. We have also shown that the mass spectra of broad resonances immediately follows their in-medium spectral functions.

  8. A short introduction to heavy-ion physics

    E-Print Network [OSTI]

    Sourendu Gupta

    2015-08-23

    Heavy-ion collisions provide the only laboratory tests of relativistic quantum field theory at finite temperature. Understanding these is a necessary step in understanding the origins of our universe. These lectures introduce the subject to experimental particle physicists, in the hope that they will be useful to others as well. The phase diagram of QCD is briefly touched upon. Kinematic variables which arise in the collisions of heavy-ions beyond those in the collisions of protons or electrons are introduced. Finally, a few of the signals studied in heavy-ion collisions, and the kind of physics questions which they open up are discussed.

  9. High energy heavy ions: techniques and applications

    SciTech Connect (OSTI)

    Alonso, J.R.

    1985-04-01

    Pioneering work at the Bevalac has given significant insight into the field of relativistic heavy ions, both in the development of techniques for acceleration and delivery of these beams as well as in many novel areas of applications. This paper will outline our experiences at the Bevalac; ion sources, low velocity acceleration, matching to the synchrotron booster, and beam delivery. Applications discussed will include the observation of new effects in central nuclear collisions, production of beams of exotic short-lived (down to 1 ..mu..sec) isotopes through peripheral nuclear collisions, atomic physics with hydrogen-like uranium ions, effects of heavy ''cosmic rays'' on satellite equipment, and an ongoing cancer radiotherapy program with heavy ions. 39 refs., 6 figs., 1 tab.

  10. Relativistic mechanics in a general setting

    E-Print Network [OSTI]

    G. Sardanashvily

    2010-05-07

    Relativistic mechanics on an arbitrary manifold is formulated in the terms of jets of its one-dimensional submanifolds. A generic relativistic Lagrangian is constructed. Relativistic mechanics on a pseudo-Riemannian manifold is particularly considered.

  11. Heavy loads

    SciTech Connect (OSTI)

    Metz, D.

    1982-01-01

    The extreme pressures on the roof and walls of an earth-sheltered residential home are discussed and the need for careful planning is stressed. Pertinent terms are defined. Footings and wall structure (reinforced concrete walls and concrete block walls) are described. Roofing systems are discussed in detail and illustrated: (1) poured-in-place concrete roof slabs; (2) pre-cast concrete planks; and (3) heavy timber roofs. Insulation of earth-sheltered homes is reviewed in terms of using: (1) urethanes; (2) extruded polystyrene; and (3) expanded polystyrene. Advantages, disadvantages, R-factors, costs, and installation are discussed. (MJJ)

  12. Vibration by relativistic effects

    E-Print Network [OSTI]

    Enrique Oradaz Romay

    2005-12-27

    Relativity, time reversal invariance in mechanics and principle of causality can be in the bases of a type of vibration of the extensive objects. It is because, the detailed analysis of the relativistic movement of an extensive body entail that all the objects must have inherent a vibratory movement to their own size. Such effect does not happen when it works with point particles thus is not stranger who happens unnoticed in the traditional studies. Also we can find relation between the form of vibration of the extensive objects and the energy that calculates by quantum considerations.

  13. Measurements of phi meson production in relativistic heavy-ion collisions at the BNL Relativistic Heavy Ion Collider (RHIC)

    E-Print Network [OSTI]

    Sakuma, Tai

    We present results for the measurement of ? meson production via its charged kaon decay channel ??K[superscript +]K[superscript -] in Au+Au collisions at ?(s[subscript NN])=62.4,130, and 200 GeV, and in p+p and d+Au ...

  14. SUB-POPULATION BRAIN ATLASES

    E-Print Network [OSTI]

    Thompson, Paul

    SUB-POPULATION BRAIN ATLASES Paul Thompson PhD, Michael S. Mega MD PhD, and Arthur W. Toga PhD Laboratory of Neuro Imaging, Brain Mapping Division and Alzheimer's Disease Center Dept. of Neurology, UCLA School of Medicine, Los Angeles, CA 90095-1769 A Chapter in: Brain Mapping: The Methods (2nd Edition

  15. ATLAS Fast Tracker Simulation Challenges

    E-Print Network [OSTI]

    Adelman, Jahred; The ATLAS collaboration; Borodin, Mikhail; Chakraborty, Dhiman; García Navarro, José Enrique; Golubkov, Dmitry; Kama, Sami; Panitkin, Sergey; Smirnov, Yuri; Stewart, Graeme; Tompkins, Lauren; Vaniachine, Alexandre; Volpi, Guido

    2015-01-01

    To deal with Big Data flood from the ATLAS detector most events have to be rejected in the trigger system. the trigger rejection is complicated by the presence of a large number of minimum-bias events – the pileup. To limit pileup effects in the high luminosity environment of the LHC Run-2, ATLAS relies on full tracking provided by the Fast TracKer (FTK) implemented with custom electronics. The FTK data processing pipeline has to be simulated in preparation for LHC upgrades to support electronics design and develop trigger strategies at high luminosity. The simulation of the FTK - a highly parallelized system - has inherent performance bottlenecks on general-purpose CPUs. To take advantage of the Grid Computing power, the FTK simulation is integrated with Monte Carlo simulations at the Production System level above the ATLAS workload management system PanDA. We report on ATLAS experience with FTK simulations on the Grid and next steps for accommodating the growing requirements for resources during the LHC R...

  16. Galilean relativistic fluid mechanics

    E-Print Network [OSTI]

    Ván, Péter

    2015-01-01

    Single component Galilean-relativistic (nonrelativistic) fluids are treated independently of reference frames. The basic fields are given, their balances, thermodynamic relations and the entropy production is calculated. The usual relative basic fields, the mass, momentum and energy densities, the diffusion current density, the pressure tensor and the heat flux are the time- and spacelike components of the third order mass-momentum-energy density tensor according to a velocity field. The transformation rules of the basic fields are derived and prove that the non-equilibrium thermodynamic background theory, that is the Gibbs relation, extensivity condition and the entropy production is absolute, that is independent of the reference frame and also of the fluid velocity. --- Az egykomponensu Galilei-relativisztikus (azaz nemrelativisztikus) disszipativ folyadekokat vonatkoztatasi rendszertol fuggetlenul targyaljuk. Megadjuk az alapmennyisegeket, ezek merlegeit, a termodinamikai osszefuggeseket es kiszamoljuk az ...

  17. Polyanalytic relativistic second Bargmann transforms

    E-Print Network [OSTI]

    Zouhair Mouayn

    2015-04-01

    We construct coherent states through special superpositions of photon number states of the relativistic isotonic oscillator. In each superposition the coefficients are chosen to be L 2 eingenfunctions of a sigma weight Maass Laplacian on the Poincare disk, which are associated with discrete eigenvalues. For each nonzero m the associated coherent states transform constitutes the m true polyanalytic extension of a relativistic version of the second Bargmann transform, whose integral kernel is expressed in terms of a special Appel Kampe de Feriet hypergeometric function. The obtained results could be used to extend the known semi classical analysis of quantum dynamics of the relativistic isotonic oscillator.

  18. Evolution of the ATLAS Nightly Build System

    E-Print Network [OSTI]

    Undrus, A

    2012-01-01

    The ATLAS Nightly Build System is a major component in the ATLAS collaborative software organization, validation, and code approval scheme. For over 10 years of development it has evolved into a factory for automatic release production and grid distribution. The 50 multi-platform branches of ATLAS releases provide vast opportunities for testing new packages, verification of patches to existing software, and migration to new platforms and compilers for ATLAS code that currently contains 2200 packages with 4 million C++ and 1.4 million python scripting lines written by about 1000 developers. Recent development was focused on the integration of ATLAS Nightly Builds and Installation systems. The nightly releases are distributed and validated and some are transformed into stable releases used for data processing worldwide. The ATLAS Nightly System is managed by the NICOS control tool on a computing farm with 50 powerful multiprocessor nodes. NICOS provides the fully automated framework for the release builds, test...

  19. ATLAS Inner Detector Event Data Model

    SciTech Connect (OSTI)

    ATLAS; Akesson, F.; Costa, M.J.; Dobos, D.; Elsing, M.; Fleischmann, S.; Gaponenko, A.; Gnanvo, K.; Keener, P.T.; Liebig, W.; Moyse, E.; Salzburger, A.; Siebel, M.; Wildauer, A.

    2007-12-12

    The data model for event reconstruction (EDM) in the Inner Detector of the ATLAS experiment is presented. Different data classes represent evolving stages in the reconstruction data flow, and specific derived classes exist for the sub-detectors. The Inner Detector EDM also extends the data model for common tracking in ATLAS and is integrated into the modular design of the ATLAS high-level trigger and off-line software.

  20. Search for high-mass states with one lepton plus missing transverse momentum in proton–proton collisions at ?s = 7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    The ATLAS detector is used to search for high-mass states, such as heavy charged gauge bosons (W?,W*), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of pp ...

  1. Search for new phenomena in the WW??????? final state in pp collisions at ?s = 7 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    This Letter reports a search for a heavy particle that decays to WW using events produced in pp collisions at ?s = 7 TeV. The data were recorded in 2011 by the ATLAS detector and correspond to an integrated luminosity of ...

  2. Search for a CP-odd Higgs boson decaying to Zh in pp collisions at ?s = 8 TeV with the ATLAS detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search for a heavy, CP-odd Higgs boson, A, decaying into a Z boson and a 125 GeV Higgs boson, h, with the ATLAS detector at the LHC is presented. The search uses proton–proton collision data at a centre-of-mass energy ...

  3. Delbouille, L., Roland, G., Brault, J., and Testerman, L., 1981, Photometric Atlas of the Solar Spectrum from 1850 to 10000 cm 01

    E-Print Network [OSTI]

    Kurucz, Robert L.

    REFERENCES Delbouille, L., Roland, G., Brault, J., and Testerman, L., 1981, Photometric Atlas Space, NASA Reference Pub. 1224, in two vol., 1216 pp. Kohl, J.L., Parkinson, W.H., and Kurucz, R. The heavy lines are the observed FTS spectrum from James Brault at Kitt Peak. The resolution is 522000

  4. Heavy metal biosensor

    DOE Patents [OSTI]

    Hillson, Nathan J; Shapiro, Lucille; Hu, Ping; Andersen, Gary L

    2014-04-15

    Compositions and methods are provided for detection of certain heavy metals using bacterial whole cell biosensors.

  5. Yield and suppression of electrons from open heavy-flavor decays in heavy-ion collisions

    E-Print Network [OSTI]

    Anders Knospe

    2011-12-31

    Measurements by the STAR and PHENIX collaborations indicate that a quark-gluon plasma, a hot and dense state of matter in which quarks and gluons are not confined inside hadrons, is formed in heavy-ion collisions at the Relativistic Heavy Ion Collider. Charm and bottom quarks have been predicted to interact with the medium differently than the light quarks; a study of heavy quark interactions with the medium provides an important test of theoretical models of the quark-gluon plasma. The spectrum of non-photonic electrons (and positrons) is dominated by electrons from the semileptonic decays of D and B mesons. Therefore, non-photonic electrons serve as proxies for heavy quarks. A measurement of the modification of the non-photonic electron spectrum in nucleus-nucleus collisions relative to p + p collisions allows the interactions of heavy quarks with the medium to be studied. Previous measurements indicate that high-transverse-momentum non-photonic electrons are suppressed in Au + Au collisions at 200 GeV (center-of-mass energy per nucleon pair) relative to p + p collisions at the same energy. The magnitude of that suppression is larger than was anticipated and it has been a challenge for theoretical models to predict the in-medium energy loss of light and heavy quarks simultaneously. This dissertation presents the first measurement of the yield of non-photonic electrons from open heavy-flavor decays in Cu + Cu collisions at 200 GeV and the suppression of that yield relative to p + p collisions. A comparison of this result to similar results for Au + Au collisions provides some indication that the geometry of a heavy-ion collision affects the average amount of energy loss by heavy quarks passing through the quark-gluon plasma.

  6. Alignment strategy for the ATLAS tracker

    SciTech Connect (OSTI)

    ATLAS; Golling, T.

    2007-09-23

    The ATLAS experiment is a multi-purpose particle detector that will study high-energy particle collisions produced by the Large Hadron Collider. For the reconstruction of charged particles, and their production and their decay vertices, ATLAS is equipped with a sophisticated tracking system, unprecedented in size and complexity. Full exploitation of both the Inner Detector and the muon spectrometer requires an accurate alignment. The challenge of aligning the ATLAS tracking devices is discussed, and the ATLAS alignment strategy is presented and illustrated with both data and Monte Carlo results.

  7. Stress Tensor and Bulk Viscosity in Relativistic Nuclear Collisions

    E-Print Network [OSTI]

    Rainer J. Fries; Berndt Müller; Andreas Schäfer

    2008-08-30

    We discuss the influence of different initial conditions for the stress tensor and the effect of bulk viscosity on the expansion and cooling of the fireball created in relativistic heavy-ion collisions. In particular, we explore the evolution of longitudinal and transverse components of the pressure and the extent of dissipative entropy production in the one-dimensional, boost-invariant hydrodynamic model. We find that a bulk viscosity consistent with recent estimates from lattice QCD further slows the equilibration of the system, however it does not significantly increase the entropy produced.

  8. Search for Pair Production of Heavy Top-Like Quarks Decaying to a High-p[subscript T]W Boson and a b Quark in the Lepton Plus Jets Final State at ?s = 7 TeV with the ATLAS Detector

    E-Print Network [OSTI]

    Taylor, Frank E.

    A search is presented for production of a heavy up-type quark (t[superscript ?]) together with its antiparticle, assuming a significant branching ratio for subsequent decay into a W boson and a b quark. The search is ...

  9. Real-Time Flavor Tagging Algorithms in ATLAS

    E-Print Network [OSTI]

    Hetherly, Jeffrey Wayne; The ATLAS collaboration; Zivkovic, Lidija

    2015-01-01

    In high-energy physics experiments, online selection is crucial to select interesting collisions from the large data volume. ATLAS b-jet triggers are designed to identify heavy-flavour content in real-time and provide the only option to efficiently record events with fully hadronic final states containing b-jets. In doing so, two different, but related, challenges are faced. The physics goal is to optimise as far as possible the rejection of light jets, while retaining a high efficiency on selecting b-jets and maintaining affordable trigger rates without raising jet energy thresholds. This results in a challenging computing task, as tracks and their corresponding vertices must be reconstructed and analysed for each jet above the desired threshold, regardless of the increasingly adverse pile-up conditions. We present an overview of the ATLAS strategy for online b-jet selection for the LHC Run 2, including the use of novel methods and sophisticated algorithms designed to face the above mentioned challenges. A f...

  10. Practical relativistic bit commitment

    E-Print Network [OSTI]

    Tommaso Lunghi; J?drzej Kaniewski; Felix Bussieres; Raphael Houlmann; Marco Tomamichel; Stephanie Wehner; Hugo Zbinden

    2015-06-25

    Bit commitment is a fundamental cryptographic primitive in which Alice wishes to commit a secret bit to Bob. Perfectly secure bit commitment between two mistrustful parties is impossible through asynchronous exchange of quantum information. Perfect security is however possible when Alice and Bob each split into several agents exchanging classical information at times and locations suitably chosen to satisfy specific relativistic constraints. In this Letter we first revisit a previously proposed scheme that realizes bit commitment using only classical communication. We prove that the protocol is secure against quantum adversaries for a duration limited by the light-speed communication time between the locations of the agents. We then propose a novel multi-round scheme based on finite-field arithmetic that extends the commitment time beyond this limit, and we prove its security against classical attacks. Finally, we present an implementation of these protocols using dedicated hardware and we show how it could be used to realize commitments of duration ranging up to 212 milliseconds by agents occupying antipodal locations on the Earth.

  11. Design of a relativistic Klystron Two-Beam Accelerator Prototype

    E-Print Network [OSTI]

    Westenskow, G.

    2008-01-01

    Design of a Relativistic Klystron Two-Beam Accelerator147 DESIGN OF A RELATIVISTIC KLYSTRON TWO-BEAM ACCELERATORin an Extended Relativistic Klystron," this conference.

  12. New physics searches with B mesons at the ATLAS experiment

    E-Print Network [OSTI]

    Nooney, Tamsin; The ATLAS collaboration

    2015-01-01

    The large amount of Heavy Flavour data collected by the ATLAS experiment is potentially sensitive to New Physics, which may be found in the mixing of B meson states, or through processes that are naturally suppressed in the Standard Model. We present the most recent results on the measurement of the decay of the $B_{s}$ into $J/\\psi$ $\\phi$ based on full data collected in LHC Run-1 and with updated flavour tagging improving the accuracy in the CP-violating phase $\\phi_{s}$. We also present the measurement of the decay time difference in the $B_{d}$ system. The most recent results on the search for the rare decay $B_{s}$ ($B^{0}$) $\\rightarrow$ $\\mu^{+}$ $\\mu^{-}$ are presented as well as results on the angular distribution parameters $A_{FB}$ and $F_{L}$ describing the decay $B_{d}$ $\\rightarrow$ $K^{*}\\mu^{+}\\mu^{-}$ $\\rightarrow$ $K^{+}\\pi^{-} \\mu^{+} \\mu^{-}$.

  13. 2TeV Higgs boson and ATLAS diboson excess

    E-Print Network [OSTI]

    Chen, Chuan-Hung

    2015-01-01

    Diboson resonance with mass around 2 TeV in the dijet invariant mass spectrum is reported by ATLAS experiment in proton-proton collisions at $\\sqrt{s}=8$ TeV. We propose that the candidate of resonance is a heavy neutral Higgs $H^0$ or charged Higgs $H^\\pm$ and use the extended two-Higgs-doublet (THD) to demonstrate the potentiality. We find that the large Yukawa coupling to the first generation of quarks can be realized in THD and the required value for producing the right resonance production cross section is of ${\\cal O}(0.06-0.2)$. Besides $WW/ZZ$ channels, we find that if the mass of pseudoscalar $A^0$ satisfies the jet mass tagging condition $|m_j - m_{Z/W}|< 13$ GeV, the diboson excess could be also caused by $ZA^0$ or $WA^0$ channel.

  14. Measurement of Single-top Quark Production with ATLAS Data

    E-Print Network [OSTI]

    J. L. Holzbauer; for the ATLAS Collaboration

    2011-11-14

    Single-top production processes have been studied using 0.7 fb-1 of data from 7 TeV center-of-mass energy proton-proton collisions collected with the ATLAS detector at the LHC. Single-top is electroweak top production and the standard model includes three production modes. Each contains a Wtb vertex, allowing the possibility of a direct measurement of the CKM matrix element |Vtb|. Single-top could also be sensitive to new physics, such as flavor changing neutral currents or heavy W' bosons. Using cut-based selections, a limit of production and production. For the t-channel measurement, both cut-based and neural network analyses are performed and the cross-section is measured to be 90 +32 -22 pb, where 65 +28 -19 pb is expected according to standard model.

  15. The ATLAS Silicon Pixel Sensors

    E-Print Network [OSTI]

    Alam, M S; Einsweiler, K F; Emes, J; Gilchriese, M G D; Joshi, A; Kleinfelder, S A; Marchesini, R; McCormack, F; Milgrome, O; Palaio, N; Pengg, F; Richardson, J; Zizka, G; Ackers, M; Andreazza, A; Comes, G; Fischer, P; Keil, M; Klasen, V; Kühl, T; Meuser, S; Ockenfels, W; Raith, B; Treis, J; Wermes, N; Gössling, C; Hügging, F G; Wüstenfeld, J; Wunstorf, R; Barberis, D; Beccherle, R; Darbo, G; Gagliardi, G; Gemme, C; Morettini, P; Musico, P; Osculati, B; Parodi, F; Rossi, L; Blanquart, L; Breugnon, P; Calvet, D; Clemens, J-C; Delpierre, P A; Hallewell, G D; Laugier, D; Mouthuy, T; Rozanov, A; Valin, I; Aleppo, M; Caccia, M; Ragusa, F; Troncon, C; Lutz, Gerhard; Richter, R H; Rohe, T; Brandl, A; Gorfine, G; Hoeferkamp, M; Seidel, SC; Boyd, GR; Skubic, P L; Sícho, P; Tomasek, L; Vrba, V; Holder, M; Ziolkowski, M; D'Auria, S; del Papa, C; Charles, E; Fasching, D; Becks, K H; Lenzen, G; Linder, C

    2001-01-01

    Prototype sensors for the ATLAS silicon pixel detector have been developed. The design of the sensors is guided by the need to operate them in the severe LHC radiation environment at up to several hundred volts while maintaining a good signal-to-noise ratio, small cell size, and minimal multiple scattering. The ability to be operated under full bias for electrical characterization prior to the attachment of the readout integrated circuit electronics is also desired.

  16. ATLAS results on top properties

    E-Print Network [OSTI]

    F. Derue

    2014-08-26

    Recent measurements of top quark properties using $t{\\bar t}$ events produced in proton-proton collisions at the Large Hadron Collider with centre of mass energies of 7 and 8 TeV and detected by the ATLAS experiment are presented. These results include top quark mass, the top and anti-top mass difference, the electric charge, the top quark polarization and spin correlation, the $t{\\bar t}$ charge asymmetry and the search for flavour changing neutral currents.

  17. Study of electromagnetic dissociation of heavy nuclei at the relativistic heavy ion collider 

    E-Print Network [OSTI]

    Makeev, Andrei

    2001-01-01

    the interaction vertex, making collision centrality measurements, forming triggers, rejecting background and are also used for a number of physics measurements. The experimental data from the BRAHMS zero-degree calorimeters, beam-beam counters and tile...

  18. Relativistic theory of nuclear spin-rotation tensor with kinetically balanced rotational London orbitals

    SciTech Connect (OSTI)

    Xiao, Yunlong; Zhang, Yong; Liu, Wenjian

    2014-10-28

    Both kinetically balanced (KB) and kinetically unbalanced (KU) rotational London orbitals (RLO) are proposed to resolve the slow basis set convergence in relativistic calculations of nuclear spin-rotation (NSR) coupling tensors of molecules containing heavy elements [Y. Xiao and W. Liu, J. Chem. Phys. 138, 134104 (2013)]. While they perform rather similarly, the KB-RLO Ansatz is clearly preferred as it ensures the correct nonrelativistic limit even with a finite basis. Moreover, it gives rise to the same “direct relativistic mapping” between nuclear magnetic resonance shielding and NSR coupling tensors as that without using the London orbitals [Y. Xiao, Y. Zhang, and W. Liu, J. Chem. Theory Comput. 10, 600 (2014)].

  19. In Situ Jet Energy Calibration In Atlas Based On

    E-Print Network [OSTI]

    Hupkes, Hermen Jan

    In Situ Jet Energy Calibration In Atlas Based On Z+Jet Events By Hermen Jan Hupkes 252 Ge; IN SITU JET ENERGY CALIBRATION IN ATLAS BASED ON Z+JET EVENTS Hermen Jan Hupkes Mathematisch Instituut #12; #12; Contents 1 Introduction 1 2 The Atlas Detector 7 3 Jet Measurements in Atlas 11 3

  20. In Situ Jet Energy Calibration In Atlas Based On

    E-Print Network [OSTI]

    Hupkes, Hermen Jan

    In Situ Jet Energy Calibration In Atlas Based On Z+Jet Events By Hermen Jan Hupkes 252 Ge SITU JET ENERGY CALIBRATION IN ATLAS BASED ON Z+JET EVENTS Hermen Jan Hupkes Mathematisch Instituut #12;#12;Contents 1 Introduction 1 2 The Atlas Detector 7 3 Jet Measurements in Atlas 11 3

  1. Refining a relativistic, hydrodynamic solver: Admitting ultra-relativistic flows

    E-Print Network [OSTI]

    J. P. Bernstein; P. A. Hughes

    2009-07-23

    We have undertaken the simulation of hydrodynamic flows with bulk Lorentz factors in the range 10^2--10^6. We discuss the application of an existing relativistic, hydrodynamic primitive-variable recovery algorithm to a study of pulsar winds, and, in particular, the refinement made to admit such ultra-relativistic flows. We show that an iterative quartic root finder breaks down for Lorentz factors above 10^2 and employ an analytic root finder as a solution. We find that the former, which is known to be robust for Lorentz factors up to at least 50, offers a 24% speed advantage. We demonstrate the existence of a simple diagnostic allowing for a hybrid primitives recovery algorithm that includes an automatic, real-time toggle between the iterative and analytical methods. We further determine the accuracy of the iterative and hybrid algorithms for a comprehensive selection of input parameters and demonstrate the latter's capability to elucidate the internal structure of ultra-relativistic plasmas. In particular, we discuss simulations showing that the interaction of a light, ultra-relativistic pulsar wind with a slow, dense ambient medium can give rise to asymmetry reminiscent of the Guitar nebula leading to the formation of a relativistic backflow harboring a series of internal shockwaves. The shockwaves provide thermalized energy that is available for the continued inflation of the PWN bubble. In turn, the bubble enhances the asymmetry, thereby providing positive feedback to the backflow.

  2. Measurements of charged particle spectra and nuclear modification factor in p+Pb collisions with the ATLAS detector

    E-Print Network [OSTI]

    ,

    2015-01-01

    The ATLAS detector at the LHC obtained the sample of p+Pb data at $\\sqrt{s_{NN}}={}$5.02TeV with integrated luminosity of 25nb${}^{-1}$, which can be compared to the pp data obtained by interpolating pp measurements at $\\sqrt{s}={}$2.76TeV and 7TeV. Due to the excellent capabilities of the ATLAS detector, and its stable operation in heavy ion as well as proton-proton physics runs, the data allow measurements of the nuclear modification factor, ratio of heavy ion charged particle spectra divided by pp reference, in different centrality classes over a wide range of rapidity. The charged particle nuclear modification factor is found to vary significantly as a function of transverse momentum with a stronger dependence in more peripheral collisions.

  3. Measurements of charged particle spectra and nuclear modification factor in p+Pb collisions with the ATLAS detector

    E-Print Network [OSTI]

    Petr Balek

    2015-09-03

    The ATLAS detector at the LHC obtained the sample of p+Pb data at $\\sqrt{s_{NN}}={}$5.02TeV with integrated luminosity of 25nb${}^{-1}$, which can be compared to the pp data obtained by interpolating pp measurements at $\\sqrt{s}={}$2.76TeV and 7TeV. Due to the excellent capabilities of the ATLAS detector, and its stable operation in heavy ion as well as proton-proton physics runs, the data allow measurements of the nuclear modification factor, ratio of heavy ion charged particle spectra divided by pp reference, in different centrality classes over a wide range of rapidity. The charged particle nuclear modification factor is found to vary significantly as a function of transverse momentum with a stronger dependence in more peripheral collisions.

  4. Pixel Sensors for ATLAS Sally Seidel

    E-Print Network [OSTI]

    Seidel, Sally

    Albuquerque, New Mexico 87131, USA for the ATLAS Collaboration 8 May 1998 Abstract The design and fabrication the desire to provide bias to every pixel without attaching the readout integrated circuit. This is expectedPixel Sensors for ATLAS Sally Seidel Department of Physics and Astronomy University of New Mexico

  5. Philippines Wind Energy Resource Atlas Development

    SciTech Connect (OSTI)

    Elliott, D.

    2000-11-29

    This paper describes the creation of a comprehensive wind energy resource atlas for the Philippines. The atlas was created to facilitate the rapid identification of good wind resource areas and understanding of the salient wind characteristics. Detailed wind resource maps were generated for the entire country using an advanced wind mapping technique and innovative assessment methods recently developed at the National Renewable Energy Laboratory.

  6. Renewable Energy Atlas of the United States

    SciTech Connect (OSTI)

    Kuiper, J.; Hlava, K.; Greenwood, H.; Carr, A.

    2013-12-13

    The Renewable Energy Atlas (Atlas) of the United States is a compilation of geospatial data focused on renewable energy resources, federal land ownership, and base map reference information. This report explains how to add the Atlas to your computer and install the associated software. The report also includes: ? A description of each of the components of the Atlas; ? Lists of the Geographic Information System (GIS) database content and sources; and ? A brief introduction to the major renewable energy technologies. The Atlas includes the following: ? A GIS database organized as a set of Environmental Systems Research Institute (ESRI) ArcGIS Personal GeoDatabases, and ? ESRI ArcReader and ArcGIS project files providing an interactive map visualization and analysis interface.

  7. The Next Generation ATLAS Production System

    E-Print Network [OSTI]

    Borodin, Mikhail; The ATLAS collaboration; Golubkov, Dmitry; Klimentov, Alexei; Maeno, Tadashi; Mashinistov, Ruslan; Vaniachine, Alexandre

    2015-01-01

    The ATLAS experiment at LHC data processing and simulation grows continuously, as more data and more use cases emerge. For data processing the ATLAS experiment adopted the data transformation approach, where software applications transform the input data into outputs. In the ATLAS production system, each data transformation is represented by a task, a collection of many jobs, dynamically submitted by the ATLAS workload management system (PanDA/JEDI) and executed on the Grid, clouds and supercomputers. Patterns in ATLAS data transformation workflows composed of many tasks provided a scalable production system framework for template definitions of the many-tasks workflows. User interface and system logic of these workflows are being implemented in the Database Engine for Tasks (DEFT). Such development required using modern computing technologies and approaches. We report technical details of this development: database implementation, server logic and Web user interface technologies.

  8. Search for Higgs boson like high mass resonances in the bosonic decay channels with ATLAS and CMS

    E-Print Network [OSTI]

    Lo Sterzo, Francesco; The ATLAS collaboration

    2015-01-01

    Searches for an additional heavy Higgs-like boson have been performed by both ATLAS and CMS with data collected in the Run 1 of the LHC. This document reports searches in the diboson decay channels ($\\gamma\\gamma$, $WW$, $ZZ$). Exclusion limits have been set for different hypotheses: model independent narrow-resonance, Standard Model-like Higgs, Electroweak Singlet and 2HDM. No excesses are found over the Standard Model background-only expectation.

  9. Thermalization of heavy quarks in the quark-gluon plasma 

    E-Print Network [OSTI]

    van Hees, H.; Rapp, Ralf.

    2005-01-01

    the BNL Relativistic Heavy-Ion Collider (RHIC) indicate the possibility that the D-meson v2 could be similar in magnitude to the one of light hadrons [10,11]. Since the c quark is rather heavy, this would be quite remarkable and could provide important... temperature) has been suggested as a mechanism to enhance partonic cross sections [12?14] to facilitate rapid thermalization of the bulk matter at RHIC as required in hy- drodynamical models. The notion of charmonium resonances in the QGP [15,16] has been...

  10. Carbon Storage Atlas - Fifth Edition (Atlas V) (2015)

    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 OutreachProductswsicloudwsiclouddenDVA N C E D B LReports from thecarbon captureCarbon Storage Atlas - Fifth

  11. Adapting High Brightness Relativistic Electron Beams for Ultrafast Science

    E-Print Network [OSTI]

    Scoby, Cheyne Matthew

    2012-01-01

    111 Transverse electron beamfemtosecond relativistic electron beams . . Organization offields of a relativistic electron beam. Phys. Rev. Lett. ,

  12. Holographic view of non-relativistic physics

    E-Print Network [OSTI]

    Balasubramanian, Koushik

    2012-01-01

    Motivated by the AdS/CFT correspondence for relativistic CFTs, it seems natural to generalize it to non-relativistic CFTs. Such a dual description could provide insight into strong coupling phenomena observed in condensed ...

  13. Relativistic Positioning Systems: current status

    E-Print Network [OSTI]

    Bartolomé Coll; Joan J. Ferrando; Juan A. Morales-Lladosa

    2009-06-03

    A {\\em relativistic positioning system} consists in a set of four clocks broadcasting their respective proper time by means of light signals. Among them, the more important ones are the {\\em auto-located positioning systems,} in which every clock broadcasts not only its proper time but also the proper times that it receives from the other three. At this level, no reference to any exterior system (the Earth surface, for example) and no synchronization are needed. The current status of the theory of relativistic positioning systems is sketched.

  14. Relativistic mass and modern physics

    E-Print Network [OSTI]

    Z. K. Silagadze

    2014-12-15

    At first sight, arguments for and against the notion of relativistic mass look like a notorious intra-Lilliputian quarrel between Big-Endians (those who broke their eggs at the larger end) and Little-Endians. However, upon closer inspection we discover that the relativistic mass notion is alien to the spirit of modern physics to a much greater extent than it seems. To demonstrate an abyss between the modern approach and archaic notions, in this paper we explore how the concept of mass is introduced in modern physics. This modern approach reveals a deep cohomological origin of mass.

  15. Phenomenological Relativistic Energy Density Functionals

    SciTech Connect (OSTI)

    Lalazissis, G. A.; Kartzikos, S.; Niksic, T.; Paar, N.; Vretenar, D.; Ring, P.

    2009-08-26

    The framework of relativistic nuclear energy density functionals is applied to the description of a variety of nuclear structure phenomena, not only in spherical and deformed nuclei along the valley of beta-stability, but also in exotic systems with extreme isospin values and close to the particle drip-lines. Dynamical aspects of exotic nuclear structure is explored using the fully consistent quasiparticle random-phase approximation based on the relativistic Hartree-Bogoliubov model. Recent applications of energy density functionals with explicit density dependence of the meson-nucleon couplings are presented.

  16. Characteristic hypersurfaces in a relativistic superfluid theory

    E-Print Network [OSTI]

    B. Linet

    1998-12-16

    By discussing the Cauchy problem, we determine the covariant equation of the characteristic hypersurfaces in a relativistic superfluid theory.

  17. An implicit numerical algorithm general relativistic hydrodynamics

    E-Print Network [OSTI]

    A. Hujeirat

    2008-01-09

    An implicit numerical algorithm general relativistic hydrodynamics This article has been replaced by arXiv:0801.1017

  18. Early Top Physics with ATLAS

    E-Print Network [OSTI]

    J. Schieck

    2009-01-12

    The ATLAS detector is one of the two multi-purpose experiments located at the Large Hadron Collider (LHC) at CERN and is expected to collect first collision data in summer 2009. Due to the large top-quark production cross-section the LHC will function as a top-quark factory allowing to measure top-quark properties even at initial luminosities. We present some recently-performed studies, focussing on measurements of the top pair and single top production cross-sections with the first fb-1 of data. The potential for the measurement of other top-quark properties like the mass will be also briefly discussed.

  19. ATLAS 25th Anniversary Celebration

    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 Room News Publications Traditional Knowledge Kiosks Barrow,ARM: ThreeATHENA could reduce ATLAS th

  20. ATLAS Science and Technology Review

    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 Room News Publications Traditional Knowledge Kiosks Barrow,ARM: ThreeATHENA could reduce ATLAS thth

  1. MHK Atlas | Open Energy Information

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX ECoop Inc Jump to: navigation, search Name: Lyon-Lincoln Electric CoopMAPSAMHK Atlas

  2. $?/s$ 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.

  3. Relativistic Blastwaves and Synchrotron Emission

    E-Print Network [OSTI]

    T. P. Downes; P. Duffy; S. Komissarov

    2002-01-22

    Relativistic shocks accelerate particles by the first order Fermi mechanism. These particles then emit synchrotron emission in the post shock gas. We have developed a numerical code which integrates the relativistic Euler equations for fluid dynamics with a general equation of state, together with the Liouville equation for the accelerated particles. We present tests of this code and, in addition, we use it to study the gamma ray burst afterglow predicted by the fireball model, along with the hydrodynamics of a relativistic blastwave. We find that, while, broadly speaking, the behaviour of the emission is similar to that already predicted with semi-analytic approaches, the detailed behaviour is somewhat different. The ``breaks'' in the synchrotron spectrum behave differently with time, and the spectrum above the final break is harder than previously expected. These effects are due to the incorporation of the geometry of the (spherical) blastwave, along with relativistic beaming and adiabatic cooling of the energetic particles leading to a mix, in the observed spectrum, between recently injected "uncooled" particles and the older "cooled" population in different parts of the evolving, inhomogeneous flow.

  4. Kinetic equilibrium and relativistic thermodynamics

    E-Print Network [OSTI]

    P. Ván

    2011-02-01

    Relativistic thermodynamics is treated from the point of view of kinetic theory. It is shown that the generalized J\\"uttner distribution suggested in [1] is compatible with kinetic equilibrium. The requirement of compatibility of kinetic and thermodynamic equilibrium reveals several generalizations of the Gibbs relation where the velocity field is an independent thermodynamic variable.

  5. RELATIVISTIC GEOMETRY AND QUANTUM ELECTRODYNAMICS

    E-Print Network [OSTI]

    González Martín, Gustavo R.

    the fundamental aspects of quantum theory. SB/F/272-99 #12;2 Introduction A geometrical unified theory:\\\\prof.usb.ve\\ggonzalm\\ Excitations of a relativistic geometry were used to represent the theory of quantum electrodynamics. The connection excitations and the frame excitations reduce, respectively, to the electromagnetic field operator

  6. Systematic studies of the centrality and root S(NN) dependence of the dE(T)/d eta and dN(ch)/d eta in heavy ion collisions at midrapidity 

    E-Print Network [OSTI]

    Adler, SS; Afanasiev, S.; Aidala, C.; Ajitanand, NN; Akiba, Y.; Alexander, J.; Amirikas, R.; Aphecetche, L.; Aronson, SH; Averbeck, R.; Awes, TC; Azmoun, R.; Babintsev, V.; Baldisseri, A.; Barish, KN; Barnes, PD; Bassalleck, B.; Bathe, S.; Batsouli, S.; Baublis, V.; Bazilevsky, A.; Belikov, S.; Berdnikov, Y.; Bhagavatula, S.; Boissevain, JG; Borel, H.; Borenstein, S.; Brooks, ML; Brown, DS; Bruner, N.; Bucher, D.; Buesching, H.; Bumazhnov, V.; Bunce, G.; Burward-Hoy, JM; Butsyk, S.; Camard, X.; Chai, JS; Chand, P.; Chang, WC; Chernichenko, S.; Chi, CY; Chiba, J.; Chiu, M.; Choi, IJ; Choi, J.; Choudhury, R. K.; Chujo, T.; Cianciolo, V.; Cobigo, Y.; Cole, BA; Constantin, P.; d'Enterria, DG; David, G.; Delagrange, H.; Denisov, A.; Deshpande, A.; Desmond, EJ; Dietzsch, O.; Drapier, O.; Drees, A.; du Rietz, R.; Durum, A.; Dutta, D.; Efremenko, YV; El Chenawi, K.; Enokizono, A.; En'yo, H.; Esumi, S.; Ewell, L.; Fields, DE; Fleuret, F.; Fokin, SL; Fox, BD; Fraenkel, Z.; Frantz, JE; Franz, A.; Frawley, AD; Fung, SY; Garpman, S.; Ghosh, TK; Glenn, A.; Gogiberidze, G.; Gonin, M.; Gosset, J.; Goto, Y.; de Cassagnac, RG; Grau, N.; Greene, SV; Perdekamp, MG; Guryn, W.; Gustafsson, HA; Hachiya, T.; Haggerty, JS; Hamagaki, H.; Hansen, AG; Hartouni, EP; Harvey, M.; Hayano, R.; He, X.; Heffner, M.; Hemmick, TK; Heuser, JM; Hibino, M.; Hill, JC; Holzmann, W.; Homma, K.; Hong, B.; Hoover, A.; Ichihara, T.; Ikonnikov, VV; Imai, K.; Isenhower, D.; Ishihara, M.; Issah, M.; Isupov, A.; Jacak, BV; Jang, WY; Jeong, Y.; Jia, J.; Jinnouchi, O.; Johnson, BM; Johnson, SC; Joo, KS; Jouan, D.; Kametani, S.; Kamihara, N.; Kang, JH; Kapoor, SS; Katou, K.; Kelly, S.; Khachaturov, B.; Khanzadeev, A.; Kikuchi, J.; Kim, DH; Kim, DJ; Kim, DW; Kim, E.; Kim, GB; Kim, HJ; Kistenev, E.; Kiyomichi, A.; Kiyoyama, K.; Klein-Boesing, C.; Kobayashi, H.; Kochenda, L.; Kochetkov, V.; Koehler, D.; Kohama, T.; Kopytine, M.; Kotchetkov, D.; Kozlov, A.; Kroon, PJ; Kuberg, CH; Kurita, K.; Kuroki, Y.; Kweon, MJ; Kwon, Y.; Kyle, GS; Lacey, R.; Ladygin, V.; Lajoie, JG; Lebedev, A.; Leckey, S.; Lee, DM; Lee, S.; Leitch, MJ; Li, XH; Lim, H.; Litvinenko, A.; Liu, MX; Liu, Y.; Maguire, CF; Makdisi, YI; Malakhov, A.; Manko, VI; Mao, Y.; Martinez, G.; Marx, MD; Masui, H.; Matathias, F.; Matsumoto, T.; McGaughey, PL; Melnikov, E.; Mendenhall, M.; Messer, F.; Miake, Y.; Milan, J.; Miller, TE; Milov, A.; Mioduszewski, Saskia; Mischke, RE; Mishra, GC; Mitchell, JT; Mohanty, AK; Morrison, DP; Moss, JM; Muhlbacher, F.; Mukhopadhyay, D.; Muniruzzaman, M.; Murata, J.; Nagamiya, S.; Nagle, JL; Nakamura, T.; Nandi, BK; Nara, M.; Newby, J.; Nilsson, P.; Nyanin, AS; Nystrand, J.; O'Brien, E.; Ogilvie, CA; Ohnishi, H.; Ojha, ID; Okada, K.; Ono, M.; Onuchin, V.; Oskarsson, A.; Otterlund, I.; Oyama, K.; Ozawa, K.; Pal, D.; Palounek, APT; Pantuev, VS; Papavassiliou, V.; Park, J.; Parmar, A.; Pate, SF; Peitzmann, T.; Peng, JC; Peresedov, V.; Pinkenburg, C.; Pisani, RP; Plasil, F.; Purschke, ML; Purwar, AK; Rak, J.; Ravinovich, I.; Read, KF; Reuter, M.; Reygers, K.; Riabov, V.; Riabov, Y.; Roche, G.; Romana, A.; Rosati, M.; Rosnet, P.; Ryu, SS; Sadler, ME; Saito, N.; Sakaguchi, T.; Sakai, M.; Sakai, S.; Samsonov, V.; Sanfratello, L.; Santo, R.; Sato, HD; Sato, S.; Sawada, S.; Schutz, Y.; Semenov, V.; Seto, R.; Shaw, MR; Shea, TK; Shibata, TA; Shigaki, K.; Shiina, T.; Silva, CL; Silvermyr, D.; Sim, KS; Singh, CP; Singh, V.; Sivertz, M.; Soldatov, A.; Soltz, RA; Sondheim, WE; Sorensen, SP; Sourikova, IV; Staley, F.; Stankus, PW; Stenlund, E.; Stepanov, M.; Ster, A.; Stoll, SP; Sugitate, T.; Sullivan, J. P.; Takagui, EM; Taketani, A.; Tamai, M.; Tanaka, KH; Tanaka, Y.; Tanida, K.; Tannenbaum, MJ; Tarjan, P.; Tepe, JD; Thomas, TL; Tojo, J.; Torii, H.; Towell, RS; Tserruya, I.; Tsuruoka, H.; Tuli, SK; Tydesjo, H.; Tyurin, N.; van Hecke, HW; Velkovska, J.; Velkovsky, M.; Villatte, L.; Vinogradov, AA; Volkov, MA; Vznuzdaev, E.; Wang, XR; Watanabe, Y.; White, SN; Wohn, FK; Woody, CL; Xie, W.; Yang, Y.; Yanovich, A.; Yokkaichi, S.; Young, GR; Yushmanov, IE; Zajc, WA; Zhang, C.; Zhou, S.; Zhou, SJ; Zolin, L.; PHENIX Collaboration.

    2005-01-01

    Within a relativistic transport model for heavy-ion collisions, we show that the recently observed characteristic change from out-of-plane to in-plane elliptic flow of protons in midcentral Au+Au collisions as the incident ...

  7. Contribution of Pi-N-]Lambda-K to Subthreshold Kaon Production in Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Xiong, L.; Ko, Che Ming; Wu, J. Q.

    1990-01-01

    We report the first observation of K-*(892)(0)-->piK in relativistic heavy ion collisions. The transverse momentum spectrum of (K-*0+(K) over bar (*0))/2 from central Au+Au collisions at roots(NN)=130 GeV is presented. The ...

  8. Alternative Size and Lifetime Measurements for High-Energy Heavy-Ion Collisions

    E-Print Network [OSTI]

    Scott Pratt; Silvio Petriconi

    2003-06-16

    Two-Particle correlations based on the interference of identical particles has provided the chief means for determining the shape and lifetime of sources in relativistic heavy ion collisions. Here, Strong and Coulomb induced correlations are shown to provide equivalent information.

  9. Experience with C++ Code Quality in ATLAS

    E-Print Network [OSTI]

    Roe, Shaun; The ATLAS collaboration; Snyder, Scott; Martin-Haugh, Stewart; Obreshkov, Emil; Stewart, Graeme

    2015-01-01

    An explanation of tools used for code quality checking in Atlas offline software, including results and responses is given. The principle tools covered are: Coverity, cppcheck, 'include what you use', Undefined Behaviour Sanitizer

  10. The High Resolution IRAS Galaxy Atlas

    E-Print Network [OSTI]

    Yu Cao; Susan Terebey; Thomas A. Prince; Charles A. Beichman

    1997-06-02

    An atlas of the Galactic plane (-4.7 deg < b < 4.7 deg) plus the molecular clouds in Orion, Rho Oph, and Taurus-Auriga has been produced at 60 and 100 micron from IRAS data. The Atlas consists of resolution-enhanced coadded images having 1 arcmin -- 2 arcmin resolution as well as coadded images at the native IRAS resolution. The IRAS Galaxy Atlas, together with the DRAO HI line / 21 cm continuum and FCRAO CO (1-0) line Galactic plane surveys, both with similar (approx. 1 arcmin) resolution, provide a powerful venue for studying the interstellar medium, star formation and large scale structure in our Galaxy. This paper documents the production and characteristics of the Atlas.

  11. Photoproduction of top in peripheral heavy ion collisions

    E-Print Network [OSTI]

    Spencer R. Klein; Joakim Nystrand; Ramona Vogt

    2001-07-09

    In relativistic heavy ion collisions, top quarks can be produced by photon-gluon fusion when a photon from the Weizs\\"acker-Williams virtual photon field of one nucleus interacts with a gluon in the other nucleus. Photoproduction with heavy ions at the Large Hadron Collider (LHC) will be the first accessible non-hadronic top production channel. We calculate the $t \\bar t$ photoproduction cross sections, pair mass and top quark rapidity distributions in peripheral heavy ion collisions. The cross sections are sensitive to the top quark charge and the large-$Q^2$ gluon distribution in the nucleus. We find a cross section of 94 pb in calcium-calcium collisions, leading to 190 pairs in a one month ($10^6$ sec) LHC run. We also find $p$Pb and $p$Ca cross sections of 5.8 and 3.4 pb respectively, resulting in 6 and 34 $t\\bar t$ pairs per month.

  12. The Spinless Relativistic Yukawa Problem

    E-Print Network [OSTI]

    Wolfgang Lucha; Franz F. Schöberl

    2014-10-20

    Noticing renewed or increasing interest in the possibility to describe semirelativistic bound states (of either spin-zero constituents or, upon confining oneself to spin-averaged features, constituents with nonzero spin) by means of the spinless Salpeter equation generalizing the Schr\\"odinger equation towards incorporation of effects caused by relativistic kinematics, we revisit this problem for interactions between bound-state constituents of Yukawa shape, by recalling and applying several well-known tools enabling to constrain the resulting spectra.

  13. Relativistic tunneling through opaque barriers

    SciTech Connect (OSTI)

    De Leo, Stefano; Leonardi, Vinicius [Department of Applied Mathematics, State University of Campinas, SP 13083-970, Campinas (Brazil)

    2011-02-15

    We propose an analytical study of relativistic tunneling through opaque barriers. We obtain a closed formula for the phase time. This formula is in excellent agreement with the numerical simulations and corrects the standard formula obtained by the stationary phase method. An important result is found when the upper limit of the incoming energy distribution coincides with the upper limit of the tunneling zone. In this case, the phase time is proportional to the barrier width.

  14. WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO-AND MESOSCALE MODELLING

    E-Print Network [OSTI]

    WIND ATLAS FOR EGYPT: MEASUREMENTS, MICRO- AND MESOSCALE MODELLING Niels G. Mortensen1 , Jens atlas based on long-term reanalysis data and a mesoscale model (KAMM). The mean absolute error comparing atlas based on long-term reanalysis data and a mesoscale model, KAMM. The observations have been

  15. Mechanical Model for Relativistic Blast Waves

    E-Print Network [OSTI]

    A. M. Beloborodov; Z. L. Uhm

    2006-09-02

    Relativistic blast waves can be described by a mechanical model. In this model, the "blast" -- the compressed gas between the forward and reverse shocks -- is viewed as one hot body. Equations governing its dynamics are derived from conservation of mass, energy, and momentum. Simple analytical solutions are obtained in the two limiting cases of ultra-relativistic and non-relativistic reverse shock. Equations are derived for the general explosion problem.

  16. Loading Relativistic Maxwell Distributions in Particle Simulations

    E-Print Network [OSTI]

    Zenitani, Seiji

    2015-01-01

    Numerical algorithms to load relativistic Maxwell distributions in particle-in-cell (PIC) and Monte-Carlo simulations are presented. For stationary relativistic Maxwellian, the inverse transform method and the Sobol algorithm are reviewed. To boost particles to obtain relativistic shifted-Maxwellian, two rejection methods are proposed in a physically transparent manner. Their acceptance efficiencies are ${\\approx}50\\%$ for generic cases and $100\\%$ for symmetric distributions. They can be combined with arbitrary base algorithms.

  17. General Relativistic Thermoelectric Effects in Superconductors

    E-Print Network [OSTI]

    B. J. Ahmedov

    2007-01-13

    We discuss the general-relativistic contributions to occur in the electromagnetic properties of a superconductor with a heat flow. The appearance of general-relativistic contribution to the magnetic flux through a superconducting thermoelectric bimetallic circuit is shown. A response of the Josephson junctions to a heat flow is investigated in the general-relativistic framework. Some gravitothermoelectric effects which are observable in the superconducting state in the Earth's gravitational field are considered.

  18. Search for New Physics with Top and Bottom Quarks with ATLAS

    SciTech Connect (OSTI)

    Khanov, Alexander

    2013-12-11

    The studies performed by the principal investigator during the period of the grant constitute the ground work for search for new physics in channels including top and bottom quarks with the ATLAS detector at the Large Hadron Collider. The PI has been involved in search for heavy charged Higgs bosons decaying into top and bottom quark pairs, and top quark rare decays involving Higgs bosons and c-quarks. Both channels have the top quark pair production as their main background, which was studied in detail. The search for heavy charged Higgs and top quark rare decays requires signi#12;cant amount of data accumulated by the experiment. In case no signal is observed in the present data sample collected by ATLAS (5 fb{sup -1} of integrated luminosity at proton-anti proton center-of-mass energy of 7 TeV and 20 fb{sup -1} at 8 TeV), data from the upgraded detector running at 14 TeV needs to be analyzed. The PI has been working on physics and performance studies at upgraded detector.

  19. ATLAS ATLAS ATLAS ATLAS

    E-Print Network [OSTI]

    Gan, K. K.

    Silicon lid v­groove for fibre alignment 45 0 cut for light reflection passive alignment features ffl Silicon carrier cut outs for silicon tiles passive alignment features ffl Silicon tiles alignment marks encouragement, modifications ffl produce a few working packages in­house in the next few weeks ffl investigate

  20. Lagrangian dynamics of submanifolds. Relativistic mechanics

    E-Print Network [OSTI]

    G. Sardanashvily

    2011-12-01

    Geometric formulation of Lagrangian relativistic mechanics in the terms of jets of one-dimensional submanifolds is generalized to Lagrangian theory of submanifolds of arbitrary dimension.

  1. Radiation Damage Monitoring in the ATLAS Pixel Detector1 Sally Seidel, on behalf of the ATLAS Collaborationa,

    E-Print Network [OSTI]

    Seidel, Sally

    Radiation Damage Monitoring in the ATLAS Pixel Detector1 Sally Seidel, on behalf of the ATLAS; radiation damage; silicon10 1. Introduction11 The innermost detection system of the ATLAS Detector [1 to respond to these changes, the radiation damage sustained by detector22 elements must be monitored.23

  2. ATLAS Distributed Data Analysis: challenges and performance

    E-Print Network [OSTI]

    Fassi, Farida; The ATLAS collaboration

    2015-01-01

    In the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the...

  3. ATLAS Distributed Data Analysis: performance and challenges

    E-Print Network [OSTI]

    Fassi, Farida; The ATLAS collaboration

    2015-01-01

    In the LHC operations era the key goal is to analyse the results of the collisions of high-energy particles as a way of probing the fundamental forces of nature. The ATLAS experiment at the LHC at CERN is recording and simulating several 10's of PetaBytes of data per year. The ATLAS Computing Model was designed around the concepts of Grid Computing. Large data volumes from the detectors and simulations require a large number of CPUs and storage space for data processing. To cope with this challenge a global network known as the Worldwide LHC Computing Grid (WLCG) was built. This is the most sophisticated data taking and analysis system ever built. ATLAS accumulated more than 140 PB of data between 2009 and 2014. To analyse these data ATLAS developed, deployed and now operates a mature and stable distributed analysis (DA) service on the WLCG. The service is actively used: more than half a million user jobs run daily on DA resources, submitted by more than 1500 ATLAS physicists. A significant reliability of the...

  4. Renewable energy atlas of the United States.

    SciTech Connect (OSTI)

    Kuiper, J.A.; Hlava, K.Greenwood, H.; Carr, A.

    2012-05-01

    The Renewable Energy Atlas (Atlas) of the United States is a compilation of geospatial data focused on renewable energy resources, federal land ownership, and base map reference information. It is designed for the U.S. Department of Agriculture Forest Service (USFS) and other federal land management agencies to evaluate existing and proposed renewable energy projects. Much of the content of the Atlas was compiled at Argonne National Laboratory (Argonne) to support recent and current energy-related Environmental Impact Statements and studies, including the following projects: (1) West-wide Energy Corridor Programmatic Environmental Impact Statement (PEIS) (BLM 2008); (2) Draft PEIS for Solar Energy Development in Six Southwestern States (DOE/BLM 2010); (3) Supplement to the Draft PEIS for Solar Energy Development in Six Southwestern States (DOE/BLM 2011); (4) Upper Great Plains Wind Energy PEIS (WAPA/USFWS 2012, in progress); and (5) Energy Transport Corridors: The Potential Role of Federal Lands in States Identified by the Energy Policy Act of 2005, Section 368(b) (in progress). This report explains how to add the Atlas to your computer and install the associated software; describes each of the components of the Atlas; lists the Geographic Information System (GIS) database content and sources; and provides a brief introduction to the major renewable energy technologies.

  5. Beam Dynamics Issues in an Extended Relativistic Klystron

    E-Print Network [OSTI]

    Giordano, G.

    2008-01-01

    in an Extended Relativistic Klystron G. Giordano, H. Li, N.in an Extended Relativistic Klystron" G. Giordano, H. Li, N.an Extended Relativistic Klystron* G. Giordano t , H. Li, N.

  6. Chaotic distributions for relativistic particles

    E-Print Network [OSTI]

    Dawan Mustafa; Bernt Wennberg

    2015-03-16

    We study a modified Kac model where the classical kinetic energy is replaced by an arbitrary energy function $\\phi(v)$, $v\\in\\mathbb{R}$. The aim of this paper is to show that the uniform distribution with respect to the microcanonical measure is $Ce^{-z_0\\phi(v)} $-chaotic, $C,z_0\\in\\mathbb{R}_{+}$. The kinetic energy for relativistic particles is a special case. A generalization to the case $v\\in \\mathbb{R}^d$ which involves conservation momentum is also formally discussed.

  7. Relativistic Laser-Matter Interactions

    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) by Carbon-RichProtonAbout UsRegional companies eyeRelativistic

  8. The Evolution of Cloud Computing in ATLAS

    E-Print Network [OSTI]

    Taylor, Ryan P; The ATLAS collaboration; Brasolin, Franco; Cordeiro, Cristovao; Desmarais, Ron; Field, Laurence; Gable, Ian; Giordano, Domenico; Di Girolamo, Alessandro; Hover, John; Leblanc, Matthew Edgar; Love, Peter; Paterson, Michael; Sobie, Randall; Zaytsev, Alexandr

    2015-01-01

    The ATLAS experiment has successfully incorporated cloud computing technology and cloud resources into its primarily grid-based model of distributed computing. Cloud R&D activities continue to mature and transition into stable production systems, while ongoing evolutionary changes are still needed to adapt and refine the approaches used, in response to changes in prevailing cloud technology. In addition, completely new developments are needed to handle emerging requirements. This paper describes the overall evolution of cloud computing in ATLAS. The current status of the virtual machine (VM) management systems used for harnessing infrastructure as a service (IaaS) resources are discussed. Monitoring and accounting systems tailored for clouds are needed to complete the integration of cloud resources within ATLAS' distributed computing framework. We are developing and deploying new solutions to address the challenge of operation in a geographically distributed multi-cloud scenario, including a system for ma...

  9. The Evolution of Cloud Computing in ATLAS

    E-Print Network [OSTI]

    Taylor, Ryan P.; The ATLAS collaboration; Love, Peter; Leblanc, Matthew Edgar; Di Girolamo, Alessandro; Paterson, Michael; Gable, Ian; Sobie, Randall; Field, Laurence

    2015-01-01

    The ATLAS experiment has successfully incorporated cloud computing technology and cloud resources into its primarily grid-based model of distributed computing. Cloud R&D activities continue to mature and transition into stable production systems, while ongoing evolutionary changes are still needed to adapt and refine the approaches used, in response to changes in prevailing cloud technology. In addition, completely new developments are needed to handle emerging requirements. This work will describe the overall evolution of cloud computing in ATLAS. The current status of the VM management systems used for harnessing IAAS resources will be discussed. Monitoring and accounting systems tailored for clouds are needed to complete the integration of cloud resources within ATLAS' distributed computing framework. We are developing and deploying new solutions to address the challenge of operation in a geographically distributed multi-cloud scenario, including a system for managing VM images across multiple clouds, ...

  10. Heavy-flavor transport

    E-Print Network [OSTI]

    Andrea Beraudo

    2015-10-29

    The formation of a hot deconfined medium (Quark-Gluon Plasma) in high-energy nuclear collisions affects heavy-flavor observables. In the low/moderate-pT range transport calculations allow one to simulate the propagation of heavy quarks in the plasma and to evaluate the effect of the medium on the final hadronic spectra: results obtained with transport coefficients arising from different theoretical approaches can be compared to experimental data. Finally, a discussion of possible effects on heavy-flavor observables due to the possible formation of a hot-medium in small systems (like in p-A collisions) is presented.

  11. Collective Dynamics and Coherent Diagnostics of Microbunched Relativistic Electron Beams

    E-Print Network [OSTI]

    Marinelli, Agostino

    2012-01-01

    Brightness Relativistic Electron Beams for Free-Electrona Thermal Relativistic Electron Beam: Eigenvalue/Eigenmodemicrobunching in the electron beam. The microbunched

  12. 221B Lecture Notes Relativistic Quantum Mechanics

    E-Print Network [OSTI]

    Murayama, Hitoshi

    221B Lecture Notes Relativistic Quantum Mechanics 1 Need for Relativistic Quantum Mechanics We r + dx 1 8 (E2 + B2 ). (1) (Coulomb potential is there only if there is another static charged, similarly to the Newton's equation of motion in mechanics. The initial condtions to solve the Newton

  13. 129 Lecture Notes Relativistic Quantum Mechanics

    E-Print Network [OSTI]

    Murayama, Hitoshi

    129 Lecture Notes Relativistic Quantum Mechanics 1 Need for Relativistic Quantum Mechanics2 ). (1) (Coulomb potential is there only if there is another static charged particle's equation of motion in mechanics. The initial condtions to solve the Newton's equation of motion

  14. 221B Lecture Notes Relativistic Quantum Mechanics

    E-Print Network [OSTI]

    Murayama, Hitoshi

    221B Lecture Notes Relativistic Quantum Mechanics 1 Need for Relativistic Quantum Mechanics We r + dx 1 8 (E2 + B2 ). (1) (Coulomb potential is there only if there is another static charged's equation of motion in mechanics. The initial condtions to solve the Newton's equation of motion

  15. Relativistic self-focusing in underdense plasma

    SciTech Connect (OSTI)

    Feit, M. D.; Garrison, J. C.; Rubenchik, A. M.; Komashko, A.; Musher, S. L.; Turitsyn, S. K.

    1997-04-15

    An improved cavitation model shows that stable beam channeling and electron cavitation occur for relativistic laser intensities even at powers hundreds of times larger than the critical power for self-focusing. Numerical calculations for long pulses (100 ps) demonstrate strong self-focusing at weakly relativistic intensities. The destructive effects of self-focusing are increasingly suppressed at high intensity.

  16. Relativistic distribution function for particles with spin at local thermodynamical equilibrium

    SciTech Connect (OSTI)

    Becattini, F., E-mail: becattini@fi.infn.it [Università di Firenze, Florence (Italy); INFN Sezione di Firenze, Florence (Italy); Universität Frankfurt, Frankfurt am Main (Germany); FIAS, Frankfurt am Main (Germany)] [Germany; Chandra, V., E-mail: vinod.chandra@fi.infn.it [INFN Sezione di Firenze, Florence (Italy); Del Zanna, L., E-mail: ldz@arcetri.astro.it [Università di Firenze, Florence (Italy); INFN Sezione di Firenze, Florence (Italy); Grossi, E., E-mail: grossi@fi.infn.it [Università di Firenze, Florence (Italy); INFN Sezione di Firenze, Florence (Italy)

    2013-11-15

    We present an extension of relativistic single-particle distribution function for weakly interacting particles at local thermodynamical equilibrium including spin degrees of freedom, for massive spin 1/2 particles. We infer, on the basis of the global equilibrium case, that at local thermodynamical equilibrium particles acquire a net polarization proportional to the vorticity of the inverse temperature four-vector field. The obtained formula for polarization also implies that a steady gradient of temperature entails a polarization orthogonal to particle momentum. The single-particle distribution function in momentum space extends the so-called Cooper–Frye formula to particles with spin 1/2 and allows us to predict their polarization in relativistic heavy ion collisions at the freeze-out. -- Highlights: •Single-particle distribution function in local thermodynamical equilibrium with spin. •Polarization of spin 1/2 particles in a fluid at local thermodynamical equilibrium. •Prediction of a new effect: a steady gradient of temperature induces a polarization. •Application to the calculation of polarization in relativistic heavy ion collisions.

  17. Triggering events with GPU at ATLAS

    E-Print Network [OSTI]

    Kama, Sami; The ATLAS collaboration

    2015-01-01

    The growing complexity of events produced in LHC collisions demands more and more computing power both for the on line selection and for the offline reconstruction of events. In recent years, the explosive performance growth of massively parallel processors like Graphical Processing Units both in computing power and in low energy consumption, make GPU extremely attractive for using them in a complex high energy experiment like ATLAS. Together with the optimization of reconstruction algorithms exploiting this new massively parallel paradigm, a small scale prototype of the full ATLAS High Level Trigger exploiting GPU has been implemented. We discuss the integration procedure of this prototype, the achieved performance and the prospects for the future.

  18. Atlas of major Appalachian basin gas plays

    SciTech Connect (OSTI)

    Aminian, K.; Avary, K.L.; Baranoski, M.T.; Flaherty, K.; Humphreys, M.; Smosna, R.A.

    1995-06-01

    This regional study of gas reservoirs in the Appalachian basin has four main objectives: to organize all of the -as reservoirs in the Appalachian basin into unique plays based on common age, lithology, trap type and other geologic similarities; to write, illustrate and publish an atlas of major gas plays; to prepare and submit a digital data base of geologic, engineering and reservoir parameters for each gas field; and technology transfer to the oil and gas industry during the preparation of the atlas and data base.

  19. Process for removing heavy metal compounds from heavy crude oil

    DOE Patents [OSTI]

    Cha, Chang Y. (Golden, CO); Boysen, John E. (Laramie, WY); Branthaver, Jan F. (Laramie, WY)

    1991-01-01

    A process is provided for removing heavy metal compounds from heavy crude oil by mixing the heavy crude oil with tar sand; preheating the mixture to a temperature of about 650.degree. F.; heating said mixture to up to 800.degree. F.; and separating tar sand from the light oils formed during said heating. The heavy metals removed from the heavy oils can be recovered from the spent sand for other uses.

  20. Heavy Hybrid mesons Masses

    E-Print Network [OSTI]

    F. Iddir; L. Semlala

    2006-11-25

    We estimate the ground state masses of the heavy hybrid mesons using a phenomenological QCD-type potential. 0^{- -},1^{- -},0^{- +},1^{- +} and 0^{+ -} J^{PC} states are considered.

  1. HEAVY ION INERTIAL FUSION

    E-Print Network [OSTI]

    Keefe, D.

    2008-01-01

    Accelerators as Drivers for Inertially Confined Fusion, W.B.LBL-9332/SLAC-22l (1979) Fusion Driven by Heavy Ion Beams,OF CALIFORNIA f Accelerator & Fusion Research Division

  2. HEAVY QUARKS JETS

    E-Print Network [OSTI]

    Suzuki, M.

    2010-01-01

    i'iAsm Heavy Quark Jets iBirijets. Short-distance vs long-than a few wide angle sub-jets at to draw first skelton jet

  3. Elliptic flow of thermal photons in relativistic nuclear collisions

    E-Print Network [OSTI]

    Rupa Chatterjee; Evan S. Frodermann; Ulrich W. Heinz; Dinesh K. Srivastava

    2006-04-09

    We predict the transverse momentum (pT) dependence of elliptic flow of thermal photons for Au+Au collisions at the Relativistic Heavy Ion Collider. We model the system hydrodynamically, assuming formation of a thermalized quark-gluon plasma at some early time, followed by cooling through expansion, hadronization and decoupling. Photons are emitted throughout the expansion history. Contrary to hadron elliptic flow, which hydrodynamics predicts to increase monotonically with pT, the elliptic flow of thermal photons is predicted to first rise and then fall again as pT increases. Photon elliptic flow at high pT is shown to reflect the quark momentum anisotropy at early times when it is small, whereas at low pT it is controlled by the much larger pion momentum anisotropy during the late hadronic emission stage. An interesting structure is predicted at intermediate pT ~ 0.4 GeV/c where photon elliptic flow reflects the momenta and the (compared to pions) reduced v2 of heavy vector mesons in the late hadronic phase.

  4. Relativistic Nuclear Energy Density Functionals: adjusting parameters to binding energies

    E-Print Network [OSTI]

    T. Niksic; D. Vretenar; P. Ring

    2008-09-08

    We study a particular class of relativistic nuclear energy density functionals in which only nucleon degrees of freedom are explicitly used in the construction of effective interaction terms. Short-distance (high-momentum) correlations, as well as intermediate and long-range dynamics, are encoded in the medium (nucleon density) dependence of the strength functionals of an effective interaction Lagrangian. Guided by the density dependence of microscopic nucleon self-energies in nuclear matter, a phenomenological ansatz for the density-dependent coupling functionals is accurately determined in self-consistent mean-field calculations of binding energies of a large set of axially deformed nuclei. The relationship between the nuclear matter volume, surface and symmetry energies, and the corresponding predictions for nuclear masses is analyzed in detail. The resulting best-fit parametrization of the nuclear energy density functional is further tested in calculations of properties of spherical and deformed medium-heavy and heavy nuclei, including binding energies, charge radii, deformation parameters, neutron skin thickness, and excitation energies of giant multipole resonances.

  5. Real-time flavour tagging selection in ATLAS

    E-Print Network [OSTI]

    Bertella, Claudia; The ATLAS collaboration

    2015-01-01

    In high-energy physics experiments, online selection is crucial to identify the few interesting collisions from the large data volume processed. In the overall ATLAS trigger strategy, b-jet triggers are designed to identify heavy-flavor content in real-time and, in particular, provide the only option to efficiently record events with fully hadronic final states containing b-jets. In doing so, two different, but related, challenges are faced. The physics goal is to optimise as far as possible the rejection of light jets from QCD processes, while retaining a high efficiency on selecting jets from beauty, while maintaining affordable trigger rates without raising jet energy thresholds. This maps into a challenging computing task, as charged tracks and their corresponding vertexes must be reconstructed and analysed for each jet above the desired threshold, regardless of the increasingly harsh pile-up conditions. The performance of b-jet triggers during the LHC Run 1 data-taking campaigns is presented, together wi...

  6. Real-time flavour tagging selection in ATLAS

    E-Print Network [OSTI]

    Bogavac, Danijela; The ATLAS collaboration

    2015-01-01

    In high-energy physics experiments, online selection is crucial to identify the few interesting collisions from the large data volume processed. In the overall ATLAS trigger strategy, b-jet triggers are designed to identify heavy-flavour content in real-time and, in particular, provide the only option to efficiently record events with fully hadronic final states containing b-jets. In doing so, two different, but related, challenges are faced. The physics goal is to optimise as far as possible the rejection of light jets from multijet processes, while retaining a high efficiency on selecting jets from beauty, and maintaining affordable trigger rates without raising jet energy thresholds. This maps into a challenging computing task, as charged tracks and their corresponding vertexes must be reconstructed and analysed for each jet above the desired threshold, regardless of the increasingly harsh pile-up conditions. The performance of b-jet triggers during the LHC Run 1 data-taking campaigns is presented, togethe...

  7. Accelerating Solutions of Perfect Fluid Hydrodynamics for Initial Energy Density and Life-Time Measurements in Heavy Ion Collisions

    E-Print Network [OSTI]

    T. Csorgo; M. I. Nagy; M. Csanad

    2007-04-17

    A new class of accelerating, exact, explicit and simple solutions of relativistic hydrodynamics is presented. Since these new solutions yield a finite rapidity distribution, they lead to an advanced estimate of the initial energy density and life-time of high energy heavy ion reactions. Accelerating solutions are also given for spherical expansions in arbitrary number of spatial dimensions.

  8. Parton energy loss in heavy-ion collisions via direct-photon and charged-particle azimuthal correlations

    E-Print Network [OSTI]

    Balewski, Jan T.

    Charged-particle spectra associated with direct photon (?dir) and pi0 are measured in p+p and Au+Au collisions at center-of-mass energy [sqrt]sNN=200 GeV with the STAR detector at the Relativistic Heavy Ion Collider. A ...

  9. United States Atlas of Renewable Resources

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

    The Atlas is an interactive application of the renewable energy resources in the contiguous United States, Alaska and Hawaii. It illustrates the geographic distribution of wind, solar, geothermal, and biomass resources, as well as other pertinent information such as transportation network and administrative boundaries.[Copied from http://www.nrel.gov/gis/maps.html

  10. ATLAS e-News 1 November 2010

    E-Print Network [OSTI]

    Dettweiler, Michael

    the outside', even your close family and friends, what it means to be a working particle physicist ­ what of science education, scientific research, policy-making and curriculum development. The new initiative collaborations. Over the next three years, Learning with ATLAS@CERN will instigate a gearshift by actually

  11. Relativistic MOND from Modified Energetics

    E-Print Network [OSTI]

    Durmus Ali Demir; Canan Nurhan Karahan

    2014-08-22

    We begin to investigate the question of what modifications in energy-momentum tensor can yield correct MOND regime. As a starting study, we refrain from insisting on an action principle and focus exclusively on the equations of motion. The present work, despite the absence of an explicit action functional, can be regarded to extend Milgrom's modified inertia approach to relativistic domain. Our results show that a proper MOND limit arises if energy-momentum tensor is modified to involve determinant of the metric tensor in reference to the flat metric, where the latter is dynamically generated as in gravitational Higgs mechanism. This modified energy-momentum tensor is conserved in both Newtonian and MONDian regimes.

  12. Relativistic MOND from Modified Energetics

    E-Print Network [OSTI]

    Demir, Durmus Ali

    2014-01-01

    We begin to investigate the question of what modifications in energy-momentum tensor can yield correct MOND regime. As a starting study, we refrain from insisting on an action principle and focus exclusively on the equations of motion. The present work, despite the absence of an explicit action functional, can be regarded to extend Milgrom's modified inertia approach to relativistic domain. Our results show that a proper MOND limit arises if energy-momentum tensor is modified to involve determinant of the metric tensor in reference to the flat metric, where the latter is dynamically generated as in gravitational Higgs mechanism. This modified energy-momentum tensor is conserved in both Newtonian and MONDian regimes.

  13. Complete relativistic second-order dissipative hydrodynamics from the entropy principle

    E-Print Network [OSTI]

    Jaiswal, Amaresh; Pal, Subrata

    2013-01-01

    We present a new derivation of relativistic dissipative hydrodynamic equations, which invokes the second law of thermodynamics for the entropy four-current expressed in terms of the single-particle phase-space distribution function obtained from Grad's 14-moment approximation. This derivation is complete in the sense that all the second-order transport coefficients are uniquely determined within a single theoretical framework. In particular, this removes the long-standing ambiguity in the relaxation time for bulk viscosity thereby eliminating one of the uncertainties in the extraction of the shear viscosity to entropy density ratio from confrontation with the anisotropic flow data in relativistic heavy-ion collisions. We find that in the one-dimensional scaling expansion, these transport coefficients prevent the occurrence of cavitation even for rather large values of the bulk viscosity estimated in lattice QCD.

  14. Complete relativistic second-order dissipative hydrodynamics from the entropy principle

    E-Print Network [OSTI]

    Amaresh Jaiswal; Rajeev S. Bhalerao; Subrata Pal

    2013-02-04

    We present a new derivation of relativistic dissipative hydrodynamic equations, which invokes the second law of thermodynamics for the entropy four-current expressed in terms of the single-particle phase-space distribution function obtained from Grad's 14-moment approximation. This derivation is complete in the sense that all the second-order transport coefficients are uniquely determined within a single theoretical framework. In particular, this removes the long-standing ambiguity in the relaxation time for bulk viscosity thereby eliminating one of the uncertainties in the extraction of the shear viscosity to entropy density ratio from confrontation with the anisotropic flow data in relativistic heavy-ion collisions. We find that in the one-dimensional scaling expansion, these transport coefficients prevent the occurrence of cavitation even for rather large values of the bulk viscosity estimated in lattice QCD.

  15. Toward the Limits of Matter: Ultra-relativistic nuclear collisions at CERN

    E-Print Network [OSTI]

    Jurgen Schukraft; Reinhard Stock

    2015-05-26

    Strongly interacting matter as described by the thermodynamics of QCD undergoes a phase transition, from a low temperature hadronic medium to a high temperature quark-gluon plasma state. In the early universe this transition occurred during the early microsecond era. It can be investigated in the laboratory, in collisions of nuclei at relativistic energy, which create "fireballs" of sufficient energy density to cross the QCD Phase boundary. We describe 3 decades of work at CERN, devoted to the study of the QCD plasma and the phase transition. From modest beginnings at the SPS, ultra-relativistic heavy ion physics has evolved today into a central pillar of contemporary nuclear physics and forms a significant part of the LHC program.

  16. A Relativistic Dynamical Collapse Model

    E-Print Network [OSTI]

    Philip Pearle

    2014-12-21

    A model is discussed where all operators are constructed from a quantum scalar field whose energy spectrum takes on all real values. The Schr\\"odinger picture wave function depends upon space and time coordinates for each particle, as well as an inexorably increasing evolution parameter $s$ which labels a foliation of space-like hypersurfaces. The model is constructed to be manifestly Lorentz invariant in the interaction picture. Free particle states and interactions are discussed in this framework. Then, the formalism of the CSL (Continuous Spontaneous Localization) theory of dynamical collapse is applied. The collapse-generating operator is chosen to to be the particle number space-time density. Unlike previous relativistically invariant models, the vacuum state is not excited. The collapse dynamics depends upon two parameters, a parameter $\\Lambda$ which represents the collapse rate/volume and a scale factor $\\ell$. A common example of collapse dynamics, involving a clump of matter in a superposition of two locations, is analyzed. The collapse rate is shown to be identical to that of non-relativistic CSL when the GRW-CSL choice of $\\ell=a=10^{-5}$cm, is made, along with $\\Lambda=\\lambda/a^{3}$ (GRW-CSL choice $\\lambda=10^{-16}s^{-1}$). However, it is also shown that the change of mass of a nucleon over the age of the universe is then unacceptably large. The case where $\\ell$ is the size of the universe is then considered. It is shown that the collapse behavior is satisfactory and the change of mass over the age of the universe is acceptably small, when $\\Lambda= \\lambda/\\ell a^{2}$.

  17. Path Integral Monte-Carlo Calculations for Relativistic Oscillator

    E-Print Network [OSTI]

    Alexandr Ivanov; Oleg Pavlovsky

    2014-11-11

    The problem of Relativistic Oscillator has been studied in the framework of Path Integral Monte-Carlo(PIMC) approach. Ultra-relativistic and non-relativistic limits have been discussed. We show that PIMC method can be effectively used for investigation of relativistic systems.

  18. Analytical models of relativistic accretion disks

    E-Print Network [OSTI]

    Viacheslav V. Zhuravlev

    2015-09-24

    We present not a literature review but a description, as detailed and consistent as possible, of two analytic models of disk accretion onto a rotating black hole: a standard relativistic disk and a twisted relativistic disk. Although one of these models is much older than the other, both are of topical current interest for black hole studies. The way the exposition is presented, the reader with only a limited knowledge of general relativity and relativistic hydrodynamics can --- with little or no use of additional sources -- gain good insight into many technical details lacking in the original papers.

  19. Five Years of Tracking Heavy Ion Collisions at RHIC

    E-Print Network [OSTI]

    A. Franz

    2006-03-13

    Five years have passed since the first collisions of Au nuclei at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory (BNL) on Long Island. With nucleon-nucleon center-of-mass energies of up to sqrt(s_NN)=200GeV RHIC provides the highest energy heavy ion collisions at any existing collider. To study the dynamics of nuclear matter at extreme temperatures and pressures hundreds of produced particles need to be tracked and identified, which provides a sizable challenge to the four experiments. This article tries to summarize these first years of RHIC operation from the detector point of view and give a glimpse at the future of the accelerator and its experiments.

  20. Selected experimental results from heavy-ion collisions at LHC

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

    Singh, Ranbir; Kumar, Lokesh; Netrakanti, Pawan Kumar; Mohanty, Bedangadas

    2013-01-01

    We review a subset of experimental results from the heavy-ion collisions at the Large Hadron Collider (LHC) facility at CERN. Excellent consistency is observed across all the experiments at the LHC (at center of mass energysNN=2.76 TeV) for the measurements such as charged particle multiplicity density, azimuthal anisotropy coefficients, and nuclear modification factor of charged hadrons. Comparison to similar measurements from the Relativistic Heavy Ion Collider (RHIC) at lower energy (sNN=200 GeV) suggests that the system formed at LHC has a higher energy density and larger system size and lives for a longer time. These measurements aremore »compared to model calculations to obtain physical insights on the properties of matter created at the RHIC and LHC.« less

  1. Finite volume effects for nucleon and heavy meson masses

    SciTech Connect (OSTI)

    Colangelo, Gilberto; Fuhrer, Andreas; Lanz, Stefan

    2010-08-01

    We apply the resummed version of the Luescher formula to analyze finite volume corrections to the mass of the nucleon and of heavy mesons. We show that by applying the subthreshold expansion of the scattering amplitudes one can express the finite volume corrections in terms of only a few physical observables and the size of the box. In the case of the nucleon, the available information about the quark mass dependence of these physical quantities is discussed and used to assess the finite volume corrections to the nucleon mass as a function of the quark mass including a detailed analysis of the remaining uncertainties. For heavy mesons, the Luescher formula is derived both fully relativistically and in a nonrelativistic approximation and a first attempt at a numerical analysis is made.

  2. Factorized power expansion for high-$p_T$ heavy quarkonium production

    E-Print Network [OSTI]

    Ma, Yan-Qing; Sterman, George; Zhang, Hong

    2014-01-01

    We show that when the factorized cross section for heavy quarkonium production includes next-to-leading power (NLP) contributions associated with the production of the heavy quark pair at short distances, it naturally reproduces all high $p_T$ results calculated in non-relativistic QCD (NRQCD) factorization. This extended formalism requires fragmentation functions for heavy quark pairs, as well as for light partons. When these fragmentation functions are themselves calculated using NRQCD, we find that two of the four leading NRQCD production channels, ${^3\\hspace{-0.6mm}S_{1}^{[1]}}$ and ${^1\\hspace{-0.6mm}S_{0}^{[8]}}$, are dominated by the NLP contributions for a very wide $p_T$ range. The large next-to-leading order corrections of NRQCD are absorbed into the leading order of the first power correction. The impact of this finding on the heavy quarkonium production and its polarization is discussed.

  3. Factorized power expansion for high-$p_T$ heavy quarkonium production

    E-Print Network [OSTI]

    Yan-Qing Ma; Jian-Wei Qiu; George Sterman; Hong Zhang

    2014-10-11

    We show that when the factorized cross section for heavy quarkonium production includes next-to-leading power (NLP) contributions associated with the production of the heavy quark pair at short distances, it naturally reproduces all high $p_T$ results calculated in non-relativistic QCD (NRQCD) factorization. This extended formalism requires fragmentation functions for heavy quark pairs, as well as for light partons. When these fragmentation functions are themselves calculated using NRQCD, we find that two of the four leading NRQCD production channels, ${^3\\hspace{-0.6mm}S_{1}^{[1]}}$ and ${^1\\hspace{-0.6mm}S_{0}^{[8]}}$, are dominated by the NLP contributions for a very wide $p_T$ range. The large next-to-leading order corrections of NRQCD are absorbed into the leading order of the first power correction. The impact of this finding on the heavy quarkonium production and its polarization is discussed.

  4. Vortex in a weakly relativistic Bose gas at zero temperature and relativistic fluid approximation

    E-Print Network [OSTI]

    B. Boisseau

    2004-09-14

    The Bogoliubov procedure in quantum field theory is used to describe a relativistic almost ideal Bose gas at zero temperature. Special attention is given to the study of a vortex. The radius of the vortex in the field description is compared to that obtained in the relativistic fluid approximation. The Kelvin waves are studied and, for long wavelengths, the dispersion relation is obtained by an asymptotic matching method and compared with the non relativistic result.

  5. 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...

  6. LIPS-thermalization of a relativistic gas

    E-Print Network [OSTI]

    Vladimír Balek

    2011-01-31

    It is argued that two-particle collisions of relativistic particles "at a distance", irrespective of their position in the configuration space, generate uniform distribution of particles in Lorentz invariant phase space.

  7. Star Products for Relativistic Quantum Mechanics

    E-Print Network [OSTI]

    P. Henselder

    2007-05-24

    The star product formalism has proved to be an alternative formulation for nonrelativistic quantum mechanics. We want introduce here a covariant star product in order to extend the star product formalism to relativistic quantum mechanics in the proper time formulation.

  8. A powerful hydrodynamic booster for relativistic jets

    E-Print Network [OSTI]

    Miguel A. Aloy; Luciano Rezzolla

    2006-02-20

    Velocities close to the speed of light are a robust observational property of the jets observed in microquasars and AGNs, and are expected to be behind much of the phenomenology of GRBs. Yet, the mechanism boosting relativistic jets to such large Lorentz factors is still essentially unknown. Building on recent general-relativistic, multidimensional simulations of progenitors of short GRBs, we discuss a new effect in relativistic hydrodynamics which can act as an efficient booster in jets. This effect is purely hydrodynamical and occurs when large velocities tangential to a discontinuity are present in the flow, yielding Lorentz factors $\\Gamma \\sim 10^2-10^3$ or larger in flows with moderate initial Lorentz factors. Although without a Newtonian counterpart, this effect can be explained easily through the most elementary hydrodynamical flow: i.e., a relativistic Riemann problem.

  9. Charged Particle Multiplicities in Ultra-relativistic Au+Au and Cu+Cu Collisions

    E-Print Network [OSTI]

    B. B. Back

    2006-04-26

    The PHOBOS collaboration has carried out a systematic study of charged particle multiplicities in Cu+Cu and Au+Au collisions at the Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National Laboratory. A unique feature of the PHOBOS detector is its ability to measure charged particles over a very wide angular range from 0.5 to 179.5 deg. corresponding to |eta|<5.4. The general features of the charged particle multiplicity distributions as a function of pseudo-rapidity, collision energy and centrality, as well as system size, are discussed.

  10. Correlations of electrons from heavy flavor decay in p+p, d+Au and Au+Au collisions

    E-Print Network [OSTI]

    Anne Sickles; for the PHENIX Collaboration

    2010-07-14

    In relativistic heavy ion collisions heavy flavor probes are crucial to understand the interactions between partons and the produced hot nuclear matter. Measurements in p+p collisions provide information about how the heavy quarks are produced and fragment and in d+Au collisions are sensitive to possible effects from cold nuclear matter. Azimuthal correlation measurements involving heavy flavor probes are complementary to single particle spectra measurements and provide additional information about production and interactions of heavy quarks. Measurements of electrons with heavy flavor decay with other hadrons from the event can provide information about how the heavy quark interacts with the produced matter and can be compared to similar measurements from light hadron correlations. Correlations between electrons from heavy flavor decay with muons, also from heavy flavor decay, can provide further information about heavy flavor production and cold nuclear matter effects in d+Au collisions with a very clean signal. We present PHENIX results for electron-hadron correlations in p+p and Au+Au collisions and electron-muon correlations in p+p and d+Au collisions and discuss the implications of these measurements.

  11. Deriving Mathisson - Papapetrou equations from relativistic pseudomechanics

    E-Print Network [OSTI]

    R. R. Lompay

    2005-03-12

    It is shown that the equations of motion of a test point particle with spin in a given gravitational field, so called Mathisson - Papapetrou equations, can be derived from Euler - Lagrange equations of the relativistic pseudomechanics -- relativistic mechanics, which side by side uses the conventional (commuting) and Grassmannian (anticommuting) variables. In this approach the known difficulties of the Mathisson - Papapetrou equations, namely, the problem of the choice of supplementary conditions and the problem of higher derivatives are not appear.

  12. Stochastic Particle Acceleration in Parallel Relativistic Shocks

    E-Print Network [OSTI]

    Joni J. P. Virtanen; Rami Vainio

    2005-03-03

    We present results of test-particle simulations on both the first- and the second-order Fermi acceleration for relativistic parallel shock waves. Our studies suggest that the role of the second-order mechanism in the turbulent downstream of a relativistic shock may have been underestimated in the past, and that the stochastic mechanism may have significant effects on the form of the particle spectra and its time evolution.

  13. General Relativistic Hydrodynamics on Overlapping Curvilinear Grids

    E-Print Network [OSTI]

    Blakely, P. M.; Nikiforakis, N.; Henshaw, W. D.

    2015-03-04

    the simplification of the equation for conservation of energy and momentum, T ??;? = 0, to the linear wave equation ?;? ? = 0 (although we note that not all solutions of the linear wave equation result in physically valid stiff-fluid solutions). 2.2. Ideal fluid... disks – hydrodynamics – shock waves 1. Introduction The simulation of general relativistic hydrodynamical (GRHD) problems is of great importance to the astrophysics commu- nity. Although special relativistic and post Newtonian approx- imations can...

  14. Relativistic self-focusing in underdense plasma

    SciTech Connect (OSTI)

    Feit, M.D.; Garrison, J.C.; Rubenchik, A.M.; Musher, S.L.; Turitsyn, S.K.

    1997-04-01

    An improved cavitation model shows that stable beam channeling and electron cavitation occur for relativistic laser intensities even at powers hundreds of times larger than the critical power for self-focusing. Numerical calculations for long pulses (100 ps) demonstrate strong self-focusing at weakly relativistic intensities. The destructive effects of self-focusing are increasingly suppressed at high intensity. {copyright} {ital 1997 American Institute of Physics.}

  15. Heavy Tetraquarks in the Diquark-Antidiquark Picture

    E-Print Network [OSTI]

    Hadizadeh, M R

    2015-01-01

    The homogeneous Lippmann-Schwinger integral equation is solved in momentum space to calculate the masses of heavy tetraquarks with hidden charm and bottom. The tetraquark bound states are studied in the diquark-antidiquark picture as a two-body problem. A regularized form of the diquark-antidiquark potential is used to overcome the singularity of the confining potential at large distances or small momenta. Our numerical results indicate that the relativistic effect leads to a small reduction in the mass of heavy tetraquarks, which is less than $2\\,\\%$ for charm and less than $0.2\\,\\%$ for bottom tetraquarks. The calculated masses of heavy tetraquarks for $1s$, $1p$, $2s$, $1d$ and $2p$ states are in good agreement with other theoretical calculations and experimental data. Our numerical analysis predict the masses of heavy tetraquarks for $3s$, $2d$ and $3p$ states for the first time, and we are not aware of any other theoretical results or experimental data for these states.

  16. $O(a^2)$-improved actions for heavy quarks and scaling studies on quenched lattices

    E-Print Network [OSTI]

    Yong-Gwi Cho; Shoji Hashimoto; Jun-Ichi Noaki; Andreas Jüttner; Marina Marinkovic

    2013-12-17

    We investigate a new class of improved relativistic fermion action on the lattice with a criterion to give excellent energy-momentum dispersion relation as well as to be consistent with tree-level $O\\left(a^{2}\\right)$-improvement. Main application in mind is that for heavy quark for which $ma\\simeq O(0.5)$. We present tree-level results and a scaling study on quenched lattices.

  17. $O(a^2)$-improved actions for heavy quarks and scaling studies on quenched lattices

    E-Print Network [OSTI]

    Cho, Yong-Gwi; Noaki, Jun-Ichi; Jüttner, Andreas; Marinkovic, Marina

    2013-01-01

    We investigate a new class of improved relativistic fermion action on the lattice with a criterion to give excellent energy-momentum dispersion relation as well as to be consistent with tree-level $O\\left(a^{2}\\right)$-improvement. Main application in mind is that for heavy quark for which $ma\\simeq O(0.5)$. We present tree-level results and a scaling study on quenched lattices.

  18. A relativistically invariant mass operator

    E-Print Network [OSTI]

    Wilhelm I. Fushchych

    2002-06-10

    In Ukrain. J. Phys., 1967, V.12, N 5, p.741-746 it was shown how, for a given (discrete) mass spectrum of elementary or hypothetical particles, it was possible to construct a non-trivial algebra G containing a Poincare algebra P as a subalgebra so that the mass operator, defined throughout the space where one of the irreducible representations G is given, is self-conjugate and its spectrum coincides with the given mass spectrum. Such an algebra was constructed in explicit form for the nonrelativistic case, i.e., the generators were written for the algebra. However, the problem of how to assign the algebra G constructively and determine an explicit form of the mass operator in the relativistic case has remained unsolved. In the present work we present a solution of this problem, construct continuum analogs of the classical algebras U(N) and Sp(2N), and show that the problem of including the Poincare algebra can be formulated in the language of wave function equations.

  19. Heavy Vehicle Systems

    SciTech Connect (OSTI)

    Sid Diamond; Richard Wares; Jules Routbort

    2000-04-11

    Heavy Vehicle (HV) systems are a necessary component of achieving OHVT goals. Elements are in place for a far-ranging program: short, intermediate, and long-term. Solicitation will bring industrial input and support. Future funding trend is positive, outlook for HV systems is good.

  20. PHYTOEXTRACTION OF HEAVY METALS

    E-Print Network [OSTI]

    Blouin-Demers, Gabriel

    Plants Chelating agents Pb hyperaccumulation Effects of pH on metal extraction Disposal options contaminants from soils Contaminants must be in harvestable portions of the plant (Wongkongkatep et al. 2003) Chelating Agents: desorb heavy metals from soil matrix and form water-soluble metal complexes (Shen et al

  1. Heavy Quark Physics

    E-Print Network [OSTI]

    Paul B. Mackenzie

    1992-12-14

    Lattice calculations of heavy quark systems provide very good measures of the lattice spacing, a key element in recent determinations of the strong coupling constant using lattice methods. They also provide excellent testing grounds for lattice methods in general. I review recent phenomenological and technical developments in this field.

  2. The Upgrade and Performance of the ATLAS Tau Trigger towards Run 2

    E-Print Network [OSTI]

    Karamaoun, Andrew; The ATLAS collaboration

    2015-01-01

    Tau triggers are used in a variety of highly anticipated ATLAS physics analyses, including the measurement of the Higgs boson coupling to fermions and searches for Higgs boson partners or heavy resonances decaying into pairs of tau leptons. As proton-proton collisions at the LHC reach instantaneous luminosities of over 10 34 cm ?2 s ?1 , the strategies for triggering have become more sophisticated than in Run 1. In these conditions single tau lepton triggers suffer from severe rate limitations, despite the advancements in algorithms used in the tau identification. Further fast algorithms and the design of topological selections are the main developments to allow a large program of physics analysis. In Run 2, topological criteria can be applied already at the first trigger level, due to the addition of the L1 topological processor. This makes it possible to use detailed information from sub-detectors in order to apply real-time event topology cuts. The evolution of the ATLAS tau trigger and its performance...

  3. The Upgrade and Performance of the ATLAS Tau Triggers towards Run 2

    E-Print Network [OSTI]

    Karamaoun, Andrew; The ATLAS collaboration

    2015-01-01

    The Upgrade and Performance of the ATLAS Tau Triggers towards Run 2 Tau triggers are used in a variety of highly anticipated ATLAS physics analyses, including the measurement of the Higgs boson coupling to fermions and searches for Higgs boson partners or heavy resonances decaying into pairs of tau leptons. As proton-proton collisions at the LHC reach instantaneous luminosities of over 10^34cm^ -2s-1, the strategies for triggering have become more sophisticated than in Run 1. In these conditions single tau lepton triggers suffer from severe rate limitations, despite the advancements in algorithms used in the tau identification. Further fast algorithms and the design of topological selections are the main developments to allow a large program of physics analysis. In Run 2 topological criteria can be applied already at the first trigger level, due to the addition of the L1 topological processor. This makes it possible to use detailed information from sub-detectors in order to apply real-time event topology cuts...

  4. Triggering events with GPUs at ATLAS

    E-Print Network [OSTI]

    Kama, Sami; The ATLAS collaboration

    2015-01-01

    The growing complexity of events produced in LHC collisions demands more and more computing power both for the online selection and for the offline reconstruction of events. In recent years, the explosive performance growth of massively parallel processors like Graphics Processing Units~(GPU) both in computing power and in low energy consumption, make GPU extremely attractive for using them in a complex high energy experiment like ATLAS. Together with the optimization of reconstruction algorithms this new massively parallel paradigm is exploited. For this purpose a small scale prototype of the full ATLAS High Level Trigger involving GPU has been implemented. We discuss the integration procedure of this prototype, the achieved performance and the prospects for the future

  5. ATLAS Distributed Computing in LHC Run2

    E-Print Network [OSTI]

    Campana, Simone; The ATLAS collaboration

    2015-01-01

    The ATLAS Distributed Computing infrastructure has evolved after the first period of LHC data taking in order to cope with the challenges of the upcoming LHC Run2. An increased data rate and computing demands of the Monte-Carlo simulation, as well as new approaches to ATLAS analysis, dictated a more dynamic workload management system (ProdSys2) and data management system (Rucio), overcoming the boundaries imposed by the design of the old computing model. In particular, the commissioning of new central computing system components was the core part of the migration toward the flexible computing model. The flexible computing utilization exploring the opportunistic resources such as HPC, cloud, and volunteer computing is embedded in the new computing model, the data access mechanisms have been enhanced with the remote access, and the network topology and performance is deeply integrated into the core of the system. Moreover a new data management strategy, based on defined lifetime for each dataset, has been defin...

  6. The ATLAS Data Management Software Engineering Process

    E-Print Network [OSTI]

    Lassnig, M; The ATLAS collaboration; Stewart, G A; Barisits, M; Beermann, T; Vigne, R; Serfon, C; Goossens, L; Nairz, A; Molfetas, A

    2014-01-01

    Rucio is the next-generation data management system of the ATLAS experiment. The software engineering process to develop Rucio is fundamentally different to existing software development approaches in the ATLAS distributed computing community. Based on a conceptual design document, development takes place using peer-reviewed code in a test-driven environment. The main objectives are to ensure that every engineer understands the details of the full project, even components usually not touched by them, that the design and architecture are coherent, that temporary contributors can be productive without delay, that programming mistakes are prevented before being committed to the source code, and that the source is always in a fully functioning state. This contribution will illustrate the workflows and products used, and demonstrate the typical development cycle of a component from inception to deployment within this software engineering process. Next to the technological advantages, this contribution will also hi...

  7. The ATLAS Data Management Software Engineering Process

    E-Print Network [OSTI]

    Lassnig, M; The ATLAS collaboration; Stewart, G A; Barisits, M; Beermann, T; Vigne, R; Serfon, C; Goossens, L; Nairz, A

    2013-01-01

    Rucio is the next-generation data management system of the ATLAS experiment. The software engineering process to develop Rucio is fundamentally different to existing software development approaches in the ATLAS distributed computing community. Based on a conceptual design document, development takes place using peer-reviewed code in a test-driven environment. The main objectives are to ensure that every engineer understands the details of the full project, even components usually not touched by them, that the design and architecture are coherent, that temporary contributors can be productive without delay, that programming mistakes are prevented before being committed to the source code, and that the source is always in a fully functioning state. This contribution will illustrate the workflows and products used, and demonstrate the typical development cycle of a component from inception to deployment within this software engineering process. Next to the technological advantages, this contribution will also hi...

  8. Optimizing the ATLAS code with different profilers

    E-Print Network [OSTI]

    Kama, S; The ATLAS collaboration

    2013-01-01

    After the current maintenance period, the LHC will provide higher energy collisions with increased luminosity. In order to keep up with these higher rates, ATLAS software needs to speed up substantially. However, ATLAS code is composed of approximately 4M lines, written by many different programmers with different backgrounds, which makes code optimisation a challenge. To help with this effort different profiling tools and techniques are being used. These include well known tools, such as the Valgrind suite and Intel Amplifier; less common tools like PIN, PAPI, and GOODA; as well as techniques such as library interposing. In this talk we will mainly focus on PIN tools and GOODA. PIN is a dynamic binary instrumentation tool which can obtain statistics such as call counts, instruction counts and interrogate functions' arguments. It has been used to obtain CLHEP Matrix profiles, operations and vector sizes for linear algebra calculations which has provided the insight necessary to achieve significant performance...

  9. Overview of ATLAS Standard Model Measurements

    E-Print Network [OSTI]

    Buttinger, William; The ATLAS collaboration

    2015-01-01

    The precise measurement of known Standard Model processes is an important part of the ATLAS physics programme. A wide spectrum of final states is covered ranging from the measurement of the total proton-proton cross section down to very rare processes like the production of same-sign W pairs. These measurements serve to constrain phenomenological models of the strong interaction, provide precision tests of perturbative QCD calculations up to the next-to-next-to-leading order, improve our knowledge on the proton structure, measure fundamental Standard Model parameters to high precision or test the Electroweak gauge structure, providing model-independent constraints on new physics. Recent highlights of Run-1 measurements are reported, including new results on multi-differential jet and photon production, precision measurements with single W and Z bosons and multiboson production. The ATLAS Standard model group is also committed to perform several measurements with the data collected in the early Run 2 of the LH...

  10. The ATLAS Data Quality Defect Database System

    E-Print Network [OSTI]

    T. Golling; H. S. Hayward; P. U. E. Onyisi; H. J. Stelzer; P. Waller

    2012-05-14

    The ATLAS experiment at the Large Hadron Collider has implemented a new system for recording information on detector status and data quality, and for transmitting this information to users performing physics analysis. This system revolves around the concept of "defects," which are well-defined, fine-grained, unambiguous occurrences affecting the quality of recorded data. The motivation, implementation, and operation of this system is described.

  11. Review of the ATLAS Forward Measurements

    E-Print Network [OSTI]

    Gach, Grzegorz Pawel; The ATLAS collaboration

    2015-01-01

    A review of ATLAS forward measurements to be presented at Workshop on Forward Physics and High-Energy Scattering at ZERO Degrees in Nagoya. The following analyses are discussed: - Measurement of the Inelastic Proton-Proton Cross Section at 7 and 13 TeV - Rapidity Gap Cross Sections - Measurements of Jet Vetoes and Azimuthal Decorrelations in Dijet Events Produced - Dijet Production in 7 TeV pp Collisions with Large Rapidity Gaps

  12. Recent Higgs results from the ATLAS experiment

    SciTech Connect (OSTI)

    Brendlinger, Kurt; Collaboration: ATLAS Collaboration

    2014-06-24

    This paper presents recent results on the Higgs boson from the ATLAS experiment at the Large Hadron Collider. The Collaboration reports on measurements of the signal strength, couplings, and spin of the Higgs in several decay channels. We find all measurements to be consistent with Standard Model predictions. The Higgs branching fraction to invisible particles is constrained and no evidence of physics beyond the Standard Model is found.

  13. Optical Link of the Atlas Pixel Detector

    E-Print Network [OSTI]

    K. K. Gan

    2007-12-06

    The on-detector optical link of the ATLAS pixel detector contains radiation-hard receiver chips to decode bi-phase marked signals received on PIN arrays and data transmitter chips to drive VCSEL arrays. The components are mounted on hybrid boards (opto-boards). We present results from the irradiation studies with 24 GeV protons up to 32 Mrad (1.2 x 10^15 p/cm^2) and the experience from the production.

  14. Template:AtlasTabs | Open Energy Information

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page| Open Energy Information Serbia-EnhancingEt Al., 2013) | Open Energy InformationEnergyAtlasTabs Jump to:

  15. TOWARDS A NATIONAL ATLAS -GEO WEB SERVICE Bormy Chanthong (Royal University of Phnom Penh)

    E-Print Network [OSTI]

    Köbben, Barend

    TOWARDS A NATIONAL ATLAS - GEO WEB SERVICE Bormy Chanthong (Royal University of Phnom Penh) Drs. B is to formulate and design a conceptual model of the National Atlas - Geo Web service. The National Atlas - Geo Web service is designed as a loosely coupled system. As an interoperable node, the National Atlas

  16. RisR1252(EN) The Numerical Wind Atlas

    E-Print Network [OSTI]

    Risø­R­1252(EN) The Numerical Wind Atlas -- the KAMM/WAsP Method Helmut P. Frank, Ole Rathmann The method of combining the Karlsruhe Atmospheric Mesoscale Model, KAMM, with the Wind Atlas Analysis and Application Program, WAsP, to make local predictions of the wind resource is presented. It combines

  17. Quo Vadis, Atlas-Based Segmentation? Torsten Rohlfing1

    E-Print Network [OSTI]

    Menzel, Randolf - Institut für Biologie

    ¨at Berlin, Berlin, Germany 4 Department of Neurosurgery and Computer Science Department, Stanford University in J. Suri, D. L. Wilson, and S. Laxminarayan (eds.), The Handbook of Medical Image Analysis to Atlas: Image Acquisition and Processing . . . . . . . 3 11.3 Fundamentals of Atlas-Based Segmentation

  18. General relativistic observables of the GRAIL mission

    E-Print Network [OSTI]

    Turyshev, Slava G; Sazhin, Mikhail V

    2012-01-01

    We present a realization of astronomical relativistic reference frames in the solar system and its application to the GRAIL mission. We model the necessary spacetime coordinate transformations for light-trip time computations and address some practical aspects of the implementation of the resulting model. We develop all the relevant relativistic coordinate transformations that are needed to describe the motion of the GRAIL spacecraft and to compute all observable quantities. We take into account major relativistic effects contributing to the dual one-way range observable, which is derived from one-way signal travel times between the two GRAIL spacecraft. We develop a general relativistic model for this fundamental observable of GRAIL, accurate to 1 $\\mu$m. We develop and present a relativistic model for another key observable of this experiment, the dual one-way range-rate, accurate to 1 $\\mu$m/s. The presented formulation justifies the basic assumptions behind the design of the GRAIL mission. It may also be ...

  19. General relativistic observables of the GRAIL mission

    E-Print Network [OSTI]

    Slava G. Turyshev; Viktor T. Toth; Mikhail V. Sazhin

    2012-12-18

    We present a realization of astronomical relativistic reference frames in the solar system and its application to the GRAIL mission. We model the necessary spacetime coordinate transformations for light-trip time computations and address some practical aspects of the implementation of the resulting model. We develop all the relevant relativistic coordinate transformations that are needed to describe the motion of the GRAIL spacecraft and to compute all observable quantities. We take into account major relativistic effects contributing to the dual one-way range observable, which is derived from one-way signal travel times between the two GRAIL spacecraft. We develop a general relativistic model for this fundamental observable of GRAIL, accurate to 1 $\\mu$m. We develop and present a relativistic model for another key observable of this experiment, the dual one-way range-rate, accurate to 1 $\\mu$m/s. The presented formulation justifies the basic assumptions behind the design of the GRAIL mission. It may also be used to further improve the already impressive results of this lunar gravity recovery experiment after the mission is complete. Finally, we present transformation rules for frequencies and gravitational potentials and their application to GRAIL.

  20. Heavy Vehicle Propulsion Materials

    SciTech Connect (OSTI)

    Ray Johnson

    2000-01-31

    The objectives are to Provide Key Enabling Materials Technologies to Increase Energy Efficiency and Reduce Exhaust Emissions. The following goals are listed: Goal 1: By 3rd quarter 2002, complete development of materials enabling the maintenance or improvement of fuel efficiency {ge} 45% of class 7-8 truck engines while meeting the EPA/Justice Department ''Consent Decree'' for emissions reduction. Goal 2: By 4th quarter 2004, complete development of enabling materials for light-duty (class 1-2) diesel truck engines with efficiency over 40%, over a wide range of loads and speeds, while meeting EPA Tier 2 emission regulations. Goal 3: By 4th quarter 2006, complete development of materials solutions to enable heavy-duty diesel engine efficiency of 50% while meeting the emission reduction goals identified in the EPA proposed rule for heavy-duty highway engines.''

  1. Viscous heavy brines

    SciTech Connect (OSTI)

    House, R.F.; Hoover, L.D.

    1984-07-10

    Hydroxyethyl cellulose and a sequestrant are added to a heavy brine containing one or more salts selected from calcium chloride, calcium bromide, and zinc bromide to increase the viscosity of the brine. Preferably the brine contains zinc bromide, has a density in the range from about 14.2-19.2 pounds per gallon, and the sequestrant is a polyphosphonic acid or water soluble salt thereof.

  2. Utah Heavy Oil Program

    SciTech Connect (OSTI)

    J. Bauman; S. Burian; M. Deo; E. Eddings; R. Gani; R. Goel; C.K. Huang; M. Hogue; R. Keiter; L. Li; J. Ruple; T. Ring; P. Rose; M. Skliar; P.J. Smith; J.P. Spinti; P. Tiwari; J. Wilkey; K. Uchitel

    2009-10-20

    The Utah Heavy Oil Program (UHOP) was established in June 2006 to provide multidisciplinary research support to federal and state constituents for addressing the wide-ranging issues surrounding the creation of an industry for unconventional oil production in the United States. Additionally, UHOP was to serve as an on-going source of unbiased information to the nation surrounding technical, economic, legal and environmental aspects of developing heavy oil, oil sands, and oil shale resources. UHOP fulGilled its role by completing three tasks. First, in response to the Energy Policy Act of 2005 Section 369(p), UHOP published an update report to the 1987 technical and economic assessment of domestic heavy oil resources that was prepared by the Interstate Oil and Gas Compact Commission. The UHOP report, entitled 'A Technical, Economic, and Legal Assessment of North American Heavy Oil, Oil Sands, and Oil Shale Resources' was published in electronic and hard copy form in October 2007. Second, UHOP developed of a comprehensive, publicly accessible online repository of unconventional oil resources in North America based on the DSpace software platform. An interactive map was also developed as a source of geospatial information and as a means to interact with the repository from a geospatial setting. All documents uploaded to the repository are fully searchable by author, title, and keywords. Third, UHOP sponsored Give research projects related to unconventional fuels development. Two projects looked at issues associated with oil shale production, including oil shale pyrolysis kinetics, resource heterogeneity, and reservoir simulation. One project evaluated in situ production from Utah oil sands. Another project focused on water availability and produced water treatments. The last project considered commercial oil shale leasing from a policy, environmental, and economic perspective.

  3. Non-relativistic high-energy physics: top production and dark matter annihilation

    E-Print Network [OSTI]

    Beneke, Martin

    2015-01-01

    Non-relativistic physics is often associated with atomic physics and low-energy phenomena of the strong interactions between nuclei and quarks. In this review we cover three topics in contemporary high-energy physics at or close to the TeV scale, where non-relativistic dynamics plays an important if not defining role. We first discuss in detail the third-order corrections to top-quark pair production in electron-positron collisions in the threshold region, which plays a major role at a future high-energy e+ e- collider. Threshold effects are also relevant in the production of heavy particles in hadronic collisions, where in addition to the Coulomb force soft gluon radiation contributes to enhanced quantum corrections. We review the joint resummation of non-relativistic and soft gluon effects for pair production of top quarks and supersymmetric particles to next-to-next-to-leading logarithmic accuracy. The third topic deals with pair annihilation of dark matter particles within the framework of the Minimal Sup...

  4. Non-relativistic high-energy physics: top production and dark matter annihilation

    E-Print Network [OSTI]

    Martin Beneke; Matthias Steinhauser

    2015-06-26

    Non-relativistic physics is often associated with atomic physics and low-energy phenomena of the strong interactions between nuclei and quarks. In this review we cover three topics in contemporary high-energy physics at or close to the TeV scale, where non-relativistic dynamics plays an important if not defining role. We first discuss in detail the third-order corrections to top-quark pair production in electron-positron collisions in the threshold region, which plays a major role at a future high-energy e+ e- collider. Threshold effects are also relevant in the production of heavy particles in hadronic collisions, where in addition to the Coulomb force soft gluon radiation contributes to enhanced quantum corrections. We review the joint resummation of non-relativistic and soft gluon effects for pair production of top quarks and supersymmetric particles to next-to-next-to-leading logarithmic accuracy. The third topic deals with pair annihilation of dark matter particles within the framework of the Minimal Supersymmetric Standard Model. Here the electroweak Yukawa force generated by the exchange of gauge and Higgs bosons can cause large "Sommerfeld" enhancements of the annihilation cross section in some parameter regions.

  5. Interpolating relativistic and non-relativistic Nambu-Goldstone and Higgs modes

    E-Print Network [OSTI]

    Michikazu Kobayashi; Muneto Nitta

    2015-05-19

    When a continuous symmetry is spontaneously broken in non-relativistic theories, there appear Nambu-Goldstone (NG) modes, whose dispersion relations are either linear (type-I) or quadratic (type-II). We give a general framework to interpolate between relativistic and non-relativistic NG modes, revealing a nature of type-I and II NG modes in non-relativistic theories. The interpolating Lagrangians have the nonlinear Lorentz invariance which reduces to the Galilei or Schrodinger invariance in the non-relativistic limit. We find that type-I and type-II NG modes in the interpolating region are accompanied with a Higgs mode and a chiral NG partner, respectively, both of which are gapful. In the ultra-relativistic limit, a set of a type-I NG mode and its Higgs partner remains, while a set of type-II NG mode and gapful NG partner turns to a set of two type-I NG modes. In the non-relativistic limit, the both types of accompanied gapful modes become infinitely massive, disappearing from the spectrum. The examples contain a phonon in Bose-Einstein condensates, a magnon in ferromagnets, and a Kelvon and dilaton-magnon localized around a skyrmion line in ferromagnets.

  6. Relativistic electron acceleration by oblique whistler waves

    SciTech Connect (OSTI)

    Yoon, Peter H.; School of Space Research, Kyung Hee University, Yongin-Si, Gyeonggi-Do 446-701 ; Pandey, Vinay S.; Lee, Dong-Hun

    2013-11-15

    Test-particle simulations of electrons interacting with finite-amplitude, obliquely propagating whistler waves are carried out in order to investigate the acceleration of relativistic electrons by these waves. According to the present findings, an efficient acceleration of relativistic electrons requires a narrow range of oblique propagation angles, close to the whistler resonance cone angle, when the wave amplitude is held constant at relatively low value. For a constant wave propagation angle, it is found that a range of oblique whistler wave amplitudes permits the acceleration of relativistic electrons to O(MeV) energies. An initial distribution of test electrons is shown to form a power-law distribution when plotted in energy space. It is also found that the acceleration is largely uniform in electron pitch-angle space.

  7. Assessment of the MUSTA approach for numerical relativistic dynamics

    E-Print Network [OSTI]

    Blakely, P. M.; Nikiforakis, N.; Henshaw, W. D.

    2015-03-04

    waves 1. Introduction The numerical solution of the relativistic hydrodynamical equa- tions is of importance to the simulation of astrophysical phe- nomena such as gamma-ray bursts, supernova core-collapse, and relativistic wind accretion. Although...

  8. Quarkonium and hydrogen spectra with spin dependent relativistic wave equation

    E-Print Network [OSTI]

    Vikram H. Zaveri

    2014-11-25

    A non-linear non-perturbative relativistic atomic theory introduces spin in the dynamics of particle motion. The resulting energy levels of Hydrogen atom are exactly same as the Dirac theory. The theory accounts for the energy due to spin-orbit interaction and for the additional potential energy due to spin and spin-orbit coupling. Spin angular momentum operator is integrated into the equation of motion. This requires modification to classical Laplacian operator. Consequently the Dirac matrices and the k operator of Dirac's theory are dispensed with. The theory points out that the curvature of the orbit draws on certain amount of kinetic and potential energies affecting the momentum of electron and the spin-orbit interaction energy constitutes a part of this energy. The theory is developed for spin 1/2 bound state single electron in Coulomb potential and then further extended to quarkonium physics by introducing the linear confining potential. The unique feature of this quarkonium model is that the radial distance can be exactly determined and does not have a statistical interpretation. The established radial distance is then used to determine the wave function. The observed energy levels are used as the input parameters and the radial distance and the string tension are predicted. This ensures 100% conformance to all observed energy levels for the heavy quarkonium.

  9. Relativistic Wave Equations: An Operational Approach

    E-Print Network [OSTI]

    G. Dattoli; E. Sabia; K. Górska; A. Horzela; K. A. Penson

    2015-02-02

    The use of operator methods of algebraic nature is shown to be a very powerful tool to deal with different forms of relativistic wave equations. The methods provide either exact or approximate solutions for various forms of differential equations, such as relativistic Schr\\"odinger, Klein-Gordon and Dirac. We discuss the free particle hypotheses and those relevant to particles subject to non-trivial potentials. In the latter case we will show how the proposed method leads to easily implementable numerical algorithms.

  10. General relativistic tidal heating for Moller pseudotensor

    E-Print Network [OSTI]

    Lau Loi So

    2015-09-30

    Thorne elucidated that the relativistic tidal heating is the same as the Newtonian theory. Moreover, Thorne also claimed that the tidal heating is independent of how one localizes gravitational energy and is unambiguously given by a certain formula. Purdue and Favata calculated the tidal heating for different classical pseudotensors including Moller and obtained the results all matched with the Newtonian perspective. After re-examined this Moller pseudotensor, we find that there does not exist any tidal heating value. Thus we claim that the relativistic tidal heating is pseudotensor independent under the condition that if the peusdotensor is a Freud typed superpotential.

  11. General relativistic tidal heating for Moller pseudotensor

    E-Print Network [OSTI]

    So, Lau Loi

    2015-01-01

    Thorne elucidated that the relativistic tidal heating is the same as the Newtonian theory. Moreover, Thorne also claimed that the tidal heating is independent of how one localizes gravitational energy and is unambiguously given by a certain formula. Purdue and Favata calculated the tidal heating for different classical pseudotensors including Moller and obtained the results all matched with the Newtonian perspective. After re-examined this Moller pseudotensor, we find that there does not exist any tidal heating value. Thus we claim that the relativistic tidal heating is pseudotensor independent under the condition that if the peusdotensor is a Freud typed superpotential.

  12. Variational generalization of free relativistic top

    E-Print Network [OSTI]

    Roman Matsyuk

    2014-07-25

    We prove that well known first-order (in spin, momentum, and space-time coordinates) equations of motion of relativistic top are equivalent to the third-order equations of Mathisson on the surface of the Mathisson-Pirani auxiliary constraint. We then consider these third-order equations in flat space-time with constant spin 4-vector and invent a Lagrange function for them. Allowing physical interpretation to be applied to the complete set of extremals yields a whole spectrum of spin-dependent effective 'proper mass' of the relativistic top.

  13. Heavy-Duty Low-Temperature and Diesel Combustion & Heavy-Duty...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    More Documents & Publications Heavy-Duty Low-Temperature and Diesel Combustion & Heavy-Duty Combustion Modeling Heavy-Duty Low-Temperature and Diesel Combustion &...

  14. The compatibility of LHC Run 1 data with a heavy scalar of mass around 270\\,GeV

    E-Print Network [OSTI]

    Stefan von Buddenbrock; Nabarun Chakrabarty; Alan S. Cornell; Deepak Kar; Mukesh Kumar; Tanumoy Mandal; Bruce Mellado; Biswarup Mukhopadhyaya; Robert G. Reed

    2015-11-15

    The first run of the LHC was successful in that it saw the discovery of the elusive Higgs boson, a particle that is consistent with the SM hypothesis. There are a number of excesses in Run 1 ATLAS and CMS results which can be interpreted as being due to the existence of another heavier scalar particle. This particle has decay modes which we have studied using LHC Run 1 data. Using a minimalistic model, we can predict the kinematics of these final states and compare the prediction against data directly. A statistical combination of these results shows that a best fit point is found for a heavy scalar having a mass of 272$^{+12}_{-9}$\\,GeV. This result has been quantified as a three sigma effect, based on analyses which are not necessarily optimized for the search of a heavy scalar. The smoking guns for the discovery of this new heavy scalar and the prospects for Run 2 are discussed.

  15. Black Sun: Ocular Invisibility of Relativistic Luminous Astrophysical Bodies

    E-Print Network [OSTI]

    Jeffrey S. Lee; Gerald B. Cleaver

    2015-08-16

    The relativistic Doppler shifting of visible electromagnetic radiation to beyond the human ocular range reduces the incident radiance of the source. Consequently, luminous astrophysical bodies (LABs) can be rendered invisible with sufficient relativistic motion. This paper determines the proper distance as a function of relativistic velocity at which a luminous object attains ocular invisibility.

  16. ATLAS Run-2 status and performance

    E-Print Network [OSTI]

    Pastore, Francesca; The ATLAS collaboration

    2015-01-01

    During the 2013/2014 shutdown of the LHC the ATLAS detector has been improved. A new silicon pixel detector layer has been installed, and the muon detector coverage has been improved substantially. In addition nearly all other parts of the detector have also been revised to adapt them to the higher pileup conditions or make them more robust in general. This talk will describe these improvements, and how they affect the performance of physics objects. The initial results showing the detector performance as obtained from cosmic runs and/or initial beam data will also be shown.

  17. Astrophysics experiments with radioactive beams at ATLAS

    SciTech Connect (OSTI)

    Back, B. B.; Clark, J. A.; Pardo, R. C.; Rehm, K. E., E-mail: rehm@anl.gov; Savard, G. [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)] [Physics Division, Argonne National Laboratory, Argonne, IL 60439 (United States)

    2014-04-15

    Reactions involving short-lived nuclei play an important role in nuclear astrophysics, especially in explosive scenarios which occur in novae, supernovae or X-ray bursts. This article describes the nuclear astrophysics program with radioactive ion beams at the ATLAS accelerator at Argonne National Laboratory. The CARIBU facility as well as recent improvements for the in-flight technique are discussed. New detectors which are important for studies of the rapid proton or the rapid neutron-capture processes are described. At the end we briefly mention plans for future upgrades to enhance the intensity, purity and the range of in-flight and CARIBU beams.

  18. ATLAS measurements of multi-boson production

    E-Print Network [OSTI]

    Christopher Hays; for the ATLAS Collaboration

    2014-10-17

    Measurements of electroweak gauge-boson pair-production in sqrt(s) = 7 and 8 TeV pp collisions at the LHC probe self-couplings and interference effects to an accuracy of O(10%) or better. ATLAS measurements of ZZ and WZ production at both center of mass energies, and of WW, Zgamma and Wgamma production at sqrt(s) = 7 TeV, are presented. Total, fiducial, and differential cross sections are given, along with limits on anomalous triple-gauge couplings.

  19. ATLAS upgrade June09_v3

    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 OutreachProductswsicloudwsicloudden Documentation DataStreamsTotalproposals duenationalMeeting - June 4-5,ATLAS

  20. Global Atlas | OpenEI Community

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar2-0057-EA Jump to:ofEniaElectric JumpAtlas for Solar and Wind Energy Jump

  1. Heavy Truck Engine Program

    SciTech Connect (OSTI)

    Nelson, Christopher

    2009-01-08

    The Heavy Duty Truck Engine Program at Cummins embodied three significant development phases. All phases of work strove to demonstrate a high level of diesel engine efficiency in the face of increasingly stringent emission requirements. Concurrently, aftertreatment system development and refinement was pursued in support of these efficiency demonstrations. The program's first phase focused on the demonstration in-vehicle of a high level of heavy duty diesel engine efficiency (45% Brake Thermal Efficiency) at a typical cruise condition while achieving composite emissions results which met the 2004 U.S. EPA legislated standards. With a combination of engine combustion calibration tuning and the development and application of Urea-based SCR and particulate aftertreatment, these demonstrations were successfully performed by Q4 of 2002. The second phase of the program directed efforts towards an in-vehicle demonstration of an engine system capable of meeting 2007 U.S. EPA legislated emissions requirements while achieving 45% Brake Thermal Efficiency at cruise conditions. Through further combustion optimization, the refinement of Cummins Cooled EGR architecture, the application of a high pressure common rail fuel system and the incorporation of optimized engine parasitics, Cummins Inc. successfully demonstrated these deliverables in Q2 of 2004. The program's final phase set a stretch goal of demonstrating 50% Brake Thermal Efficiency from a heavy duty diesel engine system capable of meeting 2010 U.S. EPA legislated emissions requirements. Cummins chose to pursue this goal through further combustion development and refinement of the Cooled EGR system architecture and also applied a Rankine cycle Waste Heat Recovery technique to convert otherwise wasted thermal energy to useful power. The engine and heat recovery system was demonstrated to achieve 50% Brake Thermal Efficiency while operating at a torque peak condition in second quarter, 2006. The 50% efficient engine system was capable of meeting 2010 emissions requirements through the application of NOx and particulate matter reduction techniques proven earlier in the program.

  2. Heavy Quarkonium Physics

    E-Print Network [OSTI]

    N. Brambilla; M. Krämer; R. Mussa; A. Vairo; G. Bali; G. T. Bodwin; E. Braaten; E. Eichten; S. Eidelman; S. Godfrey; A. Hoang; M. Jamin; D. Kharzeev; M. P. Lombardo; C. Lourenco; A. B. Meyer; V. Papadimitriou; C. Patrignani; M. Rosati; M. A. Sanchis-Lozano; H. Satz; J. Soto; D. Z. Besson; D. Bettoni; A. Böhrer; S. Boogert; C. -H. Chang; P. Cooper; P. Crochet; S. Datta; C. Davies; A. Deandrea; R. Faustov; T. Ferguson; R. Galik; F. A. Harris; O. Iouchtchenko; O. Kaczmarek; F. Karsch; M. Kienzle; V. V. Kiselev; S. R. Klein; P. Kroll; A. Kronfeld; Y. -P. Kuang; V. Laporta; Jungil Lee; A. Leibovich; J. P. Ma; P. Mackenzie; L. Maiani; M. L. Mangano; A. Meyer; X. H. Mo; C. Morningstar; A. Nairz; J. Napolitano; S. Olsen; A. Penin; P. Petreczky; F. Piccinini; A. Pineda; A. D. Polosa; L. Ramello; R. Rapp; J. -M. Richard; V. Riquer; S. Ricciardi; E. Robutti; O. Schneider; E. Scomparin; J. Simone; T. Skwarnicki; G. Stancari; I. W. Stewart; Yu. Sumino; T. Teubner; J. Tseng; R. Vogt; P. Wang; B. Yabsley; C. Z. Yuan; F. Zantow; Z. G. Zhao; A. Zieminski

    2005-07-26

    This report is the result of the collaboration and research effort of the Quarkonium Working Group over the last three years. It provides a comprehensive overview of the state of the art in heavy-quarkonium theory and experiment, covering quarkonium spectroscopy, decay, and production, the determination of QCD parameters from quarkonium observables, quarkonia in media, and the effects on quarkonia of physics beyond the Standard Model. An introduction to common theoretical and experimental tools is included. Future opportunities for research in quarkonium physics are also discussed.

  3. Light is Heavy

    E-Print Network [OSTI]

    van der Mark, M B

    2015-01-01

    Einstein's relativity theory appears to be very accurate, but at times equally puzzling. On the one hand, electromagnetic radiation must have zero rest mass in order to propagate at the speed of light, but on the other hand, since it definitely carries momentum and energy, it has non-zero inertial mass. Hence, by the principle of equivalence, it must have non-zero gravitational mass, and so, light must be heavy. In this paper, no new results will be derived, but a possibly surprising perspective on the above paradox is given.

  4. Sandia Energy - Heavy Duty

    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)Geothermal Energy & Drilling TechnologyHeavy Duty Home Transportation

  5. Relativistic magnetotransport in graphene Markus Mller

    E-Print Network [OSTI]

    Müller, Markus

    the thermal and electric transport of a fluid of interacting Dirac fermions as they arise in single: Graphene, relativistic fluids, magnetohydrodynamics, magnetotransport, Boltzmann equation PACS: 73.63.Db in the critical regime µ/T 1 of a clean system [5, 7]. A logarithmic divergence in the collinear scattering

  6. INL '@work' heavy equipment mechanic

    SciTech Connect (OSTI)

    Christensen, Cad

    2008-01-01

    INL's Cad Christensen is a heavy equipment mechanic. For more information about INL careers, visit http://www.facebook.com/idahonationallaboratory.

  7. INL '@work' heavy equipment mechanic

    ScienceCinema (OSTI)

    Christensen, Cad

    2013-05-28

    INL's Cad Christensen is a heavy equipment mechanic. For more information about INL careers, visit http://www.facebook.com/idahonationallaboratory.

  8. The European Solar Radiation Atlas 1 Page J., M. Albuisson, L. Wald, 2001. The European solar radiation atlas: a valuable digital tool. Solar Energy,

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    : solar water heaters, passive solar buildings, photovoltaic cells and biomass production. In each caseThe European Solar Radiation Atlas 1 Page J., M. Albuisson, L. Wald, 2001. The European solar radiation atlas: a valuable digital tool. Solar Energy, 71, 81-83, 2001.1 The European Solar Radiation Atlas

  9. The ATLAS Experiment: Getting Ready for the LHC

    SciTech Connect (OSTI)

    Jenni, Peter (CERN) [CERN

    2006-05-15

    At CERN the Large Hadron Collider (LHC) project is well advanced. First proton-proton collisions at the high-energy frontier are expected for the second half of 2007. In parallel to the collider construction the powerful general-purpose ATLAS detector is being assembled in its underground cavern by a world-wide collaboration. ATLAS will explore new domains of particle physics. After briefly overviewing the LHC construction and installation progress, the status of the ATLAS experiment will be presented, including examples of the exciting prospects for new physics.

  10. Creation and Testing of the ACES Heavy Heavy-Duty Diesel Engine...

    Office of Energy Efficiency and Renewable Energy (EERE) Indexed Site

    Creation and Testing of the ACES Heavy Heavy-Duty Diesel Engine Test Schedule for Representative Measurement of Heavy-Duty Engine Emissions Creation and Testing of the ACES Heavy...

  11. Nonlinear magnetosonic waves in dense plasmas with non-relativistic and ultra-relativistic degenerate electrons

    SciTech Connect (OSTI)

    Hussain, S.; Mahmood, S.; Rehman, Aman-ur-

    2014-11-15

    Linear and nonlinear propagation of magnetosonic waves in the perpendicular direction to the ambient magnetic field is studied in dense plasmas for non-relativistic and ultra-relativistic degenerate electrons pressure. The sources of nonlinearities are the divergence of the ions and electrons fluxes, Lorentz forces on ions and electrons fluids and the plasma current density in the system. The Korteweg-de Vries equation for magnetosonic waves propagating in the perpendicular direction of the magnetic field is derived by employing reductive perturbation method for non-relativistic as well as ultra-relativistic degenerate electrons pressure cases in dense plasmas. The plots of the magnetosonic wave solitons are also shown using numerical values of the plasma parameters such a plasma density and magnetic field intensity of the white dwarfs from literature. The dependence of plasma density and magnetic field intensity on the magnetosonic wave propagation is also pointed out in dense plasmas for both non-relativistic and ultra-relativistic degenerate electrons pressure cases.

  12. Motion of the plasma critical layer during relativistic-electron laser interaction with immobile and comoving ion plasma for ion acceleration

    SciTech Connect (OSTI)

    Sahai, Aakash A., E-mail: aakash.sahai@gmail.com [Department of Electrical Engineering, Duke University, Durham, North Carolina 27708 (United States)

    2014-05-15

    We analyze the motion of the plasma critical layer by two different processes in the relativistic-electron laser-plasma interaction regime (a{sub 0}>1). The differences are highlighted when the critical layer ions are stationary in contrast to when they move with it. Controlling the speed of the plasma critical layer in this regime is essential for creating low-? traveling acceleration structures of sufficient laser-excited potential for laser ion accelerators. In Relativistically Induced Transparency Acceleration (RITA) scheme, the heavy plasma-ions are fixed and only trace-density light-ions are accelerated. The relativistic critical layer and the acceleration structure move longitudinally forward by laser inducing transparency through apparent relativistic increase in electron mass. In the Radiation Pressure Acceleration (RPA) scheme, the whole plasma is longitudinally pushed forward under the action of the laser radiation pressure, possible only when plasma ions co-propagate with the laser front. In RPA, the acceleration structure velocity critically depends upon plasma-ion mass in addition to the laser intensity and plasma density. In RITA, mass of the heavy immobile plasma-ions does not affect the speed of the critical layer. Inertia of the bared immobile ions in RITA excites the charge separation potential, whereas RPA is not possible when ions are stationary.

  13. Crystallization and collapse in relativistically degenerate matter

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M.

    2013-04-15

    In this paper, it is shown that a mass density limit exists beyond which the relativistically degenerate matter would crystallize. The mass density limit, found here, is quite analogous to the mass limit predicted by Chandrasekhar for a type of compact stars called white dwarfs (M{sub Ch} Asymptotically-Equal-To 1.43 Solar Mass). In this study, the old problem of white dwarf core collapse, which has been previously investigated by Chandrasekhar using hydrostatic stability criteria, is revisited in the framework of the quantum hydrodynamics model by inspection of the charge screening at atomic scales in the relativistic degeneracy plasma regime taking into account the relativistic Fermi-Dirac statistics and electron interaction features such as the quantum statistical pressure, Coulomb attraction, electron exchange-correlation, and quantum recoil effects. It is revealed that the existence of ion correlation and crystallization of matter in the relativistically degenerate plasma puts a critical mass density limit on white dwarf core region. It is shown that a white dwarf star with a core mass density beyond this critical limit can undergo the spontaneous core collapse (SCC). The SCC phenomenon, which is dominantly caused by the electron quantum recoil effect (interference and localization of the electron wave function), leads to a new exotic state of matter. In such exotic state, the relativistic electron degeneracy can lead the white dwarf crystallized core to undergo the nuclear fusion and an ultimate supernova by means of the volume reduction (due to the enhanced compressibility) and huge energy release (due to the increase in cohesive energy), under the stars huge inward gravitational pressure. Moreover, it is found that the SCC phenomenon is significantly affected by the core composition (it is more probable for heavier plasmas). The critical mass density found here is consistent with the values calculated for core density of typical white dwarf stars.

  14. Search for a new resonance decaying to a W or Z boson and a Higgs boson in the ??/??/?? + bb¯ final states with the ATLAS detector

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

    Aad, G.

    2015-06-16

    A search for a new resonance decaying to a W or Z boson and a Higgs boson in the ??/??/??+bb¯ final states is performed using 20.3 fb-1 of pp collision data recorded at ?s = 8 TeV with the ATLAS detector at the Large Hadron Collider. The search is conducted by examining the WH / ZH invariant mass distribution for a localized excess. Thus, no significant deviation from the Standard Model background prediction is observed. The results are interpreted in terms of constraints on the Minimal Walking Technicolor model and on a simplified approach based on a phenomenological Lagrangian ofmore »Heavy Vector Triplets.« less

  15. Search for High-Mass States with One Lepton Plus Missing Transverse Momentum in Proton-Proton Collisions at $\\sqrt{s} with the ATLAS Detector

    SciTech Connect (OSTI)

    Aad, Georges; Abbott, Brad; Abdallah, Jalal; Abdelalim, Ahmed Ali; Abdesselam, Abdelouahab; Abdinov, Ovsat; Abi, Babak; Abolins, Maris; Abramowicz, Halina; Abreu, Henso; Acerbi, Emilio; Acharya, Bobby Samir; Adams, David; Addy, Tetteh; Adelman, Jahred; Aderholz, Michael; Adomeit, Stefanie; Adragna, Paolo; Adye, Tim; Aefsky, Scott; Aguilar-Saavedra, Juan Antonio; /Freiburg U. /Oklahoma U. /Barcelona, IFAE /Geneva U. /Oxford U. /Baku, Inst. Phys. /Oklahoma State U. /Michigan State U. /Tel Aviv U. /Orsay, LAL /INFN, Milan /Milan U. /INFN, Udine /ICTP, Trieste /Brookhaven /Hampton U. /Yale U. /Heidelberg, Max Planck Inst. /Munich U. /Queen Mary, U. of London /Rutherford

    2012-06-20

    The ATLAS detector is used to search for high-mass states, such as heavy charged gauge bosons (W{prime},W*), decaying to a charged lepton (electron or muon) and a neutrino. Results are presented based on the analysis of ppcollisions at a center-of-mass energy of 7 TeV corresponding to an integrated luminosity of 36 pb{sup -1}. No excess beyond standard model expectations is observed. A W{prime} with sequential standard model couplings is excluded at 95% confidence level for masses below 1.49 TeV, and a W* (charged chiral boson) for masses below 1.35 TeV.

  16. AINUR: Atlas of Images of NUclear Rings

    E-Print Network [OSTI]

    Comeron, S; Beckman, J E; Laurikainen, E; Salo, H; Martinez-Valpuesta, I; Buta, R J

    2009-01-01

    We present the most complete atlas of nuclear rings to date. We include 109 rings found in 103 galaxies, six of which are elliptical galaxies, five are highly inclined disc galaxies, 17 are unbarred disc galaxies, and 75 are barred disc galaxies. Star-forming nuclear rings occur in 19% of disc galaxies. We aim to explore possible relationships between the size and morphology of the rings and various galactic parameters. We produce colour index and structure maps, as well as Halpha and Paalpha continuum-subtracted images from HST archival data. We derive ellipticity profiles from H-band 2MASS images in order to detect bars and find their metric parameters. We measure the non-axisymmetric torque parameter, Qg, and search for correlations between bar, ring metric parameters, and Qg. Our atlas of nuclear rings includes star-forming and dust rings. Nuclear rings span a range from a few tens of parsecs to a few kiloparsecs in radius. Star-forming nuclear rings can be found in a wide range of morphological types, fr...

  17. optical links for the atlas pixel detector

    E-Print Network [OSTI]

    Stucci, Stefania Antonia; The ATLAS collaboration

    2015-01-01

    Optical links are necessary to satisfy the high speed readout over long distances for advanced silicon detector systems. We report on the optical readout used in the newly installed central pixel layer (IBL) in the ATLAS experiment. The off detector readout employs commercial optical to analog converters, which were extensively tested for this application. Performance measurements during installation and commissioning will be shown. With the increasing instantaneous luminosity in the next years, the next layers outwards of IBL of the ATLAS Pixel detector (Layer 1 and Layer 2) will reach their bandwidth limits. A plan to increase the bandwidth by upgrading the off detector readout chain is put in place. The plan also involves new optical readout components, in particular the optical receivers, for which commercial units cannot be used and a new design has been made. The latter allows for a wider operational range in term of data frequency and light input power to match the on-detector sending units on the pres...

  18. A NEW MULTI-DIMENSIONAL GENERAL RELATIVISTIC NEUTRINO HYDRODYNAMICS CODE FOR CORE-COLLAPSE SUPERNOVAE. II. RELATIVISTIC EXPLOSION MODELS OF CORE-COLLAPSE SUPERNOVAE

    SciTech Connect (OSTI)

    Mueller, Bernhard; Janka, Hans-Thomas; Marek, Andreas, E-mail: bjmuellr@mpa-garching.mpg.de, E-mail: thj@mpa-garching.mpg.de [Max-Planck-Institut fuer Astrophysik, Karl-Schwarzschild-Str. 1, D-85748 Garching (Germany)

    2012-09-01

    We present the first two-dimensional general relativistic (GR) simulations of stellar core collapse and explosion with the COCONUT hydrodynamics code in combination with the VERTEX solver for energy-dependent, three-flavor neutrino transport, using the extended conformal flatness condition for approximating the space-time metric and a ray-by-ray-plus ansatz to tackle the multi-dimensionality of the transport. For both of the investigated 11.2 and 15 M{sub Sun} progenitors we obtain successful, though seemingly marginal, neutrino-driven supernova explosions. This outcome and the time evolution of the models basically agree with results previously obtained with the PROMETHEUS hydro solver including an approximative treatment of relativistic effects by a modified Newtonian potential. However, GR models exhibit subtle differences in the neutrinospheric conditions compared with Newtonian and pseudo-Newtonian simulations. These differences lead to significantly higher luminosities and mean energies of the radiated electron neutrinos and antineutrinos and therefore to larger energy-deposition rates and heating efficiencies in the gain layer with favorable consequences for strong nonradial mass motions and ultimately for an explosion. Moreover, energy transfer to the stellar medium around the neutrinospheres through nucleon recoil in scattering reactions of heavy-lepton neutrinos also enhances the mentioned effects. Together with previous pseudo-Newtonian models, the presented relativistic calculations suggest that the treatment of gravity and energy-exchanging neutrino interactions can make differences of even 50%-100% in some quantities and is likely to contribute to a finally successful explosion mechanism on no minor level than hydrodynamical differences between different dimensions.

  19. An energy atlas of five Central American countries. Un atlas energetico de cinco paises Centroamericanos

    SciTech Connect (OSTI)

    Trocki, L.; Newman, C.K.; Gurule, F.; Aragon, P.C.; Peck, C.

    1988-08-01

    In a series of maps and figures, this atlas summarizes what is known about the energy resources and how these resources and oil imports supply the energy needs of five Central American countries: Guatemala, El Salvador, Honduras, Costa Rica, and Panama. The main exploited energy resources are firewood, hydroelectric energy, bagasse from sugar cane residues, and geothermal energy. Limited oil exploration in the region has uncovered modest oil resources only in Guatemala. Peat and small coal deposits are also known to exist but are not presently being exploited. After the description of energy resources, this atlas describes energy supply and demand patterns in each country. It concludes with a description of socioeconomic data that strongly affect energy demand. 4 refs.

  20. Treatability of Stormwater Heavy Metals

    E-Print Network [OSTI]

    Clark, Shirley E.

    1 Treatability of Stormwater Heavy Metals or Breaking the Irreducible Concentration Barrier R. Pitt Technologies for Urban Stormwater Conducted by the University of Alabamay y from 1999 to 2003 · Examined the characteristics and treatability of stormwater heavy metals at selected source areas and at outfalls. · Conducted

  1. Utility Software for ATLAS TDAQ: Summer student project report

    E-Print Network [OSTI]

    Zardilis, Argyris

    2013-01-01

    This is a summer student project report detailing two application developed. One of them aggregates information published by applications in the ATLAS TDAQ environment and the other automatically creates configuration databases describing the system, its components and their interactions.

  2. The Cancer Genome Atlas Pan-Cancer analysis project

    E-Print Network [OSTI]

    Lander, Eric S.

    The Cancer Genome Atlas (TCGA) Research Network has profiled and analyzed large numbers of human tumors to discover molecular aberrations at the DNA, RNA, protein and epigenetic levels. The resulting rich data provide a ...

  3. Searching for Jets in Heavy Ion Collisions

    E-Print Network [OSTI]

    Salur, Sevil

    2008-01-01

    measurements with full jet reconstruction in heavy ionDirect measurement of jets in s N N = 200 GeV Heavy Ion5–12, 2008 Searching for Jets in Heavy Ion Collisions Sevil

  4. J/psi production and elliptic flow in relativistic heavy-ion collisions 

    E-Print Network [OSTI]

    Song, Taesoo; Ko, Che Ming; Lee, Su Houng; Xu, Jun.

    2011-01-01

    Using the two-component model for charmonium production, which includes contributions from both initial hard nucleon-nucleon scattering and from regeneration in the quark-gluon plasma, we study the nuclear modification ...

  5. Anisotropic flow fluctuations in hydro-inspired freeze-out model for relativistic heavy ion collisions

    E-Print Network [OSTI]

    L. V. Bravina; E. S. Fotina; V. L. Korotkikh; I. P. Lokhtin; L. V. Malinina; E. N. Nazarova; S. V. Petrushanko; A. M. Snigirev; E. E. Zabrodin

    2015-11-06

    The LHC data on event-by-event harmonic flow coefficients measured in PbPb collisions at center-of-mass energy 2.76 TeV per nucleon pair are analyzed and interpreted within the HYDJET++ model. To compare the model results with the experimental data the unfolding procedure is employed. The essentially dynamical origin of the flow fluctuations in hydro-inspired freeze-out approach has been established. It is shown that the simple modification of the model via introducing the distribution over spatial anisotropy parameters permits HYDJET++ to reproduce both elliptic and triangular flow fluctuations and related to it eccentricity fluctuations of the initial state at the LHC energy.

  6. Freeze-out in hydrodynamical models in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Magas, V K; Csernai, László P; Grassi, Frédérique; Greiner, W; Hama, Y; Kodama, T; Lázár, Z I; Stöcker, H; Lazar, Zs.I.

    1999-01-01

    Freeze-out of particles across 3-dimensional space-time hypersurface with space-like normal is discussed in a simple kinetic model. The final momentum distribution of emitted particles shows a non-exponential transverse momentum spectrum, which is in quantitative agreement with recently measured SPS pion and $h^-$ spectra.

  7. New Spectroscopy of Heavy Neutron Rich Nuclei: Isomeric Studies Following Relativistic Fragmentation

    SciTech Connect (OSTI)

    M. Pfuetzner; P.H. Regan; Zs. Podolyak; J. Gerl; M. Hellstroem; M. Caamano; P. Mayet; M. Mineva; M. Sawicka; Ch. Schlegel

    1999-12-31

    Gamma spectroscopy methods have been used to search for microsecond isomers among fragmentation products of 1 GeV/nucleon {sup 208}Pb beam. Decays of several known K-isomers in the rare earth region of A {approx} 180 were observed, including the K = 35/2 isomer in {sup 179}W. Several new isomeric decays in the very neutron rich systems, such as {sup 190}W, have been identified. In addition, in the course of this work, a number of neutron rich rare earth isotopes have also been synthesized and identified for the first time.

  8. Contribution of the Reaction Ny-]Nnk to Antikaon Production in Relativistic Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Ko, Che Ming.

    1984-01-01

    implies that more than one projectile nucleon must be involved in converting their kinetic energies into the mass of K . This experi- ment provides, therefore, the possibility of studying nu- clear collective effects, such as Fermi motions, coherent... of the initial nu- cleon in the c.m. system while p' and E' are the momen- tum and energy of the same nucleon in the final state, i.e., p'=[U ?(W+MN) ]' [U (W MN)?]' l2U?, (6) and E'=(p' +MN)' . The quantity op(W;b, ) is the isospin-averaged cross section...

  9. Applications of the LAHET simulation code to relativistic heavy ion detectors

    SciTech Connect (OSTI)

    Waters, L.S.; Gavron, A.

    1991-01-01

    The Los Alamos High Energy Transport (LAHET) simulation code has been applied to test beam data from the lead/scintillator Participant Calorimeter of BNL AGS experiment E814. The LAHET code treats hadronic interactions with the LANL version of the Oak Ridge code HETC. LAHET has now been expanded to handle hadrons with kinetic energies greater than 5 GeV with the FLUKA code, while HETC is used exclusively below 2.0 GeV. FLUKA is phased in linearly between 2.0 and 5.0 GeV. Transport of electrons and photons is done with EGS4, and an interface to the Los Alamos HMCNP3B library based code is provided to analyze neutrons with kinetic energies less than 20 MeV. Excellent agreement is found between the test data and simulation, and results for 2.46 GeV/c protons and pions are illustrated in this article.

  10. Applications of the LAHET simulation code to relativistic heavy ion detectors

    SciTech Connect (OSTI)

    Waters, L.S.; Gavron, A.

    1991-12-31

    The Los Alamos High Energy Transport (LAHET) simulation code has been applied to test beam data from the lead/scintillator Participant Calorimeter of BNL AGS experiment E814. The LAHET code treats hadronic interactions with the LANL version of the Oak Ridge code HETC. LAHET has now been expanded to handle hadrons with kinetic energies greater than 5 GeV with the FLUKA code, while HETC is used exclusively below 2.0 GeV. FLUKA is phased in linearly between 2.0 and 5.0 GeV. Transport of electrons and photons is done with EGS4, and an interface to the Los Alamos HMCNP3B library based code is provided to analyze neutrons with kinetic energies less than 20 MeV. Excellent agreement is found between the test data and simulation, and results for 2.46 GeV/c protons and pions are illustrated in this article.

  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. Scaling properties at freeze-out in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Balewski, Jan T.

    Identified charged pion, kaon, and proton spectra are used to explore the system size dependence of bulk freeze-out properties in Cu+Cu collisions at [sqrt]sNN=200 and 62.4 GeV. The data are studied with hydrodynamically ...

  13. PHYSICAL REVIEW C 80, 064902 (2009) Deuteron production and elliptic flow in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Lin, Zi-wei

    2009-01-01

    V and also with those obtained from the coalescence model based on freeze-out nucleons in the transport model Carolina 27858, USA (Received 13 October 2009; published 3 December 2009) The hadronic transport model ART in the hadronic matter. This new hadronic transport model is used to study the transverse momentum spectrum

  14. Centrality dependence of two-particle correlations in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Park, Youngsoo

    2009-01-01

    Results on the centrality dependence of two-particle correlations in Au+Au collisions at ... 200GeV are presented. A particular focus is devoted to investigating any anomalous behavior in the centrality dependence of ...

  15. Final Report for Project ``Theory of ultra-relativistic heavy-ion

    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(Journal Article) |production at aSciTech ConnectW49BPrecipitation

  16. Relativistic Heavy Ion Collider (RHIC) | U.S. DOE Office of Science (SC)

    Office of Science (SC) Website

    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 AdministrationRobust,Field-effectWorkingLosThe 26thI D-Nicholas

  17. Final Report for Project ``Theory of ultra-relativistic heavy-ion

    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 (Journal Article) |Final Report Document Number(Technical Report) |

  18. Quarkonium production and polarisation with early data at ATLAS

    E-Print Network [OSTI]

    Darren D. Price

    2008-08-25

    One of the first physics results to come out of ATLAS will be an analysis of J/psi and Upsilon production at 14 TeV. I give an overview of the motivation for looking at the theoretical model underlying quarkonium production, ATLAS expected performance and rates for quarkonium reconstruction and ability to separate out various proposed production models with a view to improving our understanding of QCD.

  19. Heavy oil hydroprocessing

    SciTech Connect (OSTI)

    Pratt, R.E.; Nongbri, G.; Clausen, G.A. [Texaco R& D, Port Arthur, TX (United States)] [and others

    1995-12-31

    Many of the crude oils available worldwide are classified as heavy oils (API gravity less than 20). In addition, many of the heavier crude oils are also high in sulfur content. Both the low gravity and high sulfur content make these crude oils difficult to process in many refineries and additional processing equipment is required. Often, deasphalting of the vacuum residuum is one of the processing routes chosen. However, the deasphalted oil (DAO) is often of poor quality and presents problems in processing in existing refinery units. Fixed bed hydrotreater and hydrocracker catalysts are quickly fouled and fluid catalytic cracking units (FCCU) reach regenerator temperature limits with only small amounts of DAO in the feed. Use of the T-STAR ebullated bed process to hydrocrack and upgrade the DAO is an excellent route for making the DAO more palatable to refinery units.

  20. Pseudorapidity correlations in heavy ion collisions from viscous fluid dynamics

    E-Print Network [OSTI]

    Akihiko Monnai; Bjoern Schenke

    2015-09-16

    We demonstrate by explicit calculations in 3+1 dimensional viscous relativistic fluid dynamics how two-particle pseudorapidity correlation functions in heavy ion collisions at the LHC and RHIC depend on the number of particle producing sources and the transport properties of the produced medium. In particular, we present results for the Legendre coefficients of the two-particle pseudorapidity correlation function in Pb+Pb collisions at 2760 GeV and Au+Au collisions at 200 GeV from viscous hydrodynamics with three dimensionally fluctuating initial conditions. Our results suggest that these coefficients provide important constraints on initial state fluctuations and the transport properties of the quark gluon plasma.

  1. Pseudorapidity correlations in heavy ion collisions from viscous fluid dynamics

    E-Print Network [OSTI]

    Monnai, Akihiko

    2015-01-01

    We demonstrate by explicit calculations in 3+1 dimensional viscous relativistic fluid dynamics how two-particle pseudorapidity correlation functions in heavy ion collisions at the LHC and RHIC depend on the number of particle producing sources and the transport properties of the produced medium. In particular, we present results for the Legendre coefficients of the two-particle pseudorapidity correlation function in Pb+Pb collisions at 2760 GeV and Au+Au collisions at 200 GeV from viscous hydrodynamics with three dimensionally fluctuating initial conditions. Our results suggest that these coefficients provide important constraints on initial state fluctuations and the transport properties of the quark gluon plasma.

  2. Interference in Exclusive Vector Meson Production in Heavy Ion Collisions

    E-Print Network [OSTI]

    Spencer R. Klein; Joakim Nystrand

    1999-09-03

    Photons emitted from the electromagnetic fields of relativistic heavy ions can fluctuate into quark anti-quark pairs and scatter from a target nucleus, emerging as vector mesons. These coherent interactions are identifiable by final states consisting of the two nuclei and a vector meson with a small transverse momentum. The emitters and targets can switch roles, and the two possibilities are indistinguishable, so interference may occur. Vector mesons are negative parity so the amplitudes have opposite signs. When the meson transverse wavelength is larger than the impact parameter, the interference is large and destructive. The short-lived vector mesons decay before amplitudes from the two sources can overlap, and so cannot interfere directly. However, the decay products are emitted in an entangled state, and the interference depends on observing the complete final state. The non-local wave function is an example of the Einstein-Podolsky-Rosen paradox.

  3. Accueil > Blog > La Suisse sort un nouveau bijou d'atlas La Suisse sort un nouveau bijou d'atlas

    E-Print Network [OSTI]

    Giger, Christine

    Accueil > Blog > La Suisse sort un nouveau bijou d'atlas La Suisse sort un nouveau bijou d désignées par leur nom. Source 20 Minutes Tweeter ce billet Cette entrée a été publiée dans Blogging, Infos

  4. Relativistic Bohmian mechanics without a preferred foliation

    E-Print Network [OSTI]

    Galvan, Bruno

    2015-01-01

    In non-relativistic Bohmian mechanics the universe is represented by a probability space whose sample space is composed of the Bohmian trajectories. In relativistic Bohmian mechanics an entire class of empirically equivalent probability spaces can be defined, one for every foliation of spacetime. In the literature the hypothesis has been advanced that a single preferred foliation is allowed, and that this foliation derives from the universal wave function by means of a covariant law. In the present paper the opposite hypothesis is advanced, i.e., no law exists for the foliations and therefore all the foliations are allowed. The resulting model of the universe is basically the "union" of all the probability spaces associated with the foliations. This hypothesis is mainly motivated by the fact that any law defining a preferred foliation is empirically irrelevant. It is also argued that the absence of a preferred foliation may reduce the well known conflict between Bohmian mechanics and Relativity.

  5. Double relativistic electron-accelerating mirror

    SciTech Connect (OSTI)

    Andreev, Aleksandr A; Platonov, Konstantin Yu

    2013-05-31

    A numerical simulation of the interaction of a laser pulse with ultrathin targets has revealed a possibility of generating thin dense relativistic electron layers. The maximum kinetic energy of the electron mirror can be gained using an optimal combination of the target thickness and the laser pulse intensity and duration. It is proposed to use an additional (second) laser target, located at an optimal distance from the first target to cut off the laser pulse from the electron layer when the latter gains a maximum kinetic energy. This relativistic electron mirror can be used for efficient generation of 'hard' coherent radiation via counter reflection of an additional (probe) laser pulse from the mirror. (interaction of laser radiation with matter. laser plasma)

  6. Relativistic perturbations in $?$CDM: Eulerian & Lagrangian approaches

    E-Print Network [OSTI]

    Eleonora Villa; Cornelius Rampf

    2015-05-18

    We study the relativistic dynamics of a pressure-less and irrotational fluid of dark matter (CDM) with a cosmological constant ($\\Lambda$), up to second order in cosmological perturbation theory. In our analysis we also account for primordial non-Gaussianity. We consider three gauges: the synchronous-comoving gauge, the Poisson gauge and the total matter gauge, where the first is the unique relativistic Lagrangian frame of reference, and the latters are convenient choices for Eulerian frames. Our starting point is the metric and fluid variables in the Poisson gauge. We then perform a gauge-transformation to the synchronous-comoving gauge, and subsequently to the total matter gauge. Our expressions for the metrics, densities, velocities, and the gauge generators are novel and coincide with known results in the limit of a vanishing cosmological constant.

  7. Exact Relativistic Magnetized halos around Rotating Disks

    E-Print Network [OSTI]

    Antonio C. Gutiérrez-Piñeres; Abraão J. S. Capistrano

    2015-05-15

    The exact relativistic treatment of a rotating disk surrounded by a magnetized material halo is presented. The features of the halo and disk are described by the distributional energy-momentum tensor of a general fluid in canonical form. All the relevant quantities and the metric and electromagnetic potentials are exactly determined by an arbitrary harmonic function only. For instance, the generalized Kuzmin-disk potential is used. The particular class of solutions obtained is asymptotically flat and satisfies all the energy conditions. Moreover, the motion of a charged particle on the halo is described. As far as we know, this is the first relativistic model describing analytically the magnetized halo of a rotating disk.

  8. Newtonian Aspects of General Relativistic Galaxy Models

    E-Print Network [OSTI]

    Aleksandar Rakic; Dominik J. Schwarz

    2008-11-13

    Many cosmological observations call for the existence of dark matter. The most direct evidence for dark matter is inferred from the measured flatness of galactic rotation curves. The latter is based on Newtonian gravity. Alternative approaches to the rotation curve problem by means of general relativity have recently been put forward. The class of models of interest is a subset of the axially symmetric and stationary solutions of Einstein's equations with rotating dust. As a step toward the understanding of general relativistic galaxy models, we analyse rigidly as well as non-rigidly rotating (Post-)Newtonian spacetimes. We find that the Newtonian limit of the considered general relativistic galaxy model leads to Post-Newtonian terms in the metric.

  9. The Spinless Relativistic Woods-Saxon Problem

    E-Print Network [OSTI]

    Wolfgang Lucha; Franz F. Schoberl

    2014-03-14

    Motivated by the observation of a recent renewal of rather strong interest in the description of bound states by (semi-) relativistic equations of motion, we revisit, for the example of the Woods-Saxon interactions, the eigenvalue problem posed by the spinless Salpeter equation and recall various elementary knowledge, considerations, and techniques that practitioners seeking solutions to this specific reduction of the Bethe-Salpeter equation may find helpful.

  10. Bose-Einstein Condensate general relativistic stars

    E-Print Network [OSTI]

    P. H. Chavanis; T. Harko

    2011-08-19

    We analyze the possibility that due to their superfluid properties some compact astrophysical objects may contain a significant part of their matter in the form of a Bose-Einstein condensate. To study the condensate we use the Gross-Pitaevskii equation, with arbitrary non-linearity. By introducing the Madelung representation of the wave function, we formulate the dynamics of the system in terms of the continuity equation and of the hydrodynamic Euler equations. The non-relativistic and Newtonian Bose-Einstein gravitational condensate can be described as a gas, whose density and pressure are related by a barotropic equation of state. In the case of a condensate with quartic non-linearity, the equation of state is polytropic with index one. In the framework of the Thomas-Fermi approximation the structure of the Newtonian gravitational condensate is described by the Lane-Emden equation, which can be exactly solved. The case of the rotating condensate is also discussed. General relativistic configurations with quartic non-linearity are studied numerically with both non-relativistic and relativistic equations of state, and the maximum mass of the stable configuration is determined. Condensates with particle masses of the order of two neutron masses (Cooper pair) and scattering length of the order of 10-20 fm have maximum masses of the order of 2 M_sun, maximum central density of the order of 0.1-0.3 10^16 g/cm^3 and minimum radii in the range of 10-20 km. In this way we obtain a large class of stable astrophysical objects, whose basic astrophysical parameters (mass and radius) sensitively depend on the mass of the condensed particle, and on the scattering length. We also propose that the recently observed neutron stars with masses in the range of 2-2.4 M_sun are Bose-Einstein Condensate stars.

  11. Optimized delta expansion for relativistic nuclear models

    E-Print Network [OSTI]

    G. Krein; R. S. Marques de Carvalho; D. P. Menezes; M. Nielsen; M. B. Pinto

    1997-09-24

    The optimized $\\delta$-expansion is a nonperturbative approach for field theoretic models which combines the techniques of perturbation theory and the variational principle. This technique is discussed in the $\\lambda \\phi^4$ model and then implemented in the Walecka model for the equation of state of nuclear matter. The results obtained with the $\\delta$ expansion are compared with those obtained with the traditional mean field, relativistic Hartree and Hartree-Fock approximations.

  12. Distinct optical properties of relativistically degenerate matter

    SciTech Connect (OSTI)

    Akbari-Moghanjoughi, M.

    2014-06-15

    In this paper, we use the collisional quantum magnetohydrodynamic (CQMHD) model to derive the transverse dielectric function of a relativistically degenerate electron fluid and investigate various optical parameters, such as the complex refractive index, the reflection and absorption coefficients, the skin-depth and optical conductivity. In this model we take into accounts effects of many parameters such as the atomic-number of the constituent ions, the electron exchange, electron diffraction effect and the electron-ion collisions. Study of the optical parameters in the solid-density, the warm-dense-matter, the big-planetary core, and the compact star number-density regimes reveals that there are distinct differences between optical characteristics of the latter and the former cases due to the fundamental effects of the relativistic degeneracy and other quantum mechanisms. It is found that in the relativistic degeneracy plasma regime, such as found in white-dwarfs and neutron star crusts, matter possess a much sharper and well-defined step-like reflection edge beyond the x-ray electromagnetic spectrum, including some part of gamma-ray frequencies. It is also remarked that the magnetic field intensity only significantly affects the plasma reflectivity in the lower number-density regime, rather than the high density limit. Current investigation confirms the profound effect of relativistic degeneracy on optical characteristics of matter and can provide an important plasma diagnostic tool for studying the physical processes within the wide scope of quantum plasma regimes be it the solid-density, inertial-confined, or astrophysical compact stars.

  13. On the concept of relativistic mass

    E-Print Network [OSTI]

    Peter M. Brown

    2007-09-06

    Within the past fifteen years the use of the concept of "relativistic mass" has been on the decline and has been replaced by the concept of "proper mass" (aka "rest mass") - ?simply referred to as "mass" and labeled "m" by its proponents. This decline in usage appears to be due to arguments presented in several journal articles over the last thirty-five years, as well as to standard practices in the field of particle physics. The aforementioned debate consists of arguments as to how the term "mass" should be defined to maximize logic as well as to be less confusing to the layman and people just starting to learn relativity. Lacking in the debate is a clear definition of all types of mass and all its usages in a wide variety of cases. The purpose in this article is to bring a unifying perspective to the subject. In doing so I will explore those things omitted from previous articles on this subject including the importance of point particles vs. extended objects; open vs. closed systems and gravitational mass. Although I argue for the usage of relativistic mass I do "not" argue that proper mass is not an important tool in relativistic dynamics.

  14. Scattering of twisted relativistic electrons by atoms

    E-Print Network [OSTI]

    V. Serbo; I. P. Ivanov; S. Fritzsche; D. Seipt; A. Surzhykov

    2015-05-11

    The Mott scattering of high-energetic twisted electrons by atoms is investigated within the framework of the first Born approximation and Dirac's relativistic equation. Special emphasis is placed on the angular distribution and longitudinal polarization of the scattered electrons. In order to evaluate these angular and polarization properties we consider two experimental setups in which the twisted electron beam collides with either a single well-localized atom or macroscopic atomic target. Detailed relativistic calculations have been performed for both setups and for the electrons with kinetic energy from 10 keV to 1000 keV. The results of these calculations indicate that the emission pattern and polarization of outgoing electrons differ significantly from the scattering of plane-wave electrons and can be very sensitive to the parameters of the incident twisted beam. In particular, it is shown that the angular- and polarization-sensitive Mott measurements may reveal valuable information about, both the transverse and longitudinal components of the linear momentum and the projection of the total angular momentum of twisted electron states. Thus, the Mott scattering emerges as a diagnostic tool for the relativistic vortex beams.

  15. A New ATLAS Muon CSC Readout System with System on Chip Technology...

    Office of Scientific and Technical Information (OSTI)

    A New ATLAS Muon CSC Readout System with System on Chip Technology on ATCA Platform Citation Details In-Document Search Title: A New ATLAS Muon CSC Readout System with System on...

  16. Evolution of the ATLAS Metadata Interface (AMI)

    E-Print Network [OSTI]

    Odier, Jerome; The ATLAS collaboration; Fulachier, Jerome; Lambert, Fabian

    2015-01-01

    The ATLAS Metadata Interface (AMI) can be considered to be a mature application because it has existed for at least 10 years. Over the years, the number of users and the number of functions provided for these users has increased. It has been necessary to adapt the hardware infrastructure in a seamless way so that the Quality of Service remains high. We will describe the evolution of the application from the initial one, using single server with a MySQL backend database, to the current state, where we use a cluster of Virtual Machines on the French Tier 1 Cloud at Lyon, an ORACLE database backend also at Lyon, with replication to CERN using ORACLE streams behind a back-up server.

  17. Performance of the ATLAS Tile calorimeter

    E-Print Network [OSTI]

    Bertoli, Gabriele; The ATLAS collaboration

    2015-01-01

    The Tile Calorimeter (TileCal) of the ATLAS experiment at the LHC is the central hadronic calorimeter designed for energy reconstruction of hadrons, jets, tau­particles and missing transverse energy. TileCal is a scintillator­steel sampling calorimeter and it covers the region of pseudorapidity energies ranging from ~30 MeV to ~2 TeV. The read­out system is responsible for reconstructing the data in real­time. The digitized signals are reconstructed with the Optimal Filtering algorithm, which computes for each channel the signal amplitude, time and quality factor at the required high rate. Each stage of the signal production from scintillation light to the signal reconstruc...

  18. Performance of the ATLAS Tile Calorimeter

    E-Print Network [OSTI]

    Solodkov, Alexander; The ATLAS collaboration

    2015-01-01

    The ATLAS Tile hadronic calorimeter (TileCal) provides highly-segmented energy measurements of incoming particles. It is a key detector for the measurement of hadrons, jets, tau leptons and missing transverse energy. It is also useful for identification and reconstruction of muons due to good signal to noise ratio. The calorimeter consists of thin steel plates and 460,000 scintillating tiles configured into 5000 cells, each viewed by two photomultipliers. The calorimeter response and its readout electronics is monitored to better than 1% using radioactive source, laser and charge injection systems. The calibration and performance of the calorimeter have been established through test beam measurements, cosmic ray muons and the large sample of muons and single hadrons from proton-proton collisions acquired in 2011 and 2012. The results demonstrate that the Tile Calorimeter has performed well within the design requirements and it has given essential contribution to reconstructed objects and physics results.

  19. Top Quark Production Measurements at ATLAS

    E-Print Network [OSTI]

    Robert Calkins; for the ATLAS Collaboration

    2011-10-05

    An overview of top quark production measurements using the ATLAS detector at the LHC is presented. Using 35 pb^-1 of data, we measured the ttbar cross-section in the lepton+jets channel to 13% precision and set limits on the cross-section for the all hadronic decay channel. The measurement in the dilepton channel was performed using 0.70 fb^-1 of data and was combined with the lepton+jets channel result for our most precise ttbar cross-section measurement of \\sigma(ttbar+X) =176 +- 5(stat) +13 -10 (syst) +-7(lumi). Single top production was also measured in the t-channel using 0.70 fb^-1 of data.

  20. Design Study of Longitudinal Dynamics of the Drive Beam in a Relativistic Klystron Two-Beam Accelerator

    E-Print Network [OSTI]

    Li, H.

    2008-01-01

    Westenskow, "Relativistic Klystron Two-Beam Accelerator As AA. Westenskow, "Relativistic Klystron Research for Two-Beamin a Relativistic Klystron Two-Beam Accelerator", Proc. 16

  1. Common Analysis of the Relativistic Klystron and the Standing-Wave Free-Electron Laser Two-Beam Accelerator

    E-Print Network [OSTI]

    Wurtele, Jonathan S.

    2008-01-01

    Powered by a Relativistic Klystron", Phys. Rev. Lett. 11.Analysis the Relativistic Klystron and the Standing-WaveANALYSIS OF THE RELATIVISTIC KLYSTRON AND THE STANDING-WAVE

  2. Heavy Metal Humor: Reconsidering Carnival in Heavy Metal Culture 

    E-Print Network [OSTI]

    Powell, Gary Botts

    2013-06-05

    Bakhtin?s carnivalesque theory by analyzing comedic rhetoric performed by two comedic metal bands. Through the theories of Johan Huizinga and Mikhail Bakhtin, Chapter I: I Play Metal argues that heavy metal culture is a modern carnivalesque play...

  3. Probing QCD with jets, photons and weak bosons at the LHC with ATLAS

    SciTech Connect (OSTI)

    Cooper, Ben [University College London, London (United Kingdom); Collaboration: ATLAS Collaboration

    2012-10-23

    A summary of ATLAS measurements that probe 'hard' QCD interactions in the protonproton collisions of the LHC are presented.

  4. Rankine-Hugoniot Relations in Relativistic Combustion Waves

    E-Print Network [OSTI]

    Gao, Yang

    2012-01-01

    As a foundational element describing relativistic reacting waves of relevance to astrophysical phenomena, the Rankine-Hugoniot relations classifying the various propagation modes of detonation and deflagration are analyzed in the relativistic regime, with the results properly degenerating to the non-relativistic and highlyrelativistic limits. The existence of negative-pressure downstream flows is noted for relativistic shocks, which could be of interest in the understanding of the nature of dark energy. Entropy analysis for relativistic shock waves are also performed for relativistic fluids with different equations of state (EoS), denoting the existence of rarefaction shocks in fluids with adiabatic index \\Gamma < 1 in their EoS. The analysis further shows that weak detonations and strong deflagrations, which are rare phenomena in terrestrial environments, are expected to exist more commonly in astrophysical systems because of the various endothermic reactions present therein. Additional topics of relevanc...

  5. Toward an understanding of the $R_{AA}$ and $v_2$ puzzle for heavy quarks

    E-Print Network [OSTI]

    Francesco Scardina; Santosh K Das; Salvatore Plumari; Jessica I. Bellone; Vincenzo Greco

    2015-09-04

    One of the primary aims of the ongoing nuclear collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies is to create a Quark Gluon Plasma (QGP). The heavy quarks constitutes a unique probe of the QGP properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor $R_{AA}(p_T)$ and the elliptic flow $v_2(p_T)$ related to heavy quark has been observed which challenged all the existing models.\\\\ We discuss how the temperature dependence of the heavy quark drag coefficient can address for a large part of such a puzzle. We have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same $R_{AA}(p_T)$ experimentally observed at RHIC energy. We have found that for the same $R_{AA}(p_T)$ one can generate $2-3$ times more $v_{2}$ depending on the temperature dependence of the heavy quark drag coefficient.

  6. Toward an understanding of the $R_{AA}$ and $v_2$ puzzle for heavy quarks

    E-Print Network [OSTI]

    Scardina, Francesco; Plumari, Salvatore; Bellone, Jessica I; Greco, Vincenzo

    2015-01-01

    One of the primary aims of the ongoing nuclear collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies is to create a Quark Gluon Plasma (QGP). The heavy quarks constitutes a unique probe of the QGP properties. Both at RHIC and LHC energies a puzzling relation between the nuclear modification factor $R_{AA}(p_T)$ and the elliptic flow $v_2(p_T)$ related to heavy quark has been observed which challenged all the existing models.\\\\ We discuss how the temperature dependence of the heavy quark drag coefficient can address for a large part of such a puzzle. We have considered four different models to evaluate the temperature dependence of drag and diffusion coefficients propagating through a quark gluon plasma (QGP). All the four different models are set to reproduce the same $R_{AA}(p_T)$ experimentally observed at RHIC energy. We have found that for the same $R_{AA}(p_T)$ one can generate $2-3$ times more $v_{2}$ depending on the temperature dependence of the heavy quark drag...

  7. HIGH SPATIAL RESOLUTION SOLAR ATLAS IN PROVENCE-ALPES-CTE D'AZUR

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    , realized the Solar Atlas project thanks to the support and funding of local and regional organizationsHIGH SPATIAL RESOLUTION SOLAR ATLAS IN PROVENCE-ALPES-CÔTE D'AZUR Philippe Blanc 1 , Bella Espinar) 1. Introduction Most existing solar atlases cover a continent or a country with a spatial resolution

  8. The KAMM/WAsP Numerical Wind Atlas A powerful ingredient for wind energy planning

    E-Print Network [OSTI]

    The KAMM/WAsP Numerical Wind Atlas A powerful ingredient for wind energy planning J. Badger, N.G. Mortensen, J.C. Hansen Wind Energy Department Risø National Laboratory Great Wall World Renewable Energy Forum Beijing, 23-27 October 2006 #12;Wind Farm Planning National Wind Atlas Environmental Atlases Maps

  9. Relativistic Coulomb excitation within the time dependent superfluid local density approximation

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

    Stetcu, I.; Bertulani, C. A.; Bulgac, A.; Magierski, P.; Roche, K. J.

    2015-01-06

    Within the framework of the unrestricted time-dependent density functional theory, we present for the first time an analysis of the relativistic Coulomb excitation of the heavy deformed open shell nucleus 238U. The approach is based on the superfluid local density approximation formulated on a spatial lattice that can take into account coupling to the continuum, enabling self-consistent studies of superfluid dynamics of any nuclear shape. We compute the energy deposited in the target nucleus as a function of the impact parameter, finding it to be significantly larger than the estimate using the Goldhaber-Teller model. The isovector giant dipole resonance, themore »dipole pygmy resonance, and giant quadrupole modes are excited during the process. As a result, the one-body dissipation of collective dipole modes is shown to lead a damping width ???0.4 MeV and the number of preequilibrium neutrons emitted has been quantified.« less

  10. Relativistic equation of state at subnuclear densities in the Thomas-Fermi approximation

    SciTech Connect (OSTI)

    Zhang, Z. W.; Shen, H., E-mail: shennankai@gmail.com [School of Physics, Nankai University, Tianjin 300071 (China)

    2014-06-20

    We study the non-uniform nuclear matter using the self-consistent Thomas-Fermi approximation with a relativistic mean-field model. The non-uniform matter is assumed to be composed of a lattice of heavy nuclei surrounded by dripped nucleons. At each temperature T, proton fraction Y{sub p} , and baryon mass density ? {sub B}, we determine the thermodynamically favored state by minimizing the free energy with respect to the radius of the Wigner-Seitz cell, while the nucleon distribution in the cell can be determined self-consistently in the Thomas-Fermi approximation. A detailed comparison is made between the present results and previous calculations in the Thomas-Fermi approximation with a parameterized nucleon distribution that has been adopted in the widely used Shen equation of state.

  11. Ionized channel generation of an intense-relativistic electron beam

    DOE Patents [OSTI]

    Frost, Charles A. (Albuquerque, NM); Leifeste, Gordon T. (Albuquerque, NM); Shope, Steven L. (Albuquerque, NM)

    1988-01-01

    A foilless intense relativistic electron beam generator uses an ionized cnel to guide electrons from a cathode passed an anode to a remote location.

  12. Measuring fast electron spectra and laser absorption in relativistic...

    Office of Scientific and Technical Information (OSTI)

    Measuring fast electron spectra and laser absorption in relativistic laser-solid interactions using differential bremsstrahlung photon detectors Citation Details In-Document Search...

  13. Light propagation around a relativistic vortex flow of dielectric medium

    E-Print Network [OSTI]

    B. Linet

    2000-11-06

    We determine the path of the light around a dielectric vortex described by the relativistic vortex flow of a perfect fluid.

  14. Non-relativistic conformal symmetries in fluid mechanics

    E-Print Network [OSTI]

    P. -M. Zhang; P. A. Horvathy

    2009-10-24

    The symmetries of a free incompressible fluid span the Galilei group, augmented with independent dilations of space and time. When the fluid is compressible, the symmetry is enlarged to the expanded Schroedinger group, which also involves, in addition, Schroedinger expansions. While incompressible fluid dynamics can be derived as an appropriate non-relativistic limit of a conformally-invariant relativistic theory, the recently discussed Conformal Galilei group, obtained by contraction from the relativistic conformal group, is not a symmetry. This is explained by the subtleties of the non-relativistic limit.

  15. Acoustic geometry for general relativistic barotropic irrotational fluid flow

    E-Print Network [OSTI]

    Visser, Matt

    2010-01-01

    "Acoustic spacetimes", in which techniques of differential geometry are used to investigate sound propagation in moving fluids, have attracted considerable attention over the last few decades. Most of the models currently considered in the literature are based on non-relativistic barotropic irrotational fluids, defined in a flat Newtonian background. The extension, first to special relativistic barotropic fluid flow, and then to general relativistic barotropic fluid flow in an arbitrary background, is less straightforward than it might at first appear. In this article we provide a pedagogical and simple derivation of the general relativistic "acoustic spacetime" in an arbitrary (d+1) dimensional curved-space background.

  16. LCLS Heavy Met Outgassing Tests

    SciTech Connect (OSTI)

    Kishiyama, K. I.

    2010-12-01

    A Heavy Met that is 95% tungsten, 3% nickel and 2% iron and sintered to 100% density and is Ultra High Vacuum (UHV) compatible is proposed for use as the X-ray slit in the Front End Enclosure and the Fixed Mask for the Linac Coherent Light Source (LCLS). The Heavy Met was tested in the LLNL Vacuum Sciences and Engineering Lab (VSEL) to determine its outgassing rate and its overall compatibility with the vacuum requirements for LCLS.

  17. Heavy Flavour in a Nutshell

    E-Print Network [OSTI]

    Robert W. Lambert

    2011-05-06

    Moriond QCD brings together particle physicists of varied interests. This review and introduction to heavy flavour physics is aimed at those not in the heavy-flavour field to describe the motivation and methodology of precision flavour physics, and introduce the most tantalising searches for new physics. The LHC experiments are expected to make great inroads into constraining the new physics parameter space and discover the new physics which I will argue \\emph{must} be present to describe our observed universe.

  18. Expected Performance of the ATLAS Experiment - Detector, Trigger and Physics

    SciTech Connect (OSTI)

    Aad, G.; Abat, E.; Abbott, B.; Abdallah, J.; Abdelalim, A.A.; Abdesselam, A.; Abdinov, O.; Abi, B.; Abolins, M.; Abramowicz, H.; Acharya, Bobby Samir; Adams, D.L.; Addy, T.N.; Adorisio, C.; Adragna, P.; Adye, T.; Aguilar-Saavedra, J.A.; Aharrouche, M.; Ahlen, S.P.; Ahles, F.; Ahmad, A.; /SUNY, Albany /Alberta U. /Ankara U. /Annecy, LAPP /Argonne /Arizona U. /Texas U., Arlington /Athens U. /Natl. Tech. U., Athens /Baku, Inst. Phys. /Barcelona, IFAE /Belgrade U. /VINCA Inst. Nucl. Sci., Belgrade /Bergen U. /LBL, Berkeley /Humboldt U., Berlin /Bern U., LHEP /Birmingham U. /Bogazici U. /INFN, Bologna /Bologna U.

    2011-11-28

    The Large Hadron Collider (LHC) at CERN promises a major step forward in the understanding of the fundamental nature of matter. The ATLAS experiment is a general-purpose detector for the LHC, whose design was guided by the need to accommodate the wide spectrum of possible physics signatures. The major remit of the ATLAS experiment is the exploration of the TeV mass scale where groundbreaking discoveries are expected. In the focus are the investigation of the electroweak symmetry breaking and linked to this the search for the Higgs boson as well as the search for Physics beyond the Standard Model. In this report a detailed examination of the expected performance of the ATLAS detector is provided, with a major aim being to investigate the experimental sensitivity to a wide range of measurements and potential observations of new physical processes. An earlier summary of the expected capabilities of ATLAS was compiled in 1999 [1]. A survey of physics capabilities of the CMS detector was published in [2]. The design of the ATLAS detector has now been finalised, and its construction and installation have been completed [3]. An extensive test-beam programme was undertaken. Furthermore, the simulation and reconstruction software code and frameworks have been completely rewritten. Revisions incorporated reflect improved detector modelling as well as major technical changes to the software technology. Greatly improved understanding of calibration and alignment techniques, and their practical impact on performance, is now in place. The studies reported here are based on full simulations of the ATLAS detector response. A variety of event generators were employed. The simulation and reconstruction of these large event samples thus provided an important operational test of the new ATLAS software system. In addition, the processing was distributed world-wide over the ATLAS Grid facilities and hence provided an important test of the ATLAS computing system - this is the origin of the expression 'CSC studies' ('computing system commissioning'), which is occasionally referred to in these volumes. The work reported does generally assume that the detector is fully operational, and in this sense represents an idealised detector: establishing the best performance of the ATLAS detector with LHC proton-proton collisions is a challenging task for the future. The results summarised here therefore represent the best estimate of ATLAS capabilities before real operational experience of the full detector with beam. Unless otherwise stated, simulations also do not include the effect of additional interactions in the same or other bunch-crossings, and the effect of neutron background is neglected. Thus simulations correspond to the low-luminosity performance of the ATLAS detector. This report is broadly divided into two parts: firstly the performance for identification of physics objects is examined in detail, followed by a detailed assessment of the performance of the trigger system. This part is subdivided into chapters surveying the capabilities for charged particle tracking, each of electron/photon, muon and tau identification, jet and missing transverse energy reconstruction, b-tagging algorithms and performance, and finally the trigger system performance. In each chapter of the report, there is a further subdivision into shorter notes describing different aspects studied. The second major subdivision of the report addresses physics measurement capabilities, and new physics search sensitivities. Individual chapters in this part discuss ATLAS physics capabilities in Standard Model QCD and electroweak processes, in the top quark sector, in b-physics, in searches for Higgs bosons, supersymmetry searches, and finally searches for other new particles predicted in more exotic models.

  19. BioPower Atlas and BioFuels Atlas | Open Energy Information

    Open Energy Info (EERE)

    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 Home Page on Google Bookmark EERE: Alternative Fuels Data Center Home Page on QA:QA J-E-1 SECTION J APPENDIX E LISTStar Energy LLC Jump to:Greece:BajoBelpower SrlHydroelectricBioCleanBioPowerAtlas

  20. Studies of beam dynamics in relativistic klystron two-beam accelerators

    E-Print Network [OSTI]

    Lidia, Steven M.

    1999-01-01

    Yu. Lett, Relativistic klystron two-beam accelerator. Phys.S.M. Lidia et al. Relativistic klystron two-beam acceleratorPlasma Set. , Relativistic klystron two-beam accelerator. [

  1. Scalable Database Access Technologies for ATLAS Distributed Computing

    E-Print Network [OSTI]

    A. Vaniachine; for the ATLAS Collaboration

    2009-10-02

    ATLAS event data processing requires access to non-event data (detector conditions, calibrations, etc.) stored in relational databases. The database-resident data are crucial for the event data reconstruction processing steps and often required for user analysis. A main focus of ATLAS database operations is on the worldwide distribution of the Conditions DB data, which are necessary for every ATLAS data processing job. Since Conditions DB access is critical for operations with real data, we have developed the system where a different technology can be used as a redundant backup. Redundant database operations infrastructure fully satisfies the requirements of ATLAS reprocessing, which has been proven on a scale of one billion database queries during two reprocessing campaigns of 0.5 PB of single-beam and cosmics data on the Grid. To collect experience and provide input for a best choice of technologies, several promising options for efficient database access in user analysis were evaluated successfully. We present ATLAS experience with scalable database access technologies and describe our approach for prevention of database access bottlenecks in a Grid computing environment.

  2. Direct photon emission in Heavy Ion Collisions from Microscopic Transport Theory and Fluid Dynamics

    E-Print Network [OSTI]

    Bjoern Baeuchle; Marcus Bleicher

    2010-03-29

    Direct photon emission in heavy-ion collisions is calculated within a relativistic micro+macro hybrid model and compared to the microscopic transport model UrQMD. In the hybrid approach, the high-density part of the collision is calculated by an ideal 3+1-dimensional hydrodynamic calculation, while the early (pre-equilibrium-) and late (rescattering-) phase are calculated with the transport model. Different scenarios of the transition from the macroscopic description to the transport model description and their effects are studied. The calculations are compared to measurements by the WA98-collaboration and predictions for the future CBM-experiment are made.

  3. Constraining the equation of state of superhadronic matter from heavy-ion collisions

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

    Pratt, Scott; Sorensen, Paul; Sangaline, Evan; Wang, Hui

    2015-05-19

    The equation of state of QCD matter for temperatures near and above the quark-hadron transition (~165 MeV) is inferred within a Bayesian framework through the comparison of data from the Relativistic Heavy Ion Collider and from the Large Hadron Collider to theoretical models. State-of-the-art statistical techniques are applied to simultaneously analyze multiple classes of observables while varying 14 independent model parameters. Thus, the resulting posterior distribution over possible equations of state is consistent with results from lattice gauge theory.

  4. K+ production in baryon-baryon and heavy-ion collisions 

    E-Print Network [OSTI]

    Li, GQ; Ko, Che Ming; Chung, WS.

    1998-01-01

    Kaon production cross sections in nucleon-nucleon, nucleon-Delta, and Delta-Delta interactions are studied in a boson exchange model. For the latter two interactions, the exchanged pion can be on-mass shell...only contributions due to a virtual pion an included via the Peierls method by taking into account the finite Delta width. With these cross sections and also those for pion-baryon interactions, subthreshold kaon production from heavy-ion collisions is studied in the relativistic transport model....

  5. Gravity duals for non-relativistic CFTs

    E-Print Network [OSTI]

    Koushik Balasubramanian; John McGreevy

    2008-08-01

    We attempt to generalize the AdS/CFT correspondence to non-relativistic conformal field theories which are invariant under Galilean transformations. Such systems govern ultracold atoms at unitarity, nucleon scattering in some channels, and more generally, a family of universality classes of quantum critical behavior. We construct a family of metrics which realize these symmetries as isometries. They are solutions of gravity with negative cosmological constant coupled to pressureless dust. We discuss realizations of the dust, which include a bulk superconductor. We develop the holographic dictionary and compute some two-point correlators. A strange aspect of the correspondence is that the bulk geometry has two extra noncompact dimensions.

  6. A priori estimates for relativistic liquid bodies

    E-Print Network [OSTI]

    Todd A. Oliynyk

    2014-12-30

    We demonstrate that a sufficiently smooth solution of the relativistic Euler equations that represents a dynamical compact liquid body, when expressed in Lagrangian coordinates, determines a solution to a system of non-linear wave equations with acoustic boundary conditions. Using this wave formulation, we prove that these solutions satisfy energy estimates without loss of derivatives. Importantly, our wave formulation does not require the liquid to be irrotational, and the energy estimates do not rely on divergence and curl type estimates employed in previous works.

  7. A priori estimates for relativistic liquid bodies

    E-Print Network [OSTI]

    Oliynyk, Todd A

    2015-01-01

    We demonstrate that a sufficiently smooth solution of the relativistic Euler equations that represents a dynamical compact liquid body, when expressed in Lagrangian coordinates, determines a solution to a system of non-linear wave equations with acoustic boundary conditions. Using this wave formulation, we prove that these solutions satisfy energy estimates without loss of derivatives. Importantly, our wave formulation does not require the liquid to be irrotational, and the energy estimates do not rely on divergence and curl type estimates employed in previous works.

  8. Microengineering laser plasma interactions at relativistic intensities

    E-Print Network [OSTI]

    Jiang, S; Audesirk, H; George, K M; Snyder, J; Krygier, A; Lewis, N S; Schumacher, D W; Pukhov, A; Freeman, R R; Akli, K U

    2015-01-01

    We report on the first successful proof-of-principle experiment to manipulate laser-matter interactions on the microscale using highly ordered Si microwire arrays. The interaction of a high contrast short pulse laser with a flat target via periodic Si microwires yields a substantial enhancement in both total and cut-off energies of the produced electron beam. The self generated electric and magnetic fields behave as an electromagnetic lens that confines and guides electrons between the microwires as they acquire relativistic energies via direct laser acceleration (DLA).

  9. An X-band overmoded relativistic klystron

    SciTech Connect (OSTI)

    Xiao, Renzhen; Chen, Changhua; Li, Jiawei; Bai, Xianchen [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Deng, Yuqun [Science and Technology on High Power Microwave Laboratory, Northwest Institute of Nuclear Technology, Xi'an 710024 (China); Department of Engineering Physics, Tsinghua University, Beijing 100084 (China)

    2014-11-15

    An X-band overmoded relativistic klystron is proposed, the operation mode of which is the TM{sub 02} mode. The drift tube could not cut off the TM{sub 01} mode; isolating the buncher cavity from the input cavity is achieved by introducing a sectional RF lossy material. Microwaves are extracted from the modulated electron beam using a cylindrical waveguide, rather than a coaxial waveguide; thereby, the output structure is significantly simplified. Particle-in-cell simulations show that microwaves with power of 1.28?GW and frequency of 9.30?GHz can be obtained, corresponding to an efficiency of 32% and relative bandwidth of about 8%.

  10. Friedel Oscillations in Relativistic Nuclear Matter

    E-Print Network [OSTI]

    J. Diaz Alonso; E. Gallego; A. Perez

    1994-07-01

    We calculate the low-momentum N-N effective potential obtained in the OBE approximation, inside a nuclear plasma at finite temperature, as described by the relativistic $ \\sigma $-$ \\omega $ model. We analyze the screening effects on the attractive part of the potential in the intermediate range as density or temperature increase. In the long range the potential shows Friedel-like oscillations instead of the usual exponential damping. These oscillations arise from the sharp edge of the Fermi surface and should be encountered in any realistic model of nuclear matter.

  11. Imperfect relativistic mirrors in the quantum regime

    SciTech Connect (OSTI)

    Mendonça, J. T., E-mail: titomend@ist.utl.pt [IPFN, Instituto Superior Técnico, 1049-001 Lisboa (Portugal); Serbeto, A., E-mail: serbeto@if.uff.br [Instituto de Física, Universidade Federal Fluminense, 24210-340 RJ (Brazil); Galvão, R. M. O., E-mail: rgalvao@if.usp.br [Instituto de Física, Universidade de São Paulo, 05508-090 SP (Brazil)

    2014-05-15

    The collective backscattering of intense laser radiation by energetic electron beams is considered in the relativistic quantum regime. Exact solutions for the radiation field are obtained, for arbitrary electron pulse shapes and laser intensities. The electron beams act as imperfect nonlinear mirrors on the incident laser radiation. This collective backscattering process can lead to the development of new sources of ultra-short pulse radiation in the gamma-ray domain. Numerical examples show that, for plausible experimental conditions, intense pulses of gamma-rays, due to the double Doppler shift of the harmonics of the incident laser radiation, can be produced using the available technology, with durations less than 1 as.

  12. Relativistic self-focusing in underdense plasma

    SciTech Connect (OSTI)

    Feit, M.D.; Garrison, J.C.; Komashko, A.; Musher, J.L.; Rubenchik, A.M.; Turistsyn, S.K.

    1997-04-24

    In the present paper, we discuss light self-focusing in underdense (nrelativistic self-focusing including ion dynamics will be presented in second part of the paper. In particular, we will demonstrate the formation of empty, wide channels in underdense plasma in the wake of the laser pulse. we discuss the applicability of our results to real situations and possible consequences for the ``Fast Ignitor`` project.

  13. Mesons: Relativistic Bound States with String Tension

    E-Print Network [OSTI]

    Anishetty, R; Anishetty, Ramesh; Kudtarkar, Santosh Kumar

    2003-01-01

    A systematic method of analysing Bethe-Salpeter equation using spectral representation for the relativistic bound state wave function is given. This has been explicitly applied in the context of perturbative QCD with string tension in the $1 \\over N$ expansion. We show that there are only a few stable bound state mesons due to the small "threshold mass"(constituent mass) of quarks. The asymptotic properties of the bound states are analytically analysed. The spectrum is derived analytically and compared phenomenologically. Chiral symmetry breaking and PCAC results are demonstrated. We make a simple minded observation to determine the size of the bound states as a function of the energy of the boundstate.

  14. Relativistic Random Phase Approximation At Finite Temperature

    SciTech Connect (OSTI)

    Niu, Y. F.; Paar, N.; Vretenar, D.; Meng, J.

    2009-08-26

    The fully self-consistent finite temperature relativistic random phase approximation (FTRRPA) has been established in the single-nucleon basis of the temperature dependent Dirac-Hartree model (FTDH) based on effective Lagrangian with density dependent meson-nucleon couplings. Illustrative calculations in the FTRRPA framework show the evolution of multipole responses of {sup 132}Sn with temperature. With increased temperature, in both monopole and dipole strength distributions additional transitions appear in the low energy region due to the new opened particle-particle and hole-hole transition channels.

  15. Stability of relativistic plasma-vacuum interfaces

    E-Print Network [OSTI]

    Yuri Trakhinin

    2011-11-18

    We study the plasma-vacuum interface problem in relativistic magnetohydrodynamics for the case when the plasma density does not go to zero continuously, but jumps. In the vacuum region we consider the Maxwell equations for electric and magnetic fields. We show that a sufficiently large vacuum electric field can make the planar interface violently unstable. By using a suitable secondary symmetrization of the vacuum Maxwell equations, we find a sufficient condition that precludes violent instabilities. Under this condition we derive an energy a priori estimate in the anisotropic weighted Sobolev space $H^1_*$ for the variable coefficients linearized problem for nonplanar plasma-vacuum interfaces.

  16. DAQ hardware and software development for the ATLAS Pixel Detector

    E-Print Network [OSTI]

    Stramaglia, Maria Elena; The ATLAS collaboration

    2015-01-01

    In 2014, the Pixel Detector of the ATLAS experiment has been extended by about 12 million pixels thanks to the installation of the Insertable B-Layer (IBL). Data-taking and tuning procedures have been implemented along with newly designed read-out hardware to support high bandwidth for data readout and calibration. The hardware is supported by an embedded software stack running on the read-out boards. The same boards will be used to upgrade the read-out bandwidth for the two outermost layers of the ATLAS Pixel Barrel (54 million pixels). We present the IBL read-out hardware and the supporting software architecture used to calibrate and operate the 4-layer ATLAS Pixel detector. We discuss the technical implementations and status for data taking, validation of the DAQ system in recent cosmic ray data taking, in-situ calibrations, and results from additional tests in preparation for Run 2 at the LHC.

  17. Commissioning of the EBIS-based heavy ion preinjector at Brookhaven

    SciTech Connect (OSTI)

    Alessi, J.; Beebe, E.; Binello, S.; Hoff, L.; Kondo, K.; Lambiase, R.; LoDestro, V.; Mapes, M.; McNerney, A.; Morris, J.; Okamura, M.; Pikin, A.I.; Raparia, D.; Ritter, J.; Smart, L.; Snydstrup, L.; Wilinski, M.; Zaltsman, A.; Schempp, A.; Ratzinger, U.; Kanesue, T.

    2010-09-12

    The status is presented of the commissioning of a new heavy ion preinjector at Brookhaven National Laboratory. This preinjector uses an Electron Beam Ion Source (EBIS), and an RFQ and IH Linac, both operating at 100.625 MHz, to produce 2 MeV/u ions of any species for use, after further acceleration, at the Relativistic Heavy Ion Collider (RHIC) and the NASA Space Radiation Laboratory (NSRL). Among the increased capabilities provided by this preinjector are the ability to produce ions of any species, and the ability to switch between multiple species in 1 second, to simultaneously meet the needs of both science programs. For initial setup, helium beam from EBIS was injected and circulated in the Booster synchrotron. Following this, accelerated Au{sup 32+} and Fe{sup 20+} beams were transported to the Booster injection point, fulfilling DOE requirements for project completion.

  18. High harmonic generation in the relativistic *, A. GOPAL2

    E-Print Network [OSTI]

    Loss, Daniel

    LETTERS High harmonic generation in the relativistic limit B. DROMEY1 , M. ZEPF1 *, A. GOPAL2 , K, measurements with unprecedented temporal resolution1­6 . Harmonics from laser­solid target interactions have of harmonic efficiency to high orders by driving harmonic production to the relativistic limit1 . Here we

  19. Relativistic field theory of neutron stars and their hyperon populations

    SciTech Connect (OSTI)

    Glendenning, N.K.

    1986-01-01

    The nuclear many-body problem is examined by means of the formulation of an effective relativistic field theory of interacting hadrons. A relativistic field theory of hadronic matter is especially appropriate for the description of hot or dense matter, because of the appearance of antiparticles and higher baryon resonances and because it automatically respects causality. 8 refs., 7 figs., 1 tab. (WRF)

  20. Relativistic Positioning Systems: The Emission Coordinates

    E-Print Network [OSTI]

    Bartolomé Coll; José MarÍa Pozo

    2006-07-18

    This paper introduces some general properties of the gravitational metric and the natural basis of vectors and covectors in 4-dimensional emission coordinates. Emission coordinates are a class of space-time coordinates defined and generated by 4 emitters (satellites) broadcasting their proper time by means of electromagnetic signals. They are a constitutive ingredient of the simplest conceivable relativistic positioning systems. Their study is aimed to develop a theory of these positioning systems, based on the framework and concepts of general relativity, as opposed to introducing `relativistic effects' in a classical framework. In particular, we characterize the causal character of the coordinate vectors, covectors and 2-planes, which are of an unusual type. We obtain the inequality conditions for the contravariant metric to be Lorentzian, and the non-trivial and unexpected identities satisfied by the angles formed by each pair of natural vectors. We also prove that the metric can be naturally split in such a way that there appear 2 parameters (scalar functions) dependent exclusively on the trajectory of the emitters, hence independent of the time broadcast, and 4 parameters, one for each emitter, scaling linearly with the time broadcast by the corresponding satellite, hence independent of the others.