Sample records for heavy ion collider

  1. RHIC | Relativistic Heavy Ion Collider

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

    Photo of LINAC The Relativistic Heavy Ion Collider (RHIC) is a world-class particle accelerator at Brookhaven National Laboratory where physicists are exploring the most...

  2. Electron Cooling of the Relativistic Heavy Ion Collider

    E-Print Network [OSTI]

    Benchmarking experiments Also: Cost and schedule. Work in progress. #12;Electron cooling group. Reporting to Thomas Roser systems Yuri Eidelman, electron cooling simulations. Harald Hahn, Superconducting RF and HOMs. AdyElectron Cooling of the Relativistic Heavy Ion Collider: Overview Ilan Ben-Zvi Collider

  3. Electron Cooling of the Relativistic Heavy Ion Collider

    E-Print Network [OSTI]

    Electron Cooling of the Relativistic Heavy Ion Collider: Overview Ilan Ben-Zvi Collider-Accelerator Department's Machine Advisory Committee January 2006 #12;Motivation · The motivation for electron coolingRHIC are on the DOE's 20 years facilities plan. RHIC luminosity decay (3.5 hours) #12;What is special about cooling

  4. Ion colliders

    SciTech Connect (OSTI)

    Fischer, W.

    2011-12-01T23:59:59.000Z

    Ion colliders are research tools for high-energy nuclear physics, and are used to test the theory of Quantum Chromo Dynamics (QCD). The collisions of fully stripped high-energy ions create matter of a temperature and density that existed only microseconds after the Big Bang. Ion colliders can reach higher densities and temperatures than fixed target experiments although at a much lower luminosity. The first ion collider was the CERN Intersecting Storage Ring (ISR), which collided light ions [77Asb1, 81Bou1]. The BNL Relativistic Heavy Ion Collider (RHIC) is in operation since 2000 and has collided a number of species at numerous energies. The CERN Large Hadron Collider (LHC) started the heavy ion program in 2010. Table 1 shows all previous and the currently planned running modes for ISR, RHIC, and LHC. All three machines also collide protons, which are spin-polarized in RHIC. Ion colliders differ from proton or antiproton colliders in a number of ways: the preparation of the ions in the source and the pre-injector chain is limited by other effects than for protons; frequent changes in the collision energy and particle species, including asymmetric species, are typical; and the interaction of ions with each other and accelerator components is different from protons, which has implications for collision products, collimation, the beam dump, and intercepting instrumentation devices such a profile monitors. In the preparation for the collider use the charge state Z of the ions is successively increased to minimize the effects of space charge, intrabeam scattering (IBS), charge change effects (electron capture and stripping), and ion-impact desorption after beam loss. Low charge states reduce space charge, intrabeam scattering, and electron capture effects. High charge states reduce electron stripping, and make bending and acceleration more effective. Electron stripping at higher energies is generally more efficient. Table 2 shows the charge states and energies in the RHIC and LHC injector chains for the heaviest ion species used to date. The RHIC pulsed sputter source (PSC) and Tandem electrostatic accelerator are being replaced by an Electron Beam Ion Source (EBIS), Radio Frequency Quadrupole (RFQ) and short linac [08Ale1]. With EBIS beams of any element can be prepared for RHIC including uranium and spin-polarized 3He. At CERN an ECR ion source is used, followed by an RFQ and Linac. The ions are then accumulated, electron cooled, and accelerated in LEIR. After transfer to and acceleration in the PS, ion beams are injected into the SPS.

  5. Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider

    E-Print Network [OSTI]

    Bruce, R; Fischer, W; Jowett, J M

    2010-01-01T23:59:59.000Z

    We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon 197Au79+ beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both meth...

  6. Strangelet Search at the BNL Relativistic Heavy Ion Collider

    SciTech Connect (OSTI)

    Ritter, Ha

    2005-11-27T23:59:59.000Z

    We have searched for strangelets in a triggered sample of 61 million central (top 4percent) Au+Au collisions at sqrt sNN = 200 GeV near beam rapidities at the STAR solenoidal tracker detector at the BNL Relativistic Heavy Ion Collider. We have sensitivity to metastable strangelets with lifetimes of order>_0.1 ns, in contrast to limits over ten times longer in BNL Alternating Gradient Synchrotron (AGS) studies and longer still at the CERN Super Proton Synchrotron (SPS). Upper limits of a few 10-6 to 10-7 per central Au+Au collision are set for strangelets with mass>~;;30 GeV/c2.

  7. Time evolution of the luminosity of colliding heavy-ion beams in BNL Relativistic Heavy Ion Collider and CERN Large Hadron Collider

    E-Print Network [OSTI]

    R. Bruce; M. Blaskiewicz; W. Fischer; J. M. Jowett

    2010-09-08T23:59:59.000Z

    We have studied the time evolution of the heavy ion luminosity and bunch intensities in the Relativistic Heavy Ion Collider (RHIC), at BNL, and in the Large Hadron Collider (LHC), at CERN. First, we present measurements from a large number of RHIC stores (from Run 7), colliding 100 GeV/nucleon Au beams without stochastic cooling. These are compared with two different calculation methods. The first is a simulation based on multi-particle tracking taking into account collisions, intrabeam scattering, radiation damping, and synchrotron and betatron motion. In the second, faster, method, a system of ordinary differential equations with terms describing the corresponding effects on emittances and bunch populations is solved numerically. Results of the tracking method agree very well with the RHIC data. With the faster method, significant discrepancies are found since the losses of particles diffusing out of the RF bucket due to intrabeam scattering are not modeled accurately enough. Finally, we use both methods to make predictions of the time evolution of the future Pb beams in the LHC at injection and collision energy. For this machine, the two methods agree well.

  8. Feasibility study of a laser ion source for primary ion injection into the Relativistic Heavy Ion Collider electron beam ion sourcea...

    E-Print Network [OSTI]

    chamber to be able to change ion species on a pulse by pulse basis. The optimal plasma drift length variesFeasibility study of a laser ion source for primary ion injection into the Relativistic Heavy Ion Collider electron beam ion sourcea... Takeshi Kanesue Department of Applied Quantum Physics and Nuclear

  9. Jet-Underlying Event Separation Method for Heavy Ion Collisions at the Relativistic Heavy Ion Collider

    E-Print Network [OSTI]

    J. A. Hanks; A. M. Sickles; B. A. Cole; A. Franz; M. P. McCumber; D. P. Morrison; J. L. Nagle; C. H. Pinkenburg; B. Sahlmueller; P. Steinberg; M. von Steinkirch; M. Stone

    2012-04-10T23:59:59.000Z

    Reconstructed jets in heavy ion collisions are a crucial tool for understanding the quark-gluon plasma. The separation of jets from the underlying event is necessary particularly in central heavy ion reactions in order to quantify medium modifications of the parton shower and the response of the surrounding medium itself. There have been many methods proposed and implemented for studying the underlying event substructure in proton-proton and heavy ion collisions. In this paper, we detail a method for understanding underlying event contributions in Au+Au collisions at $\\sqrt{s_{NN}}$ = 200 GeV utilizing the HIJING event generator. This method, extended from previous work by the ATLAS collaboration, provides a well-defined association of "truth jets" from the fragmentation of hard partons with "reconstructed jets" using the anti-$k_T$ algorithm. Results presented here are based on an analysis of 750M minimum bias HIJING events. We find that there is a substantial range of jet energies and radius parameters where jets are well separated from the background fluctuations (often termed "fake jets") that make jet measurements at RHIC a compelling physics program.

  10. The Multi-Purpose Detector for NICA heavy-Ion Collider at JINR

    SciTech Connect (OSTI)

    Rogachevsky, O. V., E-mail: rogachevsky@jinr.ru [JINR, Veksler and Baldin Laboratory on High Energy Physics (Russian Federation)

    2012-05-15T23:59:59.000Z

    The Multi-Purpose Detector (MPD) is designed to study heavy-ion collisions at the Nuclotron-based heavy Ion Collider fAcility (NICA) at JINR, Dubna. Its main components located inside a superconducting solenoid are a tracking system composed of a silicon microstrip vertex detector followed by a large volume time-projection chamber, a time-of-flight system for particle identification and a barrel electromagnetic calorimeter. A zero degree hadron calorimeter is designed specifically to measure the energy of spectators. In this paper, all parts of the apparatus are described and their tracking and particle identification parameters are discussed in some detail.

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

    ScienceCinema (OSTI)

    Brookhaven Lab - Fulvia Pilat

    2010-01-08T23:59:59.000Z

    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

  12. Longitudinal Decorrelation of Anisotropic Flows in Heavy-ion Collisions at the CERN Large Hadron Collider

    E-Print Network [OSTI]

    Long-Gang Pang; Guang-You Qin; Victor Roy; Xin-Nian Wang; Guo-Liang Ma

    2015-04-22T23:59:59.000Z

    Fluctuations in the initial transverse energy-density distribution lead to anisotropic flows as observed in central high-energy heavy-ion collisions. Studies of longitudinal fluctuations of the anisotropic flows can shed further light on the initial conditions and dynamical evolution of the hot quark-gluon matter in these collisions. Correlations between anisotropic flows with varying pseudorapidity gaps in Pb+Pb collisions at the CERN Large Hadron Collider are investigated using both an event-by-event (3+1)-D ideal hydrodynamical model with fluctuating initial conditions and the a multiphase transport (AMPT) Monte Carlo model for high-energy heavy-ion collisions. Anisotropic flows at different pseudorapidities are found to become significantly decorrelated with increasing pseudo-rapidity gaps due to longitudinal fluctuations in the initial states of heavy-ion collisions. The longitudinal correlation of the elliptic flow shows a strong centrality dependence while the correlation of the triangular flow is independent of the centrality. Longitudinal fluctuations as a source of the decorrelation are further shown to consist of a twist or gradual rotation in flow angles between the forward and backward direction and additional fluctuations on top of the twist. Within the AMPT model, longitudinal correlations of anisotropic flows are also found to depend on the value of partonic cross sections. The implicatiosn of constraining the initial conditions and shear viscosity to entropy density ratio of the partonic matter in high-energy heavy-ion collisions are also discussed.

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

    SciTech Connect (OSTI)

    Liu, C. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Marusic, A. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.; Minty, M. [Brookhaven National Lab. (BNL), Upton, NY (United States). Collider-Accelerator Dept.

    2014-09-09T23:59:59.000Z

    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.

  14. 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.

    2006-01-01T23:59:59.000Z

    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...

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

    SciTech Connect (OSTI)

    Sickles, Anne [BNL Physics Department

    2014-03-19T23:59:59.000Z

    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.

  16. 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.

    2008-01-01T23:59:59.000Z

    system of deconfined partonic matter, the quark gluon plasma (QGP) [1]. Matter under such extreme conditions can be studied in the laboratory by colliding nuclei at very high energies. The Relativistic Heavy-Ion Collider (RHIC) at Brookhaven National... C. Zhong,39 J. Zhou,36 R. Zoulkarneev,13 Y. Zoulkarneeva,13 and J. X. Zuo39 (STAR Collaboration) 1Argonne National Laboratory, Argonne, Illinois 60439, USA 2University of Birmingham, Birmingham, United Kingdom 3Brookhaven National Laboratory...

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

    SciTech Connect (OSTI)

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

    1990-01-01T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Pratt, Scott; Schlichting, Soeren; Gavin, Sean [Department of Physics and Astronomy and National Superconducting Cyclotron Laboratory, Michigan State University, East Lansing, Michigan 48824 (United States); Department of Physics, Wayne State University, Detroit, Michigan 48201 (United States)

    2011-08-15T23:59:59.000Z

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

  19. Fluctuations of charge separation perpendicular to the event plane and local parity violation in ?S[subscript NN] = 200 GeV Au + Au collisions at the BNL Relativistic Heavy Ion Collider

    E-Print Network [OSTI]

    Balewski, Jan T.

    Previous experimental results based on data (?15 × 10[superscript 6] events) collected by the STAR detector at the BNL Relativistic Heavy Ion Collider suggest event-by-event charge-separation fluctuations perpendicular to ...

  20. System-size independence of directed flow at the RelativisticHeavy-Ion Collider

    SciTech Connect (OSTI)

    STAR Coll

    2008-09-20T23:59:59.000Z

    We measure directed flow (v{sub 1}) for charged particles in Au + Au and Cu + Cu collisions at {radical}s{sub NN} = 200 GeV and 62.4 GeV, as a function of pseudorapidity ({eta}), transverse momentum (p{sub t}) and collision centrality, based on data from the STAR experiment. We find that the directed flow depends on the incident energy but, contrary to all available model implementations, not on the size of the colliding system at a given centrality. We extend the validity of the limiting fragmentation concept to v{sub 1} in different collision systems, and investigate possible explanations for the observed sign change in v{sub 1}(p{sub t}).

  1. The Relativistic Heavy Ion Collider (RHIC) cryogenic system at Brookhaven National Laboratory: Review of the modifications and upgrades since 2002 and planned improvements.

    SciTech Connect (OSTI)

    Than, R.; Tuozzolo, Joseph; Sidi-Yekhlef, Ahmed; Ganni, Venkatarao; Knudsen, Peter; Arenius, Dana

    2008-03-01T23:59:59.000Z

    Brookhaven National Laboratory continues its multi-year program to improve the operational efficiency, reliability, and stability of the cryogenic system, which also resulted in an 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, 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-Thomson ex

  2. The Electron-Ion Collider

    E-Print Network [OSTI]

    V. Guzey

    2009-07-23T23:59:59.000Z

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

  3. Bose-Einstein condensation of pions in heavy-ion collisions at the CERN Large Hadron Collider (LHC) energies

    E-Print Network [OSTI]

    Viktor Begun; Wojciech Florkowski

    2015-04-22T23:59:59.000Z

    We analyse in detail the possibility of Bose-Einstein condensation of pions produced in heavy-ion collisions at the beam energy $\\sqrt{s_{\\rm NN}}$ = 2.76 TeV. Our approach is based on the chemical non-equilibrium thermal model of hadron production which has been generalised to include separately the contribution from the local zero-momentum state. In order to study both the hadronic multiplicities and the transverse-momentum spectra, we use the Cracow freeze-out model which parameterises the flow and space-time geometry of the system at freeze-out in a very economic way. Our analysis indicates that about 5% of all pions may form the Bose-Einstein condensate.

  4. 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.

    2007-07-16T23:59:59.000Z

    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.

  5. Core - Corona Model analysis of the Low Energy Beam Scan at RHIC (Relativistic Heavy Ion Collider) in Brookhaven (USA)

    E-Print Network [OSTI]

    M. Gemard; J. Aichelin

    2014-02-02T23:59:59.000Z

    The centrality dependence of spectra of identified particles in collisions between ultrarelativistic heavy ions with a center of mass energy ($\\sqrt{s}$) of 39 and 11.5 $AGeV$ is analyzed in the core - corona model. We show that at these energies the spectra can be well understood assuming that they are composed of two components whose relative fraction depends on the centrality of the interaction: The core component which describes an equilibrated quark gluon plasma and the corona component which is caused by nucleons close to the surface of the interaction zone which scatter only once and which is identical to that observed in proton-proton collisions. The success of this approach at 39 and 11.5 $AGeV$ shows that the physics does not change between this energy and $\\sqrt{s}=200~ AGeV$ for which this model has been developed (Aichelin 2008). This presents circumstantial evidence that a quark gluon plasma is also created at center of mass energies as low as 11.5 $AGeV$.

  6. HEAVY-ION RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2010-01-01T23:59:59.000Z

    RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY 1,2 Jacob I .RADIOGRAPHY AND HEAVY-ION COMPUTED TOMOGRAPHY J I Fabrikant,

  7. Relativistic heavy ion research

    SciTech Connect (OSTI)

    Nagamiya, Shoji.

    1992-01-01T23:59:59.000Z

    This report discusses the following topics: antiproton production; Bose-Einstein correlations; high-transverse momentum spectra; strangeness enhancement in heavy ion collisions; search for rare negative secondaries of antiprotons and antinuclei produced in heavy ion collisions; quark matter; and time-of-flight systems test at Brookhaven AGS. (LSP).

  8. THE RELATIVISTIC HEAVY ION COLLIDER (RHIC) REFRIGERATOR SYSTEM AT BROOKHAVEN NATIONAL LABORATORY: PHASE III OF THE SYSTEM PERFORMANCE AND OPERATIONS UPGRADES FOR 2003

    SciTech Connect (OSTI)

    SIDI-YEKHLEF,A.; TUOZZOLO,J.; THAN, R.; KNUDSEN, P.; ARENIUS, D.

    2005-08-29T23:59:59.000Z

    An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and I1 of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase 111, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for, the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.

  9. The Relativistic Heavy Ion Collider (RHIC) Refrigerator System at Brookhaven National Laboratory: Phase III of the System Performance and Operations Upgrades for 2006

    SciTech Connect (OSTI)

    A. Sidi-Yekhlef; R. Than; J. Tuozzolo; V. Ganni; P. Knudsen; D. Arenius

    2006-05-01T23:59:59.000Z

    An ongoing program at Brookhaven National Laboratory (BNL) consists of improving the efficiency of the Relativistic Heavy Ion Collider (RHIC) cryogenic system and reducing its power consumption. Phase I and II of the program addressed plant operational improvements and modifications that resulted in substantial operational cost reduction and improved system reliability and stability, and a compressor input power reduction of 2 MW has been demonstrated. Phase III, now under way, consists of plans for further increasing the efficiency of the plant by adding a load ''wet'' turbo-expander and its associated heat exchangers at the low temperature end of the plant. This additional stage of cooling at the coldest level will further reduce the required compressor flow and therefore compressor power input. This paper presents the results of the plant characterization, as it is operating presently, as well as the results of the plant simulations of the various planned upgrades for the plant. The immediate upgrade includes the changes associated with the load expander. The subsequent upgrade will involve the resizing of expander 5 and 6 to increase their efficiencies. The paper summarizes the expected improvement in the plant efficiency and the overall reduction in the compressor power.

  10. HEAVY ION INERTIAL FUSION

    E-Print Network [OSTI]

    Keefe, D.

    2008-01-01T23:59:59.000Z

    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

  11. Toward an understanding of the single electron data measured at the BNL Relativistic Heavy Ion Collider (RHIC)

    SciTech Connect (OSTI)

    Gossiaux, P. B.; Aichelin, J. [SUBATECH, Universite de Nantes, EMN, IN2P3/CNRS, 4 rue Alfred Kastler, F-44307 Nantes cedex 3 (France)

    2008-07-15T23:59:59.000Z

    High transverse momentum (p{sub T}) single nonphotonic electrons which have been measured in the RHIC experiments come dominantly from heavy meson decay. The ratio of their p{sub T} spectra in pp and AA collisions [R{sub AA}(p{sub T})] reveals the energy loss of heavy quarks in the environment created by AA collisions. Using a fixed coupling constant and the Debye mass (m{sub D}{approx_equal}gT) as the infrared regulator, perturbative QCD (pQCD) calculations are not able to reproduce the data, neither the energy loss nor the azimuthal (v{sub 2}) distribution. Employing a running coupling constant and replacing the Debye mass by a more realistic hard thermal loop (HTL) calculation, we find a substantial increase in the collisional energy loss, which brings the v{sub 2}(p{sub T}) distribution as well as R{sub AA}(p{sub T}) to values close to the experimental ones without excluding a contribution from radiative energy loss.

  12. Charm and bottom production in inclusive double Pomeron exchange in heavy-ion collisions at energies available at the CERN Large Hadron Collider

    SciTech Connect (OSTI)

    Gay Ducati, M. B.; Machado, M. M.; Machado, M. V. T. [High Energy Physics Phenomenology Group, GFPAE, IF-UFRGS Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil)

    2011-01-15T23:59:59.000Z

    The inclusive double Pomeron exchange cross section for heavy-quark pair production is calculated for nucleus-nucleus collisions at the Large Hadron Collider. The present estimate is based on hard diffractive factorization, corrected by absorptive corrections and nuclear effects. The theoretical uncertainties for nuclear collisions are investigated and a comparison to other approaches is presented. The production channels giving a similar final state configuration are discussed as well.

  13. Heavy Ion Collisions at the LHC - Last Call for Predictions

    E-Print Network [OSTI]

    S. Abreu; S. V. Akkelin; J. Alam; J. L. Albacete; A. Andronic; D. Antonov; F. Arleo; N. Armesto; I. C. Arsene; G. G. Barnafoldi; J. Barrette; B. Bauchle; F. Becattini; B. Betz; M. Bleicher; M. Bluhm; D. Boer; F. W. Bopp; P. Braun-Munzinger; L. Bravina; W. Busza; M. Cacciari; A. Capella; J. Casalderrey-Solana; R. Chatterjee; L. -W. Chen; J. Cleymans; B. A. Cole; Z. Conesa Del Valle; L. P. Csernai; L. Cunqueiro; A. Dainese; J. Dias de Deus H. -T. Ding; M. Djordjevic; H. Drescher; I. M. Dremin A. Dumitru; A. El; R. Engel; D. d'Enterria; K. J. Eskola; G. Fai; E. G. Ferreiro; R. J. Fries; E. Frodermann; H. Fujii; C. Gale; F. Gelis; V. P. Goncalves; V. Greco; C. Greiner; M. Gyulassy; H. van Hees; U. Heinz; H. Honkanen; W. A. Horowitz; E. Iancu; G. Ingelman; J. Jalilian-Marian; S. Jeon; A. B. Kaidalov; B. Kampfer; Z. -B. Kang; Iu. A. Karpenko; G. Kestin; D. Kharzeev; C. M. Ko; B. Koch; B. Kopeliovich; M. Kozlov; I. Kraus; I. Kuznetsova; S. H. Lee; R. Lednicky; J. Letessier; E. Levin; B. -A. Li; Z. -W. Lin; H. Liu; W. Liu; C. Loizides; I. P. Lokhtin; M. V. T. Machado; L. V. Malinina; A. M. Managadze; M. L. Mangano; M. Mannarelli; C. Manuel; G. Martinez; J. G. Milhano; A. Mocsy; D. Molnar; M. Nardi; J. K. Nayak; H. Niemi; H. Oeschler; J. -Y. Ollitrault; G. Paic; C. Pajares; V. S. Pantuev; G. Papp; D. Peressounko; P. Petreczky; S. V. Petrushanko; F. Piccinini; T. Pierog; H. J. Pirner; S. Porteboeuf; I. Potashnikova; G. Y. Qin; J. -W. Qiu; J. Rafelski; K. Rajagopal; J. Ranft; R. Rapp; S. S. Rasanen; J. Rathsman; P. Rau; K. Redlich; T. Renk; A. H. Rezaeian; D. Rischke; S. Roesler; J. Ruppert; P. V. Ruuskanen; C. A. Salgado; S. Sapeta; I. Sarcevic; S. Sarkar; L. I. Sarycheva; I. Schmidt; A. I. Shoshi; B. Sinha; Yu. M. Sinyukov; A. M. Snigirev; D. K. Srivastava; J. Stachel; A. Stasto; H. Stocker; C. Yu. Teplov; R. L. Thews; G. Torrieri; V. Topor Pop; D. N. Triantafyllopoulos; K. L. Tuchin; S. Turbide; K. Tywoniuk; A. Utermann; R. Venugopalan; I. Vitev; R. Vogt; E. Wang; X. N. Wang; K. Werner; E. Wessels; S. Wheaton; S. Wicks; U. A. Wiedemann; G. Wolschin; B. -W. Xiao; Z. Xu; S. Yasui; E. Zabrodin; K. Zapp; B. Zhang; B. -W. Zhang; H. Zhang; D. Zhou

    2007-11-06T23:59:59.000Z

    This writeup is a compilation of the predictions for the forthcoming Heavy Ion Program at the Large Hadron Collider, as presented at the CERN Theory Institute 'Heavy Ion Collisions at the LHC - Last Call for Predictions', held from May 14th to June 10th 2007.

  14. RHIC | Relativistic Heavy Ion Collider

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

    CERN logo U.S.-CERN Agreement Paves Way for New Era of Scientific Discovery A new agreement between the United States and the European Organization for Nuclear Research (CERN)...

  15. Jet Analysis in Heavy Ion Collisions in CMS

    E-Print Network [OSTI]

    M. B. Tonjes; for the CMS collaboration

    2008-10-17T23:59:59.000Z

    At the Relativistic Heavy Ion Collider, jets have been a useful tool to probe the properties of the hot, dense matter created. At the Large Hadron Collider, collisions of Pb+Pb at $\\sqrt{s_{NN}}$ = 5.5 TeV will provide a large cross section of jets at high $E_T$ above the minimum bias heavy ion background. Simulations of the Compact Muon Solenoid (CMS) experiment's capability to measure jets in heavy ion collisions are presented. In particular, $\\gamma$-jet measurements can estimate the amount of energy lost by a jet interacting strongly with the medium, since the tagged photon passes through unaffected.

  16. RHIC | Electron-Ion Collider

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

    is a ripple, the product of those pre-smash particles flying at relativistic speeds. By examining accelerated ions directly, scientists might clearly identify physics phenomena...

  17. Acceleration of heavy ions in the AGS and CBA

    SciTech Connect (OSTI)

    Barton, M.Q.

    1983-01-01T23:59:59.000Z

    A plan has been developed to inject ion beams from the Brookhaven Tandem or a cyclotron added to the Tandem into the AGS. This beam could then be injected into a relativistic heavy ion collider. The availability of many CBA components adds to the attractiveness of this proposal.

  18. Prospects of Heavy Neutrino Searches at Future Lepton Colliders

    E-Print Network [OSTI]

    Banerjee, Shankha; Ibarra, Alejandro; Mandal, Tanumoy; Mitra, Manimala

    2015-01-01T23:59:59.000Z

    We discuss the future prospects of heavy neutrino searches at next generation lepton colliders. In particular, we focus on the planned electron-positron colliders, operating in two different beam modes, namely, $e^+e^-$ and $e^-e^-$. In the $e^+e^-$ beam mode, we consider various production and decay modes of the heavy neutrino ($N$), and find that the final state with $e+2j+\\slashed{E}$, arising from the $e^+e^-\\to N\

  19. Heavy Ion Event Displays

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

    simulated collisions of lead ions in the LHC experiments. Additional photos, video and information are available at these links: Lead-ion collision images from the ALICE...

  20. Damage Profile and Ion Distribution of Slow Heavy Ions in Compounds...

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

    Profile and Ion Distribution of Slow Heavy Ions in Compounds. Damage Profile and Ion Distribution of Slow Heavy Ions in Compounds. Abstract: Slow heavy ions inevitably produce a...

  1. Elliptic flow and energy loss of heavy quarks in ultrarelativistic heavy ion collisions

    SciTech Connect (OSTI)

    Uphoff, Jan; Fochler, Oliver; Greiner, Carsten [Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet Frankfurt, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main (Germany); Xu, Zhe [Institut fuer Theoretische Physik, Johann Wolfgang Goethe-Universitaet Frankfurt, Max-von-Laue-Strasse 1, D-60438 Frankfurt am Main (Germany); Frankfurt Institute for Advanced Studies, Ruth-Moufang-Strasse 1, D-60438 Frankfurt am Main (Germany)

    2011-08-15T23:59:59.000Z

    The space-time propagation of heavy quarks in ultrarelativistic heavy ion collisions is studied within the partonic transport model Boltzmann approach of multiparton scatterings (BAMPS). In this model heavy quarks interact with the partonic medium via binary scatterings. The cross sections for these interactions are calculated with leading-order perturbative QCD, but feature a more precise Debye screening derived within the hard thermal loop approximation and obey the running of the coupling. Within this framework the elliptic flow and the nuclear modification factor of heavy quarks are computed for the BNL Relativistic Heavy Ion Collider (RHIC) and the CERN Large Hadron Collider (LHC) energies and compared to available experimental data. It is found that binary scatterings alone cannot reproduce the data and therefore radiative corrections have to be taken into account.

  2. INTERACTION REGION DESIGN FOR THE ELECTRON-ION COLLIDER ERHIC.

    SciTech Connect (OSTI)

    MONTAG, C.; PARKER, B.; TEPIKIAN, S.; ET AL.

    2005-05-16T23:59:59.000Z

    To facilitate the study of collisions between 10 GeV polarized electrons and 100 GeV/u heavy ions or 250 GeV polarized protons at luminosities in the 10{sup 33} cm{sup -2} sec{sup -1} range (e-p case), adding a 10 GeV electron storage ring to the existing RHIC complex has been proposed. The interaction region of this electron-ion collider eRHIC has to provide the required low-beta focusing, while simultaneously accommodating the synchrotron radiation fan generated by beam separation close to the interaction point, which is particularly challenging. The latest design status of the eRHIC interaction region will be presented.

  3. Chemistry of heavy ion reactions

    SciTech Connect (OSTI)

    Hoffman, D.C.

    1988-10-01T23:59:59.000Z

    The use of heavy ions to induce nuclear reactions was reported as early as 1950. Since that time it has been one of the most active areas of nuclear research. Intense beams of ions as heavy as uranium with energies high enough to overcome the Coulomb barriers of even the heaviest elements are available. The wide variety of possible reactions gives rise to a multitude of products which have been studied by many ingenious chemical and physical techniques. Chemical techniques have been of special value for the separation and unequivocal identification of low yield species from the plethora of other nuclides present. Heavy ion reactions have been essential for the production of the trans-Md elements and a host of new isotopes. The systematics of compound nucleus reactions, transfer reactions, and deeply inelastic reactions have been elucidated using chemical techniques. A review of the variety of chemical procedures and techniques which have been developed for the study of heavy ion reactions and their products is given. Determination of the chemical properties of the trans-Md elements, which are very short-lived and can only be produced an ''atom-at-a-time'' via heavy ion reactions, is discussed. 53 refs., 19 figs.

  4. Pionic Fusion of Heavy Ions

    E-Print Network [OSTI]

    D. Horn; G. C. Ball; D. R. Bowman; W. G. Davies; D. Fox; A. Galindo-Uribarri; A. C. Hayes; G. Savard; L. Beaulieu; Y. Larochelle; C. St-Pierre

    1996-08-13T23:59:59.000Z

    We report the first experimental observation of the pionic fusion of two heavy ions. The 12C(12C,24Mg)pi0 and 12C(12C,24Na)pi+ cross sections have been measured to be 208 +/- 38 and 182 +/- 84 picobarns, respectively, at E_cm = 137 MeV. This cross section for heavy-ion pion production, at an energy just 6 MeV above the absolute energy-conservation limit, constrains possible production mechanisms to incorporate the kinetic energy of the entire projectile-target system as well as the binding energy gained in fusion.

  5. Production of e(+)e(-) pairs accompanied by nuclear dissociation in ultraperipheral heavy-ion collisions

    E-Print Network [OSTI]

    Adams, J.; Aggarwal, MM; Ahammed, Z.; Amonett, J.; Anderson, BD; Arkhipkin, D.; Averichev, GS; Bai, Y.; Balewski, J.; Barannikova, O.; Barnby, LS; Baudot, J.; Bekele, S.; Belaga, VV; Bellwied, R.; Berger, J.; Bezverkhny, BI; Bharadwaj, S.; Bhatia, VS; Bichsel, H.; Billmeier, A.; Bland, LC; Blyth, CO; Bonner, BE; Botje, M.; Boucham, A.; Brandin, A.; Bravar, A.; Bystersky, M.; Cadman, RV; Cai, XZ; Caines, H.; Sanchez, MCD; Carroll, J.; Castillo, J.; Cebra, D.; Chajecki, Z.; Chaloupka, P.; Chattopdhyay, S.; Chen, HF; Chen, Y.; Cheng, J.; Cherney, M.; Chikanian, A.; Christie, W.; Coffin, JP; Cormier, TM; Cramer, JG; Crawford, HJ; Das, D.; Das, S.; de Moura, MM; Derevschikov, AA; Didenko, L.; Dietel, T.; Dong, WJ; Dong, X.; Draper, JE; Du, F.; Dubey, AK; Dunin, VB; Dunlop, JC; Mazumdar, MRD; Eckardt, V.; Edwards, WR; Efimov, LG; Emelianov, V.; Engelage, J.; Eppley, G.; Erazmus, B.; Estienne, M.; Fachini, P.; Faivre, J.; Fatemi, R.; Fedorisin, J.; Filimonov, K.; Filip, P.; Finch, E.; Fine, V.; Fisyak, Y.; Foley, KJ; Fomenko, K.; Fu, J.; Gagliardi, Carl A.; Gans, J.; Ganti, MS; Gaudichet, L.; Geurts, F.; Ghazikhanian, V.; Ghosh, P.; Gonzalez, JE; Grachov, O.; Grebenyuk, O.; Grosnick, D.; Guertin, SM; Guo, Y.; Gupta, A.; Gutierrez, TD; Hallman, TJ; Hamed, A.; Hardtke, D.; Harris, JW; Heinz, M.; Henry, TW; Hepplemann, S.; Hippolyte, B.; Hirsch, A.; Hjort, E.; Hoffmann, GW; Huang, HZ; Huang, SL; Hughes, EW; Humanic, TJ; Igo, G.; Ishihara, A.; Jacobs, P.; Jacobs, WW; Janik, M.; Jiang, H.; Jones, PG; Judd, EG; Kabana, S.; Kang, K.; Kaplan, M.; Keane, D.; Khodyrev, VY; Kiryluk, J.; Kisiel, A.; Kislov, EM; Klay, J.; Klein, SR; Klyachko, A.; Koetke, DD; Kollegger, T.; Kopytine, M.; Kotchenda, L.; Kramer, M.; Kravtsov, P.; Kravtsov, VI; Krueger, K.; Kuhn, C.; Kulikov, AI; Kumar, A.; Kunz, CL; Kutuev, RK; Kuznetsov, AA; Lamont, MAC; Landgraf, JM; Lange, S.; Laue, F.; Lauret, J.; Lebedev, A.; Lednicky, R.; Lehocka, S.; LeVine, MJ; Li, C.; Li, Q.; Li, Y.; Lindenbaum, SJ; Lisa, MA; Liu, F.; Liu, L.; Liu, QJ; Liu, Z.; Ljubicic, T.; Llope, WJ; Long, H.; Longacre, RS; Lopez-Noriega, M.; Love, WA; Lu, Y.; Ludlam, T.; Lynn, D.; Ma, GL; Ma, JG; Ma, YG; Magestro, D.; Mahajan, S.; Mahapatra, DP; Majka, R.; Mangotra, LK; Manweiler, R.; Margetis, S.; Markert, C.; Martin, L.; Marx, JN; Matis, HS; Matulenko, YA; McClain, CJ; McShane, TS; Meissner, F.; Melnick, Y.; Meschanin, A.; Miller, ML; Milosevich, Z.; Minaev, NG; Mironov, C.; Mischke, A.; Mishra, D.; Mitchell, J.; Mohanty, B.; Molnar, L.; Moore, CF; Mora-Corral, MJ; Morozov, DA; Morozov, V.; Munhoz, MG; Nandi, BK; Nayak, TK; Nelson, JM; Netrakanti, PK; Nikitin, VA; Nogach, LV; Norman, B.; Nurushev, SB; Odyniec, G.; Ogawa, A.; Okorokov, V.; Oldenburg, M.; Olson, D.; Pal, SK; Panebratsev, Y.; Panitkin, SY; Pavlinov, AI; Pawlak, T.; Peitzmann, T.; Perevoztchikov, V.; Perkins, C.; Peryt, W.; Petrov, VA; Phatak, SC; Picha, R.; Planinic, M.; Pluta, J.; Porile, N.; Porter, J.; Poskanzer, AM; Potekhin, M.; Potrebenikova, E.; Potukuchi, BVKS; Prindle, D.; Pruneau, C.; Putschke, J.; Rai, G.; Rakness, G.; Raniwala, R.; Raniwala, S.; Ravel, O.; Ray, RL; Razin, SV; Reichhold, D.; Reid, JG; Renault, G.; Retiere, F.; Ridiger, A.; Ritter, HG; Roberts, JB; Rogachevskiy, OV; Romero, JL; Rose, A.; Roy, C.; Ruan, L.; Sakrejda, I.; Salur, S.; Sandweiss, J.; Savin, I.; Sazhin, PS; Schambach, J.; Scharenberg, RP; Schmitz, N.; Schroeder, LS; Schweda, K.; Seger, J.; Seyboth, P.; Shahaliev, E.; Shao, M.; Shao, W.; Sharma, M.; Shen, WQ; Shestermanov, KE; Shimanskiy, SS; Simon, F.; Singaraju, RN; Skoro, G.; Smirnov, N.; Snellings, R.; Sood, G.; Sorensen, P.; Sowinski, J.; Speltz, J.; Spinka, H. M.; Srivastava, B.; Stadnik, A.; Stanislaus, TDS; Stock, R.; Stolpovsky, A.; Strikhanov, M.; Stringfellow, B.; Suaide, AAP; Sugarbaker, E.; Suire, C.; Sumbera, M.; Surrow, B.; Symons, TJM; de Toledo, AS; Szarwas, P.; Tai, A.; Takahashi, J.; Tang, AH; Tarnowsky, T.; Thein, D.; Thomas, JH; Timoshenko, S.; Tokarev, M.; Trainor, TA; Trentalange, S.; Tribble, Robert E.; Tsai, O.; Ulery, J.; Ullrich, T.; Underwood, DG; Urkinbaev, A.; Buren, GV; van Leeuwen, M.; Vander Molen, AM; Varma, R.; Vasilevski, IM; Vasiliev, AN; Vernet, R.; Vigdor, SE; Viyogi, VP; Vokal, S.; Voloshin, SA; Vznuzdaev, M.; Waggoner, B.; Wang, F.; Wang, G.; Wang, G.; Wang, XL; Wang, Y.; Wang, Y.; Wang, ZM; Ward, H.; Watson, JW; Webb, JC; Wells, R.; Westfall, GD; Wetzler, A.; Whitten, C.; Wieman, H.; Wissink, SW; Witt, R.; Wood, J.; Wu, J.; Xu, N.; Xu, Z.; Xu, ZZ; Yamamoto, E.; Yepes, P.; Yurevich, VI; Zanevsky, YV; Zhang, H.; Zhang, WM; Zhang, ZP; Zolnierczuk, PA; Zoulkarneev, R.; Zoulkarneeva, Y.; Zubarev, AN; STAR Collaboration.

    2004-01-01T23:59:59.000Z

    Tracker at the RHIC (STAR) detector at the Relativ- istic Heavy Ion Collider (RHIC). Tracks were reconstructed in a large cylindrical time projection chamber (TPC) [24] embedded in a solenoidal magnetic field. The track position and specific energy...

  6. Title Quantum Optics and Heavy Ion Physics

    E-Print Network [OSTI]

    Roy J. Glauber

    2006-04-10T23:59:59.000Z

    I shall try to say a few words about two particular ways in which my own work has a certain relation to your work with heavy ions. My title is therefore "Quantum Optics and Heavy Ion Physics".

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

    E-Print Network [OSTI]

    ShinIchi Esumi

    2004-05-19T23:59:59.000Z

    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.

  8. Molecular dynamics simulations of ion range profiles for heavy...

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

    simulations of ion range profiles for heavy ions in light targets. Molecular dynamics simulations of ion range profiles for heavy ions in light targets. Abstract: The determination...

  9. Core-Corona Separation in Ultrarelativistic Heavy Ion Collisions

    SciTech Connect (OSTI)

    Werner, Klaus [SUBATECH, University of Nantes-IN2P3/CNRS-EMN, Nantes 44000 (France)

    2007-04-13T23:59:59.000Z

    Simple geometrical considerations show that the collision zone in high energy nuclear collisions may be divided into a central part ('core'), with high energy densities, and a peripheral part ('corona'), with smaller energy densities, more like in pp or pA collisions. We present calculations that allow us to separate these two contributions, and which show that the corona contribution is quite small (but not negligible) for central collisions, but gets increasingly important with decreasing centrality. We will discuss consequences concerning results obtained in heavy ion collisions at the BNL Relativistic Heavy Ion Collider and CERN Super Proton Synchrotron.

  10. Collective Phenomena in Heavy Ion Collisions

    E-Print Network [OSTI]

    M. Petrovici; A. Pop

    2009-04-23T23:59:59.000Z

    A review of the main results of detailed flow analysis in highly central and semi-central heavy ion collisions at SIS energies is presented in the first part of this paper. The influence of the mass of the colliding nuclei and centrality on the collective expansion and the information on the equation of state of compressed and hot baryonic matter is discussed. The second part is dedicated to a similar type of analysis, based on the behaviour of the average transverse momentum as a function of mass of different hadrons, at the other extreme of energy range, where free baryonic fireballs are produced. Information on the partonic and hadronic expansion, temperature and degree of thermal equilibrium in p+p and Au+Au central collisions at 200 A.GeV is presented.

  11. The Heavy Ion Fusion Virtual National Laboratory The Heavy Ion Path to Fusion Energy

    E-Print Network [OSTI]

    , describes R&D needs for heavy-ion accelerator, target and chamber R&D. 44 pages. Defines goals and criteria tasks) - ion accelerator technologies - chamber and maintenance technologies - pulsed power technologiesThe Heavy Ion Fusion Virtual National Laboratory The Heavy Ion Path to Fusion Energy Grant Logan

  12. SECTION II. HEAVY ION REACTIONS

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection245C Unlimited Release PrintedDEVIATIONS F O INTERACTIONSII. HEAVY ION

  13. Relativistic Heavy Ion Collider Funding Agencies

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

    Commission of France ARMINES (France) Federal Ministry of Education and Research of Germany German Academic Exchange Service Alexander von Humboldt Foundation, Germany National...

  14. Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    line- of-sight damage from target debris, neutron and gamma radiation. · Target injection: Heavy ions-liquid-protected target chambers with 30 yr lifetimes. · Robust final optics: Focusing magnets for ion beams avoid direct

  15. Colliding Nuclei at High Energy

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08T23:59:59.000Z

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

  16. Relativistic heavy ion research. Progress report

    SciTech Connect (OSTI)

    Nagamiya, Shoji

    1992-07-01T23:59:59.000Z

    This report discusses the following topics: antiproton production; Bose-Einstein correlations; high-transverse momentum spectra; strangeness enhancement in heavy ion collisions; search for rare negative secondaries of antiprotons and antinuclei produced in heavy ion collisions; quark matter; and time-of-flight systems test at Brookhaven AGS. (LSP).

  17. Heavy ion, recirculating linac, design optimization

    SciTech Connect (OSTI)

    Hewett, D.W. (Lawrence Livermore National Lab., CA (United States)); Godlove, T.F. (FM Technologies, Inc., Fairfax Station, VA (United States))

    1991-06-04T23:59:59.000Z

    Cost optimization is important to the development of high-current, heavy-ion accelerators for power production based on inertial confinement fusion. Two heavy-ion, recirculating linac configurations are examined that eliminate the necessity to provide reset pulses for the cores used in the linac induction accelerating modules. 3 refs., 2 figs.

  18. Simulation of chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Simulation of Chamber Transport for Heavy-Ion Fusion W. M.et al. , “Modeling Chamber Transport for Heavy-Ion Fusion,”et al. , "Chamber Transport of `Foot' Pulses for Heavy-Ion

  19. Pre-Town Meeting on Spin Physics at an Electron-Ion Collider

    E-Print Network [OSTI]

    Elke-Caroline Aschenauer; Ian Balitsky; Leslie Bland; Stanley J. Brodsky; Matthias Burkardt; Volker Burkert; Jian-Ping Chen; Abhay Deshpande; Markus Diehl; Leonard Gamberg; Matthias Grosse Perdekamp; Jin Huang; Charles Hyde; Xiangdong Ji; Xiaodong Jiang; Zhong-Bo Kang; Valery Kubarovsky; John Lajoie; Keh-Fei Liu; Ming Liu; Simonetta Liuti; Wally Melnitchouk; Piet Mulders; Alexei Prokudin; Andrey Tarasov; Jian-Wei Qiu; Anatoly Radyushkin; David Richards; Ernst Sichtermann; Marco Stratmann; Werner Vogelsang; Feng Yuan

    2014-10-31T23:59:59.000Z

    A polarized $ep/eA$ collider (Electron--Ion Collider, or EIC), with polarized proton and light-ion beams and unpolarized heavy-ion beams with a variable center--of--mass energy $\\sqrt{s} \\sim 20$ to $\\sim100$~GeV (upgradable to $\\sim 150$ GeV) and a luminosity up to $\\sim 10^{34} \\, \\textrm{cm}^{-2} \\textrm{s}^{-1}$, would be uniquely suited to address several outstanding questions of Quantum Chromodynamics, and thereby lead to new qualitative and quantitative information on the microscopic structure of hadrons and nuclei. During this meeting at Jefferson Lab we addressed recent theoretical and experimental developments in the spin and the three--dimensional structure of the nucleon (sea quark and gluon spatial distributions, orbital motion, polarization, and their correlations). This mini--review contains a short update on progress in these areas since the EIC White paper~\\cite{Accardi:2012qut}.

  20. D-sJ(2317) meson production in ultrarelativistic heavy ion collisions RID A-2398-2009

    E-Print Network [OSTI]

    Chen, L. W.; Ko, Che Ming; Liu, W.; Nielsen, M.

    2007-01-01T23:59:59.000Z

    Production of D-sJ(2317) mesons in relativistic heavy ion collisions at the BNL Relativistic Heavy Ion Collider is studied. Using the quark coalescence model, we first determine the initial number of D-sJ(2317) mesons produced during hadronization...

  1. Long Plasma Source for Heavy Ion Beam Charge Neutralization

    E-Print Network [OSTI]

    Efthimion, P.C.

    2009-01-01T23:59:59.000Z

    neutralizing plasma column the heavy ion beam can focus to aPlasmas are a source of unbound electrons for charge neutralizing intense heavy ion beams to focus

  2. Collider searches and cosmology in the MSSM with heavy scalars

    SciTech Connect (OSTI)

    Carena, Marcela; /Fermilab; Freitas, A.; /Zurich U.

    2006-08-01T23:59:59.000Z

    In a variety of supersymmetric extensions of the Standard Model, the scalar partners of the quarks and leptons are predicted to be very heavy and beyond the reach of next-generation colliders. For instance, the realization of electroweak baryogenesis in supersymmetry requires new sources of CP-violation, which can only be naturally accommodated with electric dipole moment constraints if the first and second generation scalar fermions are beyond the TeV scale. Also in focus-point supersymmetry and split supersymmetry the scalar fermions are very heavy. In this work, the phenomenology of scenarios with electroweak baryogenesis and in the focus point region at the LHC and ILC is studied, which becomes challenging due to the presence of heavy scalar fermions. Implications for the analysis of baryogenesis and dark matter are deduced. It is found that precision measurements of superpartner properties allow an accurate determination of the dark matter relic density in both scenarios, while important but only incomplete information about the baryogenesis mechanism can be obtained.

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

    SciTech Connect (OSTI)

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

    2012-08-01T23:59:59.000Z

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

  4. Heavy Ion Collisions at the LHC - Last Call for Predictions

    SciTech Connect (OSTI)

    Armesto, N; Borghini, N; Jeon, S; Wiedemann, U A; Abreu, S; Akkelin, V; Alam, J; Albacete, J L; Andronic, A; Antonuv, D; Arleo, F; Armesto, N; Arsene, I C; Barnafoldi, G G; Barrette, J; Bauchle, B; Becattini, F; Betz, B; Bleicher, M; Bluhm, M; Boer, D; Bopp, F W; Braun-Munzinger, P; Bravina, L; Busza, W; Cacciari, M; Capella, A; Casalderrey-Solana, J; Chatterjee, R; Chen, L; Cleymans, J; Cole, B A; delValle, Z C; Csernai, L P; Cunqueiro, L; Dainese, A; de Deus, J D; Ding, H; Djordjevic, M; Drescher, H; Dremin, I M; Dumitru, A; El, A; Engel, R; d'Enterria, D; Eskola, K J; Fai, G; Ferreiro, E G; Fries, R J; Frodermann, E; Fujii, H; Gale, C; Gelis, F; Goncalves, V P; Greco, V; Gyulassy, M; van Hees, H; Heinz, U; Honkanen, H; Horowitz, W A; Iancu, E; Ingelman, G; Jalilian-Marian, J; Jeon, S; Kaidalov, A B; Kampfer, B; Kang, Z; Karpenko, I A; Kestin, G; Kharzeev, D; Ko, C M; Koch, B; Kopeliovich, B; Kozlov, M; Kraus, I; Kuznetsova, I; Lee, S H; Lednicky, R; Letessier, J; Levin, E; Li, B; Lin, Z; Liu, H; Liu, W; Loizides, C; Lokhtin, I P; Machado, M T; Malinina, L V; Managadze, A M; Mangano, M L; Mannarelli, M; Manuel, C; Martinez, G; Milhano, J G; Mocsy, A; Molnar, D; Nardi, M; Nayak, J K; Niemi, H; Oeschler, H; Ollitrault, J; Paic, G; Pajares, C; Pantuev, V S; Papp, G; Peressounko, D; Petreczky, P; Petrushanko, S V; Piccinini, F; Pierog, T; Pirner, H J; Porteboeuf, S; Potashnikova, I; Qin, G Y; Qiu, J; Rafelski, J; Rajagopal, K; Ranft, J; Rapp, R; Rasanen, S S; Rathsman, J; Rau, P; Redlich, K; Renk, T; Rezaeian, A H; Rischke, D; Roesler, S; Ruppert, J; Ruuskanen, P V; Salgado, C A; Sapeta, S; Sarcevic, I; Sarkar, S; Sarycheva, L I; Schmidt, I; Shoski, A I; Sinha, B; Sinyukov, Y M; Snigirev, A M; Srivastava, D K; Stachel, J; Stasto, A; Stocker, H; Teplov, C Y; Thews, R L; Torrieri, G; Pop, V T; Triantafyllopoulos, D N; Tuchin, K L; Turbide, S; Tywoniuk, K; Utermann, A; Venugopalan, R; Vitev, I; Vogt, R; Wang, E; Wang, X N; Werner, K; Wessels, E; Wheaton, S; Wicks, S; Wiedemann, U A; Wolschin, G; Xiao, B; Xu, Z; Yasui, S; Zabrodin, E; Zapp, K; Zhang, B

    2008-02-25T23:59:59.000Z

    In August 2006, the CERN Theory Unit announced to restructure its visitor program and to create a 'CERN Theory Institute', where 1-3 month long specific programs can take place. The first such Institute was held from 14 May to 10 June 2007, focusing on 'Heavy Ion Collisions at the LHC - Last Call for Predictions'. It brought together close to 100 scientists working on the theory of ultra-relativistic heavy ion collisions. The aim of this workshop was to review and document the status of expectations and predictions for the heavy ion program at the Large Hadron Collider LHC before its start. LHC will explore heavy ion collisions at {approx} 30 times higher center of mass energy than explored previously at the Relativistic Heavy Ion Collider RHIC. So, on the one hand, the charge of this workshop provided a natural forum for the exchange of the most recent ideas, and allowed to monitor how the understanding of heavy ion collisions has evolved in recent years with the data from RHIC, and with the preparation of the LHC experimental program. On the other hand, the workshop aimed at a documentation which helps to distinguish pre- from post-dictions. An analogous documentation of the 'Last Call for Predictions' [1] was prepared prior to the start of the heavy-ion program at the Relativistic Heavy Ion Collider RHIC, and it proved useful in the subsequent discussion and interpretation of RHIC data. The present write-up is the documentation of predictions for the LHC heavy ion program, received or presented during the CERN TH Institute. The set-up of the CERN TH Institute allowed us to aim for the wide-most coverage of predictions. There were more than 100 presentations and discussions during the workshop. Moreover, those unable to attend could still participate by submitting predictions in written form during the workshop. This followed the spirit that everybody interested in making a prediction had the right to be heard. To arrive at a concise document, we required that each prediction should be summarized on at most two pages, and that predictions should be presented, whenever possible, in figures which display measurable quantities. Full model descriptions were not accepted--the authors were encouraged to indicate the relevant references for the interested reader. Participants had the possibility to submit multiple contributions on different topics, but it was part of the subsequent editing process to ensure that predictions on neighboring topics were merged wherever possible. The contributions summarized here are organized in several sections,--though some of them contain material related with more than one section--roughly by going from low transverse momentum to high transverse momentum and from abundant to rare measurements. In the low transverse momentum regime, we start with predictions on multiplicity distributions, azimuthal asymmetries in particle production and hadronic flavor observables, followed by correlation and fluctuation measurements. The contributions on hard probes at the LHC start with predictions for single inclusive high transverse momentum spectra, and jets, followed by heavy quark and quarkonium measurements, leptonic probes and photons. A final section 'Others' encompasses those predictions which do not fall naturally within one of the above-mentioned categories, or discuss the more speculative phenomena that may be explored at the LHC.

  5. Jet Quenching in Heavy-Ion Collisions - The Transition Era from RHIC to LHC

    E-Print Network [OSTI]

    Barbara Betz

    2012-11-26T23:59:59.000Z

    A status report on the jet quenching physics in heavy-ion collisions is given as it appears after more than 10 years of collecting and analysing data at the Relativistic Heavy Ion Collider (RHIC) and ~1.5 years of physics at the Large Hadron Collider (LHC). The (theoretical) predictions and expectations before the start of the LHC program are contrasted with the most recent experimental results, focussing on the nuclear modification factor R_{AA}, the elliptic flow v_2 of high-p_T particles, and on the problem of initial conditions.

  6. Partonic coalescence in relativistic heavy ion collisions

    E-Print Network [OSTI]

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

    2003-01-01T23:59:59.000Z

    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...

  7. Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    progress with more modest near-term budgets. #12;Slide 5 Heavy Ion Fusion Science Virtual National requirement: modest growth of HIFS-VNL budget from present 7.7 M$/yr to ~16M$/yr, including suppo

  8. Hadron Production in Heavy Ion Collisions

    E-Print Network [OSTI]

    Helmut Oeschler; Hans Georg Ritter; Nu Xu

    2009-08-12T23:59:59.000Z

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

  9. Jets in relativistic heavy ion collisions

    SciTech Connect (OSTI)

    Wang, Xin-Nian; Gyulassy, M.

    1990-09-01T23:59:59.000Z

    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.

  10. Probing the Symmetry Energy with Heavy Ions

    E-Print Network [OSTI]

    W. G. Lynch; M. B. Tsang; Y. Zhang; P. Danielewicz; M. Famiano; Z. Li; A. W. Steiner

    2009-01-05T23:59:59.000Z

    Constraints on the EoS for symmetric matter (equal neutron and proton numbers) at supra-saturation densities have been extracted from energetic collisions of heavy ions. Collisions of neutron-deficient and neutron-rich heavy ions now provide initial constraints on the EoS of neutron-rich matter at sub-saturation densities. Comparisons are made to other available constraints.

  11. Multiphase transport model for relativistic heavy ion collisions 

    E-Print Network [OSTI]

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

    2005-01-01T23:59:59.000Z

    that for producing a plasma of deconfined quarks and gluons, which is believed to have existed during the first microsecond after the Big Bang. Experiments at the BNL Relativistic Heavy Ion Collider (RHIC) with center-of-mass energy up to ?sNN = 200 GeV in Au... will have an even higher temperature and a nearly vanishing net baryon chemical potential. Many observables have beenmeasured at RHIC, such as the rapidity distributions of various particles and their transverse momentum spectra up to very high...

  12. Chamber transport of "foot" pulses for heavy-ion fusion

    E-Print Network [OSTI]

    Sharp, W.M.; Callahan-Miller, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.

    2002-01-01T23:59:59.000Z

    Neutralization on Heavy-Ion-Fusion Chamber Transport," to beChamber transport of "foot" pulses for heavy-ion fusion W.chamber-transport effectiveness is the fraction of enclosed beam ions

  13. Production of heavy flavor and photons on high-energy colliders, and rare decays of heavy mesons

    E-Print Network [OSTI]

    Production of heavy flavor and photons on high-energy colliders, and rare decays of heavy mesons (FCNC) decay ¯B0 ¯K0 e+ e- K- + e+ e-. Prompt photon production in pp (p¯p) collisions. Production measurement of photon polarization is difficult, therefore one can instead use virtual-photon production b

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

    E-Print Network [OSTI]

    Enrique Ruiz Arriola; Wojciech Broniowski

    2014-11-21T23:59:59.000Z

    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.

  15. Jet and Leading Hadron Production in High-energy Heavy-ion Collisions

    E-Print Network [OSTI]

    Xin-Nian Wang

    2005-10-31T23:59:59.000Z

    Jet tomography has become a powerful tool for the study of properties of dense matter in high-energy heavy-ion collisions. I will discuss recent progresses in the phenomenological study of jet quenching, including momentum, colliding energy and nuclear size dependence of single hadron suppression, modification of dihadron correlations and the soft hadron distribution associated with a quenched jet.

  16. THE ELECTRON ION COLLIDER. A HIGH LUMINOSITY PROBE OF THE PARTONIC SUBSTRUCTURE OF NUCLEONS AND NUCLEI.

    SciTech Connect (OSTI)

    EDITED BY M.S. DAVIS

    2002-02-01T23:59:59.000Z

    By the end of this decade, the advancement of current and planned research into the fundamental structure of matter will require a new facility, the Electron Ion Collider (EIC). The EIC will collide high-energy beams of polarized electrons from polarized protons and neutrons, and unpolarized beams of electrons off atomic nuclei with unprecedented intensity. Research at the EIC will lead to a detailed understanding of the structure of the proton, neutron, and atomic nuclei as described by Quantum Chromo-Dynamics (QCD), the accepted theory of the strong interaction. The EIC will establish quantitative answers to important questions by delivering dramatically increased precision over existing and planned experiments and by providing completely new experimental capabilities. Indeed, the EIC will probe QCD in a manner not possible previously. This document presents the scientific case for the design, construction and operation of the EIC. While realization of the EIC requires a significant advance in the development of efficient means of producing powerful beams of energetic electrons, an important consideration for choosing the site of the EIC is the planned upgrade to the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory. The upgrade planned for RHIC will fully meet the requirements for the ion beam for the EIC, providing a distinct advantage in terms of cost, schedule and the final operation.

  17. Impact of beam transport method on chamber and driver design for heavy ion inertial fusion energy

    E-Print Network [OSTI]

    Rose, D.V.; Welch, D.R.; Olson, C.L.; Yu, S.S.; Neff, S.; Sharp, W.M.

    2002-01-01T23:59:59.000Z

    neutralization on heavy-ion fusion chamber transport,” totechniques for heavy ion fusion chamber transport,” Nucl.liquid heavy-ion fusion target chambers,” Fusion Technol.

  18. ? Production in Heavy Ion Collisions at LHC

    E-Print Network [OSTI]

    Kai Zhou; Nu Xu; Pengfei Zhuang

    2014-08-19T23:59:59.000Z

    We investigate the {\\Upsilon} production in heavy ion collisions at LHC energy in the frame of a dynamical transport approach. Both the initial production and in-medium regeneration and both the cold and hot nuclear matter effects are included in the calculations. In comparison with the ground state {\\Upsilon}(1s), the excited state {\\Upsilon}(2s) is much more sensitive to the heavy quark potential at finite temperature.

  19. Full Jet Reconstruction in Heavy Ion Collisions

    E-Print Network [OSTI]

    Sevil Salur

    2009-09-16T23:59:59.000Z

    Full jet reconstruction has traditionally been thought to be difficult in heavy ion events due to large multiplicity backgrounds. The search for new physics in high luminosity p+p collisions at the LHC similarly requires the precise measurement of jets over large backgrounds caused by pile up; this has motivated the development of a new generation of jet reconstruction algorithms which are also applicable in the heavy ion environment. We review the latest results on jet-medium interactions as seen in A+A collisions at RHIC, focusing on the new techniques for full jet reconstruction.

  20. Modeling chamber transport for heavy-ion fusion

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Modeling Chamber Transport for Heavy-Ion Fusion W. M. Sharp,Peterson, "Chamber Transport of 'Foot' Pulses for Heavy-Ionstate of beam ions. Although several chamber- transport

  1. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Sharp, W. M.

    2011-01-01T23:59:59.000Z

    HIFAN 1830 INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMSAC02-05CH11231. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION467 (1992). [38] R. W. Moir, Fusion Tech. 25, 5 (1994) [39

  2. SECTION II: HEAVY ION REACTIONS

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection245C Unlimited Release PrintedDEVIATIONS F O INTERACTIONSII. HEAVY

  3. The quarkonium saga in heavy ion collisions

    E-Print Network [OSTI]

    Tserruya, Itzhak

    2013-01-01T23:59:59.000Z

    J/psi suppression was proposed more than 25 years ago as an unambiguous signature for the formation of the Quark Gluon Plasma in relativistic heavy ion collisions. After intensive efforts, both experimental and theoretical, the quarkonium saga remains exciting, producing surprising results and not fully understood. This talk focuses on recent results on quarkonium production at RHIC and the LHC.

  4. BARC TIFR Heavy Ion Accelerator Facility

    E-Print Network [OSTI]

    Shyamasundar, R.K.

    enterprise using accelerated heavy ion beams is to unravel the complexities of the nuclear world in all repulsion so that the collision process is governed by the nuclear interactions. Using a variety at this centre to pursue research in nuclear, atomic, condensed matter and bio-environmental physics. While

  5. Causal dissipative hydrodynamics for heavy ion collisions

    E-Print Network [OSTI]

    Chaudhuri, A K

    2011-01-01T23:59:59.000Z

    We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

  6. Causal dissipative hydrodynamics for heavy ion collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2011-01-23T23:59:59.000Z

    We briefly discuss the recent developments in causal dissipative hydrodynamic for relativistic heavy ion collisions. Phenomenological estimate of QGP viscosity over entropy ratio from several experimental data, e.g. STAR's $\\phi$ meson data, centrality dependence of elliptic flow, universal scaling elliptic flow etc. are discussed. QGP viscosity, extracted from hydrodynamical model analysis can have very large systematic uncertainty due to uncertain initial conditions.

  7. Heavy Ions - 88-Inch Cyclotron

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645 3,625 1,006 492 742EnergyOnItem NotEnergy,ARMFormsGasReleaseSpeechesHallNot Logged3 HanfordHarry S.Heat PumpsHeavy

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

    E-Print Network [OSTI]

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baudot, J.; Baumgart, S.; Beavis, D. R.; Bellwied, R.; Benedosso, F.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bnzarov, I.; Bombara, M.; Bonner, B. E.; 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; 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.; Clarke, R. F.; Codrington, M. J. M.; Corliss, R.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; De Silva, L. 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.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Efimov, L. G.; Elhalhuli, E.; Elnimr, M.; 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. J.; Geromitsos, A.; Geurts, F.; 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.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jena, C.; Jin, F.; Jones, C. L.; Jones, P. G.; Joseph, J.; Judd, E. G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitan, J.; Kauder, K.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Konzer, J.; Kopytine, M.; Koralt, I.; Korsch, W.; 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; Lee, J. H.; Leight, W.; LeVine, M. J.; Li, C.; Li, N.; Li, Y.; Lin, G.; 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.; 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; Mischke, A.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; 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.; Pile, P.; Planinic, M.; Ploskon, M. A.; Pluta, J.; Plyku, D.; Poljak, N.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Pujahari, P. R.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; 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.; Sahoo, R.; Sakai, S.; 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.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; 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.; Tarini, L. H.; Tarnowsky, T.; Thein, D.; Thomas, J. H.; Tian, J.; Timmins, A. R.; Timoshenko, S.; Tlusty, D.; Tokarev, M.; Trainor, T. A.; Tram, V. N.; Trentalange, S.; Tribble, Robert E.; Tsai, O. D.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; van Nieuwenhuizen, G.; Vanfossen, J. A., Jr.; Varma, R.; Vasconcelos, G. M. S.; Vasiliev, A. N.; Videbaek, F.; Vigdor, S. E.; Viyogi, Y. P.; Vokal, S.; Voloshin, S. A.; Wada, M.

    2010-01-01T23:59:59.000Z

    , Argonne, Illinois 60439, USA 2University of Birmingham, Birmingham, United Kingdom 3Brookhaven National Laboratory, Upton, New York 11973, USA 4University of California, Berkeley, California 94720, USA 5University of California, Davis, California 95616... at the Relativistic Heavy Ion Collider (RHIC) is to quantify the properties of the QCD matter created in heavy-ion collisions at high energy [1]. One key property is the medium energy density, which can be probed by its effect on a fast parton propagating through...

  9. Observation of charge-dependent azimuthal correlations and possible local strong parity violation in heavy-ion collisions 

    E-Print Network [OSTI]

    Abelev, B. I.; Aggarwal, M. M.; Ahammed, Z.; Alakhverdyants, A. V.; Anderson, B. D.; Arkhipkin, D.; Averichev, G. S.; Balewski, J.; Barannikova, O.; Barnby, L. S.; Baumgart, S.; Beavis, D. R.; Bellwied, R.; Benedosso, F.; Betancourt, M. J.; Betts, R. R.; Bhasin, A.; Bhati, A. K.; Bichsel, H.; Bielcik, J.; Bielcikova, J.; Biritz, B.; Bland, L. C.; Bnzarov, I.; Bonner, B. E.; Bouchet, J.; Braidot, E.; Brandin, A. V.; Bridgeman, A.; Bruna, E.; Bueltmann, S.; Burton, T. P.; Cai, X. Z.; Caines, H.; Sanchez, M. Calderon de la Barca; 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, P.; Clarke, R. F.; Codrington, M. J. M.; Corliss, R.; Cormier, T. M.; Cosentino, M. R.; Cramer, J. G.; Crawford, H. J.; Das, D.; Dash, S.; Daugherity, M.; De Silva, L. C.; Dedovich, T. G.; DePhillips, M.; Derevschikov, A. A.; de Souza, R. Derradi; Didenko, L.; Djawotho, P.; Dzhordzhadze, V.; Dogra, S. M.; Dong, X.; Drachenberg, J. L.; Draper, J. E.; Dunlop, J. C.; Mazumdar, M. R. Dutta; Efimov, L. G.; Elhalhuli, E.; Elnimr, M.; 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.; Gangadharan, D. R.; Ganti, M. S.; Garcia-Solis, E. J.; Geromitsos, A.; Geurts, F.; 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.; Heinz, M.; Heppelmann, S.; Hirsch, A.; Hjort, E.; Hoffman, A. M.; Hoffmann, G. W.; Hofman, D. J.; Hollis, R. S.; Huang, H. Z.; Humanic, T. J.; Huo, L.; Igo, G.; Iordanova, A.; Jacobs, P.; Jacobs, W. W.; Jakl, P.; Jena, C.; Jin, F.; Jones, C. L.; Jones, P. G.; Joseph, J.; Judd, E. G.; Kabana, S.; Kajimoto, K.; Kang, K.; Kapitan, J.; Kauder, K.; Keane, D.; Kechechyan, A.; Kettler, D.; Khodyrev, V. Yu; Kikola, D. P.; Kiryluk, J.; Kisiel, A.; Klein, S. R.; Knospe, A. G.; Kocoloski, A.; Koetke, D. D.; Konzer, J.; Kopytine, M.; Koralt, I.; Korsch, W.; Kotchenda, L.; Kouchpil, V.; Kravtsov, P.; Kravtsov, V. I.; 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, N.; Li, Y.; Lin, G.; 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.; 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; Mischke, A.; Mohanty, B.; Morozov, D. A.; Munhoz, M. G.; Nandi, B. K.; Nattrass, C.; Nayak, T. K.; Nelson, J. M.; 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.; Pile, P.; Planinic, M.; Ploskon, M. A.; Pluta, J.; Plyku, D.; Poljak, N.; Poskanzer, A. M.; Potukuchi, B. V. K. S.; Prindle, D.; Pruneau, C.; Pruthi, N. K.; Pujahari, P. R.; Putschke, J.; Raniwala, R.; Raniwala, S.; Ray, R. L.; Redwine, R.; 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.; Sahoo, R.; Sakai, S.; Sakrejda, I.; Sakuma, T.; Salur, S.; Sandweiss, J.; Schambach, J.; Scharenberg, R. P.; Schmitz, N.; Seele, J.; Seger, J.; Selyuzhenkov, I.; Semertzidis, Y.; Seyboth, P.; 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.; Sorensen, P.; Sowinski, J.; Spinka, H. M.; Srivastava, B.; 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.; 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.; Ulery, J.; Ullrich, T.; Underwood, D. G.; Van Buren, G.; 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.

    2010-01-01T23:59:59.000Z

    the existence of a new state of strongly interacting matter at high energy density. This state has now been observed in high-energy heavy-ion collisions at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Laboratory [2]. Many interesting... of Birmingham, Birmingham, United Kingdom 3Brookhaven National Laboratory, Upton, New York 11973, USA 4University of California, Berkeley, California 94720, USA 5University of California, Davis, California 95616, USA 6University of California, Los Angeles...

  10. Core-Corona Separation in Ultra-Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Klaus Werner

    2007-04-10T23:59:59.000Z

    Simple geometrical considerations show that the collision zone in high energy nuclear collisions may be divided into a central part (``core''), with high energy densities, and a peripheral part (``corona''), with smaller energy densities, more like in pp or pA collisions. We present calculations which allow to separate these two contributions, and which show that the corona contribution is quite small (but not negligible) for central collisions, but gets increasingly important with decreasing centrality. We will discuss consequences concerning results obtained in heavy ion collisions at the Relativistic Heavy Ion Collider (RHIC) and the Super Proton Synchrotron (SPS).

  11. Medium induced jet absorption at relativistic heavy ion collisions

    E-Print Network [OSTI]

    Axel Drees; Haidong Feng; Jiangyong Jia

    2005-05-31T23:59:59.000Z

    The dense medium created in Au + Au collisions at the Relativistic Heavy-Ion Collider (RHIC) significantly suppresses particle production from hard scattering processes and their characteristic back-to-back angular correlation. We present a simple model of jet absorption in dense matter which incorporates a realistic nuclear geometry. Our calculations are performed at the jet level and assume independent jet fragmentation in the vacuum. This model describes quantitatively the centrality dependence of the observed suppression of the high $p_T$ hadron yield and of the back-to-back angular correlations. The azimuthal anisotropy of high $p_T$ particle production can not be accounted for using a realistic nuclear geometry.

  12. Reversing a heavy-ion collision

    E-Print Network [OSTI]

    Mikhail Stephanov; Yi Yin

    2014-04-23T23:59:59.000Z

    We introduce a novel approach to study the longitudinal hydrodynamic expansion of the quark-gluon fluid created in heavy-ion collisions. It consists of two steps: First, we apply the maximum entropy method to reconstruct the freeze-out surface from experimentally measured particle distribution. We then take the output of the reconstruction as the "initial" condition to evolve the system back in time by solving the 1+1 ideal hydrodynamic equations analytically, using the method of Khalatnikov and Landau. We find an approximate Bjorken-like plateau in the energy density vs rapidity profile at the early times, which shrinks with time as the boundary shocks propagate inward. In Bjorken frame, the fluid velocity is close to zero within the plateau, as in the Bjorken solution, but increases outside the plateau. The results carry implications for fully numerical hydrodynamic simulations as well as models of heavy-ion collisions based on gauge-gravity duality.

  13. Imaging of granular sources in high energy heavy ion collisions

    E-Print Network [OSTI]

    Zhi-Tao Yang; Wei-Ning Zhang; Lei Huo; Jing-Bo Zhang

    2008-11-13T23:59:59.000Z

    We investigate the source imaging for a granular pion-emitting source model in high energy heavy ion collisions. The two-pion source functions of the granular sources exhibit a two-tiered structure. Using a parametrized formula of granular two-pion source function, we examine the two-tiered structure of the source functions for the imaging data of Au+Au collisions at Alternating Gradient Synchrotron (AGS) and Relativistic Heavy Ion Collider (RHIC). We find that the imaging technique introduced by Brown and Danielewicz is suitable for probing the granular structure of the sources. Our data-fitting results indicate that there is not visible granularity for the sources at AGS energies. However, the data for the RHIC collisions with the selections of $40 < {\\rm centrality} < 90%$ and $0.20

  14. 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.

    2010-09-12T23:59:59.000Z

    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.

  15. ECR plasma source for heavy ion beam charge neutralization

    E-Print Network [OSTI]

    Gilson, Erik

    plasmas are being considered as a medium for charge neutralizing heavy ion beams in order to focus beyond resonance. Keywords: Plasma focus; RF plasma; Beam charge neutralization 1. INTRODUCTION A possible heavyECR plasma source for heavy ion beam charge neutralization PHILIP C. EFTHIMION,1 ERIK GILSON,1

  16. Heavy ion irradiation of crystalline water ice

    E-Print Network [OSTI]

    Dartois, E; Boduch, P; Brunetto, R; Chabot, M; Domaracka, A; Ding, J J; Kamalou, O; Lv, X Y; Rothard, H; da Silveira, E F; Thomas, J C

    2015-01-01T23:59:59.000Z

    Under cosmic irradiation, the interstellar water ice mantles evolve towards a compact amorphous state. Crystalline ice amorphisation was previously monitored mainly in the keV to hundreds of keV ion energies. We experimentally investigate heavy ion irradiation amorphisation of crystalline ice, at high energies closer to true cosmic rays, and explore the water-ice sputtering yield. We irradiated thin crystalline ice films with MeV to GeV swift ion beams, produced at the GANIL accelerator. The ice infrared spectral evolution as a function of fluence is monitored with in-situ infrared spectroscopy (induced amorphisation of the initial crystalline state into a compact amorphous phase). The crystalline ice amorphisation cross-section is measured in the high electronic stopping-power range for different temperatures. At large fluence, the ice sputtering is measured on the infrared spectra, and the fitted sputtering-yield dependence, combined with previous measurements, is quadratic over three decades of electronic ...

  17. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    E-Print Network [OSTI]

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-01-01T23:59:59.000Z

    Analysis for a Heavy Ion Beam Chamber with Plasma Channelsthe target chamber wall, an adiabatic lens to focus the ionchamber that utilizes pre-formed plasma channels for heavy ion

  18. Grazing collisions of gravitational shock waves and entropy production in heavy ion collisions

    SciTech Connect (OSTI)

    Lin Shu; Shuryak, Edward [Department of Physics and Astronomy, SUNY, Stony Brook, New York 11794 (United States)

    2009-06-15T23:59:59.000Z

    AdS/CFT correspondence is now widely used for the study of strongly coupled plasmas, such as those produced in ultrarelativistic heavy ion collisions at the Relativistic Heavy Ion Collider. While properties of equilibrated plasma and small deviations from equilibrium are by now reasonably well understood, the plasma's initial formation and thermal equilibration is a much more challenging issue which remains to be studied. In the dual gravity language, these problems are related to the formation of bulk black holes, and studying trapped surfaces, as we do in this work, is a way to estimate the properties (temperature and entropy) of such black holes. Extending the work by Gubser et al. for central collisions, we find numerically trapped surfaces for noncentral collisions of ultrarelativistic black holes (gravitational shock waves) with different energies. We observe that beyond a certain critical impact parameter, the trapped surface does not exist, and we argue that there are some experimental indications for a similar jump in entropy production as a function of the impact parameter in real heavy ion collisions. We also present a simple solvable example of the so-called wall-on-wall collision, for colliding objects that depend on the holographic coordinate only. Finally, we critically discuss the applicability of the AdS/CFT approach to real-world heavy ion collisions.

  19. Heavy-Ion Fusion Mechanism And Predictions Of Super-Heavy Elements Production

    E-Print Network [OSTI]

    Boyer, Edmond

    Heavy-Ion Fusion Mechanism And Predictions Of Super-Heavy Elements Production Yasuhisa Abea University, Omsk, RU-644077, Russia Abstract. Fusion process is shown to firstly form largely deformed mono-ion Fusion; Fusion hindrance; Super-heavy elements; Cross section. PACS: 25.70, Jj, 25.70. Lm, 27.90. +b

  20. The Shape and Flow of Heavy Ion Collisions (490th Brookhaven Lecture)

    SciTech Connect (OSTI)

    Schenke, Bjoern [BNL Physics Department

    2014-12-18T23:59:59.000Z

    The sun can’t do it, but colossal machines like the Relativistic Heavy Ion Collider (RHIC) at Brookhaven Lab and Large Hadron Collider (LHC) in Europe sure can. Quarks and gluons make up protons and neutrons found in the nucleus of every atom in the universe. At heavy ion colliders like RHIC and the LHC, scientists can create matter more than 100,000 times hotter than the center of the sun—so hot that protons and neutrons melt into a plasma of quarks and gluons. The particle collisions and emerging quark-gluon plasma hold keys to understanding how these fundamental particles interact with each other, which helps explain how everything is held together—from atomic nuclei to human beings to the biggest stars—how all matter has mass, and what the universe looked like microseconds after the Big Bang. Dr. Schenke discusses theory that details the shape and structure of heavy ion collisions. He will also explain how this theory and data from experiments at RHIC and the LHC are being used to determine properties of the quark-gluon plasma.

  1. Detecting exotic heavy leptons at the large hadron collider.

    E-Print Network [OSTI]

    Allanach, B C; Harris, Chris M; Parker, Michael A; Richardson, P; Webber, Bryan R

    the cuts actually slightly increases with mass due to the longer time delays. 0.01 0.1 1 10 100 1000 100 200 300 400 500 600 700 800 900 1000 Cr os s se ct io n (fb ) Mass of heavy lepton (GeV) Before applying cuts After applying cuts Figure 5: Cross...

  2. Heavy Ion Reactions - Research - Cyclotron Institute

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level: National5Sales for4,645U.S. DOE Office of Science (SC) EnvironmentalGyroSolé(tm) Harmonicbet When yourecoveryG -HazmatLoadofthe 25Heavy Ion

  3. Can CP violation be observed in heavy-ion collisions?

    SciTech Connect (OSTI)

    Khriplovich, I. B., E-mail: khriplovich@inp.nsk.su; Rudenko, A. S., E-mail: a.s.rudenko@inp.nsk.su [Budker Institute of Nuclear Physics (Russian Federation)

    2012-09-15T23:59:59.000Z

    We demonstrate that, at least at present, there is no convincing way to detect CP violation in heavy-ion collisions.

  4. Heavy-ion Accelerators for Testing Microelectronic Components...

    Office of Science (SC) Website

    Heavy-ion Accelerators for Testing Microelectronic Components at LBNL Nuclear Physics (NP) NP Home About Research Facilities Science Highlights Benefits of NP Applications of...

  5. Induction linacs for heavy ion fusion research

    SciTech Connect (OSTI)

    Fessenden, T.J.

    1984-05-01T23:59:59.000Z

    The new features of employing an induction linac as a driver for inertial fusion involve (1) transport of high-current low-emittance heavy ion beams, (2) multiple independently-focussed beams threading the same accelerator structure, and (3) synthesis of voltage waveforms to accomplish beam current amplification. A research program is underway at LBL to develop accelerators that test all these features with the final goal of producing an ion beam capable of heating matter to approx. 70 eV. This paper presents a discussion of some properties of induction linacs and how they may be used for HIF research. Physics designs of the High Temperature Experiment (HTE) and the Multiple Beam Experiment (MBE) accelerators are presented along with initial concepts of the MBE induction units.

  6. High Current Ion Source Development for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Westenskow, G A; Grote, D P; Kwan, J W

    2003-09-04T23:59:59.000Z

    We are developing high-current-density high-brightness sources for Heavy Ion Fusion applications. Heavy ion driven inertial fusion requires beams of high brightness in order to achieve high power density at the target for high target gain. At present, there are no existing ion source types that can readily meet all the driver HIF requirements, though sources exist which are adequate for present experiments and which with further development may achieve driver requirements. Our two major efforts have been on alumino-silicate sources and RF plasma sources. Experiments being performed on a 10-cm alumino-silicate source are described. To obtain a compact system for a HIF driver we are studying RF plasma sources where low current beamlets are combined to produce a high current beam. A 80-kV 20-{micro}s source has produced up to 5 mA of Ar{sup +} in a single beamlet. The extraction current density was 100 mA/cm{sup 2}. We present measurements of the extracted current density as a function of RF power and gas pressure, current density uniformity, emittance, and energy dispersion (due to charge exchange).

  7. Jet Reconstruction in Heavy Ion Collisions

    E-Print Network [OSTI]

    Sevil Salur

    2009-05-12T23:59:59.000Z

    Measurements of strong suppression of inclusive hadron distributions and di-hadron correlations at high $p_{T}$, while providing evidence for partonic energy loss, also suffer from geometric biases due to the competition of energy loss and fragmentation. The measurements of fully reconstructed jets is expected to lack these biases as the energy flow is measured independently of the fragmentation details. In this article, we review the recent results from the heavy ion collisions collected by the STAR experiment at RHIC on direct jet reconstruction utilizing the modern sequential recombination and cone jet reconstruction algorithms together with their background subtraction techniques. In order to assess the jet reconstruction biases a comparison with the jet cross section measurement in $\\sqrt{s}=200$ GeV p+p collisions scaled by the number of binary nucleon-nucleon collisions to account for nuclear geometric effects is performed. Comparison of the inclusive jet cross section obtained in central Au+Au events with that in $p+p$ collisions, published previously by STAR, suggests that unbiased jet reconstruction in the complex heavy ion environment indeed may be possible.

  8. The Heavy Ion Fusion Science Virtual National Laboratory

    E-Print Network [OSTI]

    Gilson, Erik

    and collaborators. P. K. Roy et al., Nucl. Instr. and Meth. in Phys. Res. A 606 22, (2009). The four CAPS produce current through each of the four sources. P. K. Roy #12;The Heavy Ion Fusion Science Virtual National P. Gilson Princeton Plasma Physics Laboratory #12;The Heavy Ion Fusion Science Virtual National

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

    SciTech Connect (OSTI)

    Rolf Ent

    2012-04-01T23:59:59.000Z

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

  10. The role of Spectator Fragments at an electron Ion collider

    E-Print Network [OSTI]

    Sebastian White; Mark Strikman

    2010-03-10T23:59:59.000Z

    Efficient detection of spectator fragments is key to the main topics at an electron-ion collider (eIC). Any process which leads to emission of fragments or $\\gamma$'s breaks coherence in diffractive processes. Therefore this is equivalent to non-detection of rapidity gaps in pp collisions. For example, in coherent photoproduction of vector mesons their 4-momentum transfer distribution would image the "gluon charge" in the nucleus in the same way that Hofstadter measured its charge structure using elastic scattering of $\\sim$100 MeV electrons. Whereas he could measure the $\\sim$4 MeV energy loss by the electron due to excitation of nuclear energy levels (Figure 1), even the energy spread of the incident beam would prevent such an inclusive selection of quasielastic events at an eIC. The only available tool is fragment detection. Since, in our example, one finds that $\\sim100$ of deexcitations go through $\\gamma$'s or 1 neutron, rarely to 2 neutron and never to protons(due to Coulomb barrier suppression), the eIC design should emphasize their detection.

  11. Jet Structure in Heavy Ion Collisions

    E-Print Network [OSTI]

    Jean-Paul Blaizot; Yacine Mehtar-Tani

    2015-03-19T23:59:59.000Z

    We review recent theoretical developments in the study of the structure of jets that are produced in ultra relativistic heavy ion collisions. The core of the review focusses on the dynamics of the parton cascade that is induced by the interactions of a fast parton crossing a quark-gluon plasma. We recall the basic mechanisms responsible for medium induced radiation, underline the rapid disappearance of coherence effects, and the ensuing probabilistic nature of the medium induced cascade. We discuss how large radiative corrections modify the classical picture of the gluon cascade, and how these can be absorbed in a renormalization of the jet quenching parameter $\\hat q $. Then, we analyze the (wave)-turbulent transport of energy along the medium induced cascade, and point out the main characteristics of the angular structure of such a cascade. Finally, color decoherence of the in-cone jet structure is discussed. Modest contact with phenomenology is presented towards the end of the review.

  12. Bulk viscosity in heavy ion collision

    E-Print Network [OSTI]

    Victor Roy; A. K. Chaudhuri

    2012-01-20T23:59:59.000Z

    The effect of a temperature dependent bulk viscosity to entropy density ratio~($\\zeta/s$) along with a constant shear viscosity to entropy density ratio~($\\eta/s$) on the space time evolution of the fluid produced in high energy heavy ion collisions have been studied in a relativistic viscous hydrodynamics model. The boost invariant Israel-Stewart theory of causal relativistic viscous hydrodynamics is used to simulate the evolution of the fluid in 2 spatial and 1 temporal dimension. The dissipative correction to the freezeout distribution for bulk viscosity is calculated using Grad's fourteen moment method. From our simulation we show that the method is applicable only for $\\zeta/s<0.004$.

  13. Jet Structure in Heavy Ion Collisions

    E-Print Network [OSTI]

    Blaizot, Jean-Paul

    2015-01-01T23:59:59.000Z

    We review recent theoretical developments in the study of the structure of jets that are produced in ultra relativistic heavy ion collisions. The core of the review focusses on the dynamics of the parton cascade that is induced by the interactions of a fast parton crossing a quark-gluon plasma. We recall the basic mechanisms responsible for medium induced radiation, underline the rapid disappearance of coherence effects, and the ensuing probabilistic nature of the medium induced cascade. We discuss how large radiative corrections modify the classical picture of the gluon cascade, and how these can be absorbed in a renormalization of the jet quenching parameter $\\hat q $. Then, we analyze the (wave)-turbulent transport of energy along the medium induced cascade, and point out the main characteristics of the angular structure of such a cascade. Finally, color decoherence of the in-cone jet structure is discussed. Modest contact with phenomenology is presented towards the end of the review.

  14. HEAVY-ION RADIOBIOLOGY: CELLULAR STUDIES

    E-Print Network [OSTI]

    Blakely, Eleanor A.

    2013-01-01T23:59:59.000Z

    foiled parallel-plate ion chambers filled with pure nitrogenare made with a pair of ion chambers using an interposedbeen used to verify ion chamber dosimetry; (1) comparisons

  15. Design of High Luminosity Ring-Ring Electron- Light Ion Collider at CEBAF

    SciTech Connect (OSTI)

    Slawomir Bogacz; Antje Bruell; Jean Delayen; Yaroslav Derbenev; Rolf Ent; Joseph Grames; Andrew Hutton; Geoffrey Krafft; Rui Li; Nikolitsa Merminga; Benard Poelker; Bogdan Wojtsekhowski; Byung Yunn; Yuhong Zhang; C Montag

    2007-06-25T23:59:59.000Z

    Experimental studies of fundamental structure of nucleons require an electron-ion collider of a center-of-mass energy up to 90 GeV at luminosity up to 1035 cm-2s-1 with both beams polarized. A CEBAF-based collider of 9 GeV electrons/positrons and 225 GeV ions is envisioned to meet this science need and as a next step for CEBAF after the planned 12 GeV energy upgrade of the fixed target program. A ring-ring scheme of this collider developed recently takes advantage of the existing polarized electron CW beam from the CEBAF and a green-field design of an ion complex with electron cooling. We present a conceptual design and report design studies of this high-luminosity collider.

  16. Benchmarking of Neutron Production of Heavy-Ion Transport Codes

    SciTech Connect (OSTI)

    Remec, Igor [ORNL; Ronningen, Reginald M. [Michigan State University, East Lansing; Heilbronn, Lawrence [University of Tennessee, Knoxville (UTK)

    2012-01-01T23:59:59.000Z

    Accurate prediction of radiation fields generated by heavy ion interactions is important in medical applications, space missions, and in design and operation of rare isotope research facilities. In recent years, several well-established computer codes in widespread use for particle and radiation transport calculations have been equipped with the capability to simulate heavy ion transport and interactions. To assess and validate these capabilities, we performed simulations of a series of benchmark-quality heavy ion experiments with the computer codes FLUKA, MARS15, MCNPX, and PHITS. We focus on the comparisons of secondary neutron production. Results are encouraging; however, further improvements in models and codes and additional benchmarking are required.

  17. RHIC | Physics of the Relativistic Heavy Ion Collider

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

    physics (the study of the atom's constituents), astrophysics (the study of stars and planets), condensed matter physics (the science of solid matter) and cosmology (the study of...

  18. Relativistic Heavy Ion Collider | The Case for Continuing Operations

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

    make up 99 percent of visible matter in the universe today, everything from stars to planets to people. In addition to giving us a new way to explore and understand the nature of...

  19. Relativistic Heavy Ion Collider spin flipper commissioning plan

    SciTech Connect (OSTI)

    Bai, M.; Dawson, C.; Makdisi, Y.; Meng, W.; Meot, F.; Oddo, P.; Pai, C.; Pile, P.; Roser, T.

    2010-09-27T23:59:59.000Z

    The commissioning of the RHIC spin flipper in the RHIC Blue ring during the RHIC polarized proton run in 2009 showed the detrimental effects of global vertical coherent betatron oscillation induced by the 2-AC dipole plus 4-DC dipole configuration. This global orbital coherent oscillation of the RHIC beam in the Blue ring in the presence of collision modulated the beam-beam interaction between the two RHIC beams and affected Yellow beam lifetime. The experimental data at injection with different spin tunes by changing the snake current also demonstrated that it was not possible to induce a single isolated spin resonance with the global vertical coherent betatron oscillation excited by the two AC dipoles. Hence, RHIC spin flipper was re-designed to eliminate the coherent vertical betatron oscillation outside the spin flipper by adding three additional AC dipoles. This paper presents the experimental results as well as the new design.

  20. On possible $?$ vacua states in heavy ion collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2000-12-06T23:59:59.000Z

    We have simulated the possible $\\Theta$ vacua states in heavy ion collisions. In a quench like scenario, random phases of the chiral fields were evolved in a zero temperature potential incorporating the breaking of $U_A(1)$ symmetry. Initial random phases very quickly settles into oscillation around the values dictated by the potential. The simulation indicate that $\\Theta$ vacua states that can be populated in heavy ion collisions is a coherent superposition of a number of modes.

  1. MESON PRODUCTION IN RELATIVISTIC HEAVY ION COLLISIONS

    E-Print Network [OSTI]

    Schnetzer, S.R.

    2010-01-01T23:59:59.000Z

    by (kaon yield)*/*?. Fig. 27 Ion chamber voltage vs. T-Bcoincidences. Fig. ? 8 Ion chamber voltage vs. E tag29 Measured charge on the Ion chamber per beam particle vs.

  2. Triangular flow in heavy ion collisions in a multiphase transport model

    E-Print Network [OSTI]

    Jun Xu; Che Ming Ko

    2011-06-28T23:59:59.000Z

    We have obtained a new set of parameters in a multiphase transport (AMPT) model that are able to describe both the charged particle multiplicity density and elliptic flow measured in Au+Au collisions at center of mass energy $\\sqrt{s_{NN}}=200$ GeV at the Relativistic Heavy Ion Collider (RHIC), although they still give somewhat softer transverse momentum spectra. We then use the model to predict the triangular flow due to fluctuations in the initial collision geometry and study its effect relative to those from other harmonic components of anisotropic flows on the di-hadron azimuthal correlations in both central and mid-central collisions.

  3. Hydrodynamic radial and elliptic flow in heavy-ion collisions from AGS to LHC energies

    E-Print Network [OSTI]

    Gregory Kestin; Ulrich W Heinz

    2008-11-28T23:59:59.000Z

    Using ideal relativistic hydrodynamics in 2+1 dimensions, we study the collision energy dependence of radial and elliptic flow, of the emitted hadron spectra, and of the transverse momentum dependence of several hadronic particle ratios, covering the range from Alternating Gradient Synchrotron (AGS) to Large Hadron Collider (LHC) energies. These calculations establish an ideal fluid dynamic baseline that can be used to assess non-equilibrium features manifest in future LHC heavy-ion experiments. Contrary to earlier suggestions we find that a saturation and even decrease of the differential elliptic flow v_2(p_T) with increasing collision energy cannot be unambiguously associated with the QCD phase transition.

  4. Scaling of elliptic flow, recombination, and sequential freeze-out of hadrons in heavy-ion collisions 

    E-Print Network [OSTI]

    He, Min; Fries, Rainer J.; Rapp, Ralf.

    2010-01-01T23:59:59.000Z

    partons deconfine and chiral symmetry is restored [1]. One major finding by the experimental program at the Relativistic Heavy Ion Collider (RHIC) at Brookhaven National Labora- tory is the large azimuthal anisotropy of hadron transverse- momentum (p..., Texas A&M University, College Station, Texas 77843, USA 2RIKEN/BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA (Received 9 June 2010; revised manuscript received 31 August 2010; published 21 September 2010) The scaling...

  5. Proceedings of RIKEN BNL Research Center Workshop: Brookhaven Summer Program on Quarkonium Production in Elementary and Heavy Ion Collisions

    SciTech Connect (OSTI)

    Dumitru, A.; Lourenco, C.; Petreczky, P.; Qiu, J., Ruan, L.

    2011-08-03T23:59:59.000Z

    Understanding the structure of the hadron is of fundamental importance in subatomic physics. Production of heavy quarkonia is arguably one of the most fascinating subjects in strong interaction physics. It offers unique perspectives into the formation of QCD bound states. Heavy quarkonia are among the most studied particles both theoretically and experimentally. They have been, and continue to be, the focus of measurements in all high energy colliders around the world. Because of their distinct multiple mass scales, heavy quarkonia were suggested as a probe of the hot quark-gluon matter produced in heavy-ion collisions; and their production has been one of the main subjects of the experimental heavy-ion programs at the SPS and RHIC. However, since the discovery of J/psi at Brookhaven National Laboratory and SLAC National Accelerator Laboratory over 36 years ago, theorists still have not been able to fully understand the production mechanism of heavy quarkonia, although major progresses have been made in recent years. With this in mind, a two-week program on quarkonium production was organized at BNL on June 6-17, 2011. Many new experimental data from LHC and from RHIC were presented during the program, including results from the LHC heavy ion run. To analyze and correctly interpret these measurements, and in order to quantify properties of the hot matter produced in heavy-ion collisions, it is necessary to improve our theoretical understanding of quarkonium production. Therefore, a wide range of theoretical aspects on the production mechanism in the vacuum as well as in cold nuclear and hot quark-gluon medium were discussed during the program from the controlled calculations in QCD and its effective theories such as NRQCD to various models, and to the first principle lattice calculation. The scientific program was divided into three major scientific parts: basic production mechanism for heavy quarkonium in vacuum or in high energy elementary collisions; the formation of quarkonium in nuclear medium as well as the strong interacting quark-gluon matter produced in heavy ion collisions; and heavy quarkonium properties from the first principle lattice calculations. The heavy quarkonium production at a future Electron-Ion Collider (EIC) was also discussed at the meeting. The highlight of the meeting was the apparent success of the NRQCD approach at next-to-leading order in the description of the quarkonium production in proton-proton, electron-proton and electron positron collisions. Still many questions remain open in lattice calculations of in-medium quarkonium properties and in the area of cold nuclear matter effects.

  6. Signature of heavy Majorana neutrinos at a linear collider: Enhanced charged Higgs pair production

    SciTech Connect (OSTI)

    Atwood, David [Department of Physics and Astronomy, Iowa State University, Ames, Iowa 50011 (United States); Bar-Shalom, Shaouly [Physics Department, Technion-Institute of Technology, Haifa 32000 (Israel); Soni, Amarjit [Theory Group, Brookhaven National Laboratory, Upton, New York 11973 (United States)

    2007-08-01T23:59:59.000Z

    A charged Higgs pair can be produced at an ee collider through a t-channel exchange of a heavy neutrino (N) via e{sup +}e{sup -}{yields}H{sup +}H{sup -} and, if N is a Majorana particle, also via the lepton number violating (LNV) like-sign reaction e{sup {+-}}e{sup {+-}}{yields}H{sup {+-}}H{sup {+-}}. Assuming no a priori relation between the effective eNH{sup +} coupling ({xi}) and light neutrino masses, we show that this interaction vertex can give a striking enhancement to these charged Higgs pair production processes. In particular, the LNV H{sup -}H{sup -} signal can probe N at the International Linear Collider (ILC) in the mass range 100 GeV < or approx. m{sub N} < or approx. 10{sup 4} TeV and with the effective mixing angle {xi} in the range 10{sup -4} < or approx. {xi}{sup 2} < or approx. 10{sup -8}--well within its perturbative unitarity bound and the {beta}{beta}{sub 0{nu}} limit. The lepton number conserving e{sup +}e{sup -}{yields}H{sup +}H{sup -} mode can be sensitive to, e.g., an O(10) TeV heavy Majorana neutrino at a 500 GeV ILC, if {xi}{sup 2} > or approx. 0.001.

  7. INERTIAL FUSION DRIVEN BY INTENSE HEAVY-ION BEAMS

    SciTech Connect (OSTI)

    Sharp, W. M.; Friedman, A.; Grote, D. P.; Barnard, J. J.; Cohen, R. H.; Dorf, M. A.; Lund, S. M.; Perkins, L. J.; Terry, M. R.; Logan, B. G.; Bieniosek, F. M.; Faltens, A.; Henestroza, E.; Jung, J. Y.; Kwan, J. W.; Lee, E. P.; Lidia, S. M.; Ni, P. A.; Reginato, L. L.; Roy, P. K.; Seidl, P. A.; Takakuwa, J. H.; Vay, J.-L.; Waldron, W. L.; Davidson, R. C.; Gilson, E. P.; Kaganovich, I. D.; Qin, H.; Startsev, E.; Haber, I.; Kishek, R. A.; Koniges, A. E.

    2011-03-31T23:59:59.000Z

    Intense heavy-ion beams have long been considered a promising driver option for inertial-fusion energy production. This paper briefly compares inertial confinement fusion (ICF) to the more-familiar magnetic-confinement approach and presents some advantages of using beams of heavy ions to drive ICF instead of lasers. Key design choices in heavy-ion fusion (HIF) facilities are discussed, particularly the type of accelerator. We then review experiments carried out at Lawrence Berkeley National Laboratory (LBNL) over the past thirty years to understand various aspects of HIF driver physics. A brief review follows of present HIF research in the US and abroad, focusing on a new facility, NDCX-II, being built at LBNL to study the physics of warm dense matter heated by ions, as well as aspects of HIF target physics. Future research directions are briefly summarized.

  8. Heavy Quarkonium Production at sqrt{s_{NN}} = 200 GeV 

    E-Print Network [OSTI]

    Cervantes, Matthew

    2012-12-12T23:59:59.000Z

    are not fully in agreement with predicted observables from either model. The Relativistic Heavy Ion Collider (RHIC), and the Solenoidal Tracker At RHIC (STAR) is well suited to further explore heavy quarkonium production. The Heavy Flavor program...

  9. Heavy-ion induced desorption yields of amorphous carbon films bombarded with 4.2 MeV/u lead ions

    E-Print Network [OSTI]

    Mahner, E; Küchler, D; Scrivens, R; Costa Pinto, P; Yin Vallgren, C; Bender, M

    2011-01-01T23:59:59.000Z

    During the past decade, intense experimental studies on the heavy-ion induced molecular desorption were performed in several particle accelerator laboratories worldwide in order to understand and overcome large dynamic pressure rises caused by lost beam ions. Different target materials and various coatings were studied for desorption and mitigation techniques were applied to heavy-ion accelerators. For the upgrade of the CERN injector complex, a coating of the Super Proton Synchrotron (SPS) vacuum system with a thin film of amorphous carbon is under study to mitigate the electron cloud effect observed during SPS operation with the nominal proton beam for the Large Hadron Collider (LHC). Since the SPS is also part of the heavy-ion injector chain for LHC, dynamic vacuum studies of amorphous carbon films are important to determine their ion induced desorption yields. At the CERN Heavy Ion Accelerator (LINAC 3), carbon-coated accelerator-type stainless steel vacuum chambers were tested for desorption using 4.2 Me...

  10. Probing Shadowed Nuclear Sea with Massive Gauge Bosons in the Future Heavy-Ion Collisions

    E-Print Network [OSTI]

    Ru, Peng; Wang, Enke; Zhang, Wei-Ning

    2015-01-01T23:59:59.000Z

    The production of the massive bosons $Z^0$ and $W^{\\pm}$ could provide an excellent tool to study cold nuclear matter effects and the modifications of nuclear parton distribution functions (nPDFs) relative to parton distribution functions (PDFs) of a free proton in high energy nuclear reactions at the LHC as well as in heavy-ion collisions (HIC) with much higher center-of mass energies available in the future colliders. In this paper we calculate the rapidity and transverse momentum distributions of the vector boson and their nuclear modification factors in p+Pb collisions at $\\sqrt{s_{NN}}=63$TeV and in Pb+Pb collisions at $\\sqrt{s_{NN}}=39$TeV in the framework of perturbative QCD by utilizing three parametrization sets of nPDFs: EPS09, DSSZ and nCTEQ. It is found that in heavy-ion collisions at such high colliding energies, both the rapidity distribution and the transverse momentum spectrum of vector bosons are considerably suppressed in wide kinematic regions with respect to p+p reactions due to large nucl...

  11. NUCLEAR STRUCTURE AND HEAVY-ION FUSION

    E-Print Network [OSTI]

    Stokstad, R.G.

    2010-01-01T23:59:59.000Z

    Nuclear Structure and Heavy-Ton Fusion* A series of lecturesthe cross section for fusion in the experiments consideredEffects g in III. Subharrier Fusion Cross Sections for Light

  12. HEAVY-ION IMAGING APPLIED TO MEDICINE

    E-Print Network [OSTI]

    Fabrikant, J.I.

    2013-01-01T23:59:59.000Z

    heavy particles rat h er than the vax~at1.on 1n t h e x-rayprograms on the a PDPll-34 and VAX- 780 computers. The image

  13. Review of Heavy-ion Induced Desorption Studies for Particle Accelerators

    E-Print Network [OSTI]

    Mahner, E

    2008-01-01T23:59:59.000Z

    During high-intensity heavy-ion operation of several particle accelerators worldwide, large dynamic pressure rises of orders of magnitude were caused by lost beam ions that impacted under grazing angle onto the vacuum chamber walls. This ion-induced desorption, observed, for example, at CERN, GSI, and BNL, can seriously limit the ion intensity, luminosity, and beam lifetime of the accelerator. For the heavyion program at CERN's Large Hadron Collider collisions between beams of fully stripped lead (208Pb82+) ions with a beam energy of 2.76 TeV/u and a nominal luminosity of 10**27 cm**-2 s**-1 are foreseen. The GSI future project FAIR (Facility for Antiproton and Ion Research) aims at a beam intensity of 10**12 uranium (238U28+) ions per second to be extracted from the synchrotron SIS18. Over the past years an experimental effort has been made to study the observed dynamic vacuum degradations, which are important to understand and overcome for present and future particle accelerators. The paper reviews the resu...

  14. Inferring Magnetospheric Heavy Ion Density using EMIC Waves

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Kim, Hyomin; Lee, Dong-Hun

    2014-05-01T23:59:59.000Z

    We present a method to infer heavy ion concentration ratios from EMIC wave observations that result from ionion hybrid (IIH) resonance. A key feature of the ion-ion hybrid resonance is the concentration of wave energy in a field-aligned resonant mode that exhibits linear polarization. This mode converted wave is localized at the location where the frequency of a compressional wave driver matches the IIH resonance condition, which depends sensitively on the heavy ion concentration. This dependence makes it possible to estimate the heavy ion concentration ratio. In this letter, we evaluate the absorption coefficients at the IIH resonance at Earth's geosynchronous orbit for variable concentrations of He+ and field-aligned wave numbers using a dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentrations, it only occurs for a limited range of field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Using the wave absorption and observed EMIC waves from GOES-12 satellite, we demonstrate how this technique can be used to estimate that the He+ concentration is around 4% near L = 6.6.

  15. THE DEVELOPMENT OF HEAVY-ION ACCELERATORS AS DRIVERS FOR INERTIALLY CONFINED FUSION

    E-Print Network [OSTI]

    Herrmannsfeldt, W.b.

    2010-01-01T23:59:59.000Z

    29 The Fission-fusion Hybrid - iii - General DiscussionInteraction in Heavy Ion Fusion BIBLIOGRAPHY HEAVY IONReactor Designs . . . 27 Pure Fusion Power Reactor Tritium

  16. LEIC - A Polarized Low Energy Electron-ion Collider at Jefferson Lab

    SciTech Connect (OSTI)

    Derbenev, Yaroslav S. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Hutton, Andrew M. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Krafft, Geoffrey A. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Li, Rui [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Lin, Fanglei [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Morozov, Vasiliy [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Nissen, Edward W. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Yunn, Byung C. [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Zhang, He [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States); Sullivan, Michael K. [SLAC National Accelerator Laboratory, Menlo Park, CA (United States); Zhang, Yuhong [Thomas Jefferson National Accelerator Facility, Newport News, VA (United States)

    2013-06-01T23:59:59.000Z

    A polarized electron-ion collider is envisioned as the future nuclear science program at JLab beyond the 12 GeV CEBAF. Presently, a medium energy collider (MEIC) is set as an immediate goal with options for a future energy upgrade. A comprehensive design report for MEIC has been released recently. The MEIC facility could also accommodate electron and proton/ion collisions in a low CM energy range, covering proton energies from 10 to 25 GeV and ion energies with a similar magnetic rigidity, for additional science reach. In this paper, we present a conceptual design of this low energy collider, LEIC, showing its luminosity can reach above 10{sup 33} cm{sup -2}s{sup -1}. The design specifies that the large booster of the MEIC is converted to a low energy ion collider ring with an interaction region and an electron cooler integrated into it. The design provides options for either sharing the detector with the MEIC or a dedicated low energy detector in a third collision point, with advantages of either a minimum cost or extra detection parallel to the MEIC operation, respectively. The LEIC could be positioned as the first and low cost phase of a multi-stage approach to realize the full MEIC.

  17. RECENT PROGRESS IN HEAVY ION SOURCES

    E-Print Network [OSTI]

    Clark, D.J.

    2010-01-01T23:59:59.000Z

    of hydrogen into thermonuclear fusion reactors. A summary ofFusion Plasma Sources Other sources of high charge state ions include the dense plasma in magnetic confinement thermonuclear

  18. Elucidating Jet Energy Loss in Heavy Ion Collisions

    E-Print Network [OSTI]

    N. Grau; for the ATLAS Collaboration

    2008-11-05T23:59:59.000Z

    Very soon the LHC will provide beams for heavy ion collisions at 5.52 TeV/nucleon. This center-of-mass energy results in a large cross-section for producing high-$E_T$ ($>$ 50 GeV) jets that are distinct from the soft, underlying event. This brings with it the possibility of performing full jet reconstruction to directly study jet energy loss in the medium produced in heavy ion collisions. In this note, we present the current state of jet reconstruction performance studies in heavy ion events using the ATLAS detector. We also discuss the possibilities of energy loss measurements available with full jet reconstruction: single jet $R_{AA}$ and di-jet and $\\gamma$-jet correlations.

  19. Heavy metal ions are potent inhibitors of protein folding

    SciTech Connect (OSTI)

    Sharma, Sandeep K. [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland); Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Goloubinoff, Pierre [Departement de Biologie Moleculaire Vegetale, Universite de Lausanne, CH-1015 Lausanne (Switzerland); Christen, Philipp [Biochemisches Institut, Universitaet Zuerich, CH-8057 Zuerich (Switzerland)], E-mail: christen@bioc.uzh.ch

    2008-07-25T23:59:59.000Z

    Environmental and occupational exposure to heavy metals such as cadmium, mercury and lead results in severe health hazards including prenatal and developmental defects. The deleterious effects of heavy metal ions have hitherto been attributed to their interactions with specific, particularly susceptible native proteins. Here, we report an as yet undescribed mode of heavy metal toxicity. Cd{sup 2+}, Hg{sup 2+} and Pb{sup 2+} proved to inhibit very efficiently the spontaneous refolding of chemically denatured proteins by forming high-affinity multidentate complexes with thiol and other functional groups (IC{sub 50} in the nanomolar range). With similar efficacy, the heavy metal ions inhibited the chaperone-assisted refolding of chemically denatured and heat-denatured proteins. Thus, the toxic effects of heavy metal ions may result as well from their interaction with the more readily accessible functional groups of proteins in nascent and other non-native form. The toxic scope of heavy metals seems to be substantially larger than assumed so far.

  20. QCD plasma instability and thermalisation at heavy ion collisions

    E-Print Network [OSTI]

    Dietrich Bodeker; Kari Rummukainen

    2007-11-13T23:59:59.000Z

    Under suitable non-equilibrium conditions QCD plasma can develop plasma instabilities, where some modes of the plasma grow exponentially. It has been argued that these instabilities can play a significant role in the thermalisation of the plasma in heavy-ion collision experiments. We study the instability in SU(2) plasmas using the hard thermal loop effective lattice theory, which is suitable for studying real-time evolution of long wavelength modes in the plasma. We observe that under suitable conditions the plasma can indeed develop an instability which can grow to a very large magnitude, necessary for the rapid thermalisation in heavy-ion collisions.

  1. Low Density Nuclear Matter in Heavy Ion Collisions

    E-Print Network [OSTI]

    Qin, Lijun

    2010-01-14T23:59:59.000Z

    2 ,a a = 93.15 MeV/c 2 , and the pairing term, B, is 0 MeV/c 2 for odd-even or even-odd nuclei, -11.2 MeV/c 2 for even-even nuclei and +11.2 MeV/c 2 for odd-odd nuclei [24, 25, 26, 27, 28]. A classical result is shown in the Fig. 2. 6 Fig. 2. Binding... dissertation project possible. vii TABLE OF CONTENTS CHAPTER Page I INTRODUCTION .......................... 1 A. General Picture of Heavy Ion Collisons ........... 1 B. Transport Models to Simulate Heavy Ion Collisions .... 2 C...

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

    SciTech Connect (OSTI)

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

    2011-08-09T23:59:59.000Z

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

  3. Multipole decomposition of potentials in relativistic heavy ion collisions

    E-Print Network [OSTI]

    A. Isar

    2006-04-13T23:59:59.000Z

    In relativistic heavy ion collisions an exact multipole decomposition of the Lorentz transformed time dependent Coulomb potentials in a coordinate system with equal constant, but opposite velocities of the ions, is obtained for both zero and different from zero impact parameter. The case of large values of $\\gamma$ and the gauge transformation of the interaction removing both the $\\gamma$ dependence and the $\\ln b$ dependence are also considered.

  4. US Heavy Ion Beam Research for Energy Density Physics Applications and Fusion

    E-Print Network [OSTI]

    2005-01-01T23:59:59.000Z

    heavy ion inertial fusion energy. ACKNOWLEDGEMENTS Thisheavy ion inertial fusion energy. These include: neutralizedto drift axially). For fusion energy applications, either

  5. Formation and Collapse of False Vacuum Bubbles in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Rajarshi Ray; Soma Sanyal; Ajit M. Srivastava

    2002-09-10T23:59:59.000Z

    It is possible that under certain situations, in a relativistic heavy-ion collision, partons may expand out forming a shell like structure. We analyze the process of hadronization in such a picture for the case when the quark-hadron transition is of first order, and argue that the inside region of such a shell must correspond to a supercooled (to $T = 0$) deconfined vacuum. Hadrons from that region escape out, leaving a bubble of pure deconfined vacuum with large vacuum energy. This bubble undergoes relativistic collapse, with highly Lorentz contracted bubble walls, and may concentrate the entire energy into extremely small regions. Eventually different portions of bubble wall collide, with the energy being released in the form of particle production. Thermalization of this system can lead to very high temperatures. With a reasonably conservative set of parameters, at LHC, the temperature of the hot spot can reach as high as 3 GeV, and well above it with more optimistic parameters. Such a hot spot can leave signals like large $P_T$ partons, dileptons, and enhanced production of heavy quarks. We also briefly discuss a speculative possibility where the electroweak symmetry may get restored in the highly dense region resulting from the decay of the bubble wall via the phenomenon of non-thermal symmetry restoration (which is usually employed in models of pre-heating after inflation). If that could happen then the possibility may arise of observing sphaleron induced baryon number violation in relativistic heavy-ion collisions.

  6. A Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHC Energies

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    G 30 (2004) S1155 A Cone Jet-Finding Algorithm for Heavy-IonA Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHCSwitzerland Abstract. Standard jet ?nding techniques used in

  7. Heavy-Ion-Fusion-Science: Summary of U.S. Progress

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    IAEA-06 Topic IF Heavy-Ion-Fusion-Science: Summary of U.S.W.L. Waldron, U.S. Heavy Ion Fusion Science Virtual NationalExperiment at PPPL. [1] Fusion Energy Sciences Advisory

  8. Heavy ion fusion science research for high energy density physics and fusion applications

    E-Print Network [OSTI]

    Logan, B.G.

    2007-01-01T23:59:59.000Z

    cost direct plasma MHD direct conversion [38], as well as toT-lean targets and direct conversion for heavy ion fusion. [conversion loss of beam energy into x-rays. High ablation velocities with heavy ion direct

  9. Damage Evolution in GaN Under MeV Heavy Ion Implantation. | EMSL

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

    Evolution in GaN Under MeV Heavy Ion Implantation. Damage Evolution in GaN Under MeV Heavy Ion Implantation. Abstract: Damage evaluation processes in patterned GaN implanted by 3...

  10. Heavy ion collisions and the pre-equilibrium exciton model

    SciTech Connect (OSTI)

    Betak, E. [Institute of Physics SAS, 84511 Bratislava (Slovakia); Faculty of Philosophy and Science, Silesian Univ., 74601 Opava (Czech Republic)

    2012-10-20T23:59:59.000Z

    We present a feasible way to apply the pre-equilibrium exciton model in its masterequation formulation to heavy-ion induced reactions including spin variables. Emission of nucleons, {gamma}'s and also light clusters is included in our model.

  11. Initial Parton Distribution just after Heavy Ion Collisions

    E-Print Network [OSTI]

    Ghi R. Shin; Kang S. Lee

    2006-12-08T23:59:59.000Z

    We study the initial distribution of a parton system which is formed just after relativistic heavy ion collision by the elastic scattering among the constituent partons in details and analyze the baryon and strangeness contents of the primary parton system. We present the rapidity and energy distributions of the system.

  12. A short course on Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2012-07-23T23:59:59.000Z

    Some ideas/concepts in relativistic heavy ion collisions are discussed. To a large extent, the discussions are non-comprehensive and non-rigorous. It is intended for fresh graduate students of Homi Bhabha National Institute, Kolkata Centre, who are intending to pursue career in theoretical /experimental high energy nuclear physics. Comments and criticisms will be appreciated.

  13. A short course on Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Chaudhuri, A K

    2012-01-01T23:59:59.000Z

    Some ideas/concepts in relativistic heavy ion collisions are discussed. To a large extent, the discussions are non-comprehensive and non-rigorous. It is intended for fresh graduate students of Homi Bhabha National Institute, Kolkata Centre, who are intending to pursue career in theoretical /experimental high energy nuclear physics. Comments and criticisms will be appreciated.

  14. Resonance Absorption and Regeneration in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Sascha Vogel; Marcus Bleicher

    2005-05-10T23:59:59.000Z

    The regeneration of hadronic resonances is discussed for heavy ion collisions at SPS and SIS-300 energies. The time evolutions of Delta, rho and phi resonances are investigated. Special emphasize is put on resonance regeneration after chemical freeze-out. The emission time spectra of experimentally detectable resonances are explored.

  15. Benchmarking Heavy Ion Transport Codes FLUKA, HETC-HEDS MARS15, MCNPX, and PHITS

    SciTech Connect (OSTI)

    Ronningen, Reginald Martin [Michigan State University; Remec, Igor [Oak Ridge National Laboratory; Heilbronn, Lawrence H. [University of Tennessee-Knoxville

    2013-06-07T23:59:59.000Z

    Powerful accelerators such as spallation neutron sources, muon-collider/neutrino facilities, and rare isotope beam facilities must be designed with the consideration that they handle the beam power reliably and safely, and they must be optimized to yield maximum performance relative to their design requirements. The simulation codes used for design purposes must produce reliable results. If not, component and facility designs can become costly, have limited lifetime and usefulness, and could even be unsafe. The objective of this proposal is to assess the performance of the currently available codes � PHITS, FLUKA, MARS15, MCNPX, and HETC-HEDS � that could be used for design simulations involving heavy ion transport. We plan to access their performance by performing simulations and comparing results against experimental data of benchmark quality. Quantitative knowledge of the biases and the uncertainties of the simulations is essential as this potentially impacts the safe, reliable and cost effective design of any future radioactive ion beam facility. Further benchmarking of heavy-ion transport codes was one of the actions recommended in the �Report of the 2003 RIA R&D Workshop".

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

    SciTech Connect (OSTI)

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

    1989-03-01T23:59:59.000Z

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

  17. Energy loss, hadronization and hadronic interactions of heavy flavors in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Cao, Shanshan; Bass, Steffen A

    2015-01-01T23:59:59.000Z

    We construct a theoretical framework to describe the evolution of heavy flavors produced in relativistic heavy-ion collisions. The in-medium energy loss of heavy quarks is described using our modified Langevin equation that incorporates both quasi-elastic scatterings and the medium-induced gluon radiation. The space-time profiles of the fireball is described by a (2+1)-dimensional hydrodynamics simulation. A hybrid model of fragmentation and coalescence is utilized for heavy quark hadronization, after which the produced heavy mesons together with the soft hadrons produced from the bulk QGP are fed into the hadron cascade UrQMD model to simulate the subsequent hadronic interactions. We find that the medium-induced gluon radiation contributes significantly to heavy quark energy loss at high $p_\\mathrm{T}$; heavy-light quark coalescence enhances heavy meson production at intermediate $p_\\mathrm{T}$; and scatterings inside the hadron gas further suppress the $D$ meson $R_\\mathrm{AA}$ at large $p_\\mathrm{T}$ and e...

  18. Elliptic flow and energy loss of heavy quarks in ultra-relativistic heavy ion collisions

    E-Print Network [OSTI]

    Jan Uphoff; Oliver Fochler; Zhe Xu; Carsten Greiner

    2011-08-24T23:59:59.000Z

    The space-time propagation of heavy quarks in ultra-relativistic heavy ion collisions is studied within the partonic transport model Boltzmann Approach of MultiParton Scatterings (BAMPS). In this model heavy quarks interact with the partonic medium via binary scatterings. The cross sections for these interactions are calculated with leading order perturbative QCD, but feature a more precise Debye screening derived within the hard thermal loop approximation and obey the running of the coupling. Within this framework the elliptic flow and the nuclear modification factor of heavy quarks are computed for RHIC and LHC energies and compared to available experimental data. It is found that binary scatterings alone cannot reproduce the data and, therefore, radiative corrections have to be taken into account.

  19. Dynamical analysis on heavy-ion fusion reactions near Coulomb barrier

    E-Print Network [OSTI]

    Zhao-Qing Feng; Gen-Ming Jin; Feng-Shou Zhang

    2007-11-23T23:59:59.000Z

    The shell correction is proposed in the improved isospin dependent quantum molecular dynamics (ImIQMD) model, which plays an important role in heavy-ion fusion reactions near Coulomb barrier. By using the ImIQMD model, the static and dynamical fusion barriers, dynamical barrier distribution in the fusion reactions are analyzed systematically. The fusion and capture excitation functions for a series of reaction systems are calculated and compared with experimental data. It is found that the fusion cross sections for neutron-rich systems increase obviously, and the strong shell effects of two colliding nuclei result in a decrease of the fusion cross sections at the sub-barrier energies. The lowering of the dynamical fusion barriers favors the enhancement of the sub-barrier fusion cross sections, which is related to the nucleon transfer and the neck formation in the fusion reactions.

  20. Jet quenching and $?$-jet correlation in high-energy heavy-ion collisions

    E-Print Network [OSTI]

    Xin-Nian Wang; Yan Zhu

    2014-07-16T23:59:59.000Z

    Medium modification of $\\gamma$-tagged jets in high-energy heavy-ion collisions is investigated within a linearized Boltzmann transport model which includes both elastic parton scattering and induced gluon emission. In Pb+Pb collisions at $\\sqrt{s}=2.76$ TeV, a $\\gamma$-tagged jet is seen to lose 15\\% of its energy at 0-10\\% central collisions. Simulations also point to a sizable azimuthal angle broadening of $\\gamma$-tagged jets at the tail of a distribution which should be measurable when experimental errors are significantly reduced. An enhancement at large $z_\\text{jet}=p_L/E_{\\text{jet}}$ in jet fragmentation function at the Large Hadron Collider (LHC) can be attributed to the dominance of leading particles in the reconstructed jet. A $\\gamma-$tagged jet fragmentation function is shown to be more sensitive to jet quenching, therefore a better probe of the jet transport parameter.

  1. IMAGING WITH A MULTIPLANE MULTIWIRE PROPORTIONAL CHAMBER USING HEAVY ION BEAMS

    E-Print Network [OSTI]

    Chu, W.T.

    2010-01-01T23:59:59.000Z

    1. When the he^vy ions penetrate the chamber, the resultingMULTIWIRE PROPORTIONAL CHAMBER USING HEAVY-ION BEAMS* U. T.Ion Beam Studies and Imaging with a Nultiplane Multiwire Proportional Chamber,"

  2. Self-aligned nanostructures created by swift heavy ion irradiation

    SciTech Connect (OSTI)

    Gehrke, Hans-Gregor; Nix, Anne-Katrin; Hofsaess, Hans [2. Physikalisches Institut, Universitaet Goettingen, Friedrich-Hundplatz 1, D-37077 Goettingen (Germany); Krauser, Johann [Hochschule Harz, Friedrichstrasse 57-59, D-38855 Wernigerode (Germany); Trautmann, Christina [GSI Helmholzzentrum fuer Schwerionenforschung, Planckstr. 1, D-64291 Darmstadt (Germany); Weidinger, Alois [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Hahn-Meitner-Platz 1, D-14109 Berlin (Germany)

    2010-05-15T23:59:59.000Z

    In tetrahedral amorphous carbon (ta-C) swift heavy ions create conducting tracks of about 8 nm in diameter. To apply these nanowires and implement them into nanodevices, they have to be contacted and gated. In the present work, we demonstrate the fabrication of conducting vertical nanostructures in ta-C together with self-aligned gate electrodes. A multilayer assembly is irradiated with GeV heavy ions and subsequently exposed to several selective etching processes. The samples consist of a Si wafer as substrate covered by a thin ta-C layer. On top is deposited a SiN{sub x} film for insulation, a Cr layer as electrode, and finally a polycarbonate film as ion track template. Chemical track etching opens nanochannels in the polymer which are self-aligned with the conducting tracks in ta-C because they are produced by the same ions. Through the pores in the polymer template, the Cr and SiN{sub x} layers are opened by ion beam sputtering and plasma etching, respectively. The resulting structure consists of nanowires embedded in the insulating carbon matrix with a built in gate electrode and has potential application as gated field emission cathode.

  3. The Nuclear Symmetry Energy in Heavy Ion Collisions

    E-Print Network [OSTI]

    Wolter, Hermann

    2015-01-01T23:59:59.000Z

    In this contribution I discuss the nuclear symmetry energy in the regime of hadronic degrees of freedom. The density dependence of the symmetry energy is important from very low densities in supernova explosions, to the structure of neutron-rich nuclei around saturation density, and to several times saturation density in neutron stars. Heavy ion collisions are the only means to study this density dependence in the laboratory. Numerical simulations of transport theories are used to extract the equation-of-state, and thus also the symmetry energy. I discuss some examples, which relate particularly to the high density symmetry energy, which is of particular interest today. I review the status and point out some open problems in the determination of the symmetry energy in heavy ion collisions.

  4. Kaon production in heavy ion reactions at intermediate energies

    E-Print Network [OSTI]

    Christian Fuchs

    2005-09-01T23:59:59.000Z

    The article reviews the physics related to kaon and antikaon production in heavy ion reactions at intermediate energies. Chiral dynamics predicts substantial modifications of the kaon properties in a dense nuclear environment. The status of the theoretical predictions as well as experimental evidences for medium effects such as repulsive/attractive mass shifts for $K^+/K^-$ are reviewed. In the vicinity of the thresholds, and even more pronounced below threshold, the production of strangeness is a highly collective process. Starting from elementary reaction channels the phenomenology of $K^+$ and $K^-$ production, i.e. freeze-out densities, time scales etc. as derived from experiment and theoretical transport calculations is presented. Below threshold kaon production shows a high sensitivity on the nuclear compression reached in heavy ion reactions. This allows to put constraints on the nuclear equation-of-state which are finally discussed.

  5. Temperature of projectile like fragments in heavy ion collisions

    E-Print Network [OSTI]

    Gupta, S Das; Chaudhuri, G

    2013-01-01T23:59:59.000Z

    A model in which a projectile like fragment can be simply regarded as a remnant after removal of some part of the projectile leads to an excited fragment. This excitation energy can be calculated with a Hamiltonian that gives correct nuclear matter binding, compressibility and density distribution in finite nuclei. In heavy ion collisions the model produces a dependence of excitation energy on impact parameter which appears to be correct but the magnitude of the excitation energy falls short. It is argued that dynamic effects left out in the model will increase this magnitude. The model can be directly extended to include dynamics but at the expense of increased computation. For many calculations for observables, a temperature is an easier tool to use rather than an excitation energy. Hence temperature dependences on impact parameter in heavy ion collisions are displayed.

  6. Temperature of projectile like fragments in heavy ion collisions

    E-Print Network [OSTI]

    S. Das Gupta; S. Mallik; G. Chaudhuri

    2013-09-27T23:59:59.000Z

    A model in which a projectile like fragment can be simply regarded as a remnant after removal of some part of the projectile leads to an excited fragment. This excitation energy can be calculated with a Hamiltonian that gives correct nuclear matter binding, compressibility and density distribution in finite nuclei. In heavy ion collisions the model produces a dependence of excitation energy on impact parameter which appears to be correct but the magnitude of the excitation energy falls short. It is argued that dynamic effects left out in the model will increase this magnitude. The model can be directly extended to include dynamics but at the expense of increased computation. For many calculations for observables, a temperature is an easier tool to use rather than an excitation energy. Hence temperature dependences on impact parameter in heavy ion collisions are displayed.

  7. Study of ?-charge correlation in heavy ion collisions, various approaches

    E-Print Network [OSTI]

    Prithwish Tribedy; Subhasis Chattopadhyay; Aihong Tang

    2011-08-11T23:59:59.000Z

    Event-by-event \\gamma-charge correlation is used in studying systems going through QCD chiral phase transition. In this paper various methods for measuring \\gamma-charge correlation in heavy ion collisions have been discussed. Dynamical fluctuation due to formation of domains of DCC that can affect \\gamma-charge correlation has been discussed. We study known detector and statistical effects involved in these measurements and suggest suitable robust observables \\Delta\

  8. Multiphase transport model for heavy ion collisions at RHIC

    E-Print Network [OSTI]

    Zi-wei Lin; Subrata Pal; C. M. Ko; Bao-An Li; Bin Zhang

    2001-05-18T23:59:59.000Z

    Using a multiphase transport model (AMPT) with both partonic and hadronic interactions, we study the multiplicity and transverse momentum distributions of charged particles such as pions, kaons and protons in central Au+Au collisions at RHIC energies. Effects due to nuclear shadowing and jet quenching on these observables are also studied. We further show preliminary results on the production of multistrange baryons from the strangeness-exchange reactions during the hadronic stage of heavy ion collisions.

  9. First Order Phase Transition in Intermediate Energy Heavy Ion Collisions

    E-Print Network [OSTI]

    J. Pan; S. Das Gupta; M. Grant

    1997-11-01T23:59:59.000Z

    We model the disassembly of an excited nuclear system formed as a result of a heavy ion collision. We find that, as the beam energy in central collisions in varied, the dissociating system crosses a liquid-gas coexistence curve, resulting in a first-order phase transition. Accessible experimental signatures are identified: a peak in specific heat, a power-law yield for composites, and a maximum in the second moment of the yield distribution.

  10. Isotope analysis in central heavy ion collisions at intermediate energies

    E-Print Network [OSTI]

    NUCL-EX Collaboration; :; E. Geraci; U. Abbondanno; L. Bardelli; S. Barlini; M. Bini; M. Bruno; F. Cannata; G. Casini; M. Chiari; M. D'Agostino; J. DeSanctis; A. Giussani; F. Gramegna; V. L. Kravchuk; A. L. Lanchais; P. Marini; A. Moroni; A. Nannini; A. Olmi; A. Ordine; G. Pasquali; S. Piantelli; G. Poggi; G. Vannini

    2006-09-29T23:59:59.000Z

    Symmetry energy is a key quantity in the study of the equation of state of asymmetric nuclear matter. Heavy ion collisions at low and intermediate energies, performed at Laboratori Nazionali di Legnaro and Laboratori Nazionali del Sud, can be used to extract information on the symmetry energy coefficient Csym, which is currently poorly known but relevant both for astrophysics and for structure of exotic nuclei.

  11. The Electron Beam Ion Source (EBIS)

    ScienceCinema (OSTI)

    Brookhaven Lab

    2010-01-08T23:59:59.000Z

    Brookhaven National Lab has successfully developed a new pre-injector system, called the Electron Beam Ion Source, for the Relativistic Heavy Ion Collider (RHIC) and NASA Space Radiation Laboratory science programs. The first of several planned improvemen

  12. Recent U.S. advances in ion-beam-driven high energy density physics and heavy ion fusion

    E-Print Network [OSTI]

    2006-01-01T23:59:59.000Z

    physics and heavy ion fusion energy drivers, including bothoptions towards inertial fusion energy. Acknowledgements:fusion drivers for inertial fusion energy. 1. Introduction A

  13. Modeling chamber transport for heavy-ion fusion

    SciTech Connect (OSTI)

    Sharp, W.M.; Callahan, D.A.; Tabak, M.; Yu, S.S.; Peterson, P.F.; Welch, D.R.; Rose, D.V.; Olson, C.L.

    2002-10-01T23:59:59.000Z

    In a typical thick-liquid-wall scenario for heavy-ion fusion (HIF), between seventy and two hundred high-current beams enter the target chamber through ports and propagate about three meters to the target. Since molten-salt jets are planned to protect the chamber wall, the beams move through vapor from the jets, and collisions between beam ions and this background gas both strip the ions and ionize the gas molecules. Radiation from the preheated target causes further beam stripping and gas ionization. Due to this stripping, beams for heavy-ion fusion are expected to require substantial neutralization in a target chamber. Much recent research has, therefore, focused on beam neutralization by electron sources that were neglected in earlier simulations, including emission from walls and the target, photoionization by the target radiation, and pre-neutralization by a plasma generated along the beam path. When these effects are included in simulations with practicable beam and chamber parameters, the resulting focal spot is approximately the size required by a distributed radiator target.

  14. Method for studying a sample of material using a heavy ion induced mass spectrometer source

    DOE Patents [OSTI]

    Fries, David P. (St. Petersburg, FL); Browning, James F. (Palm Harbour, FL)

    1999-01-01T23:59:59.000Z

    A heavy ion generator is used with a plasma desorption mass spectrometer to provide an appropriate neutron flux in the direction of a fissionable material in order to desorb and ionize large molecules from the material for mass analysis. The heavy ion generator comprises a fissionable material having a high n,f reaction cross section. The heavy ion generator also comprises a pulsed neutron generator that is used to bombard the fissionable material with pulses of neutrons, thereby causing heavy ions to be emitted from the fissionable material. These heavy ions impinge on a material, thereby causing ions to desorb off that material. The ions desorbed off the material pass through a time-of-flight mass analyzer, wherein ions can be measured with masses greater than 25,000 amu.

  15. Deeply virtual Compton scattering at small-$x$ in future Electron - Ion Colliders

    E-Print Network [OSTI]

    Goncalves, V P

    2015-01-01T23:59:59.000Z

    The study of exclusive processes in the future electron-ion ($eA$) colliders will be an important tool to investigate the QCD dynamics at high energies as they are in general driven by the gluon content of the target which is strongly subject to parton saturation effects. In this paper we compute the coherent and incoherent cross sections for the deeply virtual Compton scattering (DVCS) process relying on the color dipole approach and considering different models for the dipole - proton scattering amplitude. The dependencies of the cross sections with the energy, photon virtuality, nuclear mass number and squared momentum transfer are analysed in detail.

  16. Concepts for ELIC - A High Luminosity CEBAF Based Electron-Light Ion Collider

    SciTech Connect (OSTI)

    Ya. Derbenev, A. Bogacz, G. Krafft, R. Li, L. Merminga, B. Yunn, Y. Zhang

    2006-09-01T23:59:59.000Z

    A CEBAF accelerator based electron-light ion collider (ELIC) of rest mass energy from 20 to 65 GeV and luminosity from 10^33 to 10^35 cm6-2s^-1 with both beams polarized is envisioned as a future upgrade to CEBAF. A two step upgrade scenario is under study: CEBAF accelerator-ring-ring scheme (CRR) as the first step, and a multi-turn ERL-ring as the second step, to attain a better electron emittance and maximum luminosity. In this paper we report results of our studies of the CRR version of ELIC.

  17. HIGH ENERGY DENSITY PHYSICS EXPERIMENTS WITH INTENSE HEAVY ION BEAMS

    SciTech Connect (OSTI)

    Bieniosek, F.M.; Henestroza, E.; Leitner, M.; Logan, B.G.; More, R.M.; Roy, P.K.; Ni, P.; Seidl, P.A.; Waldron, W.L.; Barnard, J.J.

    2008-08-01T23:59:59.000Z

    The US heavy ion fusion science program has developed techniques for heating ion-beam-driven warm dense matter (WDM) targets. The WDM conditions are to be achieved by combined longitudinal and transverse space-charge neutralized drift compression of the ion beam to provide a hot spot on the target with a beam spot size of about 1 mm, and pulse length about 1-2 ns. As a technique for heating volumetric samples of matter to high energy density, intense beams of heavy ions are capable of delivering precise and uniform beam energy deposition dE/dx, in a relatively large sample size, and the ability to heat any solid-phase target material. Initial experiments use a 0.3 MeV K+ beam (below the Bragg peak) from the NDCX-I accelerator. Future plans include target experiments using the NDCX-II accelerator, which is designed to heat targets at the Bragg peak using a 3-6 MeV lithium ion beam. The range of the beams in solid matter targets is about 1 micron, which can be lengthened by using porous targets at reduced density. We have completed the fabrication of a new experimental target chamber facility for WDM experiments, and implemented initial target diagnostics to be used for the first target experiments in NDCX-1. The target chamber has been installed on the NDCX-I beamline. The target diagnostics include a fast multi-channel optical pyrometer, optical streak camera, VISAR, and high-speed gated cameras. Initial WDM experiments will heat targets by compressed NDCX-I beams and will explore measurement of temperature and other target parameters. Experiments are planned in areas such as dense electronegative targets, porous target homogenization and two-phase equation of state.

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

    E-Print Network [OSTI]

    Makeev, Andrei

    2001-01-01T23:59:59.000Z

    The work presented here is devoted to research which I have done within the BRAHMS collaboration at Brookhaven National Laboratory in the period from January 1999 until October 2001. The Texas A&M group in the BRAHMS experiment is responsible...

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

    E-Print Network [OSTI]

    Makeev, Andrei

    2001-01-01T23:59:59.000Z

    LIST OF FIGURES FIGURE Page RHIC accelerator facility. Top view of the BRAHMS detectors and magnets. BRAHMS beam-beam counter arrays. The points are particles from GEANT simulations hitting the active detector volumes. . . . 11 Silicon strip... Calculated response of the ZDC to protons, electrons and muons. . . 22 ZDC module-photomultiplier assembly. 24 W-Cherenkov ZDC prototype spectra when hit with 100 and 160 GeV protons at CERN. 26 10 Measured ZDC energy resolution versus energy. 28 Because...

  20. Tests of an RF Dipole Crabbing Cavity for an Electron-Ion Collider

    SciTech Connect (OSTI)

    Castilla Loeza, Alejandro [ODU, JLAB; Delayen, Jean R. [ODU, JLAB

    2013-12-01T23:59:59.000Z

    On the scheme of developing a medium energy electron-ion collider (MEIC) at Jefferson Lab, we have designed a compact superconducting rf dipole cavity at 750 MHz to crab both electron and ion bunches and increase luminosities at the interaction points (IP) of the machine. Following the design optimization and characterization of the electromagnetic properties such as peak surface fields and shunt impedance, along with field nonuniformities, multipole components content, higher order modes (HOM) and multipacting, a prototype cavity was built by Niowave Inc. The 750 MHz prototype crab cavity has been tested at 4 K and is ready for re-testing at 4 K and 2 K at Jefferson Lab. In this paper we present the detailed results of the rf tests performed on the 750 MHz crab cavity prototype.

  1. Stopping and Baryon Transport in Heavy Ion Reactions

    E-Print Network [OSTI]

    F. Videbaek

    2005-05-10T23:59:59.000Z

    In this report I will give an experimental overview on nuclear stopping in hadron collisions, and relate observations to understanding of baryon transport. Baryon number transport is not only evidenced via net-proton distributions but also by the enhancement of strange baryons near mid-rapidity. Although the focus is on high-energy data obtained from pp and heavy ions from RHIC, relevant data from SPS and ISR will be considered. A discussion how the available data at higher energy relates and gives information on baryon junction, quark-diquark breaking will be made.

  2. Thermophoretic Flow in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Thoma, M H

    2001-01-01T23:59:59.000Z

    If a quark-gluon plasma is formed in relativistic heavy-ion collisions, there might be a mixed phase of quarks and gluons and hadronic clusters when the critical temperature is reached in the expansion of the fireball. If there is a temperature gradient in the fireball, the hadronic clusters, embedded in the heat bath of quarks and gluons, are subjected to a thermophoretic force. It is shown that even for small temperature gradients and short lifetimes of the mixed phase thermophoresis leads to a strong flow.

  3. Studies of multiplicity in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    B. B. Back

    2004-11-29T23:59:59.000Z

    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.

  4. Heavy ion fusion science research for high energy density physics and fusion applications

    E-Print Network [OSTI]

    Logan, B.G.

    2007-01-01T23:59:59.000Z

    drive targets for inertial fusion energy. 1. Introduction Adensity matter and fusion energy. Previously, experiments inHeavy ion fusion science research for high energy density

  5. Progress in heavy ion drivers inertial fusion energy: From scaled experiments to the integrated research experiment

    E-Print Network [OSTI]

    2001-01-01T23:59:59.000Z

    ION DRIVEN INERTIAL FUSION ENERGY: FROM SCALED EXPERIMENTSThe promise of inertial fusion energy driven by heavy ionleading to an inertial fusion energy power plant. The focus

  6. Can CP-violation be observed in heavy-ion collisions?

    E-Print Network [OSTI]

    I. B. Khriplovich; A. S. Rudenko

    2011-03-16T23:59:59.000Z

    We demonstrate that, at least at present, there is no convincing way to detect CP-violation in heavy-ion collisions.

  7. Microstructural changes induced by low energy heavy ion irradiation in titanium silicon carbide

    E-Print Network [OSTI]

    Boyer, Edmond

    Microstructural changes induced by low energy heavy ion irradiation in titanium silicon carbide CNRS 6622, Parc Valrose, 06108 Nice cedex 2, France ABSTRACT Low energy ion irradiation was used

  8. RF gas plasma source development for heavy ion fusion

    SciTech Connect (OSTI)

    Ahle, L.E.; Hall, R.P.; Molvik, A.W.

    2002-02-22T23:59:59.000Z

    Presently the Heavy Ion Fusion Virtual National Laboratory is researching ion sources and injector concepts to understand how to optimize beam brightness over a range of currents (50-2000 mA argon equivalent). One concept initially accelerates millimeter size, milliamp beamlets to 1 MeV before merging them into centimeter size, ampere beams. Computer simulations have shown the final brightness of the merged beams is dominated by the emittance growth of the merging process, as long as the beamlets ion temperature is below a few eV. Thus, a RF multicusp source capable of high current density can produce beams with better brightness compared to ones extracted from a colder source with a large aperture and lower current density. As such, experiments have begun to develop a RF multicusp source capable of delivering one amp of extracted beam current. It is expected that it will require 10 kW of 13 MHz RF power delivered via a quartz shielded, one and half turn, four inch diameter antenna. Important considerations in the development of the source include the dependence of current density and beam ion temperature on consumed RF power and gas pressure. A fast rise time ({approx}100 ns) for the extracted beam pulse must also be achieved. Progress on these experiments will be presented.

  9. RF Gas Plasma Source Development for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Ahle, L; Hall, R P; Molvik, A W; Kwan, J W; Leung, K N

    2001-09-04T23:59:59.000Z

    Presently the Heavy Ion Fusion Virtual National Laboratory is researching ion sources and injector concepts to understand how to optimize beam brightness over a range of currents (50-2000 mA argon equivalent). One concept initially accelerates millimeter size, milliamp beamlets to 1 MeV before merging them into centimeter size, ampere beams. Computer simulations have shown the final brightness of the merged beams is dominated by the emittance growth of the merging process, as long as the beamlets ion temperature is below a few eV. Thus, a RF multicusp source capable of high current density can produce beams with better brightness compared to ones extracted from a colder source with a large aperture and lower current density. As such, experiments have begun to develop a RF multicusp source capable of delivering one amp of extracted beam current. It is expected that it will require 10 kW of 13 MHz RF power delivered via a quartz shielded, one and half turn, four inch diameter antenna. Important considerations in the development of the source include the dependence of current density and beam ion temperature on consumed RF power and gas pressure. A fast rise time ({approx} 100 ns) for the extracted beam pulse must also be achieved. Progress on these experiments will be presented.

  10. Simulating Electron Clouds in Heavy-Ion Accelerators

    SciTech Connect (OSTI)

    Cohen, R.H.; Friedman, A.; Kireeff Covo, M.; Lund, S.M.; Molvik,A.W.; Bieniosek, F.M.; Seidl, P.A.; Vay, J-L.; Stoltz, P.; Veitzer, S.

    2005-04-07T23:59:59.000Z

    Contaminating clouds of electrons are a concern for most accelerators of positive-charged particles, but there are some unique aspects of heavy-ion accelerators for fusion and high-energy density physics which make modeling such clouds especially challenging. In particular, self-consistent electron and ion simulation is required, including a particle advance scheme which can follow electrons in regions where electrons are strongly-, weakly-, and un-magnetized. They describe their approach to such self-consistency, and in particular a scheme for interpolating between full-orbit (Boris) and drift-kinetic particle pushes that enables electron time steps long compared to the typical gyro period in the magnets. They present tests and applications: simulation of electron clouds produced by three different kinds of sources indicates the sensitivity of the cloud shape to the nature of the source; first-of-a-kind self-consistent simulation of electron-cloud experiments on the High-Current Experiment (HCX) at Lawrence Berkeley National Laboratory, in which the machine can be flooded with electrons released by impact of the ion beam and an end plate, demonstrate the ability to reproduce key features of the ion-beam phase space; and simulation of a two-stream instability of thin beams in a magnetic field demonstrates the ability of the large-timestep mover to accurately calculate the instability.

  11. Uniformity of fuel target implosion in Heavy Ion Fusion

    E-Print Network [OSTI]

    Kawata, S; Suzuki, T; Karino, T; Barada, D; Ogoyski, A I; Ma, Y Y

    2015-01-01T23:59:59.000Z

    In inertial confinement fusion the target implosion non-uniformity is introduced by a driver beams' illumination non-uniformity, a fuel target alignment error in a fusion reactor, the target fabrication defect, et al. For a steady operation of a fusion power plant the target implosion should be robust against the implosion non-uniformities. In this paper the requirement for the implosion uniformity is first discussed. The implosion uniformity should be less than a few percent. A study on the fuel hotspot dynamics is also presented and shows that the stagnating plasma fluid provides a significant enhancement of vorticity at the final stage of the fuel stagnation. Then non-uniformity mitigation mechanisms of the heavy ion beam (HIB) illumination are also briefly discussed in heavy ion inertial fusion (HIF). A density valley appears in the energy absorber, and the large-scale density valley also works as a radiation energy confinement layer, which contributes to a radiation energy smoothing. In HIF a wobbling he...

  12. Pulsed, Inductively Generated, Streaming Plasma Ion Source for Heavy Ion Fusion Linacs

    SciTech Connect (OSTI)

    Steven C. Glidden; Howard D Sanders; John B. Greenly; Daniel L. Dongwoo

    2006-04-28T23:59:59.000Z

    This report describes a compact, high current density, pulsed ion source, based on electrodeless, inductively driven gas breakdown, developed to meet the requirements on normalized emittance, current density, uniformity and pulse duration for an ion injector in a heavy-ion fusion driver. The plasma source produces >10 ?s pulse of Argon plasma with ion current densities >100 mA/cm2 at 30 cm from the source and with strongly axially directed ion energy of about 80 eV, and sub-eV transverse temperature. The source has good reproducibility and spatial uniformity. Control of the current density during the pulse has been demonstrated with a novel modulator coil method which allows attenuation of the ion current density without significantly affecting the beam quality. This project was carried out in two phases. Phase 1 used source configurations adapted from light ion sources to demonstrate the feasibility of the concept. In Phase 2 the performance of the source was enhanced and quantified in greater detail, a modulator for controlling the pulse shape was developed, and experiments were conducted with the ions accelerated to >40 kV.

  13. The high current transport experiment for heavy ion inertial fusion

    SciTech Connect (OSTI)

    Prost, L.R.; Baca, D.; Bieniosek, F.M.; Celata, C.M.; Faltens, A.; Henestroza, E.; Kwan, J.W.; Leitner, M.; Seidl, P.A.; Waldron, W.L.; Cohen, R.; Friedman, A.; Grote, D.; Lund, S.M.; Molvik, A.W.; Morse, E.

    2004-05-01T23:59:59.000Z

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program to explore heavy-ion beam transport at a scale representative of the low-energy end of an induction linac driver for fusion energy production. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx} 0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss, even though the initial beam distribution is not ideal (but the emittance is low) nor in thermal equilibrium. We achieved good envelope control, and rematching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  14. Prompt dimuons and D meson production in heavy-ion collisions at the SPS

    E-Print Network [OSTI]

    B. Lenkeit; NA60-Collaboration

    2001-08-14T23:59:59.000Z

    NA60, a follow-up of NA38/50 at the CERN-SPS, is a third generation heavy-ion experiment finally approved in November 2000 for heavy-ion runs in 2002 and 2003. This article will report about the main motivations which lead to this experiment, the main detector concept and the foreseen physics performance.

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

    E-Print Network [OSTI]

    Li, Ba0-An; Ko, Che Ming.

    1995-01-01T23:59:59.000Z

    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. We then show...

  16. Electron Ion Collider: The Next QCD Frontier - Understanding the glue that binds us all

    E-Print Network [OSTI]

    A. Accardi; J. L. Albacete; M. Anselmino; N. Armesto; E. C. Aschenauer; A. Bacchetta; D. Boer; W. K. Brooks; T. Burton; N. -B. Chang; W. -T. Deng; A. Deshpande; M. Diehl; A. Dumitru; R. Dupré; R. Ent; S. Fazio; H. Gao; V. Guzey; H. Hakobyan; Y. Hao; D. Hasch; R. Holt; T. Horn; M. Huang; A. Hutton; C. Hyde; J. Jalilian-Marian; S. Klein; B. Kopeliovich; Y. Kovchegov; K. Kumar; K. Kumeri?ki; M. A. C. Lamont; T. Lappi; J. -H. Lee; Y. Lee; E. M. Levin; F. -L. Lin; V. Litvinenko; T. W. Ludlam; C. Marquet; Z. -E. Meziani; R. McKeown; A. Metz; R. Milner; V. S. Morozov; A. H. Mueller; B. Müller; D. Müller; P. Nadel-Turonski; H. Paukkunen; A. Prokudin; V. Ptitsyn; X. Qian; J. -W. Qiu; M. Ramsey-Musolf; T. Roser; F. Sabatié; R. Sassot; G. Schnell; P. Schweitzer; E. Sichtermann; M. Stratmann; M. Strikman; M. Sullivan; S. Taneja; T. Toll; D. Trbojevic; T. Ullrich; R. Venugopalan; S. Vigdor; W. Vogelsang; C. Weiss; B. -W. Xiao; F. Yuan; Y. -H. Zhang; L. Zheng

    2014-11-30T23:59:59.000Z

    This White Paper presents the science case of an Electron-Ion Collider (EIC), focused on the structure and interactions of gluon-dominated matter, with the intent to articulate it to the broader nuclear science community. It was commissioned by the managements of Brookhaven National Laboratory (BNL) and Thomas Jefferson National Accelerator Facility (JLab) with the objective of presenting a summary of scientific opportunities and goals of the EIC as a follow-up to the 2007 NSAC Long Range plan. This document is a culmination of a community-wide effort in nuclear science following a series of workshops on EIC physics and, in particular, the focused ten-week program on "Gluons and quark sea at high energies" at the Institute for Nuclear Theory in Fall 2010. It contains a brief description of a few golden physics measurements along with accelerator and detector concepts required to achieve them, and it benefited from inputs from the users' communities of BNL and JLab. This White Paper offers the promise to propel the QCD science program in the U.S., established with the CEBAF accelerator at JLab and the RHIC collider at BNL, to the next QCD frontier.

  17. SYSTEMATIC STUDIES OF HEAVY ION COLLISIONS TO SEARCH FOR QUARK-GLUON PLASMA

    SciTech Connect (OSTI)

    Fuqiang Wang

    2007-11-29T23:59:59.000Z

    This is the final technical report for DOE Outstanding Junior Investigator (OJI) Award, 'Systematic Studies of Heavy Ion Collisions to Search for Quark-Gluon Plasma', grant DE-FG02-02ER41219, Principal Investigator (PI) Fuqiang Wang. The research under the grant was divided into two phases. The first concentrated on systematic studies of soft hadron production at low transverse momentum (p{sub T}), in particular the production of (anti-)baryon and strangeness in heavy ion collisions at RHIC energies. The second concentrated on measurements of di-hadron and multi-hadron jet-correlations and investigations of medium response to jets. The research was conducted at the Relativistic Heavy-Ion Collider (RHIC) at BNL with the Solenoidal Tracker At RHIC (STAR) experiment. The total grant is $214,000. The grant established a PC farm solely used for this research. The PC farm consists of 8 nodes with a total of 16 CPUs and 3 disk servers of total 2 TB shared storage. The current balance of the grant is $19,985. The positive balance is because an initial purchase of $22,600 for the PC farm came out of the PI's start-up fund due to the lateness of the award. The PC farm is an integral part of the Purdue Physics Department's computer cluster. The grant supported two Ph.D. graduate students. Levente Molnar was supported from July 2002 to December 2003, and worked on soft hadron production. His thesis title is Systematics of Identified Particle Production in pp, d-Au and Au-Au Collisions at RHIC Energies. He graduated in 2006 and now is a Postdoctoral fellow at INFN Sezione di Bari, Italy working on the ALICE experiment at the LHC. Jason Ulery was supported from January 2004 to July 2007. His thesis title is Two- and Three-Particle Jet-Like Correlations. He defended his thesis in October 2007 and is moving to Frankfurt University, Germany to work on the ALICE experiment at the LHC. The research by this grant resulted in 7 journal publications (2 PRL, 1 PLB, 1 PRC, 2 submitted and 1 in preparation), and 14 invited talks and 10 contributed talks at major conferences. These are listed at end of this report.

  18. Recent Progress on Design Studies of High-Luminosity Ring-Ring Electron-Ion Collider at CEBAF

    SciTech Connect (OSTI)

    Zhang, Y; Bruell, A; Chevtsov, P; Derbenev, Y S; Ent, R; Krafft, G A; Li, R; Merminga, L

    2009-05-01T23:59:59.000Z

    The conceptual design of a ring-ring electron-ion collider based on CEBAF has been continuously optimized to cover a wide center-of-mass energy region and to achieve high luminosity and polarization to support next generation nuclear science programs. Here, we summarize the recent design improvements and R&D progress on interaction region optics with chromatic aberration compensation, matching and tracking of electron polarization in the Figure-8 ring, beam-beam simulations and ion beam cooling studies.

  19. Determining the density dependence of the nuclear symmetry energy using heavy-ion reactions

    E-Print Network [OSTI]

    Lie-Wen Chen; Che Ming Ko; Bao-An Li; Gao-Chan Yong

    2007-11-12T23:59:59.000Z

    We review recent progress in the determination of the subsaturation density behavior of the nuclear symmetry energy from heavy-ion collisions as well as the theoretical progress in probing the high density behavior of the symmetry energy in heavy-ion reactions induced by high energy radioactive beams. We further discuss the implications of these results for the nuclear effective interactions and the neutron skin thickness of heavy nuclei.

  20. Isotropization from Color Field Condensate in heavy ion collisions

    E-Print Network [OSTI]

    Stefan Floerchinger; Christof Wetterich

    2014-08-27T23:59:59.000Z

    The expanding fireball shortly after a heavy ion collision may be qualitatively described by a condensate of color fields or gluons which is analogous to Bose-Einstein-condensation for massive bosonic particles. This condensate is a transient non-equilibrium phenomenon and breaks Lorentz-boost symmetry. The dynamics of color field condensates involves collective excitations and is rather different from the perturbative scattering of gluons. In particular, it provides for an efficient mechanism to render the local pressure approximately isotropic after a short time of 0.2 fm/c. We suggest that an isotropic color field condensate may play a central role for a simple description of prethermalization and isotropization in the early stages of the collision.

  1. Can quark effects be observed in intermediate heavy ion collisions?

    E-Print Network [OSTI]

    D. T. da Silva; D. Hadjimichef

    2003-09-18T23:59:59.000Z

    In recent years a tentative description of the short-range part of hadron interactions with constituent quark interchange has been developed providing an alternative approach to meson physics. Quark interchange plays a role, for example, in the nucleon-nucleon ($NN$) phase-shifts and cross-section. In heavy ion collision simulations at intermediate energies one of the main features is the $NN$ cross-section in the collisional term, where in most cases it is an input adjusted to the free space value. In this paper we introduce the quark degrees of freedom to the $NN$ cross-section in the Vlasov-Uehling-Uhlenbeck (VUU) model and explore the possibility that these effects appear in the observables at lower energies.

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

    E-Print Network [OSTI]

    B. B. Back

    2005-08-15T23:59:59.000Z

    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.

  3. Pion and photon production in heavy ion collisions

    E-Print Network [OSTI]

    G. David

    2009-03-02T23:59:59.000Z

    Measurement of neutral pions and direct photons are closely connected experimentally, on the other hand they probe quite different aspects of relativistic heavy ion collisions. In this short review of the $\\pi^0$ results from the PHENIX experiment at RHIC our focus is on the $\\phi$-integrated nuclear modification factor, its energy and system size dependence, and the impact of these results on parton energy loss models. We also discuss the current status of high $p_T$ and thermal direct photon measurements both in $p$ + $p$ and Au+Au collisions. Recognizing the advantages of measuring not only the "signal", but also all the "references" needed for proper interpretation in the same experiments (with same or similar systematics) we argue that RHIC should regularly include $d$ + A and even $d$ + $d$ collisions into its system size and energy scan.

  4. Net-proton probability distribution in heavy ion collisions

    E-Print Network [OSTI]

    P. Braun-Munzinger; B. Friman; F. Karsch; K. Redlich; V. Skokov

    2011-07-21T23:59:59.000Z

    We compute net-proton probability distributions in heavy ion collisions within the hadron resonance gas model. The model results are compared with data taken by the STAR Collaboration in Au-Au collisions at sqrt(s_{NN})= 200 GeV for different centralities. We show that in peripheral Au-Au collisions the measured distributions, and the resulting first four moments of net-proton fluctuations, are consistent with results obtained from the hadron resonance gas model. However, data taken in central Au-Au collisions differ from the predictions of the model. The observed deviations can not be attributed to uncertainties in model parameters. We discuss possible interpretations of the observed deviations.

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

    SciTech Connect (OSTI)

    Magas, V. K.; Csernai, L. P. (László P.); Keranen, A.; Manninen, J.; Strottman, D. D. (Daniel D.)

    2002-01-01T23:59:59.000Z

    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.

  6. Recirculating induction accelerators as drivers for heavy ion fusion

    SciTech Connect (OSTI)

    Barnard, J.J.; Deadrick, F.; Friedman, A.; Grote, D.P.; Griffith, L.V.; Kirbie, H.C.; Neil, V.K.; Newton, M.A.; Paul, A.C.; Sharp, W.M.; Shay, H.D. (Lawrence Livermore National Laboratory, Livermore, California 94550 (United States)); Bangerter, R.O.; Faltens, A.; Fong, C.G.; Judd, D.L.; Lee, E.P.; Reginato, L.L.; Yu, S.S. (Lawrence Berkeley Laboratory, Berkeley, California 94720 (United States)); Godlove, T.F. (FM Technologies, Inc., 10529-B Braddock Rd., Fairfax, Virginia 22302 (United States))

    1993-07-01T23:59:59.000Z

    A two-year study of recirculating induction heavy ion accelerators as low-cost driver for inertial-fusion energy applications was recently completed. The projected cost of a 4 MJ accelerator was estimated to be about $500 M (million) and the efficiency was estimated to be 35%. The principal technology issues include energy recovery of the ramped dipole magnets, which is achieved through use of ringing inductive/capacitive circuits, and high repetition rates of the induction cell pulsers, which is accomplished through arrays of field effect transistor (FET) switches. Principal physics issues identified include minimization of particle loss from interactions with the background gas, and more demanding emittance growth and centroid control requirements associated with the propagation of space-charge-dominated beams around bends and over large path lengths. In addition, instabilities such as the longitudinal resistive instability, beam-breakup instability and betatron-orbit instability were found to be controllable with careful design.

  7. Design study of a DPIS injector for a heavy ion FFAG

    SciTech Connect (OSTI)

    Okamura,M.; Raparia, D.; Ishibashi, K.; Yonemura, Y.; Kanesue, T.

    2008-09-29T23:59:59.000Z

    A new heavy ion injector linac is proposed for providing heavy ion beams to a fixed field alternating gradient (FFAG) accelerator in Kyushu University. A combination of the new intense laser source based injector and the FFAG will be able to accelerate high current ion beams with 100 Hz of a repetition rate. The planned average current reaches 7 {micro}A with carbon 6+ beam.

  8. Workshop on Accelerators for Heavy Ion Fusion: Summary Report of the Workshop

    SciTech Connect (OSTI)

    Seidl, P.A.; Barnard, J.J.

    2011-04-29T23:59:59.000Z

    The Workshop on Accelerators for Heavy Ion Fusion was held at Lawrence Berkeley National Laboratory May 23-26, 2011. The workshop began with plenary sessions to review the state of the art in HIF (heavy ion fusion), followed by parallel working groups, and concluded with a plenary session to review the results. There were five working groups: IFE (inertial fusion energy) targets, RF approach to HIF, induction accelerator approach to HIF, chamber and driver interface, ion sources and injectors.

  9. A Scaled Final Focus Experiment for Heavy Ion Fusion

    SciTech Connect (OSTI)

    MacLaren, Stephan, Alexander

    2000-09-19T23:59:59.000Z

    A one-tenth dimensionally scaled version of a final focus sub-system design for a heavy ion fusion driver is built and tested. By properly scaling the physics parameters that relate particle energy and mass, beam current, beam emittance, and focusing field, the transverse dynamics of a driver scale final focus are replicated in a small laboratory beam. The experiment uses a 95 {micro}A beam of 160 keV Cs{sup +} ions to study the dynamics as the beam is brought to a ballistic focus in a lattice of six quadrupole magnets. Diagnostic stations along the experiment track the evolution of the transverse phase space of the beam. The measured focal spot size is consistent with calculations and the report of the design on which the experiment is based. By uniformly varying the strengths of the focusing fields in the lattice, the chromatic effect of a small energy deviation on the spot size can be reproduced. This is done for {+-}1% and {+-}2% shifts and the changes in the focus are measured. Additionally, a 400 {micro}A beam is propagated through the experiment and partially neutralized after the last magnet using electrons released from a hot tungsten filament. The increase in beam current allows for the observation of significant effects on both the size and shape of the focal spot when the electrons are added.

  10. Proceedings of the 8th High Energy Heavy Ion Study

    E-Print Network [OSTI]

    Harris Ed, J.W.

    2010-01-01T23:59:59.000Z

    and a high pressure ion chamber. Several of the gas modulesenergy measurement in the ion chamber. The calibrations werefield Frisch grid ion chamber, which is operated with

  11. Analytical and numerical studies of heavy ion beam transport in the fusion chamber

    E-Print Network [OSTI]

    Kaganovich, Igor

    Analytical and numerical studies of heavy ion beam transport in the fusion chamber IGOR D to acceptable levels. During ion beam propagation in the chamber, electrons are drawn into the beam, Princeton, New Jersey 08543, USA Abstract The propagation of a high-current finite-length ion charge bunch

  12. 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.

    2009-01-01T23:59:59.000Z

    s quarks up to p(T) similar to 4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, R(dAu), for the phi meson increases above unity at intermediate p(T), similar to that for pions and protons, while R...

  13. 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.

    2009-01-01T23:59:59.000Z

    ,6 L. C. 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...

  14. Atomic nuclei decay modes by spontaneous emission of heavy ions

    SciTech Connect (OSTI)

    Poenaru, D.N.; Ivascu, M.; Sndulescu, A.; Greiner, W.

    1985-08-01T23:59:59.000Z

    The great majority of the known nuclides with Z>40, including the so-called stable nuclides, are metastable with respect to several modes of spontaneous superasymmetric splitting. A model extended from the fission theory of alpha decay allows one to estimate the lifetimes and the branching ratios relative to the alpha decay for these natural radioactivities. From a huge amount of systematic calculations it is concluded that the process should proceed with maximum intensity in the trans-lead nuclei, where the minimum lifetime is obtained from parent-emitted heavy ion combinations leading to a magic (/sup 208/Pb) or almost magic daughter nucleus. More than 140 nuclides with atomic number smaller than 25 are possible candidates to be emitted from heavy nuclei, with half-lives in the range of 10/sup 10/--10/sup 30/ s: /sup 5/He, /sup 8en-dash10/Be, /sup 11,12/B, /sup 12en-dash16/C, /sup 13en-dash17/N, /sup 15en-dash22/O, /sup 18en-dash23/F, /sup 20en-dash26/Ne, /sup 23en-dash28/Na, /sup 23en-dash30/Mg, /sup 27en-dash32/Al, /sup 28en-dash36/Si, /sup 31en-dash39/P, /sup 32en-dash42/S, /sup 35en-dash45/Cl, /sup 37en-dash47/Ar, /sup 40en-dash49/ K, . .Ca, /sup 44en-dash53/ Sc, /sup 46en-dash53/Ti, /sup 48en-dash54/V, and /sup 49en-dash55/ Cr. The shell structure and the pairing effects are clearly manifested in these new decay modes.

  15. A power-law description of heavy ion collision centrality

    E-Print Network [OSTI]

    Thomas A. Trainor; Duncan J. Prindle

    2007-01-30T23:59:59.000Z

    The minimum-bias distribution on heavy ion collision multiplicity $n_{ch}$ is well approximated by power-law form $n_{ch}^{-3/4}$, suggesting that a change of variable to $n_{ch}^{1/4}$ may provide more precise access to the structure of the distribution and to A-A collision centrality. We present a detailed centrality study of Hijing-1.37 Monte Carlo data at 200 GeV using the power-law format. We find that the minimum-bias distribution on $n_{participant}^{1/4}$, determined with a Glauber Monte Carlo simulation, is uniform except for a 5% sinusoidal variation. The power-law format reveals precise linear relations between Glauber parameters $n_{part}$ and $n_{bin}$ and the fractional cross section. The power-law format applied to RHIC data facilitates incorporation of extrapolation constraints on data and Glauber distributions to obtain a ten-fold improvement in centrality accuracy for peripheral collisions.

  16. Baryon Annihilation and Regeneration in Heavy Ion Collisions

    E-Print Network [OSTI]

    Yinghua Pan; Scott Pratt

    2014-04-16T23:59:59.000Z

    The role of baryon-antibaryon annihilation during the hadronic stage of a relativistic heavy ion collision is explored by simulating the chemical evolution of a hadron gas. Beginning with a chemically equilibrated gas at an initial temperature of 170 MeV, the chemical composition of a representative hydrodynamic cell is followed throughout the hadronic stage. The cell's volume changes with time according to a parameterization that mimics a three-dimensional hydrodynamic expansion. The chemical evolution includes both annihilation and regeneration of baryons, consistent with detailed balance. During the hadronic stage, the number of baryons drops by approximately $40\\%$ for the case where there is no net baryonic charge. When the calculations are performed without the baryon regenerating processes, e.g. $5\\pi\\rightarrow p\\bar{p}$, the loss of baryons was found to be closer to $50\\%$. After accounting for annihilation, yields are consistent with measurements from the ALICE Collaboration at the LHC. Baryon annihilation is shown to alter the extracted chemical breakup temperature by significantly changing the $p/\\pi$ ratio. Assuming that annihilation cross sections are independent of the strangeness and isospin of the annihilating baryon and anti-baryon, the loss of strange baryons from annihilation is found to be similar.

  17. Hydro-kinetic approach to relativistic heavy ion collisions

    E-Print Network [OSTI]

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

    2008-08-28T23:59:59.000Z

    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. Fifth high-energy heavy-ion study

    SciTech Connect (OSTI)

    Not Available

    1981-10-01T23:59:59.000Z

    This was the fifth of a continuing series of summer studies held at LBL to discuss high energy heavy ion collisions. Recently, a similar meeting has been held on alternate years at GSI (Darmstadt); and, in 1979, we held a meeting at LBL exclusively devoted to ultra-relativistic nuclear collisions. Two new features distinguish this study from earlier meetings in the series. First, the energy range for discussion was broadened by including collisions from about 20 MeV/nucleon to the highest available in the cosmic radiation. The lower range, particularly below 100 MeV/nucleon, will be under intense study in the near future with machines such as the upgraded Bevalac, Michigan State University Superconducting Cyclotron, GANIL in France, and the SC at CERN. Recently, the high energy collision regime has been expanded by the successful operation of the CERN ISR with alpha particles. Second, in addition to an extensive program of invited talks, we decided for the first time to actively solicit contributions. Forty-seven individual items from the conference were prepared separately for the data base. (GHT)

  19. Centrality dependence of strangeness production in heavy-ion collisions as a geometrical effect of core-corona superposition

    E-Print Network [OSTI]

    F. Becattini; J. Manninen

    2008-11-23T23:59:59.000Z

    It is shown that data on strange particle production as a function of centrality in Au-Au collisions at \\sqrt(s)_{NN}= 200 GeV can be explained with a superposition of emission from a hadron gas at full chemical equilibrium (core) and from nucleon-nucleon collisions at the boundary (corona) of the overlapping region of the two colliding nuclei. This model nicely accounts for the enhancement of phi meson and strange particle production as a function of centrality observed in relativistic heavy ion collisions at that energy. The enhancement is mainly a geometrical effect, that is the increasing weight of the core with respect to corona for higher centrality, while strangeness canonical suppression in the core seems to play a role only in very peripheral collisions. This model, if confirmed at lower energy, would settle the long-standing problem of strangeness under-saturation in relativistic heavy ion collisions, parametrized by $\\gs$. Furthermore, it would give a unique tool to locate the onset of deconfinement in nuclear collisions both as a function of energy and centrality if this is to be associated to the onset of the formation of a fully equilibrated core.

  20. Microscopic Calculation of Pre-Compound Excitation Energies for Heavy-Ion Collisions

    E-Print Network [OSTI]

    A. S. Umar; V. E. Oberacker; J. A. Maruhn; P. -G. Reinhard

    2009-09-18T23:59:59.000Z

    We introduce a microscopic approach for calculating the excitation energies of systems formed during heavy-ion collisions. The method is based on time-dependent Hartree-Fock (TDHF) theory and allows the study of the excitation energy as a function of time or ion-ion separation distance. We discuss how this excitation energy is related to the estimate of the excitation energy using the reaction $Q$-value, as well as its implications for dinuclear pre-compound systems formed during heavy-ion collisions.

  1. DESIGN/COST STUDY OF AN INDUCTION LINAC FOR HEAVY IONS FOR PELLET-FUSION

    E-Print Network [OSTI]

    Faltens, A.

    2010-01-01T23:59:59.000Z

    LINAC FOR HEAVY IONS FOR PELLET-FUSION* Andris Faltens. EgonContract The physics of the pellet implosion sets strin-deposition in the pellet > 20 MJ/g. Thus, considerable

  2. Medium Effects on Kaon and Antikaon Spectra in Heavy-Ion Collisions 

    E-Print Network [OSTI]

    Fang, X. S.; Ko, Che Ming; Brown, G. E.; Koch, V.

    1993-01-01T23:59:59.000Z

    transport model, it is found that the slope parameter of the kaon kinetic energy distribution is larger than that of the antikaon. This is consistent with the experimental data from heavy-ion collisions in the Alternating Gradient Synchrotron experiments...

  3. 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.

    2011-01-01T23:59:59.000Z

    upsilon(2) of J/psi in relativistic heavy-ion collisions. For the expansion dynamics of produced hot, dense matter, we introduce a schematic fireball model with its transverse acceleration determined from the pressure gradient inside the fireball...

  4. A Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHC Energies

    E-Print Network [OSTI]

    2008-01-01T23:59:59.000Z

    A Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHCf CERN, Abstract Standard jet ?nding techniques used indescribes a modi?ed cone-type jet ?nding algorithm developed

  5. Self-pinched beam transport experiments Relevant to Heavy Ion Driven inertial fusion energy

    E-Print Network [OSTI]

    1998-01-01T23:59:59.000Z

    C. L . Olson, J. Fusion Energy 1, 309 (1982). "FilamentationHeavy Ion Driven Inertial Fusion Energy January 30, 1998 W.Agency Sixteenth I A E A Fusion Energy Conference (Montreal,

  6. Response of Nanocrystalline 3C Silicon Carbide to Heavy-Ion Irradiatio...

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

    Citation: Jiang W, H Wang, I Kim, IT Bae, G Li, P Nachimuthu, Z Zhu, Y Zhang, and WJ Weber.2009."Response of Nanocrystalline 3C Silicon Carbide to Heavy-Ion...

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

    E-Print Network [OSTI]

    Wenger, Edward (Edward Allen)

    2008-01-01T23:59:59.000Z

    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 ...

  8. asymmetric heavy-ion collisions: Topics by E-print Network

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

    generation of jet reconstruction algorithms which are also applicable in the heavy ion environment. We review the latest results on jet-medium interactions as seen in A+A...

  9. Generation, transport and focusing of high-brightness heavy ion beams

    E-Print Network [OSTI]

    Henestroza, Enrique

    2006-01-01T23:59:59.000Z

    The Neutralized Transport Experiment (NTX) has been built at the Heavy Ion Fusion Virtual National Laboratory. NTX is the first successful integrated beam system experiment that explores various physical phenomena, and ...

  10. Silica coated magnetite nanoparticles for removal of heavy metal ions from polluted waters

    E-Print Network [OSTI]

    Dash, Monika

    2013-01-01T23:59:59.000Z

    Magnetic removal of Hg2+ and other heavy metal ions like Cd2+, Pb2+ etc. using silica coated magnetite particles from polluted waters is a current topic of active research to provide efficient water recycling and long term high quality water. The technique used to study the bonding characteristics of such kind of nanoparticles with the heavy metal ions is a very sensitive hyperfine specroscopy technique called the perturbed angular correlation technique (PAC).

  11. Recent results from the UrQMD hybrid model for heavy ion collisions

    E-Print Network [OSTI]

    Bleicher, Marcus; Steinheimer, Jan; van Hees, Hendrik

    2015-01-01T23:59:59.000Z

    These proceedings present recent results from transport-hydrodynamics-hybrid models for heavy ion collisions at relativistic energies. The main focus is on the absorption of (anti-)protons in the hadronic afterburner stage of the reaction, di-lepton production at SPS and heavy quark dynamics.

  12. COULOMB EFFECTS ON PIONS PRODUCED IN HEAVY ION REACTIONS

    E-Print Network [OSTI]

    Sullivan, J.P.

    2010-01-01T23:59:59.000Z

    singles other rates ion chamber, and secondary beam monitorswitn an Ar/CO- filled ion chamber) and the solid-anglementioned Ar/C0„-filled ion chamber. To minimize background

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

    E-Print Network [OSTI]

    M. J. Tannenbaum

    2006-07-28T23:59:59.000Z

    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.

  14. Characterization of an RF-Driven Plasma Ion Source for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Westenskow, G A; Hall, R P; Halaxa, E; Kwan, J W

    2003-05-13T23:59:59.000Z

    We are testing a high-current-density high-brightness Argon-Ion Source for Heavy Ion Fusion applications. The 100-kV 20-{micro}s source has produced up to 5 mA of Ar{sup +} in a single beamlet. The extraction current density is 100 mA/cm2. We have measured the emittance of the beamlet, and the fraction of Ar{sup ++} ions under several operating conditions. We present measurements of the extracted current density as a function of RF power and gas pressure ({approx} 2 mT), current density uniformity, and energy dispersion (due to charge exchange). We are testing a 80-kV 61-hole multi-beamlet array that will produce a total current > 200 mA. In the current experiments the beamlets are not merged into a single beam. A 500-kV experiment where the beamlets will be merged to a produce 0.5-A beam is being planned.

  15. Final Progress Report - Heavy Ion Accelerator Theory and Simulation

    SciTech Connect (OSTI)

    Haber, Irving

    2009-10-31T23:59:59.000Z

    The use of a beam of heavy ions to heat a target for the study of warm dense matter physics, high energy density physics, and ultimately to ignite an inertial fusion pellet, requires the achievement of beam intensities somewhat greater than have traditionally been obtained using conventional accelerator technology. The research program described here has substantially contributed to understanding the basic nonlinear intense-beam physics that is central to the attainment of the requisite intensities. Since it is very difficult to reverse intensity dilution, avoiding excessive dilution over the entire beam lifetime is necessary for achieving the required beam intensities on target. The central emphasis in this research has therefore been on understanding the nonlinear mechanisms that are responsible for intensity dilution and which generally occur when intense space-charge-dominated beams are not in detailed equilibrium with the external forces used to confine them. This is an important area of study because such lack of detailed equilibrium can be an unavoidable consequence of the beam manipulations such as acceleration, bunching, and focusing necessary to attain sufficient intensity on target. The primary tool employed in this effort has been the use of simulation, particularly the WARP code, in concert with experiment, to identify the nonlinear dynamical characteristics that are important in practical high intensity accelerators. This research has gradually made a transition from the study of idealized systems and comparisons with theory, to study the fundamental scaling of intensity dilution in intense beams, and more recently to explicit identification of the mechanisms relevant to actual experiments. This work consists of two categories; work in direct support beam physics directly applicable to NDCX and a larger effort to further the general understanding of space-charge-dominated beam physics.

  16. Shielding analysis for a heavy ion beam chamber with plasma channels for ion transport

    SciTech Connect (OSTI)

    Sawan, M.E.; Peterson, R.R.; Yu, S.

    2000-06-28T23:59:59.000Z

    Neutronics analysis has been performed to assess the shielding requirements for the insulators and final focusing magnets in a modified HYLIFE-II target chamber that utilizes pre-formed plasma channels for heavy ion beam transport. Using 65 cm thick Flibe jet assemblies provides adequate shielding for the electrical insulator units. Additional shielding is needed in front of the final focusing superconducting quadrupole magnets. A shield with a thickness varying between 45 and 90 cm needs to be provided in front of the quadrupole unit. The final laser mirrors located along the channel axis are in the direct line-of-sight of source neutrons. Neutronics calculations were performed to determine the constraints on the placement of these mirrors to be lifetime components.

  17. Electrical conductivity of the quark-gluon plasma and soft photon spectrum in heavy-ion collisions

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

    Yin, Yi [University of Illinois, Physics Dept., IL (United States); Brookhaven National Laboratory, Physics Department, Upton, NY (United States)

    2014-10-01T23:59:59.000Z

    I extract the electrical conductivity ?0 of the quark gluon plasma (QGP) and study the effects of magnetic field and chiral anomaly on soft photon azimuthal anisotropy, v?, based on the thermal photon spectrum at 0.4GeVHeavy Ion Collider energy. As a basis for my analysis, I derive the behavior of retarded photon self-energy of a strongly interacting neutral plasma in hydrodynamic regime in the presence of magnetic field and chiral anomaly. By evolving the resulting soft thermal photon production rate over the realistic hydrodynamic background and comparing the results with the data from the PHENIX Collaboration, I found that the electrical conductivity at QGP temperature is in the range: 0.4Collider, the chiral magnetic wave would give negative contribution to photon v?.

  18. Systematics of cross sections for target K-vacancy production in heavy ion collisions

    E-Print Network [OSTI]

    Peng, Yong

    2007-04-25T23:59:59.000Z

    Cross sections for K-shell ionization by heavy ions have been determined from the measurements of target K x-ray yields. The measurements were performed with Ar, Kr, and Xe ions at energies from 2.5 to 25 MeV/amu and self-supported metallic foil...

  19. High energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from

    E-Print Network [OSTI]

    in inter- action processes of short and ultra-short laser pulses with matter. Ion generation from laserHigh energy heavy ion jets emerging from laser plasma generated by long pulse laser beams from the NHELIX laser system at GSI G. SCHAUMANN,1 M.S. SCHOLLMEIER,1 G. RODRIGUEZ-PRIETO,2 A. BLAZEVIC,2 E

  20. Simultaneous Heavy Flavor Fractions and Top Cross Section Measurement at the Collider Detector at Fermilab

    SciTech Connect (OSTI)

    Mathis, Mark J.; /Johns Hopkins U.

    2010-04-01T23:59:59.000Z

    This dissertation describes the measurement of the top pair production cross section, using data from proton-antiproton collisions at a center-of-mass energy of 1.96 TeV, with 2.7 {+-} 0.2 fb{sup -1} of data collected by the Collider Detector at Fermilab. Background contributions are measured concurrently with the top cross section in the b-tagged lepton-plus-jets sample using a kinematic fit, which simultaneously determines the cross sections and normalizations of t{bar t}, W + jets, QCD, and electroweak processes. This is the first application of a procedure of this kind. The top cross section is measured to be {sigma}{sub t{bar t}} = 7.64 {+-} 0.57(stat + syst) {+-} 0.45(lumi) pb and the Monte Carlo simulation scale factors K{sub Wb{bar b}} = 1.57 {+-} 0.25, K{sub Wc{bar c}} = 0.94 {+-} 0.79, K{sub Wc} = 1.9 {+-} 0.3, and K{sub Wq{bar q}} = 1.1 {+-} 0.3. These results are consistent with existing measurements using other procedures. More data will reduce the systematic uncertainties and will lead to the most precise of any single analysis to date.

  1. Measurements of phi meson production in relativistic heavy-ion collisions at RHIC

    SciTech Connect (OSTI)

    STAR Coll

    2009-06-16T23:59:59.000Z

    We present results for the measurement of {phi} meson production via its charged kaon decay channel {phi} {yields} K{sup +}K{sup -} in Au + Au collisions at {radical}s{sub NN} = 62.4, 130, and 200 GeV, and in p + p and d + Au collisions at {radical}s{sub NN} = 200 GeV from the STAR experiment at the BNL Relativistic Heavy Ion Collider (RHIC). The midrapidity (|y| < 0.5) {phi} meson transverse momentum (p{sub T}) spectra in central Au + Au collisions are found to be well described by a single exponential distribution. On the other hand, the p{sub T} spectra from p + p, d + Au and peripheral Au + Au collisions show power-law tails at intermediate and high p{sub T} and are described better by Levy distributions. The constant {phi}/K{sup -} yield ratio vs beam species, collision centrality and colliding energy is in contradiction with expectations from models having kaon coalescence as the dominant mechanism for {phi} production at RHIC. The {Omega}/{phi} yield ratio as a function of p{sub T} is consistent with a model based on the recombination of thermal s quarks up to p{sub T} {approx} 4 GeV/c, but disagrees at higher transverse momenta. The measured nuclear modification factor, R{sub dAu}, for the {phi} meson increases above unity at intermediate p{sub T}, similar to that for pions and protons, while R{sub AA} is suppressed due to the energy loss effect in central Au + Au collisions. Number of constituent quark scaling of both R{sub cp} and v{sub 2} for the {phi} meson with respect to other hadrons in Au + Au collisions at {radical}s{sub NN} = 200 GeV at intermediate p{sub T} is observed. These observations support quark coalescence as being the dominant mechanism of hadronization in the intermediate p{sub T} region at RHIC.

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

    E-Print Network [OSTI]

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

    2009-03-12T23:59:59.000Z

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

  3. Intercombination and forbidden transition rates in C-and N-like ions ,,O2 measured at a heavy-ion storage ring

    E-Print Network [OSTI]

    Chantler, Christopher T.

    ¿ ... measured at a heavy-ion storage ring E. Tra¨bert,1, * A. G. Calamai,2 J. D. Gillaspy,3 G. Gwinner,4 X-dipole forbidden transitions between the levels of the ground complex in C-like ions of O and F and in N-like ions of S have been measured optically at a heavy-ion storage ring. The lifetime results, 1.250 13 ms for the 2s2

  4. Heating of Heavy Ions by Interplanetary Coronal Mass Ejection (ICME) Driven Collisionless Shocks

    E-Print Network [OSTI]

    K. E. Korreck; T. H. Zurbuchen; S. T. Lepri; J. M . Raines

    2006-12-28T23:59:59.000Z

    Shock heating and particle acceleration processes are some of the most fundamental physical phenomena of plasma physics with countless applications in laboratory physics, space physics, and astrophysics. This study is motivated by previous observations of non-thermal heating of heavy ions in astrophysical shocks (Korreck et al. 2004). Here, we focus on shocks driven by Interplanetary Coronal Mass Ejections (ICMEs) which heat the solar wind and accelerate particles. This study focuses specifically on the heating of heavy ions caused by these shocks. Previous studies have focused only on the two dynamically dominant species, H+ and He2+ . This study utilizes thermal properties measured by the Solar Wind Ion Composition Spectrometer (SWICS) aboard the Advanced Composition Explorer (ACE) spacecraft to examine heavy ion heating. This instrument provides data for many heavy ions not previously available for detailed study, such as Oxygen (O6+, O7+), Carbon (C5+, C6+), and Iron (Fe10+). The ion heating is found to depend critically on the upstream plasma

  5. Heavy flavours in heavy-ion collisions: quenching, flow and correlations

    E-Print Network [OSTI]

    A. Beraudo; A. De Pace; M. Monteno; M. Nardi; F. Prino

    2014-12-17T23:59:59.000Z

    We present results for the quenching, elliptic flow and azimuthal correlations of heavy flavour particles in high-energy nucleus-nucleus collisions obtained through the POWLANG transport setup, developed in the past to study the propagation of heavy quarks in the Quark-Gluon Plasma and here extended to include a modeling of their hadronization in the presence of a medium. Hadronization is described as occurring via the fragmentation of strings with endpoints given by the heavy (anti-)quark Q(Qbar) and a thermal parton qbar(q) from the medium. The flow of the light quarks is shown to affect significantly the R_AA and v_2 of the final D mesons, leading to a better agreement with the experimental data. The approach allows also predictions for the angular correlation between heavy-flavour hadrons (or their decay electrons) and the charged particles produced in the fragmentation of the heavy-quark strings.

  6. Heavy quark production from jet conversions in a quark-gluon plasma 

    E-Print Network [OSTI]

    Liu, W.; Fries, Rainer J.

    2008-01-01T23:59:59.000Z

    /BNL Research Center, Brookhaven National Laboratory, Upton, New York 11973, USA (Received 13 May 2008; published 12 September 2008) Recently, it has been demonstrated that the chemical composition of jets in heavy ion collisions is significantly altered... observables that could be measured at the Relativistic Heavy Ion Collider (RHIC) or the Large Hadron Collider (LHC) [14]. In Ref. [12] it was found that conversions of light quarks to gluons could help solve the puzzle of very similar nuclear modification...

  7. On the accuracy of using Fokker Planck equation in heavy ion collision

    E-Print Network [OSTI]

    Dutta, Nirupam

    2015-01-01T23:59:59.000Z

    Application of Fokker-Planck equation to heavy quark transport in the evolving medium created in heavy ion collision is critically scrutinised. We realise that the approach introduces a moderate uncertainty in drag and diffusion coefficients culminating in huge ambiguity in the theoretical prediction of nuclear modification factor $R_{AA}$. Quantitative estimation of the error is presented by considering recent developments in this field.

  8. Lattice QCD and Hydro/Cascade Model of Heavy Ion Collisions

    E-Print Network [OSTI]

    Michael Cheng

    2010-05-11T23:59:59.000Z

    We report here on a recent lattice study of the QCD transition region at finite temperature and zero chemical potential using domain wall fermions (DWF). We also present a parameterization of the QCD equation of state obtained from lattice QCD that is suitable for use in hydrodynamics studies of heavy ion collisions. Finally, we show preliminary results from a multi-stage hydrodynamics/hadron cascade model of a heavy ion collision, in an attempt to understand how well the experimental data (e.g. particle spectra, elliptic flow, and HBT radii) can constrain the inputs (e.g. initial temperature, freezeout temperature, shear viscosity, equation of state) of the theoretical model.

  9. Azimuthally anisotropic emission of pions in symmetric heavy-ion collisions

    SciTech Connect (OSTI)

    Brill, D.; Ahner, W.; Baltes, P.; Barth, R.; Bormann, C.; Cieslak, M.; Debowski, M.; Grosse, E.; Henning, W.; Koczon, P.; Kohlmeyer, B.; Miskowiec, D.; Muentz, C.; Oeschler, H.; Poeppl, H.; Puehlhofer, F.; Sartorius, S.; Schicker, R.; Senger, P.; Shin, Y.; Speer, J.; Stein, J.; Stiebing, K.; Stock, R.; Stroebele, H.; Voelkel, K.; Wagner, A.; Walus, W. (Johann Wolfgang Goethe-Universitaet, D-6000 Frankfurt/Main (Germany) Gesellschaft fuer Schwerionenforschung, D-6100 Darmstadt (Germany) Technische Hochschule Darmstadt, D-6100 Darmstadt (Germany) Philipps-Universitaet, D-3550 Marburg (Germany) Jagiellonian University, PL-30-059 Krakow (Poland))

    1993-07-19T23:59:59.000Z

    Triple differential cross sections [ital d][sup 3][sigma]/[ital dp][sup 3] for charged pions produced in symmetric heavy-ion collisions were measured with the KaoS magnetic spectrometer at the heavy-ion synchrotron facility SIS at GSI. The correlations between the momentum vectors of charged pions and the reaction plane in [sup 197]Au+[sup 197]Au collisions at an incident energy of 1 GeV/nucleon were determined. We observe, for the first time, an azimuthally anisotropic distribution of pions, with enhanced emission perpendicular to the reaction plane. The anisotropy is most pronounced for pions of high transverse momentum in semicentral collisions.

  10. Dispersion relation approach to sub-barrier heavy-ion fusion reactions

    SciTech Connect (OSTI)

    Franzin, V.L.M.; Hussein, M.S.

    1988-11-01T23:59:59.000Z

    We discuss the conditions under which the dispersion relation technique, extensively employed in the context of elastic scattering, can be used in the analysis of heavy-ion fusion reactions. General unitarity defect arguments are used for this purpose. With the aid of an inverse dispersion relation, which gives the imaginary part of the fusion inclusive polarization potential in terms of the principal part integral involving the real part of the inclusive polarization potential, the sub-barrier fusion of heavy ions is discussed. The system /sup 16/O+/sup A/Sm is taken as an example.

  11. Selected Topics in the Physics of Heavy Ion Collisions (1/3)

    ScienceCinema (OSTI)

    None

    2011-04-25T23:59:59.000Z

    In these lectures, I discuss some classes of measurements accessible in heavy ion collisions at the LHC. How can these observables be measured, to what extent can they be calculated, and what do they tell us about the dense mesoscopic system created during the collision? In the first lecture, I shall focus in particular on measurements that constrain the spatio-temporal picture of the collisions and that measure centrality, orientations and extensions. In the subsequent lectures, I then discuss on how classes of measurements allow one to characterize collective phenomena, and to what extent these measurements can constrain the properties of matter produced in heavy ion collisions.

  12. The beam energy dependence of collective flow in heavy ion collisions

    E-Print Network [OSTI]

    Petersen, Hannah; Auvinen, Jussi; Bleicher, Marcus

    2015-01-01T23:59:59.000Z

    The major goals of heavy ion research are to explore the phase diagram of quantum chromodynamics (QCD) and to investigate the properties of the quark gluon plasma (QGP), a new state of matter created at high temperatures and/or densities. Collective anisotropic flow is one of the most promising observables to gain insights about the properties of the system created in relativistic heavy ion reactions. The current status of the beam energy dependence of the first three Fourier coefficients of the azimuthal distribution of the produced particles $v_1$ to $v_3$ within hybrid transport plus hydrodynamics approaches are summarized.

  13. The beam energy dependence of collective flow in heavy ion collisions

    E-Print Network [OSTI]

    Hannah Petersen; Jan Steinheimer; Jussi Auvinen; Marcus Bleicher

    2015-03-11T23:59:59.000Z

    The major goals of heavy ion research are to explore the phase diagram of quantum chromodynamics (QCD) and to investigate the properties of the quark gluon plasma (QGP), a new state of matter created at high temperatures and/or densities. Collective anisotropic flow is one of the most promising observables to gain insights about the properties of the system created in relativistic heavy ion reactions. The current status of the beam energy dependence of the first three Fourier coefficients of the azimuthal distribution of the produced particles $v_1$ to $v_3$ within hybrid transport plus hydrodynamics approaches are summarized.

  14. Constancy of energy partition in central heavy-ion reactions at intermediate energies

    E-Print Network [OSTI]

    Z. Basrak; Ph. Eudes; M. Zori?; F. Sébille

    2012-09-10T23:59:59.000Z

    Semiclassical transport simulation of nucleus-nucleus collisions for the range of incident energy from about the Fermi energy up to a few hundred MeV per nucleon evidences that the maximal excitation energy put into a nuclear system during the early compact stage of heavy-ion reaction is a constant fraction of the center-of-mass available energy of the system. Analysis of experimental data without presuming reaction mechanism dominating the collision process on the best corroborate the found constancy of energy partition in central heavy-ion reactions.

  15. Evaluation of excitation energy and spin from light charged particles multiplicities in heavy-ion collisions

    E-Print Network [OSTI]

    Steckmeyer, J C; Grotowski, K; Pawowski, P; Aiello, S; Anzalone, A; Bini, M; Borderie, B; Bougault, R; Cardella, G; Casini, G; Cavallaro, S; Charvet, J L; Dayras, R; De Filippo, E; Durand, D; Femin, S; Frankland, J D; Galíchet, E; Geraci, M; Giustolisi, F; Guazzoni, P; Iacono-Manno, M; Lanzalone, G; Lanzan, G; Le Neindre, N; Lo Nigro, S; Lo Piano, F; Olmi, A; Pagano, A; Papa, M; Pârlog, M; Pasquali, G; Piantelli, S; Pirrone, S; Politi, G; Porto, F; Rivet, M F; Rizzo, F; Rosato, E; Roy, R; Sambataro, S; Sperduto, M L; Stefanini, A A; Sutera, C; Tamain, B; Vient, E; Volant, C; Wieleczko, J P; Zetta, L

    2005-01-01T23:59:59.000Z

    A simple procedure for evaluating the excitation energy and the spin transfer in heavy-ion dissipative collisions is proposed. It is based on a prediction of the GEMINI evaporation code : for a nucleus with a given excitation energy, the average number of emitted protons decreases with increasing spin, whereas the average number of alpha particles increases. Using that procedure for the reaction 107Ag+58Ni at 52 MeV/nucleon, the excitation energy and spin of quasi-projectiles have been evaluated. The results obtained in this way have been compared with the predictions of a model describing the primary dynamic stage of heavy-ion collisions.

  16. Studies of Limits on Uncontrolled Heavy Ion Beam Losses for Allowing Hands-On Maintenance

    SciTech Connect (OSTI)

    Reginald M. Ronningen; Igor Remec

    2010-09-11T23:59:59.000Z

    Dose rates from accelerator components activated by 1 W/m beam losses are obtained semiempirically for a 1 GeV proton beam and by use of Monte Carlo transport codes for the proton beam and for 777 MeV/u 3He, 500 MeV/u 48Ca, 86Kr, 136Xe, and 400 MeV/u 238U ions. The dose rate obtained by the semi-empirical method, 0.99 mSv/h (99 mrem/h) at 30 cm, 4 h after 100 d irradiation by a 1-GeV proton beam, is consistent with studies at several accelerator facilities and with adopted hands-on maintenance dose rate limits. Monte Carlo simulations verify this result for protons and extend studies to heavy ion beam losses in drift-tube linac and superconducting linac accelerating structures. The studies indicate that the 1 W/m limit imposed on uncontrolled beam losses for high-energy proton beams might be relaxed for heavy ion beams. These studies further suggest that using the ratio of neutrons produced by a heavy ion beam to neutrons produced by a proton beam along with the dose rate from the proton beam (for thin-target scenarios) should allow an estimate of the dose rates expected from heavy ion beam losses.

  17. Multiphase transport model for relativistic heavy ion collisions

    E-Print Network [OSTI]

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

    2005-01-01T23:59:59.000Z

    ] by requiring events to each have at least one charged particle in both ends of the pseudorapidity intervals 3 CERN ISR data is different. From the comparison with the AMPT inelastic results (solid curves...+Au collisions thus provide the opportunity to study the properties of this so-called quark-gluon plasma (QGP). At the future Large Hadron Collider (LHC) at CERN, which will allow Pb+Pb collisions at ? sNN = 5.5 TeV, the produced quark-gluon plasma...

  18. More than mass proportional heating of heavy ions by supercritical collisionless shocks in the solar corona

    E-Print Network [OSTI]

    Zimbardo, Gaetano

    2009-01-01T23:59:59.000Z

    We propose a new model for explaining the observations of more than mass proportional heating of heavy ions in the polar solar corona. We point out that a large number of small scale intermittent shock waves can be present in the solar corona. The energization mechanism is, essentially, the ion reflection off supercritical quasi-perpendicular collisionless shocks in the corona and the subsequent acceleration by the motional electric field ${\\bf E} = - (1/c) {\\bf V} \\times {\\bf B}$. The acceleration due to ${\\bf E}$ is perpendicular to the magnetic field, in agreement with observations, and is more than mass proportional with respect to protons, because the heavy ion orbit is mostly upstream of the quasi-perpendicular shock foot. The observed temperature ratios between O$^{5+}$ ions and protons in the polar corona, and between $\\alpha$ particles and protons in the solar wind are easily recovered.

  19. Estimation of Heavy Ion Densities From Linearly Polarized EMIC Waves At Earth

    SciTech Connect (OSTI)

    Kim, Eun-Hwa; Johnson, Jay R.; Lee, Dong-Hun

    2014-02-24T23:59:59.000Z

    Linearly polarized EMIC waves are expected to concentrate at the location where their wave frequency satisfies the ion-ion hybrid (IIH) resonance condition as the result of a mode conversion process. In this letter, we evaluate absorption coefficients at the IIH resonance in the Earth geosynchronous orbit for variable concentrations of helium and azimuthal and field-aligned wave numbers in dipole magnetic field. Although wave absorption occurs for a wide range of heavy ion concentration, it only occurs for a limited range of azimuthal and field-aligned wave numbers such that the IIH resonance frequency is close to, but not exactly the same as the crossover frequency. Our results suggest that, at L = 6.6, linearly polarized EMIC waves can be generated via mode conversion from the compressional waves near the crossover frequency. Consequently, the heavy ion concentration ratio can be estimated from observations of externally generated EMIC waves that have polarization.

  20. Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a,

    E-Print Network [OSTI]

    Solar-wind protons and heavy ions sputtering of lunar surface materials A.F. Barghouty a, , F Available online 21 December 2010 Keywords: Solar wind sputtering Lunar regolith KREEP soil Potential a c t Lunar surface materials are exposed to $1 keV/amu solar-wind protons and heavy ions on almost

  1. Cascade Problems in Some Atomic Lifetime Measurements at a Heavy-Ion Storage Ring

    SciTech Connect (OSTI)

    Trabert, E; Hoffmann, J; Krantz, C; Wolf, A; Ishikawa, Y; Santana, J

    2008-10-09T23:59:59.000Z

    Lifetimes of 3s{sup 2}3p{sup k} ground configuration levels of Al-, Si-, P-, and S-like ions of Be, Co, and Ni have been measured at a heavy-ion storage ring. Some of the observed decay curves show strong evidence of cascade repopulation from specific 3d levels that feature lifetimes in the same multi-millisecond range as the levels of the ground configuration.

  2. On the possibility of spontaneous generation of turbulent Alfvén waves in solar plasma by heavy ions

    SciTech Connect (OSTI)

    Wu, C. S. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China) [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China); Institute of Space Science, National Central University, Zhongli, Taiwan (China); Zhao, G. Q. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China) [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China); University of Chinese Academy of Sciences, Beijing (China); Chen, L.; Wu, D. J. [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China)] [Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing (China)

    2013-08-15T23:59:59.000Z

    In this paper, we discuss spontaneous generation of Alfvén waves. The discussion is motivated by the study of the solar transition region. We show that the heavy ions in this region can play critical roles. A quasilinear theory is derived. On the basis of this theory, we can discuss the saturation level of the wave spectral energy associated with each species of ions. Several essential issues relevant to the transition region are also discussed.

  3. HEAVY-ION-INDUCED TERNARY FISSION AS A PROBE OF THE DYNAMICAL DECAY OF

    E-Print Network [OSTI]

    de Souza, Romualdo T.

    of Nuclear Fission Dynamics . . . . . . . . . . . . . . . . . . 5 1.2.1 Total Kinetic Energy of the Fission of Ternary Fission . . . . . . . . . . . . . . 11 1.4 Models of Nuclear FissionHEAVY-ION-INDUCED TERNARY FISSION AS A PROBE OF THE DYNAMICAL DECAY OF EXCITED NUCLEI Todd A

  4. Biological and medical research with accelerated heavy ions at the Bevalac, 1977-1980. [Lead abstract

    SciTech Connect (OSTI)

    Pirruccello, M.C.; Tobias, C.A. (eds.)

    1980-11-01T23:59:59.000Z

    Separate abstracts were prepared for the 46 papers presented in this progress report. This report is a major review of studies with accelerated heavy ions carried out by the Biology and Medicine Division of Lawrence Berkeley Laboratory from 1977 to 1980. (KRM)

  5. Fermionic Molecular Dynamics: Multifragmentation in heavy-ion collisions and in excited nuclei

    E-Print Network [OSTI]

    H. Feldmeier; J. Schnack

    1997-03-17T23:59:59.000Z

    Within Fermionic Molecular Dynamics we investigate fragmentation of a compound system which was created in a heavy-ion collision at a beam energy in the Fermi energy domain and the decay of excited iron nuclei. We show that in FMD many-body correlations play an important role in the formation of fragments.

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

    E-Print Network [OSTI]

    Scott Pratt; Silvio Petriconi

    2003-06-16T23:59:59.000Z

    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.

  7. Jet Quenching in Heavy Ion Collisions from AdS/CFT

    E-Print Network [OSTI]

    Jose D. Edelstein; Carlos A. Salgado

    2008-05-29T23:59:59.000Z

    The phenomenon of jet supression observed in highly energetic heavy ion collisions is discussed. The focus is devoted to the stunning applications of the AdS/CFT correspondence to describe these real time processes, hard to be illuminated by other means. In particular, the introduction of as many flavors as colors into the quark-gluon plasma is scrutinized.

  8. Probing anharmonic properties of nuclear surface vibration by heavy-ion fusion reactions

    E-Print Network [OSTI]

    N. Takigawa; K. Hagino; S. Kuyucak

    1997-06-28T23:59:59.000Z

    Describing fusion reactions between ^{16}O and ^{154}Dy and, between ^{16}O and ^{144}Sm by the $sd-$ and $sdf-$ interacting boson model, we show that heavy-ion fusion reactions are strongly affected by anharmonic properties of nuclear surface vibrations and nuclear shape, and thus provide a powerful method to study details of nuclear structure and dynamics.

  9. argonne superconducting heavy-ion: Topics by E-print Network

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

    argonne superconducting heavy-ion First Page Previous Page 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 Next Page Last Page Topic Index 1 A LARGE...

  10. Kinetic And Potential Sputtering Of Lunar Regolith: The Contribution Of The Heavy (Minority) Solar Wind Ions

    E-Print Network [OSTI]

    Kinetic And Potential Sputtering Of Lunar Regolith: The Contribution Of The Heavy (Minority) Solar Wind Ions F.W. Meyera1 , P.R. Harrisa2 , H.M. Meyer IIIb , H. Hijazia , A.F. Barghoutyc a Physics, Huntsville, AL 35812, USA Abstract. In this paper the sputtering of lunar regolith by protons and solar wind

  11. {gamma} spectroscopy around doubly magic {sup 48}Ca by heavy-ion transfer reactions

    SciTech Connect (OSTI)

    Leoni, Silvia [Department of Physics, University of Milano and INFN, Milano (Italy)

    2012-10-20T23:59:59.000Z

    {gamma} spectroscopy of neutron-rich nuclei around {sup 48}Ca is performed by the heavy-ion transfer reaction {sup 48}Ca on {sup 64}Ni at 282 MeV, with the PRISMA-CLARA setup at Legnaro Laboratory. Angular distributions, polarizations and lifetimes analysis probe spin and parities of several excited states, shading lights on their configuration. In the one neutron transfer channels, {sup 49}Ca and {sup 47}Ca, states arising by coupling a single particle to the 3{sup -} phonon of {sup 48}Ca are observed, showing the robustness of nuclear collectivity in rather light systems. The work demonstrates the feasibility of complete in-beam {gamma}-spectroscopy with heavy-ion transfer reactions and provides a method that can be further exploited in the future with heavy targets and radioactive beams.

  12. Indications of Conical Emission of Charged Hadrons at the BNL Relativistic HeavyIon Collider

    SciTech Connect (OSTI)

    STAR Coll

    2009-02-09T23:59:59.000Z

    Three-particle azimuthal correlation measurements with a high transverse momentum trigger particle are reported for pp, d + Au, and Au + Au collisions at {radical}s{sub NN} = 200 GeV by the STAR experiment. Dijet structures are observed in pp, d + Au and peripheral Au + Au collisions. An additional structure is observed in central Au + Au data, signaling conical emission of correlated charged hadrons. The conical emission angle is found to be {theta} = 1.37 {+-} 0.02(stat){sub -0.07}{sup +0.06}(syst), independent of p{sub {perpendicular}}.

  13. Comparison of accelerator codes for a RHIC (Relativistic Heavy Ion Collider) lattice

    SciTech Connect (OSTI)

    Milutinovic, J.; Ruggiero, A.G.

    1989-01-01T23:59:59.000Z

    We present the results of comparison of performances of several tracking or/and analysis codes. The basic purpose of this program was to assess reliability and accuracy of these codes, i.e., to determine the so-called ''error bars'' for the predicted values of tunes and other lattice functions as a minimum and, if possible, to discover potential difficulties with underlying physical models in these codes, inadequate algorithms, residual bugs and the like. Not only have we been able to determine the error bars, which for instance for the tunes at dp/p = +1% are ..delta nu../sub xi/ = 0.0027, ..delta nu../sub y/ = 0.0010, but also our program has brought about improvements of several codes. 8 refs., 3 figs., 2 tabs.

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

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiation Protection Technical s o Freiberg andReindustrializationLivermoreRelativistic

  15. Measuring Radiation Damage from Heavy Energetic Ions in Aluminum

    SciTech Connect (OSTI)

    Kostin, M., PI-MSU; Ronningen, R., PI-MSU; Ahle, L., PI-LLNL; Gabriel, T., Scientific Investigation and Development; Mansur, L., PI-ORNL; Leonard, K., ORNL; Mokhov, N., FNAL; Niita, K., RIST, Japan

    2009-02-21T23:59:59.000Z

    An intense beam of 122 MeV/u (9.3 GeV) 76Ge ions was stopped in aluminum samples at the Coupled Cyclotron Facility at NSCL, MSU. Attempts were made at ORNL to measure changes in material properties by measuring changes in electrical resistivity and microhardness, and by transmission electron microscopy characterization, for defect density caused by radiation damage, as a function of depth and integrated ion flux. These measurements are relevant for estimating damage to components at a rare isotope beam facility.

  16. Overview of Theory and Modeling in the Heavy Ion Fusion Virtual National Laboratory

    E-Print Network [OSTI]

    Davidson, R C; Celata, C M; Cohen, R H; De Hoon, M; Friedman, A; Grote, D P; Henestroza, E; Kaganovich, I D; Lee, E P; Lee, W W; Lund, S M; Olson, C L; Qin, H; Rose, D V; Sharp, W M; Startsev, E A; Tzenov, Stephan I; Vay, J L; Welch, D R; Yu, S S

    2003-01-01T23:59:59.000Z

    This paper presents analytical and simulation studies of intense heavy ion beam propagation, including the injection, acceleration, transport and compression phases, and beam transport and focusing in background plasma in the target chamber. Analytical theory and simulations that support the High Current Experiment (HCX), the Neutralized Transport Experiment (NTX), and the advanced injector development program are being used to provide a basic understanding of the nonlinear beam dynamics and collective processes, and to develop design concepts for the next-step Integrated Beam Experiment (IBX), an Integrated Research Experiment (IRE), and a heavy ion fusion driver. Three-dimensional (3-D) nonlinear perturbative simulations have been applied to collective instabilities driven by beam temperature anisotropy and to two-stream interactions between the beam ions and any unwanted background electrons. Three-dimensional particle-in-cell simulations of the 2 MV Electrostatic Quadrupole (ESQ) injector have clarified t...

  17. Semiempirical range and stopping power values for heavy ions

    E-Print Network [OSTI]

    Schilling, Ralph Franklin, III

    1968-01-01T23:59:59.000Z

    S ", '". IE: PIRICAL RAiiTGE ARE STOPPIZG PO'(/ER VALUES POR HEAVY IOUS A Thesis by RALPH PRKVKLIM SCHILLING III Subm' tted to the Graduate College of the Texas A8:)~I University in Partial fulfillmert of the requirements for the degree of I... from the tcchn'qu-s used 1n p"blication has, for the most part, limited their usefulness 1n determining specific values. i&1th this in mind. , the results obtained in this pro?'ect arc er;pressed in tabular form rather than 1n graphical form. A...

  18. The Heavy Ion Fusion Science Virtual National Laboratory

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What'sis Taking Over Our InstagramStructureProposedPAGESafetyTed5,AuditThe FiveBiofuelsGEThe The Heavy

  19. Sandia National Labs: PCNSC: Heavy Ion Backscattering Spectrometry

    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: Alternative1 First Use of Energy for All Purposes (Fuel and Nonfuel), 2002; Level:Energy: Grid Integration Redefining What's PossibleRadiationImplementingnpitche HomeCybernetics:TableTableTableTableTableHome About UsHeavy

  20. Heavy-ion transfer reactions at large internuclear distance

    SciTech Connect (OSTI)

    Montanari, D.; Corradi, L.; Szilner, S.; Pollarolo, G.; Fioretto, E.; Stefanini, A. M.; Farnea, E.; Michelagnoli, C.; Montagnoli, G.; Scarlassara, F.; Ur, C. A.; Courtin, S.; Goasduff, A.; Haas, F.; Mijatovic, T.; Soic, N.; Grebosz, J. [Dipartimento di Fisica e Astronomia, Universita di Padova, I-35131, Padova (Italy) and Istituto Nazionale di Fisica Nucleare, I-35131, Padova (Italy); Istituto Nazionale di Fisica Nucleare, Laboratori Nazionali di Legnaro, I-35020 Legnaro (Italy)

    2012-10-20T23:59:59.000Z

    The transfer reaction for the {sup 116}Sn+{sup 60}Ni system has been studied using the PRISMA magnetic spectrometer at different bombarding energies from above to well below the Coulomb barrier. The experiment has been done in inverse kinematics and light target-like ions have been detected with PRISMA placed at very forward angles. Good mass, nuclear charge and kinetic energy resolutions have been achieved. Sufficient statistics has been accumulated to extract angular distributions for different bombarding energies have been extracted and the response function of the spectrometer has been studied to correct for the aberration due to the transport of the ions in PRISMA. The comparison between the present case and the previously measured {sup 96}Zr+{sup 40}Ca system, superfluid and near closed shells nuclei, respectively, should significantly improve our understanding of nucleon-nucleon correlation properties in multinucleon transfer processes.

  1. Source dimensions in ultrarelativistic heavy-ion collisions

    SciTech Connect (OSTI)

    Herrmann, M.; Bertsch, G.F. (Institute for Nuclear Theory, HN-12, University of Washington, Seattle, Washington 98195 (United States) Physics Department, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1995-01-01T23:59:59.000Z

    Recent experiments on pion correlations, interpreted as interferometric measurements of the collision zone, are compared with models that distinguish a prehadronic phase and a hadronic phase. The models include prehadronic longitudinal expansion, conversion to hadrons in local kinetic equilibrium, and rescattering of the produced hadrons. We find that the longitudinal and outward radii are surprisingly sensitive to the algorithm used for two-body collisions. The longitudinal radius measured in collisions of 200 GeV/nucleon sulfur nuclei on a heavy target requires the existence of a prehadronic phase which converts to the hadronic phase at densities around 0.8--1.0 GeV/fm[sup 3]. The transverse radii cannot be reproduced without introducing more complex dynamics into the transverse expansion.

  2. Systematics of heavy-ion fusion hindrance at extreme sub-barrier energies

    E-Print Network [OSTI]

    C. L. Jiang; B. B. Back; H. Esbensen; R. V. F. Janssens; abd K. E. Rehm

    2005-08-01T23:59:59.000Z

    The recent discovery of hindrance in heavy-ion induced fusion reactions at extreme sub-barrier energies represents a challenge for theoretical models. Previously, it has been shown that in medium-heavy systems, the onset of fusion hindrance depends strongly on the "stiffness" of the nuclei in the entrance channel. In this work, we explore its dependence on the total mass and the $Q$-value of the fusing systems and find that the fusion hindrance depends in a systematic way on the entrance channel properties over a wide range of systems.

  3. 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

    2014-10-01T23:59:59.000Z

    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.

  4. Systematics of heavy-ion fusion hindrance at extreme sub-barrier energies.

    SciTech Connect (OSTI)

    Jiang, C. L.; Back, B. B.; Esbensen, H.; Janssens, R. V. F.; Rehm, K. E.; Physics

    2006-01-01T23:59:59.000Z

    The recent discovery of hindrance in heavy-ion induced fusion reactions at extreme sub-barrier energies represents a challenge for theoretical models. Previously, it has been shown that in medium-heavy systems, the onset of fusion hindrance depends strongly on the 'stiffness' of the nuclei in the entrance channel. In this work, we explore its dependence on the total mass and the Q-value of the fusing systems and find that the fusion hindrance depends in a systematic way on the entrance channel properties over a wide range of systems.

  5. Systematics of heavy-ion fusion hindrance at extreme sub-barrier energies

    SciTech Connect (OSTI)

    Jiang, C.L.; Back, B.B.; Esbensen, H.; Janssens, R.V.F.; Rehm, K.E. [Physics Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2006-01-15T23:59:59.000Z

    The recent discovery of hindrance in heavy-ion induced fusion reactions at extreme sub-barrier energies represents a challenge for theoretical models. Previously, it has been shown that in medium-heavy systems, the onset of fusion hindrance depends strongly on the ''stiffness'' of the nuclei in the entrance channel. In this work, we explore its dependence on the total mass and the Q-value of the fusing systems and find that the fusion hindrance depends in a systematic way on the entrance channel properties over a wide range of systems.

  6. Isospin relaxation time in heavy-ion collisions at intermediate energies

    E-Print Network [OSTI]

    Li, Ba; Ko, Che Ming.

    1998-01-01T23:59:59.000Z

    n e intermediat . I PHYSICAL REVIEW C APRIL 1998VOLUME 57, NUMBER 4 by deep-inelastic heavy-ion collisions at low energies, where the isospin degree of freedom has been found to first reach equilibrium @11?13#. Recent experimental studies... note that this definition is somewhat different from that one would usually use, i.e., l(t )51/e . 2065 ? 1998 The American Physical Society Another important property of the heavy residue is pos- sible existence of dynamical instability. To study...

  7. Electron loss from fast heavy ions: Target-scaling dependence

    SciTech Connect (OSTI)

    DuBois, R. D. [Department of Physics, Missouri University of Science and Technology, Rolla, Missouri 65409 (United States); Santos, A. C. F.; Montenegro, E. C. [Instituto de Fisica, UFRJ, Caixa Postal 68528 Rio de Janeiro, BR-21941-972 RJ (Brazil); Sigaud, G. M. [Departamento de Fisica, Pontificia Universidade Catolica do Rio de Janeiro, Caixa Postal 38071, Rio de Janeiro, BR-22452-970 RJ (Brazil)

    2011-08-15T23:59:59.000Z

    The target dependence for projectile electron loss is investigated using experimental data taken from the literature. Impact energies range from a few tens of eV/u to tens of MeV/u. For energies less than several MeV/u, the target dependences are shown to be very similar, independent of projectile species and charge state. Overall, however, with increasing impact energy the cross-section dependence on the target nuclear charge systematically increases. It is shown that none of the existing cross-section target scaling models reproduce these features. A model, based on Born scaling and including both the antiscreening and screening contributions to projectile electron loss, is developed. With the inclusion of relativistic effects, which increase the contribution from both channels at high energies, and ''target saturation'' effects, which reduce the contribution from the screening term for heavy targets and lower impact energies, this model describes quite reasonably all available experimental data. A simple scaling formula that reproduces the measured atomic number and impact velocity dependences is provided. This formula is applicable for projectile electron loss in collisions with either atomic or molecular targets and for impact energies ranging from a few to tens of MeV/u.

  8. Soft vs Hard: Particle Production in High-Energy Heavy-Ion Collisions

    E-Print Network [OSTI]

    Mishra, Aditya Nath; Pareek, Pooja; Behera, Nirbhay K; Sahoo, Raghunath; Nandi, Basanta K

    2015-01-01T23:59:59.000Z

    The centrality dependence of pseudorapidity density of charged particles and transverse energy is studied for a wide range of collision energies for heavy-ion collisions at midrapidity. A two-component model approach has been adopted to quantify the soft and hard components of particle production, coming from nucleon participants and binary nucleon-nucleon collisions, respectively. Within experimental uncertainties, the hard component contributing to the particle production has been found to be nearly independent of collisions energy from RHIC to LHC. The suppression of high-$p_{\\rm T}$ hadrons and jets in the medium created in heavy-ion collisions seem to play a role in the nearly independent collision energy behavior of hard components in particle production. We also use MC event generators, like HIJING and AMPT to study the possible effects of the suppression of high $p_{T}$ partons inside the medium and the effect of the threshold momentum for minijets, contributing to hard scattering processes.

  9. Effect of equilibrium phase transition on multiphase transport in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Yu Meiling; Du Jiaxin; Liu Lianshou

    2006-06-24T23:59:59.000Z

    The hadronization scheme for parton transport in relativistic heavy ion collisions is considered in detail. It is pointed out that the traditional scheme for particles being freezed out one by one leads to serious problem on unreasonable long lifetime for partons. A super-cooling of the parton system followed by a collective phase transition is implemented in a simple way. It turns out that the modified model with a global phase transition is able to reproduce the experimental longitudinal distributions of final state particles better than the original one does. The encouraging results indicate that a relevant parton transport model for relativistic heavy ion collision should take equilibrium phase transition into proper account.

  10. Net-charge probability distributions in heavy ion collisions at chemical freeze-out

    E-Print Network [OSTI]

    P. Braun-Munzinger; B. Friman; F. Karsch; K. Redlich; V. Skokov

    2011-11-21T23:59:59.000Z

    We explore net charge probability distributions in heavy ion collisions within the hadron resonance gas model. The distributions for strangeness, electric charge and baryon number are derived. We show that, within this model, net charge probability distributions and the resulting fluctuations can be computed directly from the measured yields of charged and multi-charged hadrons. The influence of multi-charged particles and quantum statistics on the shape of the distribution is examined. We discuss the properties of the net proton distribution along the chemical freeze-out line. The model results presented here can be compared with data at RHIC energies and at the LHC to possibly search for the relation between chemical freeze-out and QCD cross-over lines in heavy ion collisions.

  11. Noncommutativity and Lorentz Violation in Relativistic Heavy Ion Collisions at LHC

    SciTech Connect (OSTI)

    Castorina, P. [Dipartimento di Fisica, Universita di Catania, Via Santa Sofia 64, I-95123 Catania (Italy); INFN, Sezione di Catania, I-95123 Catania (Italy); Iorio, A. [Faculty of Mathematics and Physics, Charles University in Prague V Holesovickach 2, CZ-18000 Prague 8 (Czech Republic); Zappala, D. [INFN, Sezione di Catania, I-95123 Catania (Italy)

    2010-12-22T23:59:59.000Z

    One shows that relativistic heavy ion collisions could be used as an experimental probe to detect fundamental properties of spacetime long speculated about. The results rely on the recent proposal that magnetic fields of intensity much larger than that of magnetars should be produced at the beginning of the collisions and this could have an important impact on the experimental manifestation of a noncommutative spacetime. Indeed, in the noncommutative generalization of electrodynamics the interplay between a nonzero noncommutative parameter and an external magnetic field leads us to predict the production of lepton pairs of low invariant mass by free photons(an event forbidden by Lorentz invariant electrodynamics) in relativistic heavy ion collisions at present and future available energies. This unique channel can be clearly considered as a signature of noncommutativity.

  12. Turbulent thermalization process in high-energy heavy-ion collisions

    E-Print Network [OSTI]

    Jürgen Berges; Björn Schenke; Sören Schlichting; Raju Venugopalan

    2014-09-05T23:59:59.000Z

    We discuss the onset of the thermalization process in high-energy heavy-ion collisions from a weak coupling perspective, using classical-statistical real-time lattice simulations as a first principles tool to study the pre-equilibrium dynamics. Most remarkably, we find that the thermalization process is governed by a universal attractor, where the space-time evolution of the plasma becomes independent of the initial conditions and exhibits the self-similar dynamics characteristic of wave turbulence. We discuss the consequences of our weak coupling results for the thermalization process in heavy-ion experiments and briefly comment on the use of weak coupling techniques at larger values of the coupling.

  13. Transport theory of relativistic heavy-ion collisions with chiral symmetry

    SciTech Connect (OSTI)

    Zhang, W.; Wilets, L. (Department of Physics, FM-15, University of Washington, Seattle, Washington 98195 (United States))

    1992-04-01T23:59:59.000Z

    A transport theory with chiral symmetry is developed from the quark level to describe the chiral dynamics in high-energy heavy-ion collisions. The strong interaction is treated effectively by the Nambu--Jona-Lasinio model. A set of generalized Boltzmann equations of constitutent quarks and mesons is derived by using the closed time-path Green's function technique and a loop expansion approach. Chiral symmetry, energy spectrum and dissipation, and density distributions of constitutent quarks and mesons can then be studied self-consistently in the nonequilibrium dynamical processes. In particular, the discussion for exploring chiral symmetry breaking and its restoration and for studying dynamics of meson production (as collective {ital q{bar q}} excitations) in heavy-ion collisions is presented.

  14. A Harmonic Kicker Scheme for the Circulator Cooler Ring in the Proposed Medium Energy Electron-Ion Collider

    SciTech Connect (OSTI)

    Nissen, Edward W.; Hutton, Andrew M.; Kimber, Andrew J.

    2013-06-01T23:59:59.000Z

    The current electron cooler design for the proposed Medium Energy Electron-Ion collider (MEIC) at Jefferson Lab utilizes a circulator ring for reuse of the cooling electron bunch up to 100 times to cool the ion beams. This cooler requires a fast kicker system for injecting and extracting individual bunches in the circulator ring. Such a kicker must work at a high repetition rate, up to 7.5 to 75 MHz depending on the number of turns in the recirculator ring. It also must have a very short rise and fall time (of order of 1 ns) such that it will kick an individual bunch without disturbing the others in the ring. Both requirements are orders of magnitude beyond the present state-of-the-art as well as the goals of other on-going kicker R&D programs such as that for the ILC damping rings. In this paper we report a scheme of creating this fast, high repetition rate kicker by combining RF waveforms at multiple frequencies to create a kicker waveform that will, for example, kick every eleventh bunch while leaving the other ten unperturbed. We also present a possible implementation of this scheme as well as discuss its limitations.

  15. Sound Wave in Hot Dense Matter Created in Heavy Ion Collision

    E-Print Network [OSTI]

    X. Sun; Z. Yang

    2005-12-14T23:59:59.000Z

    A model to study the sound wave in hot dense matter created in heavy ion collisions by jet is proposed.The preliminary data of jet shape analysis of PHENIX Collaboration for all centralities and two directions is well explained in this model. Then the wavelength of the sound wave, the natural frequency of the hot dense matter and the speed of sound wave are estimated from the fit.

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

    E-Print Network [OSTI]

    Wojciech Florkowski; Wojciech Broniowski

    2004-10-19T23:59:59.000Z

    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.

  17. Actinide Production in the Reaction of Heavy Ions withCurium-248

    SciTech Connect (OSTI)

    Moody, K.J.

    1983-07-01T23:59:59.000Z

    Chemical experiments were performed to examine the usefulness of heavy ion transfer reactions in producing new, neutron-rich actinide nuclides. A general quasi-elastic to deep-inelastic mechanism is proposed, and the utility of this method as opposed to other methods (e.g. complete fusion) is discussed. The relative merits of various techniques of actinide target synthesis are discussed. A description is given of a target system designed to remove the large amounts of heat generated by the passage of a heavy ion beam through matter, thereby maximizing the beam intensity which can be safely used in an experiment. Also described is a general separation scheme for the actinide elements from protactinium (Z = 91) to mendelevium (Z = 101), and fast specific procedures for plutonium, americium and berkelium. The cross sections for the production of several nuclides from the bombardment of {sup 248}Cm with {sup 18}O, {sup 86}Kr and {sup 136}Xe projectiles at several energies near and below the Coulomb barrier were determined. The results are compared with yields from {sup 48}Ca and {sup 238}U bombardments of {sup 248}Cm. Simple extrapolation of the product yields into unknown regions of charge and mass indicates that the use of heavy ion transfer reactions to produce new, neutron-rich above-target species is limited. The substantial production of neutron-rich below-target species, however, indicates that with very heavy ions like {sup 136}Xe and {sup 238}U the new species {sup 248}Am, {sup 249}Am and {sup 247}Pu should be produced with large cross sections from a {sup 248}Cm target. A preliminary, unsuccessful attempt to isolate {sup 247}Pu is outlined. The failure is probably due to the half life of the decay, which is calculated to be less than 3 minutes. The absolute gamma ray intensities from {sup 251}Bk decay, necessary for calculating the {sup 251}Bk cross section, are also determined.

  18. Work distribution of an expanding gas and transverse energy production in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Zhang, Bin

    2013-01-01T23:59:59.000Z

    The work distribution of an expanding extreme relativistic gas is shown to be a gamma distribution with a different shape parameter as compared with its non-relativistic counterpart. This implies that the shape of the transverse energy distribution in relativistic heavy ion collisions depends on the particle contents during the evolution of the hot and dense matter. Therefore, transverse energy fluctuations provide additional insights into the Quark-Gluon Plasma produced in these collisions.

  19. Work distribution of an expanding gas and transverse energy production in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Bin Zhang; Jay P. Mayfield

    2014-01-19T23:59:59.000Z

    The work distribution of an expanding extreme relativistic gas is shown to be a gamma distribution with a different shape parameter as compared with its non-relativistic counterpart. This implies that the shape of the transverse energy distribution in relativistic heavy ion collisions depends on the particle contents during the evolution of the hot and dense matter. Therefore, transverse energy fluctuations provide additional insights into the Quark-Gluon Plasma produced in these collisions.

  20. Jet reconstruction in heavy ion collisions (emphasis on Underlying Event background subtraction)

    E-Print Network [OSTI]

    M. Estienne

    2009-10-13T23:59:59.000Z

    A modification of the internal structure of jets is expected due to the production of a dense QCD medium, the Quark Gluon Plasma, in heavy-ion collisions. We discuss some aspects of jet reconstruction in p+p and A+A collisions and emphasize the dramatically increased contribution of the underlying event in nucleus-nucleus collisions as compared with the vacuum case. We conclude with its consequences on the full jet spectrum and fragmentation function extraction at LHC.

  1. $?$ vacua states in heavy ion collisions in presence of dissipation and noise

    E-Print Network [OSTI]

    A. K. Chaudhuri

    2001-09-24T23:59:59.000Z

    We have studied possible formation of $\\Theta$ vacua states in heavy ion collisions. Random phases of the chiral fields were evolved in a finite temperature potential, incorporating the breaking of $U_A(1)$ symmetry. Initial random phases very quickly settle into oscillation around the values dictated by the potential. The simulation study indicate that an initial $\\Theta$=0 state do not evolve into a $\\Theta$ $\

  2. Thermally Fluctuating Second-Order Viscous Hydrodynamics and Heavy-Ion Collisions

    E-Print Network [OSTI]

    C. Young; J. I. Kapusta; C. Gale; S. Jeon; B. Schenke

    2014-07-03T23:59:59.000Z

    The fluctuation-dissipation theorem requires the presence of thermal noise in viscous fluids. The time and length scales of heavy ion collisions are small enough so that the thermal noise can have a measurable effect on observables. Thermal noise is included in numerical simulations of high energy lead-lead collisions, increasing average values of the momentum eccentricity and contributing to its event by event fluctuations.

  3. Estimate of the single diffractive heavy quark production in heavy ion collisions at the CERN LHC

    SciTech Connect (OSTI)

    Gay Ducati, M. B.; Machado, M. M. [High Energy Physics Phenomenology Group, GFPAE, IF-UFRGS, Caixa Postal 15051, CEP 91501-970, Porto Alegre, RS (Brazil); Machado, M. V. T. [Universidade Federal do Pampa. Centro de Ciencias Exatas e Tecnologicas, Campus de Bage, Rua Carlos Barbosa. CEP 96400-970. Bage, RS (Brazil)

    2010-03-01T23:59:59.000Z

    The single diffractive cross section for heavy quarks production is calculated at next-to-leading order (for nucleus-nucleus collisions. Such processes are expected to occur at the LHC, where the nuclei involved are lead at {radical}(s)=5.5 TeV and calcium at {radical}(s)=6.3 TeV. We start using the hard diffractive factorization formalism, taking into account a recent experimental parametrization for the Pomeron structure function (DPDF). Absorptive corrections are accounted for by the multiple Pomeron contributions considering a gap survival probability, where its theoretical uncertainty for nuclear collisions is discussed. We estimate the diffractive ratios for the single diffraction process in nuclear coherent/incoherent collisions at the LHC.

  4. Scaling of elliptic flow, recombination, and sequential freeze-out of hadrons in heavy-ion collisions

    E-Print Network [OSTI]

    He, Min; Fries, Rainer J.; Rapp, Ralf.

    2010-01-01T23:59:59.000Z

    The scaling properties of elliptic flow of hadrons produced in ultrarelativistic heavy-ion collisions are investigated at low transverse momenta, p(T) less than or similar to 2 GeV. Utilizing empirical parametrizations of a thermalized fireball...

  5. Dynamics in the production of superheavy nuclei in low-energy heavy-ion collisions

    E-Print Network [OSTI]

    Zhao-Qing Feng; Gen-Ming Jin; Jun-Qing Li

    2011-05-27T23:59:59.000Z

    We present a review of the recent progress of theoretical models on the description of the formation of superheavy nuclei in collisions of heavy systems. Two sorts of reactions that are the fusion-evaporation mechanism and the massive damped collisions to produce superheavy nuclei are discussed. Problems and further improvements of the capture of colliding partners, the formation of compound nucleus and the de-excitation process are pointed out. Possible combinations in the synthesis of the gap of the cold fusion and $^{48}$Ca induced reactions are proposed by the calculations based on the dinuclear system model and also compared with other approaches. The synthesis of neutron-rich heavy isotopes near sub-shell closure N=162 via transfer reactions in the damped collisions of two actinides and the influence of shell closure on the production of heavy isotopes are investigated. Prospective possibility to reach superheavy nuclei near N=184 via neutron-rich radioactive beams of high intensity in the future is discussed.

  6. Dynamics in the production of superheavy nuclei in low-energy heavy-ion collisions

    E-Print Network [OSTI]

    Feng, Zhao-Qing; Jin, Jun-Qing

    2011-01-01T23:59:59.000Z

    We present a review of the recent progress of theoretical models on the description of the formation of superheavy nuclei in collisions of heavy systems. Two sorts of reactions that are the fusion-evaporation mechanism and the massive damped collisions to produce superheavy nuclei are discussed. Problems and further improvements of the capture of colliding partners, the formation of compound nucleus and the de-excitation process are pointed out. Possible combinations in the synthesis of the gap of the cold fusion and $^{48}$Ca induced reactions are proposed by the calculations based on the dinuclear system model and also compared with other approaches. The synthesis of neutron-rich heavy isotopes near sub-shell closure N=162 via transfer reactions in the damped collisions of two actinides and the influence of shell closure on the production of heavy isotopes are investigated. Prospective possibility to reach superheavy nuclei near N=184 via neutron-rich radioactive beams of high intensity in the future is dis...

  7. Coupled-Channel Effects in Collisions between Heavy Ions near the Coulomb Barrier

    E-Print Network [OSTI]

    Beck, C

    2013-01-01T23:59:59.000Z

    With the recent availability of state-of-the-art heavy-ion stable and radioactive beams, there has been a renew interest in the investigation of nuclear reactions with heavy ions. I first present the role of inelastic and transfer channel couplings in fusion reactions induced by stable heavy ions. Analysis of experimental fusion cross sections by using standard coupled-channel calculations is discussed. The role of multi-neutron transfer is investigated in the fusion process below the Coulomb barrier by analyzing $^{32}$S+$^{90,96}$Zr as benchmark reactions. The enhancement of fusion cross sections for $^{32}$S+$^{96}$Zr is well reproduced at sub-barrier energies by NTFus code calculations including the coupling of the neutron-transfer channels following the Zagrebaev semi-classical model. Similar effects for $^{40}$Ca+$^{90}$Zr and $^{40}$Ca+$^{96}$Zr fusion excitation functions are found. The breakup coupling in both the elastic scattering and in the fusion process induced by weakly bound stable projectiles...

  8. Coupled-Channel Effects in Collisions between Heavy Ions near the Coulomb Barrier

    E-Print Network [OSTI]

    C. Beck

    2012-05-21T23:59:59.000Z

    With the recent availability of state-of-the-art heavy-ion stable and radioactive beams, there has been a renew interest in the investigation of nuclear reactions with heavy ions. I first present the role of inelastic and transfer channel couplings in fusion reactions induced by stable heavy ions. Analysis of experimental fusion cross sections by using standard coupled-channel calculations is discussed. The role of multi-neutron transfer is investigated in the fusion process below the Coulomb barrier by analyzing $^{32}$S+$^{90,96}$Zr as benchmark reactions. The enhancement of fusion cross sections for $^{32}$S+$^{96}$Zr is well reproduced at sub-barrier energies by NTFus code calculations including the coupling of the neutron-transfer channels following the Zagrebaev semi-classical model. Similar effects for $^{40}$Ca+$^{90}$Zr and $^{40}$Ca+$^{96}$Zr fusion excitation functions are found. The breakup coupling in both the elastic scattering and in the fusion process induced by weakly bound stable projectiles is also shown to be crucial. In this lecture, full coupled-channel calculations of the fusion excitation functions are performed by using the breakup coupling for the more neutron-rich reaction and for the more weakly bound projectiles. I clearly demonstrate that Continuum-Discretized Coupled-Channel calculations are capable to reproduce the fusion enhancement from the breakup coupling in $^{6}$Li+$^{59}$Co.

  9. Rho0 Photoproduction in Ultra-Peripheral Relativistic Heavy Ion Collisions with STAR

    SciTech Connect (OSTI)

    STAR Coll

    2007-12-20T23:59:59.000Z

    Photoproduction reactions occur when the electromagnetic field of a relativistic heavy ion interacts with another heavy ion. The STAR collaboration presents a measurement of {rho}{sup 0} and direct {pi}{sup +}{pi}{sup -} photoproduction in ultra-peripheral relativistic heavy ion collisions at {radical}s{sub NN} = 200 GeV. We observe both exclusive photoproduction and photoproduction accompanied by mutual Coulomb excitation. We find a coherent cross-section of {sigma}(AuAu {yields} Au*Au* {rho}{sup 0}) = 530 {+-} 19 (stat.) {+-} 57 (syst.) mb, in accord with theoretical calculations based on a Glauber approach, but considerably below the predictions of a color dipole model. The {rho}{sup 0} transverse momentum spectrum (p{sub T}{sup 2}) is fit by a double exponential curve including both coherent and incoherent coupling to the target nucleus; we find {sigma}{sub inc}/{sigma}{sub coh} = 0.29 {+-} 0.03 (stat.) {+-} 0.08 (syst.). The ratio of direct {pi}{sup +}{pi}{sup -} production is comparable to that observed in {gamma}p collisions at HERA, and appears to be independent of photon energy. Finally, the measured {rho}{sup 0} spin helicity matrix elements agree within errors with the expected s-channel helicity conservation.

  10. Development of a heavy-ion identification method using a combined time-of-flight [delta]E-E technique

    E-Print Network [OSTI]

    Hanus, Roy Gene

    1976-01-01T23:59:59.000Z

    Nagatani Identification of heavy-ion reaction products produced at the Texas A&H Variable Energy Cyclotron has been done primarily through the use of the AE-E detector telescope technique. The telescope is formed by placing two detectors together... of the partzcles eo their total initial energy, they can uniquely be identified. However, this technique for identification of heavy-ion reaction prod- ucts is adequate only for isotopes up through those of oxygen. Beyond oxygen, only element identification can...

  11. Radiation damage by light- and heavy-ion bombardment of single-crystal LiNbO?

    SciTech Connect (OSTI)

    Huang, Hsu-Cheng [Columbia Univ., New York, NY (United States); Zhang, Lihua [Brookhaven National Lab. (BNL), Upton, NY (United States); Malladi, Girish [SUNY Polytechnic Inst., Albany, NY (United States); Dadap, Jerry I. [Columbia Univ., New York, NY (United States); Manandhar, Sandeep [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Kisslinger, Kim [Brookhaven National Lab. (BNL), Upton, NY (United States); Vemuri, Rama Sesha R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Shutthanandan, Vaithiyalingam [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Bakhru, Hassaram [SUNY Polytechnic Inst., Albany, NY (United States); Osgood, Jr., Richard M. [Columbia Univ., New York, NY (United States)

    2015-01-01T23:59:59.000Z

    In this work, a battery of analytical methods including in situ RBS/C, confocal micro-Raman, TEM/STEM, EDS, AFM, and optical microscopy were used to provide a comparative investigation of light- and heavy-ion radiation damage in single-crystal LiNbO?. High (~MeV) and low (~100s keV) ion energies, corresponding to different stopping power mechanisms, were used and their associated damage events were observed. In addition, sequential irradiation of both ion species was also performed and their cumulative depth-dependent damage was determined. It was found that the contribution from electronic stopping by high-energy heavy ions gave rise to a lower critical fluence for damage formation than for the case of low-energy irradiation. Such energy-dependent critical fluence of heavy-ion irradiation is two to three orders of magnitude smaller than that for the case of light-ion damage. In addition, materials amorphization and collision cascades were seen for heavy-ion irradiation, while for light ion, crystallinity remained at the highest fluence used in the experiment. The irradiation-induced damage is characterized by the formation of defect clusters, elastic strain, surface deformation, as well as change in elemental composition. In particular, the presence of nanometric-scale damage pockets results in increased RBS/C backscattered signal and the appearance of normally forbidden Raman phonon modes. The location of the highest density of damage is in good agreement with SRIM calculations. (author)

  12. Progress in heavy ion driven inertial fusion energy: From scaledexperiments to the integrated research experiment

    SciTech Connect (OSTI)

    Barnard, J.J.; Ahle, L.E.; Baca, D.; Bangerter, R.O.; Bieniosek,F.M.; Celata, C.M.; Chacon-Golcher, E.; Davidson, R.C.; Faltens, A.; Friedman, A.; Franks, R.M.; Grote, D.P.; Haber, I.; Henestroza, E.; deHoon, M.J.L.; Kaganovich, I.; Karpenko, V.P.; Kishek, R.A.; Kwan, J.W.; Lee, E.P.; Logan, B.G.; Lund, S.M.; Meier, W.R.; Molvik, A.W.; Olson, C.; Prost, L.R.; Qin, H.; Rose, D.; Sabbi, G-L.; Sangster, T.C.; Seidl, P.A.; Sharp, W.M.; Shuman, D.; Vay, J.L.; Waldron, W.L.; Welch, D.; Yu, S.S.

    2001-06-22T23:59:59.000Z

    The promise of inertial fusion energy driven by heavy ion beams requires the development of accelerators that produce ion currents ({approx}100s Amperesheam) and ion energies ({approx}1-10 GeV) that have not been achieved simultaneously in any existing accelerator. The high currents imply high generalized perveances, large tune depressions. and high space charge potentials of the beam center relative to the beam pipe. Many of the scientific issues associated with ion beams of high perveance and large tune depression have been addressed over the last two decades on scaled experiments at Lawrence Berkeley and Lawrence Livermore National Laboratories, the University of Maryland, and elsewhere. The additional requirement of high space charge potential (or equivalently high line charge density) gives rise to effects (particularly the role of electrons in beam transport) which must be understood before proceeding to a large scale accelerator. The first phase of a new series of experiments in Heavy Ion Fusion Virtual National Laboratory (HIF VNL), the High Current Experiments (HCX), is now being constructed at LBNL. The mission of the HCX will be to transport beams with driver line charge density so as to investigate the physics of this regime, including constraints on the maximum radial filling factor of the beam through the pipe. This factor is important for determining both cost and reliability of a driver scale accelerator. The HCX will provide data for design of the next steps in the sequence of experiments leading to an inertial Fusion energy power plant. The focus of the program after the HCX will be on integration of all of the manipulations required for a driver. In the near term following HCX, an Integrated Beam Experiment (IBX) of the same general scale as the HCX is envisioned.

  13. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    SciTech Connect (OSTI)

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. (Alabama Univ., University, AL (United States). Mineral Resources Inst.)

    1991-01-01T23:59:59.000Z

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  14. Removal of heavy metal ions from oil shale beneficiation process water by ferrite process

    SciTech Connect (OSTI)

    Mehta, R.K.; Zhang, L.; Lamont, W.E.; Schultz, C.W. [Alabama Univ., University, AL (United States). Mineral Resources Inst.

    1991-12-31T23:59:59.000Z

    The ferrite process is an established technique for removing heavy metals from waste water. Because the process water resulting from oil shale beneficiation falls into the category of industrial waste water, it is anticipated that this process may turn out to be a potential viable treatment for oil shale beneficiation process water containing many heave metal ions. The process is chemoremedial because not only effluent water comply with quality standards, but harmful heavy metals are converted into a valuable, chemically stable by-product known as ferrite. These spinel ferrites have magnetic properties, and therefore can be use in applications such as magnetic marker, ferrofluid, microwave absorbing and scavenging material. Experimental results from this process are presented along with results of treatment technique such as sulfide precipitation.

  15. fcc-hcp phase transformation in Co nanoparticles induced by swift heavy-ion irradiation

    SciTech Connect (OSTI)

    Sprouster, D. J.; Giulian, R.; Schnohr, C. S.; Araujo, L. L.; Kluth, P.; Byrne, A. P.; Foran, G. J.; Johannessen, B.; Ridgway, M. C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Department of Physics, Faculty of Science, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Australian Nuclear Science and Technology Organization, Menai, New South Wales 2234 (Australia); Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2009-09-15T23:59:59.000Z

    We demonstrate a face-centered cubic (fcc) to hexagonally close-packed (hcp) phase transformation in spherical Co nanoparticles achieved via swift heavy-ion irradiation. Co nanoparticles of mean diameter 13.2 nm and fcc phase were first formed in amorphous SiO{sub 2} by ion implantation and thermal annealing and then irradiated at room temperature with 9-185 MeV Au ions. The crystallographic phase was identified with x-ray absorption spectroscopy and electron diffraction and quantified, as functions of the irradiation energy and fluence, with the former. The transformation was complete at low fluence prior to any change in nanoparticle shape or size and was governed by electronic stopping. A direct-impact mechanism was identified with the transformation interaction cross-section correlated with that of a molten ion track in amorphous SiO{sub 2}. We suggest the shear stress resulting from the rapid thermal expansion about an ion track in amorphous SiO{sub 2} was sufficient to initiate the fcc-to-hcp phase transformation in the Co nanoparticles.

  16. Investigation of the specific plasma potential oscillations with geodesic acoustic mode frequencies by heavy ion beam probing in the T-10 tokamak

    E-Print Network [OSTI]

    Paris-Sud XI, Université de

    by heavy ion beam probing in the T-10 tokamak A V Melnikov1 , L G Eliseev1 , A V Gudozhnik1 , S E Lysenko1 of the specific oscillations with frequencies 15-30 kHz on the T-10 tokamak (R= 150cm, a = 30 cm) with Heavy IonHz) have been discovered in the tokamak by Heavy Ion Beam Probe (HIBP) diagnostic in 1993 [1, 2]. During

  17. 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.

    2002-01-01T23:59:59.000Z

    experiments at RHIC at Brookhaven National Laboratory, where the colli- sion energy is much higher than at SPS, have also shown possible effects due to the formation of a partonic matter @4#. To find the signal for the quark-gluon plasma in relativis- tic... in the hadronic matter @11?18#. The observed abnormal suppres- sion of J/c in central Pb1Pb collisions at SPS may require the formation of the quark-gluon plasma in these collisions @19,3#. For heavy ion collisions at RHIC energies, unlike in pre- vious fixed...

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

    E-Print Network [OSTI]

    Lin, ZW; Ko, Che Ming.

    2002-01-01T23:59:59.000Z

    to obtain an elliptic flow that is comparable to the measured ones in heavy ion collisions at both SPS and RHIC energies @18#. In transport models including only the parton cascade, the elliptic flow has been shown to be sensitive to the parton... scattering cross section, and a large value can be obtained with a large cross section @20,21#. On the other hand, transport models based on hadronic and/or string de- grees of freedom in general give a smaller elliptic flow @9# than that observed at RHIC...

  19. Nuclear polarization study: New frontiers for tests of QED in heavy highly charged ions

    E-Print Network [OSTI]

    Volotka, Andrey V

    2015-01-01T23:59:59.000Z

    A systematic investigation of the nuclear-polarization effects in one- and few-electron heavy ions is presented. The nuclear-polarization corrections in the zeroth and first orders in $1/Z$ are evaluated to the binding energies, the hyperfine splitting, and the bound-electron g factor. It is shown, that the nuclear-polarization contributions can be substantially canceled simultaneously with the rigid nuclear corrections. This allows for new prospects for probing the QED effects in strong electromagnetic field and the determination of fundamental constants.

  20. Relativistic Vlasov-Uehling-Uhlenbeck Model for Heavy-Ion Collisions

    E-Print Network [OSTI]

    Ko, Che Ming; LI, Q.

    1988-01-01T23:59:59.000Z

    , Q. Li, and R. Wang, Phys. Rev. Lett. 59, 1084 (1987). zJ. D. Walecka, Ann. Phys. $3, 491 (1974). 3H. Elze et al. , Mod. Phys. Lett. 2, 451 (1987). 4Q. Li and C. M. Ko, Mod. Phys. Lett. (to be published). SR. Y. Cusson et al. , Phys. Rev. Lett.... 55, 2786 (1985). 6G. F. Bertsch, H. Kruse, and S. Das Gupta, Phys. Rev. C 29, 673 (1984). 78. ter Haar and R. Malfliet, Phys. Rep. 149, 207 (1987). G. E. Brown, in Proceedings of the Eighth High Energy Heavy ion Study, Berkeley, California, 1987...

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

    E-Print Network [OSTI]

    Ko, Che Ming.

    1984-01-01T23:59:59.000Z

    energy spectrum can also be understood qualitatively. ' There is another process NY ?+NNK which may also contribute to the production of antikaons in heavy-ion collisions. Since the threshold energies for this process are -455 MeV and -635 MeV for Y...=X and Y=A, respectively, and are larger than those for the process m Y?+KN, which are ?120 MeV and -215 MeV for Y=X and Y=A, respectively, one might intuitively think that the contribution from the reaction NY~NNK is negligible. To ensure...

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

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

    Jia, Jiangyong [Stony Brook Univ., NY (United States). Dept. of Chemistry; Brookhaven National Lab., Upton, NY (United States). Physics Dept.

    2014-12-01T23:59:59.000Z

    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.

  3. Jet Quenching in High Energy Heavy Ion Collisions by QCD Synchrotron-like Radiation

    E-Print Network [OSTI]

    E. V. Shuryak; I. Zahed

    2002-07-12T23:59:59.000Z

    We consider synchrotron-like radiation in QCD by generalizing Schwinger's treatment of quantum synchrotron radiation in QED to the case of a constant chromomagnetic field. We suggest a novel mechanism for {\\em jet quenching} in heavy ion collisions, whereby high-$p_t$ partons get depleted through strong (classical) color fields. The latters are encountered in the color glass condensate or in the form of expanding shells of exploding sphalerons. Unlike bremsstrahlung radiation through multiple soft rescattering, synchrotron radiation converts a jet into a wide shower of soft gluons. We estimate the energy loss through this mechanism and suggest that it contributes significantly to the unexpectedly strong jet quenching observed at RHIC.

  4. Direct photon emission in Heavy Ion Collisions from Microscopic Transport Theory and Fluid Dynamics

    E-Print Network [OSTI]

    Bjoern Baeuchle; Marcus Bleicher

    2010-03-29T23:59:59.000Z

    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.

  5. K+ production in baryon-baryon and heavy-ion collisions 

    E-Print Network [OSTI]

    Li, GQ; Ko, Che Ming; Chung, WS.

    1998-01-01T23:59:59.000Z

    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....

  6. Production Cross Section of Neutron-Rich Calcium Isotopes in Heavy Ion Collisions

    E-Print Network [OSTI]

    Donghong Zhang; Wenjie Xie; Jun Su; Fengshou Zhang

    2015-03-27T23:59:59.000Z

    Based on the isospin-dependent quantum molecular dynamics model along with the GEMINI model, heavy-ion collisions at intermediate energies are studied. We calculate the production cross sections of different fragments for reactions of 112Sn+112Sn and 124Sn+124Sn at different beam energies. The species and production cross sections of neutron-rich isotopes are generally dependent on the isospin of the system and the incident energies. The nucleon 48Ca and 54Ca are more productive for the neutron-rich system at 30 to 150 MeV/nucleon.

  7. Interplay between compound and fragments aspects of nuclear fission and heavy-ion reaction

    SciTech Connect (OSTI)

    Moller, Peter [Los Alamos National Laboratory; Iwamoto, A [JAPAN; Ichikawa, I [JAPAN

    2010-09-10T23:59:59.000Z

    The scission point in nuclear fission plays a special role where one-body system changes to two-body system. Inverse of this situation is realized in heavy-ion fusion reaction where two-body system changes to one body system. Among several peculiar phenomena expected to occur during this change, we focus our attention to the behavior of compound and fragments shell effects. Some aspects of the interplay between compound and fragments shell effect are discussed related to the topics of the fission valleys in the potential energy surface of actinide nuclei and the fusion-like trajectory found in the cold fusion reaction leading to superheavy nuclei.

  8. Time-Depentent Hartree-Fock description of heavy ions fusion

    E-Print Network [OSTI]

    Cédric Simenel; Benoît Avez

    2007-11-06T23:59:59.000Z

    A microscopic mean-field description of heavy ions fusion is performed in the framework of the Time-Dependent Hartree-Fock (TDHF) theory using a Skyrme interaction with the SLy4d parametrization. A good agreement with experiments is obtained on the position of the fusion barriers for various total masses, mass asymmetries and deformations. The excitation function of the 16O+208Pb is overestimated by about 16% above the barrier. The restriction to an independent particles state in the mean-field dynamics prevents the description of sub-barrier fusion. Effect of transfer on fusion is discussed.

  9. A Ghoshal-like Test of Equilibration in Near-Fermi-Energy Heavy Ion Collisions

    E-Print Network [OSTI]

    J. Wang; T. Keutgen; R. Wada; K. Hagel; Y. G. Ma; M. Murray; L. Qin; P. Smith; J. B. Natowitz; R. Alfaro; J. Cibor; A. Botvina; M. Cinausero; Y. El Masri; D. Fabris; A. Keksis; S. Kowalski; M. Lunardon; A. Makeev; N. Marie; E. Martin; Z. Majka; A. Martinez-Davalos; A. Menchaca-Rocha; G. Nebbia; S. Moretto; G. Prete; V. Rizzi; A. Ruangma; D. V. Shetty; G. Souliotis; P. Staszel; M. Veselsky; G. Viesti; E. M. Winchester; S. J. Yennello; W. Zipper; A. Ono

    2004-12-22T23:59:59.000Z

    Calorimetric and coalescence techniques have been employed to probe equilibration for hot nuclei produced in heavy ion collisions of 35 to 55 MeV/u projectiles with medium mass targets. Entrance channel mass asymmetries and energies were selected in order that very hot composite nuclei of similar mass and excitation would remain after early stage pre-equilibrium particle emission. Inter-comparison of the properties and de-excitation patterns for these different systems provides evidence for the production of hot nuclei with decay patterns relatively independent of the specific entrance channel.

  10. Production of Anticentauro Events in Ultra-Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    G. Sood

    2007-04-10T23:59:59.000Z

    We propose a novel method for studying the production of anticentauro events in high energy heavy ion collisions utilizing Chebyshev expansion coefficients. These coefficients have proved to be very efficient in investigating the pattern of fluctuations in neutral pion fraction. For the anticentauro like events, the magnitude of first few coefficients is strongly enhanced (~3 times) as compared to those of normal HIJING events. Various characteristics of Chebyshev coefficients are studied in detail and the probability of formation of exotic events is calculated from the simulated events.

  11. Rapidity losses in heavy-ion collisions from AGS to RHIC energies

    E-Print Network [OSTI]

    F. C. Zhou; Z. B. Yin; D. C. Zhou

    2009-09-28T23:59:59.000Z

    We study the rapidity losses in central heavy-ion collisions from AGS to RHIC energies with the mean rapidity determined from the projectile net-baryon distribution after collisions. The projectile net-baryon distribution in the full rapidity range was obtained by removing the target contribution phenomenologically at forward rapidity region from the experimental net-baryon measurements and taking into account the projectile contribution at backward rapidity region. Based on the full projectile net-baryon distributions, calculation results show that the rapidity loss stops increasing from the SPS top energy to RHIC energies, indicating that baryon transport does not depend strongly on energy at high energies.

  12. Glauber model for heavy ion collisions from low energies to high energies

    E-Print Network [OSTI]

    P. Shukla

    2001-12-13T23:59:59.000Z

    The Glauber model is extensively applied to heavy ion collision for describing a number of interaction processes over a wide range of energies from near the Coulomb barrier to higher energies. The model gives the nucleus-nucleus interaction in terms of interaction between the constituent nucleons with a given density distribution. The model is a semiclassical model picturing the nuclear collision in the impact parameter representation where the nuclei move along the collision direction in a straight path. In these lectures we derive this model and discuss its applications in variety of problems in nuclear and high energy physics.

  13. Interferometric signatures of the temperature dependence of the specific shear viscosity in heavy-ion collisions

    E-Print Network [OSTI]

    Christopher Plumberg; Ulrich Heinz

    2015-04-08T23:59:59.000Z

    Recent work has shown that a temperature dependence of the shear viscosity to entropy ratio, $\\eta/s$, influences the collective flow pattern in heavy-ion collisions in characteristic ways that can be measured by studying hadron transverse momentum spectra and their anisotropies. Here we point out that it also affects the pair momentum dependence of the Hanbury-Brown$-$Twiss (HBT) radii (the source size parameters extracted from two-particle intensity interferometry) and the variance of their event-by-event fluctuations. This observation establishes interferometric signatures as useful observables to complement the constraining power of single-particle spectra on the temperature dependence of $\\eta/s$.

  14. Bulk viscosity-driven freeze-out in heavy ion collisions

    E-Print Network [OSTI]

    Giorgio Torrieri; Igor Mishustin; Boris Tomášik

    2009-01-02T23:59:59.000Z

    We give an review the HBT puzzle, and argue that its resolution requires the introduction of new physics close to the phase transition scale. We argue that a candidate for this new physics is bulk viscosity, recently postulated to peak, and even diverge, close to the phase transition temperature. We show that such a viscosity peak can force the system created in heavy ion collisions to become unstable, and filament into fragments whose size is weakly dependent on the global size of the system, thereby triggering freeze-out.

  15. Interferometric signatures of the temperature dependence of the specific shear viscosity in heavy-ion collisions

    E-Print Network [OSTI]

    Plumberg, Christopher

    2015-01-01T23:59:59.000Z

    Recent work has shown that a temperature dependence of the shear viscosity to entropy ratio, $\\eta/s$, influences the collective flow pattern in heavy-ion collisions in characteristic ways that can be measured by studying hadron transverse momentum spectra and their anisotropies. Here we point out that it also affects the pair momentum dependence of the Hanbury-Brown$-$Twiss (HBT) radii (the source size parameters extracted from two-particle intensity interferometry) and the variance of their event-by-event fluctuations. This observation establishes interferometric signatures as useful observables to complement the constraining power of single-particle spectra on the temperature dependence of $\\eta/s$.

  16. Anomalous transport effects and possible environmental symmetry "violation" in heavy ion collisions

    E-Print Network [OSTI]

    Jinfeng Liao

    2015-02-27T23:59:59.000Z

    The heavy ion collision provides a unique many-body environment where local domains of strongly interacting chiral medium may occur and in a sense allow environmental symmetry "violation" phenomena. For example certain anomalous transport processes, forbidden in usual medium, become possible in such domains. We briefly review recent progress in both the theoretical understanding and experimental search of various anomalous transport effects (such as the Chiral Magnetic Effect, Chiral Separation Effect, Chiral Electric Separation Effect, Chiral Electric/Magnetic Waves, etc) in the hot QCD fluid created by such collisions.

  17. Free magnetized knots of parity-violating deconfined matter in heavy-ion collisions

    E-Print Network [OSTI]

    M. N. Chernodub

    2010-02-07T23:59:59.000Z

    We show that the local parity violation in the quark-gluon plasma supports existence of free (meta)stable knots of deconfined hot quark matter stabilized by superstrong magnetic fields. The magnetic field in the knots resembles the spheromak plasma state of the magnetic confinement approach to nuclear fusion. The size of the knot is quantized, being inversely proportional to the chiral conductivity of the quark-gluon plasma. The parity symmetry is broken inside the knot. Particles produced in the decays of the knots have unusual azimuthal distribution and specific flavor content. We argue that these knots may be created in noncentral heavy-ion collisions.

  18. Free magnetized knots of parity-violating deconfined matter in heavy-ion collisions

    E-Print Network [OSTI]

    Chernodub, M N

    2010-01-01T23:59:59.000Z

    We show that the local parity violation in the quark-gluon plasma supports existence of free (meta)stable knots of deconfined hot quark matter stabilized by superstrong magnetic fields. The magnetic field in the knots resembles the spheromak plasma state of the magnetic confinement approach to nuclear fusion. The size of the knot is quantized, being inversely proportional to the chiral conductivity of the quark-gluon plasma. The parity symmetry is broken inside the knot. Particles produced in the decays of the knots have unusual azimuthal distribution and specific flavor content. We argue that these knots may be created in noncentral heavy-ion collisions.

  19. K+ production in baryon-baryon and heavy-ion collisions

    E-Print Network [OSTI]

    Li, GQ; Ko, Che Ming; Chung, WS.

    1998-01-01T23:59:59.000Z

    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....

  20. Recent results from HADES on electron pair production in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    The HADES Collaboration; T. Galatyuk; G. Agakishiev; A. Balanda; D. Belver; A. V. Belyaev; A. Blanco; M. Böhmer; J. L. Boyard; P. Braun-Munzinger; P. Cabanelas; E. Castro; S. Chernenko; T. Christ; M. Destefanis; J. Díaz; F. Dohrmann; A. Dybczak; L. Fabbietti; O. V. Fateev; P. Finocchiaro; P. Fonte; J. Friese; I. Fröhlich; J. A. Garzón; R. Gernhäuser; A. Gil; C. Gilardi; M. Golubeva; D. González-Díaz; F. Guber; T. Hennino; R. Holzmann; I. Iori; A. Ivashkin; M. Jurkovic; B. Kämpfer; T. Karavicheva; D. Kirschner; I. Koenig; W. Koenig; B. W. Kolb; R. Kotte; F. Krizek; R. Krücken; W. Kühn; A. Kugler; A. Kurepin; S. Lang; J. S. Lange; K. Lapidus; T. Liu; L. Lopes; M. Lorenz; L. Maier; A. Mangiarotti; J. Markert; V. Metag; B. Michalska; J. Michel; E. Morinière; J. Mousa; C. Müntz; L. Naumann; J. Otwinowski; Y. C. Pachmayer; M. Palka; Y. Parpottas; V. Pechenov; O. Pechenova; J. Pietraszko; W. Przygoda; B. Ramstein; A. Reshetin; A. Rustamov; A. Sadovsky; P. Salabura; A. Schmah; E. Schwab; Yu. G. Sobolev; S. Spataro; B. Spruck; H. Ströbele; J. Stroth; C. Sturm; M. Sudol; A. Tarantola; K. Teilab; P. Tlusty; M. Traxler; R. Trebacz; H. Tsertos; V. Wagner; M. Weber; M. Wisniowski; T. Wojcik; J. Wüstenfeld; S. Yurevich; Y. V. Zanevsky; P. Zhou

    2009-11-12T23:59:59.000Z

    Systematic investigations of dilepton production are performed at the SIS accelerator of GSI with the HADES spectrometer. The goal of this program is a detailed understanding of di-electron emission from hadronic systems at moderate temperatures and densities. New results obtained in HADES experiments focussing on electron pair production in elementary collisions are reported here. They pave the way to a better understanding of the origin of the so-called excess pairs earlier on observed in heavy-ion collisions by the DLS collaboration and lately confirmed in two measurements of the HADES collaboration using C+C and Ar+KCl collisions. Results of these studies are discussed.

  1. Amorphization of crystalline Si due to heavy and light ion irradiation

    SciTech Connect (OSTI)

    Edmondson, P. D.; Riley, D. J.; Donnelly, S. E. [Institute for Materials Research, University of Salford, Manchester M5 4WT (United Kingdom); Birtcher, R. C. [Materials Science Division, Argonne National Laboratory, Argonne, Illinois 60439 (United States)

    2009-08-15T23:59:59.000Z

    The formation of amorphous silicon in crystalline silicon by bombardment with light (Si) and heavy (Xe) ions has been investigated by transmission electron microscopy with in situ ion irradiation. Experiments have been carried out at room temperature and low temperature (50 K) and the results are compared to a simple numerical model for amorphization. The results indicate that the amorphization mechanisms for both irradiations are heterogeneous in nature and that numerous overlaps of the collision cascade are generally required to render the crystal amorphous. Following from this, the nature of the material within the confines of collision cascades will be discussed and it will be shown that the individual cascade volume is not necessarily amorphous as previously described in the scientific literature but contains varying degrees of damage depending on the energy deposited within the cascade.

  2. Amorphization of crystalline Si due to heavy and light ion irradiation.

    SciTech Connect (OSTI)

    Edmondson, P. D.; Riley, D. J.; Birtcher, R. C.; Donnelly, S. E.; Materials Science Division; Univ. of Salford

    2009-08-01T23:59:59.000Z

    The formation of amorphous silicon in crystalline silicon by bombardment with light (Si) and heavy (Xe) ions has been investigated by transmission electron microscopy with in situ ion irradiation. Experiments have been carried out at room temperature and low temperature (50 K) and the results are compared to a simple numerical model for amorphization. The results indicate that the amorphization mechanisms for both irradiations are heterogeneous in nature and that numerous overlaps of the collision cascade are generally required to render the crystal amorphous. Following from this, the nature of the material within the confines of collision cascades will be discussed and it will be shown that the individual cascade volume is not necessarily amorphous as previously described in the scientific literature but contains varying degrees of damage depending on the energy deposited within the cascade.

  3. Off-momentum dynamic aperture for lattices in the RHIC heavy ion runs

    SciTech Connect (OSTI)

    Luo Y.; Bai, M.; Blaskiewicz, M.; Gu, X.; Fischer, W.; Marusic, A.; Roser, T.; Tepikian, S.; Zhang, S.

    2012-05-20T23:59:59.000Z

    To reduce transverse emittance growth rates from intrabeam scattering in the RHIC heavy ion runs, a lattice with an increased phase advance in the arc FODO cells was adopted in 2008-2011. During these runs, a large beam loss due to limited off-momentum dynamic aperture was observed during longitudinal RF re-bucketing and with transverse cooling. Based on the beam loss observations in the previous ion runs and the calculated off-momentum apertures, we decided to adopt the lattice used before 2008 for the 2012 U-U and Cu-Au runs. The observed beam decay and the measured momentum aperture in the 2012 U-U run are presented.

  4. A Cone Jet-Finding Algorithm for Heavy-Ion Collisions at LHC Energies

    E-Print Network [OSTI]

    S-L Blyth; M J Horner; T Awes; T Cormier; H Gray; J L Klay; S R Klein; M van Leeuwen; A Morsch; G Odyniec; A Pavlinov

    2006-09-15T23:59:59.000Z

    Standard jet finding techniques used in elementary particle collisions have not been successful in the high track density of heavy-ion collisions. This paper describes a modified cone-type jet finding algorithm developed for the complex environment of heavy-ion collisions. The primary modification to the algorithm is the evaluation and subtraction of the large background energy, arising from uncorrelated soft hadrons, in each collision. A detailed analysis of the background energy and its event-by-event fluctuations has been performed on simulated data, and a method developed to estimate the background energy inside the jet cone from the measured energy outside the cone on an event-by-event basis. The algorithm has been tested using Monte-Carlo simulations of Pb+Pb collisions at $\\sqrt{s}=5.5$ TeV for the ALICE detector at the LHC. The algorithm can reconstruct jets with a transverse energy of 50 GeV and above with an energy resolution of $\\sim30%$.

  5. Heavy Ion physics with the ALICE experiment at the CERN LHC

    E-Print Network [OSTI]

    J. Schukraft; for the ALICE Collaboration

    2011-09-20T23:59:59.000Z

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

  6. Microscopic dynamics simulations of heavy-ion fusion reactions induced by neutron-rich nuclei

    E-Print Network [OSTI]

    Ning Wang; Li Ou; Yingxun Zhang; Zhuxia Li

    2014-06-04T23:59:59.000Z

    The heavy-ion fusion reactions induced by neutron-rich nuclei are investigated with the improved quantum molecular dynamics (ImQMD) model. With a subtle consideration of the neutron skin thickness of nuclei and the symmetry potential, the stability of nuclei and the fusion excitation functions of heavy-ion fusion reactions $^{16}$O+$^{76}$Ge, $^{16}$O+$^{154}$Sm, $^{40}$Ca+$^{96}$Zr and $^{132}$Sn+$^{40}$Ca are systematically studied. The fusion cross sections of these reactions at energies around the Coulomb barrier can be well reproduced by using the ImQMD model. The corresponding slope parameter of the symmetry energy adopted in the calculations is $L \\approx 78$ MeV and the surface energy coefficient is $g_{\\rm sur}=18\\pm 1.5$ MeVfm$^2$. In addition, it is found that the surface-symmetry term significantly influences the fusion cross sections of neutron-rich fusion systems. For sub-barrier fusion, the dynamical fluctuations in the densities of the reaction partners and the enhanced surface diffuseness at neck side result in the lowering of the fusion barrier.

  7. Centrality dependence of strangeness enhancement in ultrarelativistic heavy ion collisions: A core-corona effect

    SciTech Connect (OSTI)

    Aichelin, J.; Werner, K. [SUBATECH, Laboratoire de Physique Subatomique et des Technologies Associees, Universite de Nantes, IN2P3/CNRS, Ecole des Mines de Nantes, 4 rue Alfred Kastler, F-44072 Nantes, Cedex 03 (France)

    2009-06-15T23:59:59.000Z

    In ultrarelativistic heavy ion collisions, the multiplicity of multistrange baryons per participating nucleon increases with centrality in a different fashion for different systems and energies. At RHIC, for copper+copper (CuCu) collisions the increase is much steeper than for gold-gold (AuAu) collisions. We show that this system size dependence is due to a core-corona effect: the relative importance of the corona as compared to the core (thermalized matter) contribution varies and the contribution of a corona nucleon to the multiplicity differs from that of a core nucleon. {phi} mesons follow--as all hadrons--the same trend, but the difference between core and corona multiplicity is relatively small, and therefore the CuCu and AuAu results are quite similar. This simple geometrical explanation makes also a strong case in favor of the validity of Glauber geometry in the peripheral regions of ultrarelativistic heavy ion collisions, which is crucial for understanding the early evolution of the system.

  8. Centrality Dependence of Strangeness Enhancement in Ultrarelativistic Heavy Ion Collisions - a Core-Corona Effect

    E-Print Network [OSTI]

    J. Aichelin; K. Werner

    2009-05-19T23:59:59.000Z

    In ultrarelativistic heavy ion collisions, the multiplicity of multi-strange baryons per participating nucleon increases with centrality in a different fashion for different systems and energies. At RHIC, for copper+copper (CuCu) collisions the increase is much steeper than for gold-gold (AuAu) collisions. We show that this system size dependence is due to a core-corona effect: the relative importance of the corona as compared to the core (thermalized matter) contribution varies and the contribution of a corona nucleon to the multiplicity differs from that of a core nucleon. $\\phi$ mesons follow in principle the same trend, but the difference between core and corona multiplicity is relatively small, and therefore the CuCu and AuAu results are quite similar. This simple geometrical explanation makes also a strong case in favor of the validity of Glauber geometry in the peripheral regions of ultrarelativistic heavy ion collisions, which is crucial for understanding the early evolution of the system.

  9. Jet Reconstruction with Particle Flow in Heavy-Ion Collisions with CMS

    E-Print Network [OSTI]

    Matthew Nguyen; for the CMS collaboration

    2011-07-27T23:59:59.000Z

    In the particle-flow approach information from all available sub-detector systems is combined to reconstruct all stable particles. The global event reconstruction has been shown to improve, in particular, the resolution of jet energy and missing transverse energy in pp collisions compared to purely calorimetric measurements. This improvement is achieved primarily by combining the precise momentum determination of charged hadrons in the silicon tracker with the associated energy depositions in the calorimeters. By resolving individual particles inside jets, particle flow reduces the sensitivity of the jet energy scale to the jet fragmentation pattern, which is known to be one of the largest sources of systematic uncertainty in jet reconstruction. Particle flow reconstruction is thus potentially well-suited for the study of potential modifications to jet fragmentation in heavy-ion collisions. The particle flow algorithm has been adapted to the heavy-ion environment. The performance of jet reconstruction from particle flow objects in PbPb collisions using the anti-kT jet reconstruction algorithm is presented.

  10. Charged Particle and Photon Multiplicity, and Transverse Energy Production in High-Energy Heavy-Ion Collisions

    E-Print Network [OSTI]

    Sahoo, Raghunath; Behera, Nirbhay K; Nandi, Basanta K

    2014-01-01T23:59:59.000Z

    We review the charged particle and photon multiplicity, and transverse energy production in heavy-ion collisions starting from few GeV to TeV energies. The experimental results of pseudorapidity distribution of charged particles and photons at different collision energies and centralities are discussed. We also discuss the hypothesis of limiting fragmentation and expansion dynamics using the Landau hydrodynamics and the underlying physics. Meanwhile, we present the estimation of initial energy density multiplied with formation time as a function of different collision energies and centralities. In the end, the transverse energy per charged particle in connection with the chemical freeze-out criteria is discussed. We invoke various models and phenomenological arguments to interpret and characterize the fireball created in heavy-ion collisions. This review overall provides a scope to understand the heavy-ion collision data and a possible formation of a deconfined phase of partons via the global observables like...

  11. Stress influenced trapping processes in Si based multi-quantum well structures and heavy ions implanted Si

    SciTech Connect (OSTI)

    Ciurea, Magdalena Lidia, E-mail: ciurea@infim.ro; Lazanu, Sorina, E-mail: ciurea@infim.ro [National Institute for Materials Physics, 105bis Atomistilor Street, 077125 Magurele (Romania)

    2014-10-06T23:59:59.000Z

    Multi-quantum well structures and Si wafers implanted with heavy iodine and bismuth ions are studied in order to evaluate the influence of stress on the parameters of trapping centers. The experimental method of thermostimullatedcurrents without applied bias is used, and the trapping centers are filled by illumination. By modeling the discharge curves, we found in multilayered structures the parameters of both 'normal' traps and 'stress-induced' ones, the last having a Gaussian-shaped temperature dependence of the cross section. The stress field due to the presence of stopped heavy ions implanted into Si was modeled by a permanent electric field. The increase of the strain from the neighborhood of I ions to the neighborhood of Bi ions produces the broadening of some energy levels and also a temperature dependence of the cross sections for all levels.

  12. Swift-heavy-ion-induced damage formation in III-V binary and ternary semiconductors

    SciTech Connect (OSTI)

    Schnohr, C. S.; Kluth, P.; Giulian, R.; Llewellyn, D. J.; Byrne, A. P.; Cookson, D. J.; Ridgway, M. C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Department of Nuclear Physics, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Australian Synchrotron, Clayton, Victoria 3168 (Australia); Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia)

    2010-02-15T23:59:59.000Z

    Damage formation in InP, GaP, InAs, GaAs, and the related ternary alloys Ga{sub 0.50}In{sub 0.50}P and Ga{sub 0.47}In{sub 0.53}As irradiated at room temperature with 185 MeV Au ions was studied using Rutherford backscattering spectroscopy in channeling configuration, transmission electron microscopy, and small-angle x-ray scattering. Despite nearly identical ion-energy loss in these materials, their behavior under swift-heavy-ion irradiation is strikingly different: InP and Ga{sub 0.50}In{sub 0.50}P are readily amorphized, GaP and GaAs remain almost undamaged and InAs and Ga{sub 0.47}In{sub 0.53}As exhibit intermediate behavior. A material-dependent combination of irradiation-induced damage formation and annealing is proposed to describe the different responses of the III-V materials to electronic energy loss.

  13. Radiation damage by light- and heavy-ion bombardment of single-crystal LiNbO?

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

    Huang, Hsu-Cheng; Zhang, Lihua; Malladi, Girish; Dadap, Jerry I.; Manandhar, Sandeep; Kisslinger, Kim; Vemuri, Rama Sesha R.; Shutthanandan, Vaithiyalingam; Bakhru, Hassaram; Osgood, Jr., Richard M.

    2015-01-01T23:59:59.000Z

    In this work, a battery of analytical methods including in situ RBS/C, confocal micro-Raman, TEM/STEM, EDS, AFM, and optical microscopy were used to provide a comparative investigation of light- and heavy-ion radiation damage in single-crystal LiNbO?. High (~MeV) and low (~100s keV) ion energies, corresponding to different stopping power mechanisms, were used and their associated damage events were observed. In addition, sequential irradiation of both ion species was also performed and their cumulative depth-dependent damage was determined. It was found that the contribution from electronic stopping by high-energy heavy ions gave rise to a lower critical fluence for damage formationmore »than for the case of low-energy irradiation. Such energy-dependent critical fluence of heavy-ion irradiation is two to three orders of magnitude smaller than that for the case of light-ion damage. In addition, materials amorphization and collision cascades were seen for heavy-ion irradiation, while for light ion, crystallinity remained at the highest fluence used in the experiment. The irradiation-induced damage is characterized by the formation of defect clusters, elastic strain, surface deformation, as well as change in elemental composition. In particular, the presence of nanometric-scale damage pockets results in increased RBS/C backscattered signal and the appearance of normally forbidden Raman phonon modes. The location of the highest density of damage is in good agreement with SRIM calculations. (author)« less

  14. What we have (not)learned from the ultrarelativistic heavy ion collisions

    SciTech Connect (OSTI)

    Paic, Guy [Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Apartado Postal 70-543, Mexico Distrito Federal 04510 (Mexico)

    2009-04-20T23:59:59.000Z

    The field of ultrarelativistic heavy ion collisions is today a flourishing activity both on the experimental and on the theoretical side. Although the theoretical justifications to study these collisions was given already more than three decades ago and the experimental studies have a history of more than 25 years we are still very much in the dark as to the details of the processes and of the characteristics of the matter created in collisions. Increasing the energy of collisions has brought new insights but has also resulted with new challenges. In the present paper I will try from a personal perspective to report on the answers we have collected and on the problems we are faced with. The account is partial, taking into account that it is impossible to render justice to every aspect of the field.

  15. Dynamical approach to heavy-ion induced fusion using actinide target

    SciTech Connect (OSTI)

    Aritomo, Y.; Hagino, K.; Chiba, S.; Nishio, K. [Flerov Laboratory of Nuclear Reactions, JINR, Dubna, 141980 (Russian Federation); Department of Physics, Tohoku University, Sendai 980-8578 (Japan); Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, Tokyo 152-8550 (Japan); Japan Atomic Energy Agency, Tokai, Ibaraki, 319-1195 (Japan)

    2012-10-20T23:59:59.000Z

    To treat heavy-ion reactions using actinide target nucleus, we propose a model which takes into account the coupling to the collective states of interacting nuclei in the penetration of the Coulomb barrier and the dynamical evolution of nuclear shape from the contact configuration. A fluctuation-dissipation model (Langevin equation) was applied in the dynamical calculation, where effect of nuclear orientation at the initial impact on the prolately deformed target nucleus was considered. Using this model, we analyzed the experimental data for the mass distribution of fission fragments (MDFF) in the reaction of {sup 36}S+{sup 238}U at several incident energies. Fusion-fission, quasifission and deep-quasi-fission are separated as different trajectories on the potential energy surface. We estimated the fusion cross section of the reaction.

  16. Interplay of the emission from thermal and direct sources in relativistic heavy ion collisions

    SciTech Connect (OSTI)

    Bozek, Piotr [H. Niewodniczanski Institute of Nuclear Physics, PL-31342 Krakow (Poland); Institute of Physics, Rzeszow University, PL-35959 Rzeszow (Poland)

    2009-05-15T23:59:59.000Z

    The separation of the source created in ultrarelativistic heavy ion collisions into a thermalized dense core and an outer mantle consisting of independent nucleon-nucleon collisions is discussed. Indications for such a two-component picture are found in the transverse mass spectra of kaons, protons, and antiprotons produced in Au-Au collisions at {radical}(s)=200 GeV. Estimates of the sizes of the thermal and direct sources are compared with models separating the interaction zone into a core and a corona. New initial conditions corresponding to the dense core lead to a stronger azimuthal asymmetry of the fireball, and pressure gradients also increase. We find faster transverse hydrodynamic expansion and stronger elliptic flow for the dense core initial conditions.

  17. Dipolar degrees of freedom and Isospin equilibration processes in Heavy Ion collisions

    E-Print Network [OSTI]

    Papa, M; Acosta, L; Amorini, F; Agodi, C; Anzalone, A; Auditore, L; Cardella, G; Cavallaro, S; Chatterjee, M B; De Filippo, E; Francalanza, L; Geraci, E; Grassi, L; Gnoffo, B; Han, J; La Guidara, E; Lanzalone, G; Lombardo, I; Pagano, C Maiolino T Minniti A; Pagano, E V; Pirrone, S; Politi, G; Porto, F; Quattrocchi, L; Rizzo, F; Rosato, E; Russotto, P; Trifirò, A; Trimarchi, M; Verde, G; Vigilante, and M

    2015-01-01T23:59:59.000Z

    Background: In heavy ion collision at the Fermi energies Isospin equilibration processes occur- ring when nuclei with different charge/mass asymmetries interacts have been investigated to get information on the nucleon-nucleon Iso-vectorial effective interaction. Purpose: In this paper, for the system 48Ca +27 Al at 40 MeV/nucleon, we investigate on this process by means of an observable tightly linked to isospin equilibration processes and sensitive in exclusive way to the dynamical stage of the collision. From the comparison with dynamical model calculations we want also to obtain information on the Iso-vectorial effective microscopic interaction. Method: The average time derivative of the total dipole associated to the relative motion of all emitted charged particles and fragments has been determined from the measured charges and velocities by using the 4? multi-detector CHIMERA. The average has been determined for semi- peripheral collisions and for different charges Zb of the biggest produced fragment. E...

  18. Excitation of nuclear anharmonic vibrations in heavy-ion fusion reactions

    E-Print Network [OSTI]

    K. Hagino; S. Kuyucak; N. Takigawa

    1997-11-05T23:59:59.000Z

    We discuss the effects of multi-phonon excitations on heavy-ion fusion reactions at energies near and below the Coulomb barrier, focusing especially on the role of anharmonicities. We carry out a systematic study of those effects on the excitation function of the fusion cross section and on the fusion barrier distribution, by using the vibrational limit of the interacting boson model. We also analyze the recently measured high-precision data of the $^{16}$O + $^{148}$Sm fusion reaction with this model and discuss the anharmonic properties of the quadrupole as well as the octupole vibrations in $^{148}$Sm. Negative and positive static quadrupole moments are deduced for the first 2$^+$ and 3$^-$ states in $^{148}$Sm, respectively. It is shown that the fusion barrier distribution strongly depends on the sign of the quadrupole moments, suggesting that subbarrier fusion reactions offer an alternative method to extract the static quadrupole moments of phonon states in spherical nuclei.

  19. Ion assisted deposition of optical and protective coatings for heavy metal fluoride glass

    SciTech Connect (OSTI)

    McNally, J.J.; Al-Jumaily, G.A.; McNeil, J.R.

    1986-06-15T23:59:59.000Z

    Heavy metal fluoride glass materials are attractive for optical applications in the near UV through IR wavelength regions. However, many compositions are relatively soft and hygroscopic and possess low softening temperature (250--300/sup 0/C). We have applied ion assisted deposition (IAD) techniques to deposit MgF/sub 2/, SiO/sub 2/, and Al/sub 2/O/sub 3//SiO/sub 2/ thin film structures on fluoride glass substrates at ambient substrate temperature (--100/sup 0/C). The coatings deposited using IAD improve the environmental durability of the fluoride glass and appear to have reasonably good optical characteristics; without application of IAD, the deposited coatings are not durable and have poor adhesion.

  20. Scaling of Anisotropic Flows in Intermediate Energy and Ultra-relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Y. G. Ma

    2006-11-30T23:59:59.000Z

    Anisotropic flows ($v_2$ and $v_4$) of hadrons and light nuclear clusters are studied by a partonic transport model and nucleonic transport model, respectively, in ultra-relativistic and intermediate energy heavy ion collisions. Both number-of-constituent-quark scaling of hadrons, especially for $\\phi$ meson which is composed of strange quarks, and number-of-nucleon scaling of light nuclear clusters are discussed and explored for the elliptic flow ($v_2$). The ratios of $v_4/v_2^2$ of hadrons and nuclear clusters are, respectively, calculated and they show different constant values which are independent of transverse momentum. The above phenomena can be understood, respectively, by the coalescence mechanism in quark-level or nucleon-level.

  1. Heavy Ion Beam in Resolution of the Critical Point Problem for Uranium and Uranium Dioxide

    E-Print Network [OSTI]

    Igor Iosilevskiy; Victor Gryaznov

    2010-05-23T23:59:59.000Z

    Important advantages of heavy ion beam (HIB) irradiation of matter are discussed in comparison with traditional sources - laser heating, electron beam, electrical discharge etc. High penetration length (~ 10 mm) is of primary importance for investigation of dense matter properties. This gives an extraordinary chance to reach the uniform heating regime when HIB irradiation is being used for thermophysical property measurements. Advantages of HIB heating of highly-dispersive samples are claimed for providing free and relatively slow quasi-isobaric heating without fast hydrodynamic expansion of heated sample. Perspective of such HIB application are revised for resolution of long-time thermophysical problems for uranium and uranium-bearing compounds (UO2). The priorities in such HIB development are stressed: preferable energy levels, beam-time duration, beam focusing, deposition of the sample etc.

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

    E-Print Network [OSTI]

    McLerran, Larry

    2015-01-01T23:59:59.000Z

    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.

  3. Swift heavy ion irradiation of Pt nanocrystals: II. Structural changes and H desorption

    SciTech Connect (OSTI)

    Giulian, R.; Araujo, L.L.; Kluth, P.; Sprouster, D.J.; Schnohr, C.S.; Byrne, A.P.; Ridgway, M.C. (ANU)

    2014-09-24T23:59:59.000Z

    The structural properties and H desorption from embedded Pt nanocrystals (NCs) following irradiation with swift heavy ions were investigated as a function of energy and fluence. From x-ray absorption near-edge spectroscopy analysis, Pt-H bonding was identified in NCs annealed in a forming gas (95% N{sub 2} + 5% H{sub 2}) ambient. The H content decreased upon irradiation and the desorption process was NC-size dependent such that larger NCs required a higher fluence to achieve a H-free state. Pt-H bonding and NC dissolution both perturbed the NC structural parameters (coordination number, bond-length and mean-square relative displacement) as determined with extended x-ray absorption fine structure measurements.

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

    E-Print Network [OSTI]

    Thomas J. Humanic

    2005-10-17T23:59:59.000Z

    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.

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

    SciTech Connect (OSTI)

    Greco, V. [Department of Physics and Astronomy, University of Catania, Catania, Italy and INFN - Laboratori Nazionali del Sud, Catania (Italy)

    2014-05-09T23:59:59.000Z

    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)

  6. Heavy ion beam probe advances from the first installation of the diagnostic on an RFP (invited)

    SciTech Connect (OSTI)

    Demers, D. R.; Fimognari, P. J. [Xantho Technologies, LLC, Madison, Wisconsin 53705 (United States)

    2012-10-15T23:59:59.000Z

    Heavy ion beam probes have been installed on a variety of toroidal devices, but the first and only application on a reversed field pinch is the diagnostic on the Madison Symmetric Torus. Simultaneous measurements of spatially localized equilibrium potential and fluctuations of density and potential, previously inaccessible in the core of the reversed field pinch (RFP), are now attainable. These measurements reflect the unique strength of the heavy ion beam probe (HIBP) diagnostic. They will help determine the characteristics and evolution of electrostatic fluctuations and their role in transport, and determine the relation of the interior electric field and flows. Many aspects of the RFP present original challenges to HIBP operation and inference of plasma quantities. The magnetic field contributes to a number of the issues: the comparable magnitudes of the toroidal and poloidal fields and edge reversal result in highly three-dimensional beam trajectories; partial generation of the magnetic field by plasma current cause it and hence the beam trajectories to vary with time; and temporal topology and amplitude changes are common. Associated complications include strong ultraviolet radiation and elevated particle losses that can alter functionality of the electrostatic systems and generate noise on the detectors. These complexities have necessitated the development of new operation and data analysis techniques: the implementation of primary and secondary beamlines, adoption of alternative beam steering methods, development of higher precision electrostatic system models, refinement of trajectory calculations and sample volume modeling, establishment of stray particle and noise reduction methods, and formulation of alternative data analysis techniques. These innovative methods and the knowledge gained with this system are likely to translate to future HIBP operation on large scale stellarators and tokamaks.

  7. Validity of the linear coupling approximation in heavy-ion fusion reactions at sub barrier energies

    E-Print Network [OSTI]

    K. Hagino; N. Takigawa; M. Dasgupta; D. J. Hinde; J. R. Leigh

    1996-07-26T23:59:59.000Z

    The role of higher order coupling of surface vibrations to the relative motion in heavy-ion fusion reactions at near-barrier energies is investigated. The coupled channels equations are solved to all orders, and also in the linear and the quadratic coupling approximations. Taking $^{64}$Ni + $^{92,96}$Zr reactions as examples, it is shown that all order couplings lead to considerably improved agreement with the experimentally measured fusion cross sections and average angular momenta of the compound nucleus for such heavy nearly symmetric systems. The importance of higher order coupling is also examined for asymmetric systems like $^{16}$O + $^{112}$Cd, $^{144}$Sm, for which previous calculations of the fusion cross section seemed to indicate that the linear coupling approximation was adequate. It is shown that the shape of the barrier distributions and the energy dependence of the average angular momentum can change significantly when the higher order couplings are included, even for systems where measured fusion cross sections may seem to be well reproduced by the linear coupling approximation.

  8. Future directions in intermediate energy heavy ion physics. A proposed expansion of the Holifield Facility

    SciTech Connect (OSTI)

    Not Available

    1986-02-01T23:59:59.000Z

    A proposal is presented for a major accelerator addition to the Holifield Heavy Ion Research Facility. The expanded facility will provide ion beams of mass 1 to 238 amu with a combination of energy, intensity, momentum resolution, and beam quality not currently available at any other facility in North America. The physics motivation for such an addition is discussed, and involves physics dominated by meson-exchange forces, Coulomb-force dominated physics, and possibly a regime where the quark and gluon degrees of freedom are significant. The physics research would include topics in atomic and interdisciplinary areas as well as nuclear physics. Some remarks are made on the merits of Oak Ridge as a site for this facility, placing the proposal in some historical perspective. The accelerator system is then described, giving the required beam properties, and the parameters of the synchrotron ring components, injection, ring magnets, RF systems, vacuum system, and electron cooling system and stochastic cooling system requirements. Also described are such facilities as buildings, beam transport and shielding, and experimental facilities, including target areas. (LEW)

  9. Response of sensitive human ataxia and resistant T-1 cell lines to accelerated heavy ions

    SciTech Connect (OSTI)

    Tobias, C.A.; Blakely, E.A.; Chang, P.Y.; Lommel, L.; Roots, R.

    1983-07-01T23:59:59.000Z

    The radiation dose responses of fibroblast from a patient with Ataxia telangiectasis (AT-2SF) and an established line of human T-1 cells were studied. Nearly monoenergetic accelerated neon and argon ions were used at the Berkeley Bevalac with various residual range values. The LET of the particles varied from 30 keV/..mu..m to over 1000 keV/..mu..m. All Ataxia survival curves were exponential functions of the dose. Their radiosensitivity reached peak values at 100 to 200 keV/..mu..m. Human T-1 cells have effective sublethal damage repair as has been evidenced by split dose experiments, and they are much more resistant to low LET than to high LET radiation. The repair-misrepair model has been used to interpret these results. We have obtained mathematical expressions that describe the cross sections and inactivation coefficients for both human cell lines as a function of the LET and the type of particle used. The results suggest either that high-LET particles induce a greater number of radiolesions per track or that heavy-ions at high LET induce lesions that kill cells more effectively and that are different from those produced at low LET. We assume that the lesions induced in T-1 and Ataxia cells are qualitatively similar and that each cell line attempts to repair these lesions. The result in most irradiated Ataxia cells, however, is either lethal misrepair or incomplete repair leading to cell death. 63 references, 10 figures, 1 table.

  10. Muon Muon Collider: Feasibility Study

    SciTech Connect (OSTI)

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

    2012-04-05T23:59:59.000Z

    A feasibility study is presented of a 2 + 2 TeV muon collider with a luminosity of L = 10{sup 35} cm{sup -2}s{sup -1}. The resulting design is not optimized for performance, and certainly not for cost; however, it does suffice - we believe - to allow us to make a credible case, that a muon collider is a serious possibility for particle physics and, therefore, worthy of R and D support so that the reality of, and interest in, a muon collider can be better assayed. The goal of this support would be to completely assess the physics potential and to evaluate the cost and development of the necessary technology. The muon collider complex consists of components which first produce copious pions, then capture the pions and the resulting muons from their decay; this is followed by an ionization cooling channel to reduce the longitudinal and transverse emittance of the muon beam. The next stage is to accelerate the muons and, finally, inject them into a collider ring wich has a small beta function at the colliding point. This is the first attempt at a point design and it will require further study and optimization. Experimental work will be needed to verify the validity of diverse crucial elements in the design. Muons because of their large mass compared to an electron, do not produce significant synchrotron radiation. As a result there is negligible beamstrahlung and high energy collisions are not limited by this phenomena. In addition, muons can be accelerated in circular devices which will be considerably smaller than two full-energy linacs as required in an e{sup +} - e{sup -} collider. A hadron collider would require a CM energy 5 to 10 times higher than 4 TeV to have an equivalent energy reach. Since the accelerator size is limited by the strength of bending magnets, the hadron collider for the same physics reach would have to be much larger than the muon collider. In addition, muon collisions should be cleaner than hadron collisions. There are many detailed particle reactions which are open to a muon collider and the physics of such reactions - what one learns and the necessary luminosity to see interesting events - are described in detail. Most of the physics accesible to an e{sup +} - e{sup -} collider could be studied in a muon collider. In addition the production of Higgs bosons in the s-channel will allow the measurement of Higgs masses and total widths to high precision; likewise, t{bar t} and W{sup +}W{sup -} threshold studies would yield m{sub t} and m{sub w} to great accuracy. These reactions are at low center of mass energy (if the MSSM is correct) and the luminosity and {Delta}p/p of the beams required for these measurements is detailed in the Physics Chapter. On the other hand, at 2 + 2 TeV, a luminosity of L {approx} 10{sup 35} cm{sup -2}s{sup -1} is desirable for studies such as, the scattering of longitudinal W bosons or the production of heavy scalar particles. Not explored in this work, but worth noting, are the opportunities for muon-proton and muon-heavy ion collisions as well as the enormous richness of such a facility for fixed target physics provided by the intense beams of neutrinos, muons, pions, kaons, antiprotons and spallation neutrons. To see all the interesting physics described herein requires a careful study of the operation of a detector in the very large background. Three sources of background have been identified. The first is from any halo accompanying the muon beams in the collider ring. Very carefully prepared beams will have to be injected and maintained. The second is due to the fact that on average 35% of the muon energy appears in its decay electron. The energy of the electron subsequently is converted into EM showers either from the synchrotron radiation they emit in the collider magnetic field or from direct collision with the surrounding material. The decays that occur as the beams traverse the low beta insert are of particular concern for detector backgrounds. A third source of background is e{sup +} - e{sup -} pair creation from {mu}{sup +} - {mu}{sup -} interaction. Studies of

  11. INACTIVATION OF HUMAN KIDNEY CELLS BY HIGH-ENERGY MONOENERGETIC HEAVY-ION BEAMS

    E-Print Network [OSTI]

    Blakely, E.A.

    2011-01-01T23:59:59.000Z

    measured in the second ion chamber to that measuredin the monitor ion chamber.collector of the second ion chamber (l-cm diameter) is used

  12. Quarkonia Disintegration due to time dependence of the $q \\bar{q}$ potential in Relativistic Heavy Ion Collisions

    E-Print Network [OSTI]

    Partha Bagchi; Ajit M. Srivastava

    2014-11-20T23:59:59.000Z

    Rapid thermalization in ultra-relativistic heavy-ion collisions leads to fast changing potential between a heavy quark and antiquark from zero temperature potential to the finite temperature one. Time dependent perturbation theory can then be used to calculate the survival probability of the initial quarkonium state. In view of very short time scales of thermalization at RHIC and LHC energies, we calculate the survival probability of $J/\\psi$ and $\\Upsilon$ using sudden approximation. Our results show that quarkonium decay may be significant even when temperature of QGP remains low enough so that the conventional quarkonium melting due to Debye screening is ineffective.

  13. Subbarrier heavy ion fusion enhanced by nucleon transfer and subbarrier fusion of nuclei far from the line of ?-stability

    E-Print Network [OSTI]

    V. Yu. Denisov

    1998-09-28T23:59:59.000Z

    We discuss a model for the description of subbarrier fusion of heavy ions which takes into account the coupling to the low-energy surface vibrational states and to the few-nucleon transfer with arbitrary reaction Q-value. The fusion reactions ^{28,30}Si+^{58,62,64}Ni, ^{40}Ca+^{90,96}Zr, ^{28}S+^{94,100}Mo, ^{16,18,20,22,24}O+^{58}Ni and ^{28}Si+^{124,126,128,130,132}Sn are analyzed in detail. The model describes rather well the experimental fusion cross section and mean angular momentum for reactions between nuclei near the \\beta-stability line. It is shown that these quantities are significantly enhanced by few-nucleon transfer with large positive Q-value. A shape independent parameterization of the heavy ion potential at distances smaller then the touching point is proposed.

  14. Charge splitting of directed flow and charge-dependent effects in pion spectra in heavy ion collisions

    E-Print Network [OSTI]

    A. Rybicki; A. Szczurek; M. Klusek-Gawenda; M. Kielbowicz

    2015-02-12T23:59:59.000Z

    The large and rapidly varying electric and magnetic fields induced by the spectator systems moving at ultrarelativistic velocities induce a charge splitting of directed flow, $v_1$, of positive and negative pions in the final state of the heavy ion collision. The same effect results in a very sizeable distortion of charged pion spectra as well as ratios of charged pions ($\\pi^+/\\pi^-$) emitted at high values of rapidity. Both phenomena are sensitive to the actual distance between the pion emission site and the spectator system. This distance $d_E$ appears to decrease with increasing rapidity of the pion, and comes below $\\sim$1~fm for pions emitted close to beam rapidity. In this paper we discuss how these findings can shed new light on the space-time evolution of pion production as a function of rapidity, and on the longitudinal evolution of the system created in heavy ion collisions.

  15. Elliptic flow fluctuations in heavy ion collisions at RHIC and the perfect fluid hypothesis

    E-Print Network [OSTI]

    Sascha Vogel; Giorgio Torrieri; Marcus Bleicher

    2010-08-05T23:59:59.000Z

    We analyse the recently measured $v_2$ fluctuation in the context of establishing the degree of fluidity of the matter produced in heavy ion collisions. We argue that flow observables within systems with a non-negligible mean free path should acquire a "dynamical" fluctuation, due to the random nature of each collision between the system's degrees of freedom. Because of this, $v_2$ fluctuations can be used to estimate the Knudsen number of the system produced at RHIC. To illustrate this quantitatively, we apply the UrQMD model, with scaled cross sections, to show that collisions at RHIC have a Knudsen number at least one order of magnitude above the expected value for an interacting hadron gas. Furthermore, we argue that the Knudsen number is also bound from above by the $v_2$ fluctuation data, because too large a Knudsen number would break the observed scaling of $v_2$ fluctuations due to the onset of turbulent flow. We propose, therefore that $v_2$ fluctuation measurements, together with an understanding of the turbulent regime for relativistic hydrodynamics, will provide an upper as well as a lower limit for the Knudsen number.

  16. Constraining supernova equations of state with equilibrium constants from heavy-ion collisions

    E-Print Network [OSTI]

    Matthias Hempel; Kris Hagel; Joseph Natowitz; Gerd Röpke; Stefan Typel

    2015-03-02T23:59:59.000Z

    Cluster formation is a fundamental aspect of the equation of state (EOS) of warm and dense nuclear matter such as can be found in supernovae (SN). Similar matter can be studied in heavy-ion collisions (HIC). We use the experimental data of Qin et al. 2012 to test calculations of cluster formation and the role of in-medium modifications of cluster properties in SN EOSs. For the comparison between theory and experiment we use chemical equilibrium constants as the main observables. This reduces some of the systematic uncertainties and allows deviations from ideal gas behavior to be identified clearly. In the analysis, we carefully account for the differences between matter in SN and HIC. We find that, at the lowest densities, the experiment and all theoretical models are consistent with the ideal gas behavior. At higher densities ideal behavior is clearly ruled out and interaction effects have to be considered. The contributions of continuum correlations are of relevance in the virial expansion and remain a difficult problem to solve at higher densities. We conclude that at the densities and temperatures discussed mean-field interactions of nucleons, inclusion of all relevant light clusters, and a suppression mechanism of clusters at high densities have to be incorporated in the SN EOS.

  17. Simulation of neutron displacement damage in bipolar junction transistors using high-energy heavy ion beams.

    SciTech Connect (OSTI)

    Doyle, Barney Lee; Buller, Daniel L.; Hjalmarson, Harold Paul; Fleming, Robert M; Bielejec, Edward Salvador; Vizkelethy, Gyorgy

    2006-12-01T23:59:59.000Z

    Electronic components such as bipolar junction transistors (BJTs) are damaged when they are exposed to radiation and, as a result, their performance can significantly degrade. In certain environments the radiation consists of short, high flux pulses of neutrons. Electronics components have traditionally been tested against short neutron pulses in pulsed nuclear reactors. These reactors are becoming less and less available; many of them were shut down permanently in the past few years. Therefore, new methods using radiation sources other than pulsed nuclear reactors needed to be developed. Neutrons affect semiconductors such as Si by causing atomic displacements of Si atoms. The recoiled Si atom creates a collision cascade which leads to displacements in Si. Since heavy ions create similar cascades in Si we can use them to create similar damage to what neutrons create. This LDRD successfully developed a new technique using easily available particle accelerators to provide an alternative to pulsed nuclear reactors to study the displacement damage and subsequent transient annealing that occurs in various transistor devices and potentially qualify them against radiation effects caused by pulsed neutrons.

  18. SOLAR WIND HEAVY IONS OVER SOLAR CYCLE 23: ACE/SWICS MEASUREMENTS

    SciTech Connect (OSTI)

    Lepri, S. T.; Landi, E.; Zurbuchen, T. H. [Department of Atmospheric, Oceanic, and Space Sciences, University of Michigan, TC 2210 Ann Arbor, MI 48109 (United States)

    2013-05-01T23:59:59.000Z

    Solar wind plasma and compositional properties reflect the physical properties of the corona and its evolution over time. Studies comparing the previous solar minimum with the most recent, unusual solar minimum indicate that significant environmental changes are occurring globally on the Sun. For example, the magnetic field decreased 30% between the last two solar minima, and the ionic charge states of O have been reported to change toward lower values in the fast wind. In this work, we systematically and comprehensively analyze the compositional changes of the solar wind during cycle 23 from 2000 to 2010 while the Sun moved from solar maximum to solar minimum. We find a systematic change of C, O, Si, and Fe ionic charge states toward lower ionization distributions. We also discuss long-term changes in elemental abundances and show that there is a {approx}50% decrease of heavy ion abundances (He, C, O, Si, and Fe) relative to H as the Sun went from solar maximum to solar minimum. During this time, the relative abundances in the slow wind remain organized by their first ionization potential. We discuss these results and their implications for models of the evolution of the solar atmosphere, and for the identification of the fast and slow wind themselves.

  19. Pseudo-Critical Enhancement of Thermal Photons in Relativistic Heavy-Ion Collisions

    E-Print Network [OSTI]

    Hendrik van Hees; Min He; Ralf Rapp

    2014-09-11T23:59:59.000Z

    We compute the spectra and elliptic flow of thermal photons emitted in ultrarelativistic heavy-ion collisions (URHICs) at RHIC and LHC. The thermal emission rates are taken from complete leading-order rates for the QGP and hadronic many-body calculations including baryons and antibaryons, as well as meson-exchange reactions (including Bremsstrahlung). We first update previous thermal fireball calculations by implementing a lattice-QCD based equation of state and extend them to compare to recent LHC data. We then scrutinize the space-time evolution of Au-Au collisions at RHIC by employing an ideal hydrodynamic model constrained by bulk- and multistrange-hadron spectra and elliptic flow, including a non-vanishing initial flow. We systematically compare the evolutions of temperature, radial flow, azimuthal anisotropy and four-volume, and exhibit the temperature profile of thermal photon radiation. Based on these insights, we put forward a scenario with a "pseudo-critical enhancement" of thermal emission rates, and investigate its impact on RHIC and LHC direct photon data.

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

    SciTech Connect (OSTI)

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

    2010-07-07T23:59:59.000Z

    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.

  1. Adiabatic Heavy Ion Fusion Potentials for Fusion at Deep Sub-barrier Energies

    E-Print Network [OSTI]

    S. V. S. Sastry; S. Kailas; A. K. Mohanty; A. Saxena

    2003-11-12T23:59:59.000Z

    The fusion cross sections from well above barrier to extreme sub-barrier energies have been analysed using the energy (E) and angular momentum (L) dependent barrier penetration model ({\\small{ELDBPM}}). From this analysis, the adiabatic limits of fusion barriers have been determined for a wide range of heavy ion systems. The empirical prescription of Wilzynska and Wilzynski has been used with modified radius parameter and surface tension coefficient values consistent with the parameterization of the nuclear masses. The adiabatic fusion barriers calculated from this prescription are in good agreement with the adiabatic barriers deduced from {\\small{ELDBPM}} fits to fusion data. The nuclear potential diffuseness is larger at adiabatic limit, resulting in a lower $\\hbar\\omega$ leading to increase of "logarithmic slope" observed at energies well below the barrier. The effective fusion barrier radius and curvature values are anomalously smaller than the predictions of known empirical prescriptions. A detailed comparison of the systematics of fusion barrier with and without L-dependence has been presented.

  2. 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

    2015-01-14T23:59:59.000Z

    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.

  3. Interplay of the emission from thermal and direct sources in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Piotr Bozek

    2008-11-12T23:59:59.000Z

    The separation of the source created in ultrarelativistic heavy-ion collisions into a thermalized dense core and an outer mantle consisting of independent nucleon-nucleon collisions is discussed. Evidence for such a two component picture is found in transverse mass spectra of kaon, protons and antiprotons produced in Au-Au collisions at 200GeV. Estimates of the sizes of the thermal and direct sources are compared to models separating the interaction zone into a core and a corona, according to the density of participants or to the number of collisions. Consequences for the modeling of the dynamics of the small size, thermalized core are described. New initial conditions corresponding to the dense core lead to a stronger azimuthal asymmetry of the hydrodynamically expanding fireball, pressure gradients also increase. 2+1-dimensional hydrodynamic simulations are presented starting from all the matter in the interaction region or from the dense, thermal part of the source. We find faster transverse expansion and stronger elliptic flow for dense core initial conditions. For different impact parameters we find very similar spectra of the thermal part of the source and only adding particles emitted directly from nucleon-nucleon collisions in the corona the experimentally observed softening of the spectra with increasing impact parameter is reproduced. The elliptic flow is stronger for particles emitted from a source separated into a core and a corona.

  4. Dipolar degrees of freedom and Isospin equilibration processes in Heavy Ion collisions

    E-Print Network [OSTI]

    M. Papa; I. Berceanu; L. Acosta; F. Amorini; C. Agodi; A. Anzalone; L. Auditore; G. Cardella; S. Cavallaro; M. B. Chatterjee; E. De Filippo; L. Francalanza; E. Geraci; L. Grassi; B. Gnoffo; J. Han; E. La Guidara; G. Lanzalone; I. Lombardo; C. Maiolino T. Minniti A. Pagano; E. V. Pagano; S. Pirrone; G. Politi; F. Porto; L. Quattrocchi; F. Rizzo; E. Rosato; P. Russotto; A. Trifirò; M. Trimarchi; G. Verde; and M. Vigilante

    2015-01-05T23:59:59.000Z

    Background: In heavy ion collision at the Fermi energies Isospin equilibration processes occur- ring when nuclei with different charge/mass asymmetries interacts have been investigated to get information on the nucleon-nucleon Iso-vectorial effective interaction. Purpose: In this paper, for the system 48Ca +27 Al at 40 MeV/nucleon, we investigate on this process by means of an observable tightly linked to isospin equilibration processes and sensitive in exclusive way to the dynamical stage of the collision. From the comparison with dynamical model calculations we want also to obtain information on the Iso-vectorial effective microscopic interaction. Method: The average time derivative of the total dipole associated to the relative motion of all emitted charged particles and fragments has been determined from the measured charges and velocities by using the 4? multi-detector CHIMERA. The average has been determined for semi- peripheral collisions and for different charges Zb of the biggest produced fragment. Experimental evidences collected for the systems 27Al+48Ca and 27Al+40Ca at 40 MeV/nucleon used to support this novel method of investigation are also discussed.

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

    E-Print Network [OSTI]

    Yu. B. Ivanov

    2013-02-23T23:59:59.000Z

    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.

  6. Interplay Of Mean Field And Individual Nucleon Collisions Effects At Intermediate Energy Heavy Ion Reactions

    SciTech Connect (OSTI)

    Subotic, K.; Jordanov, D.; Durasevic, M.; Dragosavac, D. [VINCA Institute of Nuclear Sciences, P.O. Box 522, 11001 Belgrade (Serbia and Montenegro); Grabez, B. [Institute of Physics, P.O. Box 57, 11080 Belgrade (Serbia and Montenegro)

    2007-04-23T23:59:59.000Z

    In our study of the reaction 20Ne+27Al at energy of 84 A MeV, the track detectors were used to select the target like fragments arising from processes in which the interacting system becomes disintegrated into a large number of constituent nucleons and one massive fragment. Heavy ion reaction studies at bombarding energies of several tens of MeV/nucleon have provided the evidence that most of reaction cross section, in this energy range, is associated with the production of primary projectile like and target like fragment in the first step of the nuclear reaction. The subsequent evolution of the studied reaction systems, has been usually described either using low energy models based on mean field effects (MFE), or high energy models where reaction proceeds by independent collisions (INC) of individual nucleons in the overlap region between target and projectile. The analysis of our results in terms of different MFE and INC models, prescribing consistent timings, has shown that the reaction mechanism may be defined of interplay of the mean field and individual nucleon collisions effects.

  7. Time evolution of gluon coherent state and its von Neumann entropy in heavy-ion collisions

    E-Print Network [OSTI]

    Hideaki Iida; Teiji Kunihiro; Akira Ohnishi; Toru T. Takahashi

    2014-10-27T23:59:59.000Z

    We propose a new prescription for evaluating a von Neumann entropy in the initial stage of high-energy heavy-ion collisions utilizing the time evolution of classical Yang-Mills (CYM) field: The von Neumann entropy is computed for the quantum coherent states constructed so as to give the classical gluon fields as the expectation values. The entropy is to be liberated when the complete decoherence is achieved. As a demonstration, the time evolution of the CYM dynamics is solved with an initial condition which mimics the Glasma state, though in a non-expanding geometry; the Glasma state is characterized by the longitudinal color-electric and -magnetic fields with gluon fields' fluctuations around it. We find that the initial longitudinal fluctuations of the fields play essential roles for the entropy production in two ways: First, the field fluctuations at $t=0$ themselves act as a source of the von Neumann entropy prepared before the time evolution. Second, the initial fluctuations triggers field instabilities, and hence the larger the strength of them, the more the entropy production at later time.

  8. Di-jet measurements in heavy-ion collisions at STAR

    E-Print Network [OSTI]

    Elena Bruna; for the STAR Collaboration

    2010-10-15T23:59:59.000Z

    Jets are produced from hard scatterings in the early stages of heavy-ion collisions. It is expected that these high-$p_T$ partons travel through the hot and dense medium before fragmenting. Therefore they are expected to suffer energy loss in the QGP via gluon radiation and elastic collisions along their path. Measurements of fully reconstructed jets help understand the effect of the energy loss on the jet structure and energy profile. A data-driven characterization of the background in Au+Au is needed in order to compare the results to p+p. The full azimuthal coverage of STAR Time Projection Chamber and Electromagnetic Calorimeter allows measurements of fully reconstructed di-jets, defined by jets that match the online trigger and recoil jets on the away side. A tight selection of the trigger jets allows for a selection of those coming from the surface. Hence, the population of jets on the recoil side is biased towards a maximal energy loss because of the extreme in-medium pathlength. We present measurements of di-jets, exploring their structure and properties in Au+Au and p+p at $\\sqrt s_{NN}=$200 GeV in the STAR experiment.

  9. Bulk viscosity, particle spectra and flow in heavy-ion collisions

    E-Print Network [OSTI]

    Kevin Dusling; Thomas Schaefer

    2012-01-11T23:59:59.000Z

    We study the effects of bulk viscosity on pT spectra and elliptic flow in heavy ion collisions. For this purpose we compute the dissipative correction df to the single particle distribution functions in leading-log QCD, and in several simplified models. We consider, in particular, the relaxation time approximation and a kinetic model for the hadron resonance gas. We implement these distribution functions in a hydrodynamic simulation of Au + Au collisions at RHIC. We find significant corrections due to bulk viscosity in hadron pT spectra and the differential elliptic flow parameter v2(pT). These corrections are dominated by viscous corrections to the distribution function. We find that the relation between df and the bulk viscosity is different in the quark gluon plasma and hadronic phases. Reliable bounds on the bulk viscosity require accurate calculations of df in a hadronic resonance gas. Based on v2 spectra at RHIC we conservatively estimate zeta/s viscosity on the pT integrated v2 are small.

  10. Temperature dependent sound velocity in hydrodynamic equations for relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Mikolaj Chojnacki

    2007-09-11T23:59:59.000Z

    We analyze the effects of different forms of the sound-velocity function cs(T) on the hydrodynamic evolution of matter formed in the central region of relativistic heavy-ion collisions. At high temperatures (above the critical temperature Tc) the sound velocity is calculated from the recent lattice simulations of QCD, while in the low temperature region it is obtained from the hadron gas model. In the intermediate region we use different interpolations characterized by the values of the sound velocity at the local maximum (at T = 0.4 Tc) and local minimum (at T = Tc). In all considered cases the temperature dependent sound velocity functions yield the entropy density, which is consistent with the lattice QCD simulations at high temperature. Our calculations show that the presence of a distinct minimum of the sound velocity leads to a very long (about 20 fm/c) evolution time of the system, which is not compatible with the recent estimates based on the HBT interferometry. Hence, we conclude that the hydrodynamic description is favored in the case where the cross-over phase transition renders the smooth sound velocity function with a possible shallow minimum at Tc.

  11. Constraining supernova equations of state with equilibrium constants from heavy-ion collisions

    E-Print Network [OSTI]

    Hempel, Matthias; Natowitz, Joseph; Röpke, Gerd; Typel, Stefan

    2015-01-01T23:59:59.000Z

    Cluster formation is a fundamental aspect of the equation of state (EOS) of warm and dense nuclear matter such as can be found in supernovae (SN). Similar matter can be studied in heavy-ion collisions (HIC). We use the experimental data of Qin et al. 2012 to test calculations of cluster formation and the role of in-medium modifications of cluster properties in SN EOSs. For the comparison between theory and experiment we use chemical equilibrium constants as the main observables. This reduces some of the systematic uncertainties and allows deviations from ideal gas behavior to be identified clearly. In the analysis, we carefully account for the differences between matter in SN and HIC. We find that, at the lowest densities, the experiment and all theoretical models are consistent with the ideal gas behavior. At higher densities ideal behavior is clearly ruled out and interaction effects have to be considered. The contributions of continuum correlations are of relevance in the virial expansion and remain a diff...

  12. The role of surface energy coefficients and nuclear surface diffuseness in the fusion of heavy-ions

    E-Print Network [OSTI]

    Ishwar Dutt; Rajeev K. Puri

    2010-05-06T23:59:59.000Z

    We discuss the effect of surface energy coefficients as well as nuclear surface diffuseness in the proximity potential and ultimately in the fusion of heavy-ions. Here we employ different versions of surface energy coefficients. Our analysis reveals that these technical parameters can influence the fusion barriers by a significant amount. A best set of these parameters is also given that explains the experimental data nicely.

  13. Ferroelectric plasma sources for NDCX-II and heavy ion drivers E.P. Gilson a,n

    E-Print Network [OSTI]

    Gilson, Erik

    a , P.C. Efthimion a , I.D. Kaganovich a , J.W. Kwan b , S.M. Lidia b , P.A. Ni b , P.K. Roy b , PFerroelectric plasma sources for NDCX-II and heavy ion drivers E.P. Gilson a,n , R.C. Davidson, Princeton University, P.O. Box 451, Princeton, New Jersey, 08543, USA b Lawrence Berkeley National

  14. Hindrance of Heavy-ion Fusion at Extreme Sub-Barrier Energies in Open-shell Colliding Systems

    E-Print Network [OSTI]

    C. L. Jiang; K. E. Rehm; H. Esbensen; R. V. F. Janssens; B. B. Back; P. Collon; C. N. Davids; J. P. Greene; D. J. Henderson; C. J. Lister; S. Kurtz; R. C. Pardo; T. Pennington; M. Paul; D. Peterson; D. Seweryniak; B. Shumard; S. Sinha; X. D. Tang; I. Tanihata; S. Zhu

    2004-12-20T23:59:59.000Z

    The excitation function for the fusion-evaporation reaction 64Ni+100Mo has been measured down to a cross-section of ~5 nb. Extensive coupled-channels calculations have been performed, which cannot reproduce the steep fall-off of the excitation function at extreme sub-barrier energies. Thus, this system exhibits a hindrance for fusion, a phenomenon that has been discovered only recently. In the S-factor representation introduced to quantify the hindrance, a maximum is observed at E_s=120.6 MeV, which corresponds to 90% of the reference energy E_s^ref, a value expected from systematics of closed-shell systems. A systematic analysis of Ni-induced fusion reactions leading to compound nuclei with mass A=100-200 is presented in order to explore a possible dependence of the fusion hindrance on nuclear structure.

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

    SciTech Connect (OSTI)

    Not Available

    1994-11-01T23:59:59.000Z

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

  16. Proceedings of RIKEN BNL Research Center Workshop entitled Hydrodynamics in Heavy Ion Collisions and QCD Equation of State (Volume 88)

    SciTech Connect (OSTI)

    Karsch,F.; Kharzeev, D.; Molnar, K.; Petreczky, P.; Teaney, D.

    2008-04-21T23:59:59.000Z

    The interpretation of relativistic heavy-ion collisions at RHIC energies with thermal concepts is largely based on the relative success of ideal (nondissipative) hydrodynamics. This approach can describe basic observables at RHIC, such as particle spectra and momentum anisotropies, fairly well. On the other hand, recent theoretical efforts indicate that dissipation can play a significant role. Ideally viscous hydrodynamic simulations would extract, if not only the equation of state, but also transport coefficients from RHIC data. There has been a lot of progress with solving relativistic viscous hydrodynamics. There are already large uncertainties in ideal hydrodynamics calculations, e.g., uncertainties associated with initial conditions, freezeout, and the simplified equations of state typically utilized. One of the most sensitive observables to the equation of state is the baryon momentum anisotropy, which is also affected by freezeout assumptions. Up-to-date results from lattice quantum chromodynamics on the transition temperature and equation of state with realistic quark masses are currently available. However, these have not yet been incorporated into the hydrodynamic calculations. Therefore, the RBRC workshop 'Hydrodynamics in Heavy Ion Collisions and QCD Equation of State' aimed at getting a better understanding of the theoretical frameworks for dissipation and near-equilibrium dynamics in heavy-ion collisions. The topics discussed during the workshop included techniques to solve the dynamical equations and examine the role of initial conditions and decoupling, as well as the role of the equation of state and transport coefficients in current simulations.

  17. Cavity morphology in a Ni based superalloy under heavy ion irradiation with hot pre-injected helium. II

    SciTech Connect (OSTI)

    Zhang, He; Yao, Zhongwen, E-mail: yaoz@me.queensu.ca; Daymond, Mark R. [Department of Mechanical and Materials Engineering, Queen's University Kingston, Ontario K7L 3N6 (Canada); Kirk, Marquis A. [Material Science Division, Argonne National Laboratory Argonne, Illinois 60439 (United States)

    2014-03-14T23:59:59.000Z

    In the current investigation, TEM in-situ heavy ion (1?MeV Kr{sup 2+}) irradiation with helium pre-injected at elevated temperature (400?°C) was conducted to simulate in-reactor neutron irradiation induced damage in CANDU spacer material Inconel X-750, in an effort to understand the effects of helium on irradiation induced cavity microstructures. Three different quantities of helium, 400 appm, 1000 appm, and 5000 appm, were pre-injected directly into TEM foils at 400?°C. The samples containing helium were then irradiated in-situ with 1?MeV Kr{sup 2+} at 400?°C to a final dose of 5.4 dpa (displacement per atom). Cavities were formed from the helium injection solely and the cavity density and size increased with increasing helium dosage. In contrast to previous heavy ion irradiations with cold pre-injected helium, heterogeneous nucleation of cavities was observed. During the ensuing heavy ion irradiation, dynamical observation showed noticeable size increase in cavities which nucleated close to the grain boundaries. A “bubble-void” transformation was observed after Kr{sup 2+} irradiation to high dose (5.4?dpa) in samples containing 1000 appm and 5000 appm helium. Cavity distribution was found to be consistent with in-reactor neutron irradiation induced cavity microstructures. This implies that the distribution of helium is greatly dependent on the injection temperature, and helium pre-injection at high temperature is preferred for simulating the migration of the transmutation produced helium.

  18. Charged Particle and Photon Multiplicity, and Transverse Energy Production in High-Energy Heavy-Ion Collisions

    E-Print Network [OSTI]

    Raghunath Sahoo; Aditya Nath Mishra; Nirbhay K. Behera; Basanta K. Nandi

    2014-08-25T23:59:59.000Z

    We review the charged particle and photon multiplicity, and transverse energy production in heavy-ion collisions starting from few GeV to TeV energies. The experimental results of pseudorapidity distribution of charged particles and photons at different collision energies and centralities are discussed. We also discuss the hypothesis of limiting fragmentation and expansion dynamics using the Landau hydrodynamics and the underlying physics. Meanwhile, we present the estimation of initial energy density multiplied with formation time as a function of different collision energies and centralities. In the end, the transverse energy per charged particle in connection with the chemical freeze-out criteria is discussed. We invoke various models and phenomenological arguments to interpret and characterize the fireball created in heavy-ion collisions. This review overall provides a scope to understand the heavy-ion collision data and a possible formation of a deconfined phase of partons via the global observables like charged particles, photons and the transverse energy measurement.

  19. Mini-jet thermalization and diffusion of transverse momentum correlation in high-energy heavy-ion collisions

    E-Print Network [OSTI]

    Long-gang Pang; Qun Wang; Xin-Nian Wang; Rong Xu

    2009-11-13T23:59:59.000Z

    Transverse momentum correlation in azimuthal angle of produced hadrons due to mini-jets are studied first within the HIJING Monte Carlo model in high-energy heavy-ion collisions. Jet quenching in the early stage of thermalization is shown to lead to significant diffusion (broadening) of the correlation. Evolution of the transverse momentum density fluctuation that gives rise to such correlation in azimuthal angle in the later stage of heavy-ion collisions is further investigated within a linearized diffusion-like equation and is shown to be determined by the shear viscosity of the evolving dense matter. Such a diffusion equation for the transverse momentum fluctuation is solved with initial values given by HIJING and together with the hydrodynamic equation for the bulk medium. The final transverse momentum correlation in azimuthal angle is calculated along the freeze-out hyper-surface and is found further diffused for larger values of shear viscosity to entropy density ratio $\\eta/s \\sim 0.2-0.4$. Therefore the final transverse momentum correlation in azimuthal angle can be used to study the thermalization of mini-jets in the early stage of heavy-ion collisions and the viscous effect in the hydrodynamic evolution of the strongly coupled quark gluon plasma.

  20. Heavy flavour production at LHC

    E-Print Network [OSTI]

    Alessandro Grelli; Andre Mischke

    2009-09-25T23:59:59.000Z

    The Large Hadron Collider (LHC) will open a new era in high energy physics. The expected large cross section for heavy flavour production in proton-proton collisions at $\\sqrt{s}$ = 14 TeV will allow detailed studies of the production mechanisms and an extensive test of Quantum Chromodynamics. Since charm and beauty has been proposed as a good probe to study hot and dense QCD matter, the understanding of the production mechanisms in elementary proton-proton collisions is of primary importance as a reference for studies in heavy-ion collisions. In the early phase of LHC operation the experiments will focus on the investigation of the heavy flavour production mechanisms.

  1. JOURNAL DE PHYSIQUE Colloque C5, supplment au n 11, Tome 21, Novembre 1976, page C5-161 DETECTION AND IDENTIFICATION OF HEAVY ION REACTION PRODUCTS

    E-Print Network [OSTI]

    Boyer, Edmond

    produced in a nuclear reaction of two heavy nuclei (A>10). Reaction products are to be detected and identified as fast (g * 15%) energetic residues of the nuclear reaction. The detection time, governed one detection problem in heavy ion reactions, that is fusion. Here we actually know the reaction

  2. Luminosity Tuning at the Large Hadron Collider

    E-Print Network [OSTI]

    Wittmer, W

    2006-01-01T23:59:59.000Z

    By measuring and adjusting the beta-functions at the interaction point (IP the luminosity is being optimized. In LEP (Large Electron Positron Collider) this was done with the two closest doublet magnets. This approach is not applicable for the LHC (Large Hadron Collider) and RHIC (Relativistic Heavy Ion Collider) due to the asymmetric lattice. In addition in the LHC both beams share a common beam pipe through the inner triplet magnets (in these region changes of the magnetic field act on both beams). To control and adjust the beta-functions without perturbation of other optics functions, quadrupole groups situated on both sides further away from the IP have to be used where the two beams are already separated. The quadrupoles are excited in specific linear combinations, forming the so-called "tuning knobs" for the IP beta-functions. For a specific correction one of these knobs is scaled by a common multiplier. The different methods which were used to compute such knobs are discussed: (1) matching in MAD, (2)i...

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

    E-Print Network [OSTI]

    Gurrola, Alfredo

    2011-10-21T23:59:59.000Z

    to energies of the electroweak scale. Extensions to the SM have been developed as a means of explaining experimental observation. If these extensions are indeed the correct mathematical descriptions of nature, the Large Hadron Collider (LHC), located...

  4. Pre-equilibrium evolution effects on heavy-ion collision observables

    E-Print Network [OSTI]

    Jia Liu; Chun Shen; Ulrich W. Heinz

    2015-04-09T23:59:59.000Z

    In order to investigate the importance of pre-equilibrium dynamics on relativistic heavy-ion collision observables, we match a highly non-equilibrium early evolution stage, modeled by free-streaming partons generated from the Monte Carlo Kharzeev-Levin-Nardi (MC-KLN) and Monte Carlo Glauber (MC-Glb) models, to a locally approximately thermalized later evolution stage described by viscous hydrodynamics, and study the dependence of final hadronic transverse momentum distributions, in particular their underlying radial and anisotropic flows, on the switching time between these stages. Performing a 3-parameter fit of the measured values for the average transverse momenta $\\langle p_\\perp \\rangle$ for pions, kaons and protons as well as the elliptic and triangular flows of charged hadrons $v_{2,3}^\\mathrm{ch}$, with the switching time $\\tau_s$, the specific shear viscosity $\\eta/s$ during the hydrodynamic stage, and the kinetic decoupling temperature $T_\\mathrm{dec}$ as free parameters, we find that the preferred "thermalization" times $\\tau_s$ depend strongly on the model of the initial conditions. MC-KLN initial conditions require an earlier transition to hydrodynamic behavior (at $\\tau_s \\approx$ 0.13 fm/$c$) , followed by hydrodynamic evolution with a larger specific shear viscosity $\\eta/s\\approx$ 0.2, than MC-Glb initial conditions which prefer switching at a later time ($\\tau_s\\approx$ 0.6 fm/$c$) followed by a less viscous hydrodynamic evolution with $\\eta/s\\approx$ 0.16. These new results including pre-equilibrium evolution are compared to fits without a pre-equilbrium stage where all dynamic evolution before the onset of hydrodynamic behavior is ignored. In each case, the quality of the dynamical descriptions for the optimized parameter sets, as well as the observables which show the strongest constraining power for the thermalization time, are discussed.

  5. Effects of nuclear absorption on the antiLambda/antiproton ratio in relativistic heavy ion collisions

    E-Print Network [OSTI]

    Fuqiang Wang; Marlene Nahrgang; Marcus Bleicher

    2012-06-30T23:59:59.000Z

    An enhanced antiLambda/antiproton ratio in heavy-ion relative to p+p collisions has been proposed as one of the signatures for the Quark-Gluon Plasma (QGP) formation. A significantly large (antiLambda+antiSigma0+1.1*antiSigma-)/antiproton ratio of 3.5 has been observed in the mid-rapidity and low transverse momentum region in central Au+Au collisions at the nucleon-nucleon center-of-mass energy of 4.9 GeV at the Alternating Gradient Synchrotron (AGS). This is an order of magnitude larger than the values in peripheral Au+Au collisions and p+p collisions at the corresponding energy. By using the Ultra-relativistic Quantum Molecular Dynamics (UrQMD) transport model, we demonstrate that the observed large ratio can be explained by strong absorption of antiprotons (~99.9%) and antiLambdas (~99%) in dense nuclear matter created in central collisions. We find within the model that the initial antiLambda/antiproton ratio, mainly from string fragmentation, does not depend on the collision centrality, and is consistent with that observed in p+p collisions. This suggests that the observed large (antiLambda+antiSigma0+1.1*antiSigma-)/antiproton ratio at the AGS does not necessarily imply the formation of the QGP. We further study the excitation function of the ratio in UrQMD, which may help in the search and study of the QGP.

  6. Effect of source tuning parameters on the plasma potential of heavy ions in the 18 GHz high temperature superconducting electron cyclotron resonance ion source

    SciTech Connect (OSTI)

    Rodrigues, G.; Mathur, Y.; Kumar, Sarvesh; Mandal, A.; Kanjilal, D.; Roy, A. [Inter University Accelerator Centre, Aruna Asaf Ali Marg, New Delhi (India); Baskaran, R. [Indira Gandhi Centre for Atomic Research, Kalpakkam, Tamil Nadu (India); Kukrety, S. [Department of Physics, Kirori Mal College, Delhi University (India)

    2012-03-15T23:59:59.000Z

    Plasma potentials for various heavy ions have been measured using the retarding field technique in the 18 GHz high temperature superconducting ECR ion source, PKDELIS [C. Bieth, S. Kantas, P. Sortais, D. Kanjilal, G. Rodrigues, S. Milward, S. Harrison, and R. McMahon, Nucl. Instrum. Methods B 235, 498 (2005); D. Kanjilal, G. Rodrigues, P. Kumar, A. Mandal, A. Roy, C. Bieth, S. Kantas, and P. Sortais, Rev. Sci. Instrum. 77, 03A317 (2006)]. The ion beam extracted from the source is decelerated close to the location of a mesh which is polarized to the source potential and beams having different plasma potentials are measured on a Faraday cup located downstream of the mesh. The influence of various source parameters, viz., RF power, gas pressure, magnetic field, negative dc bias, and gas mixing on the plasma potential is studied. The study helped to find an upper limit of the energy spread of the heavy ions, which can influence the design of the longitudinal optics of the high current injector being developed at the Inter University Accelerator Centre. It is observed that the plasma potentials are decreasing for increasing charge states and a mass effect is clearly observed for the ions with similar operating gas pressures. In the case of gas mixing, it is observed that the plasma potential minimizes at an optimum value of the gas pressure of the mixing gas and the mean charge state maximizes at this value. Details of the measurements carried out as a function of various source parameters and its impact on the longitudinal optics are presented.

  7. Determination of Dose From Light Charged Ions Relevant to Hadron Therapy Using the Particle and Heavy Ion Transport System (PHITS)

    E-Print Network [OSTI]

    Butkus, Michael Patrick

    2011-10-21T23:59:59.000Z

    .................................................................. 10 Quality Factor for Charged Particles .............................................. 13 Effects of Dose Fractionation ......................................................... 15 Fragmentation and Scattering... for Various Ion Beams ...................................................... 33 15 Dose Percentage Rates for Various Ion Beams in a Tumor and in Different Regions of a Body Relative to the Tumor .............................. 36 16 Quality Factors...

  8. Swift heavy ion induced structural and optical properties of Y{sub 2}O{sub 3}:Eu{sup 3+} nanophosphor

    SciTech Connect (OSTI)

    Som, S. [Department of Applied Physics, Indian School of Mines, Dhanbad 826004 (India)] [Department of Applied Physics, Indian School of Mines, Dhanbad 826004 (India); Sharma, S.K., E-mail: sksharma.ism@gmail.com [Department of Applied Physics, Indian School of Mines, Dhanbad 826004 (India); Lochab, S.P. [Inter University Accelerator Centre, New Delhi 110067 (India)] [Inter University Accelerator Centre, New Delhi 110067 (India)

    2013-02-15T23:59:59.000Z

    Highlights: ? Europium doped yttrium oxide nanophosphor was synthesized via combustion method. ? Prepared nanophosphor was irradiated by 150 MeV Swift heavy ion (Ni{sup 7+}). ? Structural (XRD, FTIR, and TEM) and optical properties (DR and PL) after ion irradiation were studied. ? Band gap increases with ion fluence due to the decrease in average crystallite size. -- Abstract: This paper reports the structural and optical modifications of Y{sub 2}O{sub 3}:Eu{sup 3+} nanophosphor induced by 150 MeV Ni{sup 7+} swift heavy ions (SHI) in the fluence range 1 × 10{sup 11} to 1 × 10{sup 13} ions/cm{sup 2}. The XRD, TEM and FTIR studies confirm the loss of crystallinity of the nanophosphors after ion irradiation. Diffuse reflectance spectrum shows a blue shift in the absorption band for SHI induced nanophosphors. An increase in the intensity of photoluminescence peaks without any shift in the peak positions was observed.

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

    E-Print Network [OSTI]

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

    2006-01-01T23:59:59.000Z

    . Tai et al. (STAR Collaboration), J. Phys. G 30, S809 (2004). [34] J. Dunkel and P. Ha?nggi, Phys. Rev. E 71, 016124 (2005). [35] P. Arnold, Phys. Rev. E 61, 6099 (2000). [36] X. Dong et al., Phys. Lett. B597, 328 (2004). [37] V. Greco, C. M. Ko...

  10. Solenoid transport of a heavy ion beam for warm dense matterstudies and inertial confinement fusion

    SciTech Connect (OSTI)

    Armijo, Julien

    2006-10-01T23:59:59.000Z

    From February to July 2006, I have been doing research as a guest at Lawrence Berkeley National Laboratory (LBNL), in the Heavy Ion Fusion group. This internship, which counts as one semester in my master's program in France, I was very pleased to do it in a field that I consider has the beauty of fundamental physics, and at the same time the special appeal of a quest for a long-term and environmentally-respectful energy source. During my stay at LBNL, I have been involved in three projects, all of them related to Neutralized Drift Compression Experiment (NDCX). The first one, experimental and analytical, has consisted in measuring the effects of the eddy currents induced by the pulsed magnets in the conducting plates of the source and diagnostic chambers of the Solenoid Transport Experiment (STX, which is a subset of NDCX). We have modeled the effect and run finite-element simulations that have reproduced the perturbation to the field. Then, we have modified WARP, the Particle-In-Cell code used to model the whole experiment, in order to import realistic fields including the eddy current effects and some details of each magnet. The second project has been to take part in a campaign of WARP simulations of the same experiment to understand the leakage of electrons that was observed in the experiment as a consequence to some diagnostics and the failure of the electrostatic electron trap. The simulations have shown qualitative agreement with the measured phenomena, but are still in progress. The third project, rather theoretical, has been related to the upcoming target experiment of a thin aluminum foil heated by a beam to the 1-eV range. At the beginning I helped by analyzing simulations of the hydrodynamic expansion and cooling of the heated material. But, progressively, my work turned into making estimates for the nature of the liquid/vapor two-phase flow. In particular, I have been working on criteria and models to predict the formation of droplets, their size, and their partial or total evaporation in the expanding flow.

  11. Effects of N-Asterisk(1440) Resonance on Particle-Production in Heavy-Ion Collisions at Subthreshold Energies 

    E-Print Network [OSTI]

    Li, Ba; Ko, Che Ming; LI, GQ.

    1994-01-01T23:59:59.000Z

    and broaden- ing width of 5 resonance are well known [24] and have been a subject of much interest. On the contrary, little is known about the in-medium behavior of higher resonances. The very recent analysis of photoabsorption cross sections on nu- clei.... Rev. Nucl. Part. Sci. 41, 29 (1991). [4] W. Bauer, summary talk at the 9th High Energy Heavy Ion Study (Report No. MSUCL-917, 1994). [5] V. Metag, Frog. Part. Nucl. Phys. 30, 75 (1993); Nucl. Phys. A553, 283c (1993). [6] Gy. Wolf et al. , Nucl...

  12. Experimental plan for investigating building-earth heat transfer at the Joint Institute for Heavy Ion Research Building

    SciTech Connect (OSTI)

    Childs, K.W.

    1980-11-01T23:59:59.000Z

    An experimental plan is presented for investigating heat transfer between below-grade portions of building envelopes and the surrounding soil. Included is a detailing of data to be collected at an earth-sheltered structure (Joint Institute for Heavy Ion Research Building) to be constructed at Oak Ridge National Laboratory. The attributes of the required data collection instrumentation are defined and a program to assure the accuracy of the collected data is discussed. The experimental plan is intended to be used as a guide to selection, installation, and maintenance of instrumentation as well as in data collection and verification.

  13. Signature of smooth transition from diabatic to adiabatic states in heavy-ion fusion reactions at deep subbarrier energies

    E-Print Network [OSTI]

    Takatoshi Ichikawa; Kouichi Hagino; Akira Iwamoto

    2009-09-12T23:59:59.000Z

    We propose a novel extension of the standard coupled-channels framework for heavy-ion reactions in order to analyze fusion reactions at deep subbarrier incident energies. This extension simulates a smooth transition between the diabatic two-body and the adiabatic one-body states. To this end, we damp gradually the off-diagonal part of the coupling potential, for which the position of the onset of the damping varies for each eigen channel. We show that this model accounts well for the steep falloff of the fusion cross sections for the $^{16}$O+$^{208}$Pb, $^{64}$Ni+$^{64}$Ni, and $^{58}$Ni+$^{58}$Ni reactions.

  14. Isospin Effects in Heavy-Ion Collisions: Some Results From CHIMERA Experiments At LNS And Perspectives With Radioactive Beams

    SciTech Connect (OSTI)

    Cardella, G.; De Filippo, E.; Pagano, A.; Papa, M.; Pirrone, S.; Verde, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Amorini, F.; Cavallaro, S.; Lombardo, I.; Porto, F.; Rizzo, F.; Russotto, P. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Anzalone, A.; Maiolino, C. [INFN Lab. Naz. del Sud, Via S. Sofia 44-95123 Catania (Italy); Arena, N.; Geraci, E.; Grassi, L.; Lo Nigro, S.; Politi, G. [INFN, Sez di Catania, Via S. Sofia 64-95123 Catania (Italy); Dep. of Phys. and Astr. Univ. Catania Via S. Sofia 64-95123 Catania (Italy); Auditore, L. [INFN and Dep. of Phys. Univ. Messina (Italy)] (and others)

    2009-05-04T23:59:59.000Z

    CHIMERA is a 4{pi} multidetector for charged particles available at Laboratori Nazionali del Sud (INFN-LNS). A new method to measure the time scale of the emission of nuclear fragments is described, together with some applications in the field of the isospin dynamics of heavy-ion collisions. Competition between fusion-like and binary reactions near the energy threshold for nuclear multifragmentation is discussed. Opportunities are pointed out to use the detector at low and intermediate energies using the kinematical-coincidence method.

  15. Fast six-channel pyrometer for warm-dense-matter experiments with intense heavy-ion beams

    SciTech Connect (OSTI)

    Ni, P.A.; Kulish, M.I.; Mintsev, V.; Nikolaev, D.N.; Ternovoi, V.Ya.; Hoffmann, D.H.H.; Udrea, S.; Tahir, N.A.; Varentsov, D.; Hug, A.

    2008-12-01T23:59:59.000Z

    This paper describes a fast multi-channel radiation pyrometer that was developed for warmdense-matter experiments with intense heavy ion beams at Gesellschaft fur Schwerionenforschung mbH (GSI). The pyrometer is capable of measuring of brightness temperatures from 2000 K to 50000 K, at 6 wavelengths in visible and near-infrared parts of spectrum, with 5 nanosecond temporal resolution and several micrometers spatial resolution. The pyrometer's spectral discrimination technique is based on interference filters, which act as filters and mirrors to allow for simultaneous spectral discrimination of the same ray at multiple wavelengths.

  16. 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.

    2011-01-01T23:59:59.000Z

    , United Kingdom 3Brookhaven National Laboratory, Upton, New York 11973, USA 4University of California, Berkeley, California 94720, USA 5University of California, Davis, California 95616, USA 6University of California, Los Angeles, California 90095, USA... Collider (RHIC) is believed to result in a novel state of hot and dense matter with properties strikingly different from that of a hadron gas or ordinary nuclear matter [2]. The bulk properties of particle production are studied using identified...

  17. Nano-porosity in GaSb induced by swift heavy ion irradiation

    SciTech Connect (OSTI)

    Kluth, P., E-mail: patrick.kluth@anu.edu.au; Schnohr, C. S.; Giulian, R.; Araujo, L. L.; Lei, W.; Rodriguez, M. D.; Afra, B.; Bierschenk, T.; Ridgway, M. C. [Department of Electronic Materials Engineering, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Sullivan, J.; Weed, R. [ARC Centre for Antimatter-Matter Studies, AMPL, Research School of Physics and Engineering, Australian National University, Canberra, Australian Capital Territory 0200 (Australia); Li, W.; Ewing, R. C. [Department of Earth and Environmental Sciences, University of Michigan, Ann Arbor, Michigan 48109-1005 (United States)

    2014-01-13T23:59:59.000Z

    Nano-porous structures form in GaSb after ion irradiation with 185 MeV Au ions. The porous layer formation is governed by the dominant electronic energy loss at this energy regime. The porous layer morphology differs significantly from that previously reported for low-energy, ion-irradiated GaSb. Prior to the onset of porosity, positron annihilation lifetime spectroscopy indicates the formation of small vacancy clusters in single ion impacts, while transmission electron microscopy reveals fragmentation of the GaSb into nanocrystallites embedded in an amorphous matrix. Following this fragmentation process, macroscopic porosity forms, presumably within the amorphous phase.

  18. The potential application of ultra-nanocrystalline diamond films for heavy ion irradiation detection

    SciTech Connect (OSTI)

    Chen, Huang-Chin [Department of Physics, Tamkang University, Tamsui, New-Taipei, Taiwan 251 (China); Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan, 300 (China); Chen, Shih-Show [Department of Physics, Tamkang University, Tamsui, New-Taipei, Taiwan 251 (China); Department of Information Technology and Mobile Communication, Taipei College of Maritime Technology, Tamsui, New-Taipei, Taiwan 251 (China); Wang, Wei-Cheng; Lin, I-Nan; Chang, Ching-Lin [Department of Physics, Tamkang University, Tamsui, New-Taipei, Taiwan 251 (China); Lee, Chi-Young [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu, Taiwan, 300 (China); Guo, Jinghua [Advanced Light Source, Lawrence Berkeley National Laboratory, Berkeley, CA 94720 (United States)

    2013-06-15T23:59:59.000Z

    The potential of utilizing the ultra-nanocrystalline (UNCD) films for detecting the Au-ion irradiation was investigated. When the fluence for Au-ion irradiation is lower than the critical value (f{sub c}= 5.0 Multiplication-Sign 10{sup 12} ions/cm{sup 2}) the turn-on field for electron field emission (EFE) process of the UNCD films decreased systematically with the increase in fluence that is correlated with the increase in sp{sup 2}-bonded phase ({pi}{sup *}-band in EELS) due to the Au-ion irradiation. The EFE properties changed irregularly, when the fluence for Au-ion irradiation exceeds this critical value. The transmission electron microscopic microstructural examinations, in conjunction with EELS spectroscopic studies, reveal that the structural change preferentially occurred in the diamond-to-Si interface for the samples experienced over critical fluence of Au-ion irradiation, viz. the crystalline SiC phase was induced in the interfacial region and the thickness of the interface decreased. These observations implied that the UNCD films could be used as irradiation detectors when the fluence for Au-ion irradiation does not exceed such a critical value.

  19. Nanoscale density fluctuations in swift heavy ion irradiated amorphous SiO{sub 2}

    SciTech Connect (OSTI)

    Kluth, P.; Giulian, R.; Ridgway, M. C. [Department of Electronic Materials Engineering, Australian National University, Canberra ACT 0200 (Australia); Pakarinen, O. H.; Djurabekova, F.; Nordlund, K. [Department of Physics and Helsinki Institute of Physics, University of Helsinki, Helsinki (Finland); Byrne, A. P. [Department of Nuclear Physics, Australian National University, Canberra ACT 0200 (Australia)

    2011-12-15T23:59:59.000Z

    We report on the observation of nanoscale density fluctuations in 2 {mu}m thick amorphous SiO{sub 2} layers irradiated with 185 MeV Au ions. At high fluences, in excess of approximately 5 x 10{sup 12} ions/cm{sup 2}, where the surface is completely covered by ion tracks, synchrotron small angle x-ray scattering measurements reveal the existence of a steady state of density fluctuations. In agreement with molecular dynamics simulations, this steady state is consistent with an ion track ''annihilation'' process, where high-density regions generated in the periphery of new tracks fill in low-density regions located at the center of existing tracks.

  20. U.S. Heavy Ion Beam Science towards inertial fusion energy

    E-Print Network [OSTI]

    2002-01-01T23:59:59.000Z

    Science towards Inertial Fusion Energy B.G. Logan 1), D.activities for inertial fusion energy at Lawrence LivermoreIon Fusion in the U.S. Fusion Energy Sciences Program [25].

  1. EBIT spectroscopy of highly charged heavy ions relevant to hot plasmas

    SciTech Connect (OSTI)

    Nakamura, Nobuyuki [Institute for Laser Science, University of Electro-Communications, Tokyo 182-8585 (Japan); National Institute for Fusion Science, Gifu 509-5292 (Japan); Ding Xiaobin; Dong Chenzhong [North West Normal University, Lanzhou 730070 (China); Hara, Hirohisa; Watanabe, Tetsuya [National Astronomical Observatory of Japan, Tokyo 181-8588 (Japan); Kato, Daiji; Murakami, Izumi; Sakaue, Hiroyuki A. [National Institute for Fusion Science, Gifu 509-5292 (Japan); Koike, Fumihiro [School of Medicine, Kitasato University, Kanagawa 252-0373 (Japan); Nakano, Tomohide [Japan Atomic Energy Agency, Ibaraki 311-0193 (Japan); Ohashi, Hayato [Institute for Laser Science, University of Electro-Communications, Tokyo 182-8585 (Japan); Watanabe, Hirofumi; Yamamoto, Norimasa [Chubu University, Aichi 487-8501 (Japan)

    2013-07-11T23:59:59.000Z

    We present spectra of highly charged iron, gadolinium, and tungsten ions obtained with electron beam ion traps. Spectroscopic studies of these ions are important to diagnose and control hot plasmas in several areas. For iron ions, the electron density dependence of the line intensity ratio in extreme ultraviolet spectra is investigated for testing the model calculation used in solar corona diagnostics. Soft x-ray spectra of gadolinium are studied to obtain atomic data required in light source development for future lithography. Tungsten is considered to be the main impurity in the ITER plasma, and thus visible and soft x-ray spectra of tungsten have been observed to explore the emission lines useful for the spectroscopic diagnostics of the ITER plasma.

  2. RF CAVITY PERFORMANCE in the ISAC-II SUPERCONDUCTING HEAVY ION...

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

    quarter wave interdigital loading structure are used for the Positive Ion Injector (PII). *Lowest frequency 48.5MHz QWR and lowest 0.008 ever built (by a factor of five) *...

  3. Bremsstrahlung from relativistic heavy ions in a fixed target experiment at the LHC

    E-Print Network [OSTI]

    Mikkelsen, Rune E; Uggerhøj, Ulrik I

    2015-01-01T23:59:59.000Z

    We calculate the emission of bremsstrahlung from lead and argon ions in A Fixed Target ExpeRiment (AFTER) that uses the LHC beams. With nuclear charges of $Ze$ equal $208$ and $18$ respectively, these ions are accelerated to energies of $7$ TeV$\\times Z $. The bremsstrahlung peaks around $\\approx 100$ GeV and the spectrum exposes the nuclear structure of the incoming ion. The peak structure is significantly different from the flat power spectrum pertaining to a point charge. Photons are predominantly emitted within an angle of $1/\\gamma$ to the direction of ion propagation. Our calculations are based on the Weizs\\"{a}cker-Williams method of virtual quanta with application of existing experimental data on photonuclear interactions.

  4. Bremsstrahlung from relativistic heavy ions in a fixed target experiment at the LHC

    E-Print Network [OSTI]

    Rune E. Mikkelsen; Allan H. Sørensen; Ulrik I. Uggerhøj

    2015-03-23T23:59:59.000Z

    We calculate the emission of bremsstrahlung from lead and argon ions in A Fixed Target ExpeRiment (AFTER) that uses the LHC beams. With nuclear charges of $Ze$ equal $208$ and $18$ respectively, these ions are accelerated to energies of $7$ TeV$\\times Z $. The bremsstrahlung peaks around $\\approx 100$ GeV and the spectrum exposes the nuclear structure of the incoming ion. The peak structure is significantly different from the flat power spectrum pertaining to a point charge. Photons are predominantly emitted within an angle of $1/\\gamma$ to the direction of ion propagation. Our calculations are based on the Weizs\\"{a}cker-Williams method of virtual quanta with application of existing experimental data on photonuclear interactions.

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

    E-Print Network [OSTI]

    van Hees, H.; Rapp, Ralf.

    2005-01-01T23:59:59.000Z

    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...

  6. Off-shell effects in Higgs decays to heavy gauge bosons and signal-background interference in Higgs decays to photons at a linear collider

    E-Print Network [OSTI]

    Liebler, Stefan

    2015-01-01T23:59:59.000Z

    We discuss off-shell contributions in Higgs decays to heavy gauge bosons $H\\rightarrow VV^{(*)}$ with $V\\in\\lbrace Z,W\\rbrace$ for a standard model (SM) Higgs boson for both dominant production processes $e^+e^-\\rightarrow ZH\\rightarrow ZVV^{(*)}$ and $e^+e^-\\rightarrow \

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

    E-Print Network [OSTI]

    Gurrola, Alfredo

    2011-10-21T23:59:59.000Z

    that may lead to events with highly energetic tau lepton pairs. In this dissertation, focus is placed on a possible search for new heavy gauge bosons decaying to highly energetic tau pairs using a data sample corresponding to an integrated luminosity of 36...

  8. 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

    1995-04-05T23:59:59.000Z

    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.

  9. Absence of Thermophoretic Flow in Relativistic Heavy-Ion Collisions as an Indicator for the Absence of a Mixed Phase

    E-Print Network [OSTI]

    Markus H. Thoma

    2002-04-30T23:59:59.000Z

    If a quark-gluon plasma is formed in relativistic heavy-ion collisions, there may or may not be a mixed phase of quarks, gluons and hadronic clusters when the critical temperature is reached in the expansion of the fireball. If there is a temperature gradient in the fireball, the hadronic clusters, embedded in the heat bath of quarks and gluons, are subjected to a thermophoretic force. It is shown that even for small temperature gradients and short lifetimes of the mixed phase, thermophoresis would lead to a flow essentially stronger than the observed one. The absence of this strong flow provides support for a rapid or sudden hadronization mechanism without a mixed phase.

  10. The effects of topological charge change in heavy ion collisions: "Event by event P and CP violation"

    E-Print Network [OSTI]

    Dmitri E. Kharzeev; Larry D. McLerran; Harmen J. Warringa

    2007-11-06T23:59:59.000Z

    Quantum chromodynamics (QCD) contains field configurations which can be characterized by a topological invariant, the winding number Q_w. Configurations with nonzero Q_w break the charge-parity CP symmetry of QCD. We consider a novel mechanism by which these configurations can separate charge in the presence of a background magnetic field - the "Chiral Magnetic Effect". We argue that sufficiently large magnetic fields are created in heavy ion collisions so that the Chiral Magnetic Effect causes preferential emission of charged particles along the direction of angular momentum. Since separation of charge is CP-odd, any observation of the Chiral Magnetic Effect could provide a clear demonstration of the topological nature of the QCD vacuum. We give an estimate of the effect and conclude that it might be observed experimentally.

  11. Medium modifications of photon-tagged jet fragmentation function in high-energy heavy-ion collisions

    E-Print Network [OSTI]

    Guo-Liang Ma

    2014-06-24T23:59:59.000Z

    Based on a multiphase transport model, medium modifications of prompt photon-tagged jet fragmentation function are investigated by comparing prompt photon-tagged hadron azimuthal correlation in Au+Au collisions (0-40\\%) with that in p+p collisions at $\\sqrt{s_{_{\\rm NN}}}$ = 200 GeV. The measured modification factor, $I_{AA}$, increases with the increasing integration range of the away side, which reveals a medium-modified jet shape in which the medium enhancement of soft particles is preferentially located far away from the jet axis. The $I_{AA}$ largely results from strong interactions between jets and partonic matter. However, both hadronization of coalescence and hadronic rescatterings play certain roles to modify the $I_{AA}$. These behaviors reflect a dynamical evolution of modifications of the prompt photon-tagged jet fragmentation function in high-energy heavy-ion collisions.

  12. Radial profile measurements of plasma pressure-like fluctuations with the heavy ion beam diagnostic on the tokamak ISTTOK

    SciTech Connect (OSTI)

    Henriques, R. B., E-mail: rhenriques@ipfn.ist.utl.pt; Malaquias, A.; Nedzelskiy, I. S.; Silva, C.; Coelho, R.; Figueiredo, H.; Fernandes, H. [Instituto de Plasmas e Fusão Nuclear, Instituto Superior Técnico, Universidade de Lisboa, 1049-001 Lisboa (Portugal)

    2014-11-15T23:59:59.000Z

    The Heavy Ion Beam Diagnostic (HIBD) on the tokamak ISTTOK (Instituto Superior Técnico TOKamak) has been modified, in terms of signal conditioning, to measure the local fluctuations of the n{sub e}?{sub 1,2}(T{sub e}) product (plasma density times the effective ionization cross-section) along the tokamak minor diameter, in 12 sample volumes in the range of ?0.7a < r < 0.7a, with a maximum delay time of 1 ?s. The corresponding signals show high correlation with the magnetic Mirnov coils in the characteristic MHD frequency range of ISTTOK plasmas and enable the identification of tearing modes. This paper describes the HIBD signal conditioning system and presents a preliminary analysis of the radial profile measurements of local n{sub e}?{sub 1,2}(T{sub e}) fluctuations.

  13. On the balance energy and nuclear dynamics in peripheral heavy-ion collisions

    E-Print Network [OSTI]

    Rajiv Chugh; Rajeev K. Puri

    2010-03-16T23:59:59.000Z

    We present here the system size dependence of balance energy for semi-central and peripheral collisions using quantum molecular dynamics model. For this study, the reactions of $Ne^{20}+Ne^{20}$, $Ca^{40}+Ca^{40}$, $Ni^{58}+Ni^{58}$, $Nb^{93}+Nb^{93}$, $Xe^{131}+Xe^{131}$ and $Au^{197}+Au^{197}$ are simulated at different incident energies and impact parameters. A hard equation of state along with nucleon-nucleon cross-sections between 40 - 55 mb explains the data nicely. Interestingly, balance energy follows a power law $\\propto{A^{\\tau}}$ for the mass dependence at all colliding geometries. The power factor $\\tau$ is close to -1/3 in central collisions whereas it is -2/3 for peripheral collisions suggesting stronger system size dependence at peripheral geometries. This also suggests that in the absence of momentum dependent interactions, Coulomb's interaction plays an exceedingly significant role. These results are further analyzed for nuclear dynamics at the balance point.

  14. On the balance energy and nuclear dynamics in peripheral heavy-ion collisions

    E-Print Network [OSTI]

    Chugh, Rajiv

    2010-01-01T23:59:59.000Z

    We present here the system size dependence of balance energy for semi-central and peripheral collisions using quantum molecular dynamics model. For this study, the reactions of $Ne^{20}+Ne^{20}$, $Ca^{40}+Ca^{40}$, $Ni^{58}+Ni^{58}$, $Nb^{93}+Nb^{93}$, $Xe^{131}+Xe^{131}$ and $Au^{197}+Au^{197}$ are simulated at different incident energies and impact parameters. A hard equation of state along with nucleon-nucleon cross-sections between 40 - 55 mb explains the data nicely. Interestingly, balance energy follows a power law $\\propto{A^{\\tau}}$ for the mass dependence at all colliding geometries. The power factor $\\tau$ is close to -1/3 in central collisions whereas it is -2/3 for peripheral collisions suggesting stronger system size dependence at peripheral geometries. This also suggests that in the absence of momentum dependent interactions, Coulomb's interaction plays an exceedingly significant role. These results are further analyzed for nuclear dynamics at the balance point.

  15. Simulating Electron Effects in Heavy-Ion Accelerators with Solenoid Focusing

    SciTech Connect (OSTI)

    Sharp, W. M.; Grote, D. P.; Cohen, R. H.; Friedman, A.; Molvik, A. W.; Vay, J.-L.; Seidl, P. A.; Roy, P. K.; Coleman, J. E.; Haber, I.

    2007-06-20T23:59:59.000Z

    Contamination from electrons is a concern for solenoid-focused ion accelerators being developed for experiments in high-energy-density physics. These electrons, produced directly by beam ions hitting lattice elements or indirectly by ionization of desorbed neutral gas, can potentially alter the beam dynamics, leading to a time-varying focal spot, increased emittance, halo, and possibly electron-ion instabilities. The electrostatic particle-in-cell code WARP is used to simulate electron-cloud studies on the solenoid-transport experiment (STX) at Lawrence Berkeley National Laboratory. We present self-consistent simulations of several STX configurations and compare the results with experimental data in order to calibrate physics parameters in the model.

  16. Spin-rotation coupling in non-exponential decay of hydrogenlike heavy ions

    E-Print Network [OSTI]

    G. Lambiase; G. Papini; G. Scarpetta

    2008-11-14T23:59:59.000Z

    We discuss a model in which a recently reported modulation in the decay of the hydrogenlike ions ${}^{140}$Pr$^{58 +}$ and ${}^{142}$Pm$^{60 +}$ arises from the coupling of rotation to the spin of electron and nuclei (Thomas precession). A similar model describes the electron modulation in muon $ g-2$ experiments correctly. Agreement with the GSI experimental results is obtained for the current QED-values of the bound electron g-factors, $g({}^{140}$Pr$^{58 +})=1.872$ and $g({}^{142}$Pm$^{60 +})=1.864$, if the Lorentz factor of the bound electron is $\\sim 1.88$. The latter is fixed by either of the two sets of experimental data. The model predicts that the modulation is not observable if the motion of the ions is linear, or if the ions are stopped in a target.

  17. Detection of high-energy heavy ions using piezoelectric lead zirconate titanate

    SciTech Connect (OSTI)

    Takechi, Seiji; Morinaga, Shin-ya; Kurozumi, Atsuma [Graduate School of Engineering, Osaka City University, Osaka 558-8585 (Japan); Miyachi, Takashi; Fujii, Masayuki; Hasebe, Nobuyuki [Advanced Research Institute for Science and Engineering, Waseda University, Tokyo 169-8555 (Japan); Shibata, Hiromi [Graduate School of Engineering, Kyoto University, Kyoto 606-8501 (Japan); Murakami, Takeshi; Uchihori, Yukio [National Institute of Radiological Sciences, Chiba 263-8555 (Japan); Okada, Nagaya [Honda Electronics Co., Ltd., Aichi 441-3193 (Japan)

    2009-04-15T23:59:59.000Z

    The characteristics of a radiation detector fabricated with stacks of piezoelectric lead zirconate titanate (PZT) elements were studied by irradiating it with a 400 MeV/n xenon (Xe) beam for various beam pulse durations. This detector is referred to as the multilayered detector (MD). To understand the production mechanism behind the output voltage obtained from the MD, measurement of the spatial distribution of the output signals generated in the MD was attempted. It was found that the amplitude observed was dependent on the number of Xe ions per unit time and the amount of ionization loss energy of Xe ions in PZT.

  18. The Heavy Ion Fusion Science Virtual National Laboratory Physics of neutralization of

    E-Print Network [OSTI]

    Kaganovich, Igor

    everywhere (c). P.K. Roy et al, NIMPR A 544, 225 (2005). #12;#5 Radial Compression requires degreeV K+ ion beam: (a) without plasma (b) with plasma. NTX experiments, P.K. Roy et al, NIMPR. A 544, 225. Startsev, A. B. Sefkow Princeton Plasma Physics Laboratory E. P. Lee, A. Friedman Lawrence Berkeley

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

    E-Print Network [OSTI]

    Li, Ba; Ko, Che Ming.

    1996-01-01T23:59:59.000Z

    . The average transverse momentum of kaons in the re- action plane for Au1Au reactions at Pbeam /A5 4 GeV/c ~upper window! and 12 GeV/c ~lower window! at impact parameters less than 4 fm. The open ~filled! circles are the results obtained with ~without... and azimuthal angle distributions. We find that th studying the kaon dispersion relation in dense medium PACS number~s!: 25.75.Ld, 13.75.Jz, 21.65.1f The properties of a kaon in the extremely hot and dense enviroment created in relativistic heavy...

  20. atp-gated p2x4 ion: Topics by E-print Network

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

    using specific Sgula, Philippe 5 Ion Colliders CERN Preprints Summary: High-energy ion colliders are large research tools in nuclear physics to study the...

  1. HISTRAP: Proposal for a Heavy Ion Storage Ring for Atomic Physics

    SciTech Connect (OSTI)

    Not Available

    1988-11-01T23:59:59.000Z

    This paper presents an overview of the physics capabilities of HISTRAP together with a brief description of the facility and a sampling of the beams which will be available for experimentation, and surveys some of the lines of investigation in the physics of multicharged ions, molecular ion spectroscopy, condensed beams, and nuclear physics that will become possible with the advent of HISTRAP. Details of the accelerator design are discussed, including computer studies of beam tracking in the HISTRAP lattice, a discussion of the HHIRF tandem and ECR/RFQ injectors, and a description of the electron beam cooling system. In the past three years, HISTRAP has received substantial support from Oak Ridge National Laboratory management and staff. The project has used discretionary funds to develop hardware prototypes and carry out design studies. Construction has been completed on a vacuum test stand which models 1/16 of the storage ring and has attained a pressure of 4 x 10/sup -12/ Torr; a prototype rf cavity capable of accelerating beams up to 90 MeV/nucleon and decelerating to 20 keV/nucleon; and a prototype dipole magnet, one of the eight required for the HISTRAP lattice. This paper also contains a summary of the work on electron cooling carried out by one of our staff members at CERN. Building structures and services are described. Details of cost and schedule are also discussed. 77 refs.

  2. Elucidating the event-by-event flow fluctuations in heavy-ion collisions via the event shape selection technique

    E-Print Network [OSTI]

    Peng Huo; Jiangyong Jia; Soumya Mohapatra

    2014-09-11T23:59:59.000Z

    The presence of large event-by-event flow fluctuations in heavy ion collisions at RHIC and the LHC provides an opportunity to study a broad class of flow observables. This paper explores the correlations among harmonic flow coefficients $v_n$ and their phases $\\Phi_n$, and the rapidity fluctuation of $v_n$. The study is carried out usin Pb+Pb events generated by the AMPT model with fixed impact parameter. The overall ellipticity/triangularity of events is varied by selecting on the eccentricities $\\epsilon_n$ or the magnitudes of the flow vector $q_n$ for n=2 and 3, respectively. The responses of the $v_n$, the event-plane correlations, and the rapidity fluctuations, to the change in $\\epsilon_n$ and $q_n$ are then systematized. Strong positive correlations are observed among all even harmonics $v_2, v_4$, and $v_6$ (all increase with $q_2$), between $v_2$ and $v_5$ (both increase with $q_2$) and between $v_3$ and $v_5$ (both increase with $q_3$), consistent with the effects of nonlinear collective response. In contrast, an anti-correlation is observed between $v_2$ and $v_3$ similar to that seen between $\\epsilon_2$ and $\\epsilon_3$. These correlation patterns are found to be independent of whether selecting on $q_n$ or $\\epsilon_n$, validating the ability of $q_n$ in selecting the initial geometry. A forward/backward asymmetry of $v_n(\\eta)$ is observed for events selected on $q_n$ but not on $\\epsilon_n$, reflecting dynamical fluctuations exposed by the $q_n$ selection. Many event-plane correlators show good agreement between $q_n$ and $\\epsilon_n$ selections, suggesting that their variations with $q_n$ are controlled by the change of $\\epsilon_n$ in the initial geometry. Hence these correlators may serve as promising observables for disentangling the fluctuations generated in various stages of the evolution of the matter created in heavy ion collisions.

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

    E-Print Network [OSTI]

    Yu. B. Ivanov

    2013-06-04T23:59:59.000Z

    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.

  4. X-ray absorption spectroscopy study of the local structure of heavy metal ions incorporated into electrodeposited nickel oxide films

    SciTech Connect (OSTI)

    Balasubramanian, M.; Melendres, C.A. [Argonne National Lab., IL (United States). Chemical Technology Div.] [Argonne National Lab., IL (United States). Chemical Technology Div.; Mansour, A.N. [Naval Surface Warfare Center, Bethesda, MD (United States). Carderock Div.] [Naval Surface Warfare Center, Bethesda, MD (United States). Carderock Div.

    1999-02-01T23:59:59.000Z

    The incorporation of heavy metal ions into simulated corrosion films has been investigated using spectroscopic and electrochemical techniques. The films were formed by electrodeposition of the appropriate oxide (hydroxide) onto a graphite substrate. Synchrotron X-ray absorption spectroscopy (XAS) was used to determine the structure and composition of the host oxide film, as well as the local structure of the impurity ion. Results on the incorporation of Ce and Sr into surface films of Ni(OH){sub 2} and NiOOH are reported. Cathodically deposited Ni(OH){sub 2} was found to be mainly in the alpha form while anodically prepared NiOOH showed the presence of Ni{sup +2} and Ni{sup +4}. Cerium incorporated into Ni(OH){sub 2} exists as mixed Ce{sup +3} and Ce{sup +4} phases; a Ce{sup +4} species was found when Ce was codeposited with NiOOH. The structure of the Ce{sup +4} phase in anodic films appears similar to a Ce(OH){sub 4} standard. However, XAS, X-ray diffraction, and laser Raman measurements indicate that the latter chemical formulation is probably incorrect and that the material is really a disordered form of hydrous cerium oxide. The local structure of this material is similar to CeO{sub 2} but has much higher structural disorder. The significance of this finding on the question of the structure of Ce-based corrosion inhibitors in aluminum oxide films is pointed out. Moreover, the authors found it possible to form pure Ce oxide (hydroxide) films on graphite by both cathodic and anodic electrodeposition; their structures have also been elucidated. Strontium incorporated into nickel oxide films consists of Sr{sup +2} which is coordinated to oxygen atoms and is likely to exist as small domains of coprecipitated material.

  5. Investigation of thermal processes in one-and two-layer materials under irradiation with high-energy heavy ions within the thermal peak model

    SciTech Connect (OSTI)

    Amirkhanov, I. V., E-mail: ibrohim@jinr.ru; Didyk, A. Yu.; Muzafarov, D. Z.; Puzynin, I. V.; Puzynina, T. P.; Sarker, N. R.; Sarhadov, I.; Sharipov, Z. A. [Joint Institute for Nuclear Research, Laboratory of Information Technologies (Russian Federation)

    2006-12-15T23:59:59.000Z

    A system of equations for the electron and lattice temperatures around and along the path of a 700-MeV heavy (uranium) ion in nickel (one-layer material) is solved numerically in the axially symmetric cylindrical coordinate system under the assumption of temperature-dependent specific heat and thermal conductivity. The obtained dependences of the lattice temperature on the radius (distance from the ion path) and depth suggest that the ionization energy loss of a 700-MeV uranium ion in nickel is sufficient to melt the material. A comparative analysis with the linear model is performed and the maximum radius and depth of the region where the target material can melt is estimated. Then, the initial system of equations is solved for the region around and along the path of a 710-MeV heavy (bismuth {sup 209}Bi) ion in the two-layer material Ni(2 {mu}m)-W with constant thermophysical parameters. The obtained dependences of the lattice temperature on the radius and depth show that the ionization energy loss of a 710-MeV bismuth ion in this two-layer material is sufficient for melting. The maximum radius and depth of the regions in the target material where phase transitions may occur are estimated.

  6. Implications of heavy-ion-induced satellite x-ray emission. III. Chemical effects in high resolution sulfur K/sub. cap alpha. / x-ray spectra

    SciTech Connect (OSTI)

    Vane, C.R.; Hulett, L.D. Jr.; Kahane, S.; McDaniel, F.D.; Milner, W.T.; Raman, S.; Rosseel, T.M.; Slaughter, G.G.; Varghese, S.L.; Young, J.P.

    1983-01-01T23:59:59.000Z

    High resolution (approx. 7 eV at 2.3 keV) sulfur K/sub ..cap alpha../ x-ray spectra have been obtained for a series of sulfur compound targets under heavy ion impact at the Holified Heavy Ion Facility. The spectra observed are dominated by a series of satellite peaks arising from varying degrees of L-shell ionization at the time of x-ray emission. Each spectral profile has been parameterized by a single variable p/sub L/, the apparent average L-shell ionization probability. Correlations are evident between p/sub L/ and the corresponding sulfur atom chemical environment. Much stronger correlations are however found for variations of some individual peak intensities with specific chemical parameters. Comparison of results for Ar/sup q+/ and Kr/sup q+/ projectiles shows that while L-shell ionization probability has increased, chemical sensitivity has apparently saturated.

  7. Time delays in heavy-ion-induced fission of medium-Z nuclei, measured by crystal blocking

    SciTech Connect (OSTI)

    Andersen, J. U. [Aarhus University; Chevallier, J. [University of Aarhus, Denmark; Forster, J. S. [Universite de Montreal; Karamian, S. A. [FLNR-JINR, Russia; Vane, C Randy [ORNL; Beene, James R [ORNL; Gross, Carl J [ORNL; Krause, Herbert F [ORNL; Liang, J Felix [ORNL; Shapira, Dan [ORNL; Uguzzoni, A. [University of Bologna

    2012-01-01T23:59:59.000Z

    Time delays in fission induced by bombardment of Mo with 170- and 180-MeV {sup 32}S, 225- and 240-MeV {sup 48}Ti, and 300-MeV {sup 58}Ni have been measured by observation of crystal blocking of fission fragments. In contrast to earlier measurements with a W target, the results are consistent with fission of a compound nucleus in competition with mainly neutron emission. Most of the fissions happen on a time scale much shorter than attoseconds but there is a significant component of fission with much longer lifetimes. The measurements are reproduced with a standard statistical model, including a Kramers correction to fission widths from the viscosity of hot nuclear matter. These new results support the interpretation of our earlier measurements with a W target, which indicate that there is a transition in heavy-ion-induced fission at large atomic number and mass, from multichance fission in the standard Bohr-Wheeler picture to fission without formation of a compound nucleus. The process is slowed down by nuclear viscosity, with measured delays of order attoseconds.

  8. Study Medium-induced Parton Energy Loss in Gamma+jet Events of High-Energy Heavy-Ion Collisions

    E-Print Network [OSTI]

    Xin-Nian Wang; Zheng Huang

    1997-01-09T23:59:59.000Z

    The effect of medium-induced parton energy loss on jet fragmentation is studied in high-energy heavy-ion collisions. It is shown that an effective jet fragmentation function can be extracted from the inclusive $p_T$ spectrum of charged particles in the opposite direction of a tagged direct photon with a fixed transverse energy. We study the modification of the effective jet fragmentation function due to parton energy loss in AA as compared to pp collisions, including $E_T$ smearing from initial state radiations for the photon-tagged jets. The effective fragmentation function at $z=p_T/E_T^\\gamma\\sim 1$ in pA collisions is shown to be sensitive to the additional $E_T$ smearing due to initial multiple parton scatterings whose effect must be subtracted out in AA collisions in order to extract the effective parton energy loss. Jet quenching in deeply inelastic lepton-nucleus scatterings as a measure of the parton energy loss in cold nuclear matter is also discussed. We also comment on the experimental feasibilities of the proposed study at the RHIC and LHC energies and some alternative measurements such as using $Z^0$ as a tag at the LHC energy.

  9. Charge Conjugation, Heavy Ions, e^+ e^- pairs: Was there a better way to add potentials to Dirac's free electrons?

    E-Print Network [OSTI]

    Samuel P. Bowen; Jay D. Mancini

    2012-03-26T23:59:59.000Z

    This is a study of a possible alternative procedure for adding a potential energy to the free electron Dirac equation. When Dirac added potentials to his free electron equation, there were two alternatives (here called D1 and D2). He chose D1 and lost charge conjugation symmetry, found Ehrenfest equations that depended on the sign of the energy of the state determining the expectation value, encountered Klein tunneling, zitterbewegung and the Klein paradox. The D1 alternative also predicted that deep potentials should pull positive energy states down into the negative energy continuum, possibly creating an unstable vacuum. Extensive experiments (1975-1997) found no evidence for this instability, but did find low energy electron-positron pairs with sharply defined energies and unusually low counting statistics. These pairs tended to disappear with higher beam currents. This paper explores the other alternative, here called D2 and finds charge conjugation symmetry preserved, Ehrenfest equations are classical, Klein tunneling is not present, unstable vacuua are forbidden, zitterbewegung is absent in the charge current density, new excitations of bound electron-positron pairs are possible in atoms, and the energies at which low energy electron-positron pair production in heavy ion scattering occurs is well described. Also all of the positive energy calculations, including those with the Coulomb potential, the hydrogen-like atom, are retained exactly the same as found in alternative D1. It might have been better if Dirac had chosen alternative D2.

  10. Entrance-channel mass-asymmetry dependence of compound nucleus formation time in light heavy-ion reactions

    SciTech Connect (OSTI)

    Szanto de Toledo, A. [Instituto de Fisica da Universidade de Sao Paulo, Departamento de Fisica Nuclear-Laboratorio, Pelletron, Caixa Postal 66318-05389-970 Sao Paulo, (Brasil)] [Instituto de Fisica da Universidade de Sao Paulo, Departamento de Fisica Nuclear-Laboratorio, Pelletron, Caixa Postal 66318-05389-970 Sao Paulo, (Brasil); Carlson, B.V. [Departamento de Fisica, Instituto Tecnologico da Aeronautica, Centro Tecnico Aerospacial, 12228-900 Sao Jose dos Campos, (Brasil)] [Departamento de Fisica, Instituto Tecnologico da Aeronautica, Centro Tecnico Aerospacial, 12228-900 Sao Jose dos Campos, (Brasil); Beck, C. [Centre de Recherches Nucleaires, Institut National de Physique Nucleaire et de Physique des Particules-Centre National de la Recherche Scientifique/Universite Louis Pasteur, Boite Postale 28, F-67037 Strasbourg Cedex 2 (France)] [Centre de Recherches Nucleaires, Institut National de Physique Nucleaire et de Physique des Particules-Centre National de la Recherche Scientifique/Universite Louis Pasteur, Boite Postale 28, F-67037 Strasbourg Cedex 2 (France); Thoennessen, M. [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)] [National Superconducting Cyclotron Laboratory and Department of Physics and Astronomy, Michigan State University, East Lansing, Michigan 48824 (United States)

    1996-12-01T23:59:59.000Z

    The entrance-channel mass-asymmetry dependence of the compound nucleus formation time in light heavy-ion reactions has been investigated within the framework of semiclassical dissipative collision models. The model calculations have been applied successfully to the formation of the {sup 38}Ar compound nucleus as populated via the {sup 9}Be+{sup 29}Si, {sup 11}B+{sup 27}Al, {sup 12}C+{sup 26}Mg, and {sup 19}F+{sup 19}F entrance channels. The shape evolution of several other light composite systems appears to be consistent with the so-called {open_quote}{open_quote}Fusion Inhibition Factor{close_quote}{close_quote} which has been observed experimentally. As found previously in more massive systems for the fusion-evaporation process, the entrance-channel mass-asymmetry degree of freedom appears to determine the competition between the different mechanisms as well as the time scales involved. {copyright} {ital 1996 The American Physical Society.}

  11. Jet Study in Ultra-Relativistic Heavy-Ion Collisions with the ALICE Detectors at the LHC

    E-Print Network [OSTI]

    Sarah-Louise Blyth

    2005-10-24T23:59:59.000Z

    In ultra-relativistic heavy-ion collisions at $\\sqrt{s_{NN}}$ = 5.5 TeV at the ALICE experiment at the LHC, interactions between the high-$p_{T}$ partons and the hot, dense medium produced in the collisions, are expected to lead to jet energy loss (jet-quenching) resulting in changes in the jet fragmentation functions as compared to the unquenched case. In order to reconstruct jet fragmentation functions, accurate information on the jet energy, direction and momentum distribution of the jet particles is needed. This thesis presents first results on jet reconstruction in simulated Pb+Pb collisions using the ALICE detectors and a UA1-based cone jet finding algorithm which has been modified and optimised to reconstruct high-$p_{T}$ jets on an event-by-event basis. Optimisation of the algorithm parameters and methods used to suppress the large background energy contribution while maximising the algorithm efficiency, are discussed and the resulting jet energy and direction resolutions are presented. Accurate jet reconstruction will allow measurement of the jet fragmentation functions and consequently the degree of quenching and therefore provide insight on the properties of the hot and dense medium (for example the initial gluon density) created in the collisions.

  12. Observation of charge-dependent azimuthal correlations and possible local strong parity violation in heavy-ion collisions

    SciTech Connect (OSTI)

    STAR Collaboration; Abelev, Betty

    2010-07-05T23:59:59.000Z

    Parity-odd domains, corresponding to non-trivial topological solutions of the QCD vacuum, might be created during relativistic heavy-ion collisions. These domains are predicted to lead to charge separation of quarks along the orbital momentum of the system created in non-central collisions. To study this effect, we investigate a three particle mixed harmonics azimuthal correlator which is a {Rho}-even observable, but directly sensitive to the charge separation effect. We report measurements of this observable using the STAR detector in Au+Au and Cu+Cu collisions at {radical}s{sub NN} = 200 and 62 GeV. The results are presented as a function of collision centrality, particle separation in rapidity, and particle transverse momentum. A signal consistent with several of the theoretical expectations is detected in all four data sets. We compare our results to the predictions of existing event generators, and discuss in detail possible contributions from other effects that are not related to parity violation.

  13. Measurement of heavy-flavor production in Pb-Pb collisions at the LHC with ALICE

    E-Print Network [OSTI]

    Robert Grajcarek; for the ALICE Collaboration

    2012-09-10T23:59:59.000Z

    A Large Ion Collider Experiment (ALICE) at the Large Hadron Collider (LHC) has been built in order to study the Quark-Gluon Plasma (QGP) created in high-energy nuclear collisions. As heavy-flavor quarks are produced at the early stage of the collision, they serve as sensitive probes for the QGP. The ALICE detector with its capabilities such as particle identification, secondary vertexing and tracking in a high multiplicity environment can address, among other measurements, the heavy-flavor sector in heavy-ion collisions. We present latest results on the measurement of the nuclear modification factor of open heavy-flavors as well as on the measurement of open heavy-flavor azimuthal anisotropy v2 in Pb-Pb collisions at sqrt(s) = 2.76 TeV. Open charmed hadrons are reconstructed in the hadronic decay channels D0->Kpi, D+->Kpipi, and D*+->D0pi applying a secondary decay-vertex topology. Complementary measurements are performed by detecting electrons (muons) from semi-leptonic decays of open heavy-flavor hadrons in the central (forward) rapidity region.

  14. LUCIAE 3.0: A new version of a computer program for Firecracker Model and rescattering in relativistic heavy-ion collisions

    E-Print Network [OSTI]

    Tai An; Sa Ben-Hao

    1998-04-01T23:59:59.000Z

    LUCIAE is a Monte Carlo program that, connected to FRITIOF, implements both the Firecracker Model (FCM), a possible mechanism for collective multi-gluon emission from the colour fields of interacting strings, and the reinteraction of the final state hadrons in relativistic heavy ion collisions. This paper includes a brief presentation of the dynamics of LUCIAE with an emphasis on the new features in this version, as well as a description of the program.

  15. Compositional analysis and depth profiling of thin film CrO{sub 2} by heavy ion ERDA and standard RBS: a comparison

    SciTech Connect (OSTI)

    Khamlich, S., E-mail: skhamlich@gmail.com [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); The African Laser Centre, CSIR campus, P.O. Box 395, Pretoria (South Africa); Msimanga, M., E-mail: mandla@tlabs.ac.za [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); iThemba LABS Gauteng, Private Bag 11, WITS 2050, Johannesburg (South Africa); Pineda-Vargas, C.A. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Faculty of Health and Wellness Sciences, C.P.U.T., P.O. Box 1906, Bellville 7535 (South Africa); Nuru, Z.Y. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); McCrindle, R. [Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); Maaza, M. [Nano-Sciences Laboratories, Materials Research Department, iThemba LABS, P.O. Box 722, Somerset West 7129 (South Africa); Department of Chemistry, Tshwane University of Technology, Private Bag X 680, Pretoria, 0001 (South Africa); The African Laser Centre, CSIR campus, P.O. Box 395, Pretoria (South Africa)

    2012-08-15T23:59:59.000Z

    Chromium dioxide (CrO{sub 2}) thin film has generated considerable interest in applied research due to the wide variety of its technological applications. It has been extensively investigated in recent years, attracting the attention of researchers working on spintronic heterostructures and in the magnetic recording industry. However, its synthesis is usually a difficult task due to its metastable nature and various synthesis techniques are being investigated. In this work a polycrystalline thin film of CrO{sub 2} was prepared by electron beam vaporization of Cr{sub 2}O{sub 3} onto a Si substrate. The polycrystalline structure was confirmed through XRD analysis. The stoichiometry and elemental depth distribution of the deposited film were measured by ion beam nuclear analytical techniques heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS), which both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. Moreover, the analysis carried out highlights the importance of complementary usage of the two techniques to obtain a more complete description of elemental content and depth distribution in thin films. - Graphical abstract: Heavy ion elastic recoil detection analysis (ERDA) and Rutherford backscattering spectrometry (RBS) both have relative advantage over non-nuclear spectrometries in that they can readily provide quantitative information about the concentration and distribution of different atomic species in a layer. Highlights: Black-Right-Pointing-Pointer Thin films of CrO{sub 2} have been grown by e-beam evaporation of Cr{sub 2}O{sub 3} target in vacuum. Black-Right-Pointing-Pointer The composition was determined by heavy ion-ERDA and RBS. Black-Right-Pointing-Pointer HI-ERDA and RBS provided information on the light and heavy elements, respectively.

  16. A vertical drift chamber as a high resolution focal plane detector for heavy ion spectroscopy with the Enge split-pole spectrometer

    E-Print Network [OSTI]

    Yates, Kenneth Warren

    1989-01-01T23:59:59.000Z

    67 71 74 79 V DESIGN OF A HYBRID FOCAL PLANE DETECTOR SYSTEM FOR HEAVY ION PARTICLE IDENTIFICATION 86 A. Particle Identification with the Hybrid Detector B. The Vertical Drift Chamber 1. Function and Design 2. Construction C. The Ionization.... 1. General Procedure to Identify and Remove Incorrect Drift Times 2. Results D. Determining the Origin of Major Drift Time Errors 139 144 152 152 156 166 D. PULSE FORMATION IN AN IONIZATION CHAMBER 170 VITA 174 LIST OF TABLES Page...

  17. Probing hot and dense matter production in heavy ion collisions via neutral mesons and photons with the ALICE detector at the LHC

    E-Print Network [OSTI]

    Astrid Morreale; for the ALICE collaboration

    2014-10-22T23:59:59.000Z

    One of the key signatures of the Quark Gluon Plasma (QGP) is the modification of hadron and direct photon spectra in heavy-ion collisions as compared to proton-proton (pp) collisions. Suppression of hadron production at high transverse momenta in heavy-ion collisions can be explained by the energy loss of the partons produced in the hard scattering processes which traverse the hot and dense QCD matter. The dependence of the observed suppression on the transverse momentum (pT) of the measured hadron towards higher pT is an important input for the theoretical understanding of jet quenching effects in the QGP and the nature of energy loss. Another key observable which has helped establish the energy loss picture, is high pT direct photon production for which no suppression is expected. For low pT photon production, it is expected that thermal sources will lead to enhancement of direct photons. We report an overview of photon and neutral meson production measurements by the ALICE experiment at the LHC in heavy-ion and pp collisions.

  18. Rf System Requirements for JLab’s MEIC Collider Ring

    SciTech Connect (OSTI)

    Wang, Shaoheng [JLAB; Li, Rui [JLAB; Rimmer, Robert A. [JLAB; Wang, Haipeng [JLAB; Zhang, Yuhong [JLAB

    2013-06-01T23:59:59.000Z

    The Medium-energy Electron Ion Collider (MEIC), proposed by Jefferson Lab, consists of a series of accelerators. At the top energy are the electron and ion collider rings. For the ion ring, it accelerates five long ion bunches to colliding energy and rebunches ions into a train of very short bunches before colliding. A set of low frequency RF system is needed for the long ion bunch energy ramping. Another set of high frequency RF cavities is needed to rebunch ions. For the electron ring, superconducting RF (SRF) cavities are needed to compensate the synchrotron radiation energy loss. The impedance of the SRF cavities must be low enough to keep the high current electron beam stable. The preliminary design requirements of these RF cavities are presented.

  19. Cavity morphology in a Ni based superalloy under heavy ion irradiation with cold pre-injected helium. I

    SciTech Connect (OSTI)

    Zhang, He; Yao, Zhongwen, E-mail: yaoz@me.queensu.ca; Daymond, Mark R. [Department of Mechanical and Materials Engineering, Queen's University Kingston, Ontario K7L 3N6 (Canada); Kirk, Marquis A. [Material Science Division, Argonne National Laboratory Argonne, Illinois 60439 (United States)

    2014-03-14T23:59:59.000Z

    In order to understand radiation damage in the nickel based superalloy Inconel X-750 in thermal reactors, where (n, ?) transmutation reaction also occurred in addition to fast neutron induced atomic displacement, heavy ion (1?MeV Kr{sup 2+}) irradiation with pre-injected helium was performed under in-situ observations of an intermediate voltage electron microscope at Argonne National Laboratory. By comparing to our previous studies using 1?MeV Kr{sup 2+} irradiation solely, the pre-injected helium was found to be essential in cavity nucleation. Cavities started to be visible after Kr{sup 2+} irradiation to 2.7 dpa at ?200?°C in samples containing 200 appm, 1000 appm, and 5000 appm helium, respectively, but not at lower temperatures. The cavity growth was observed during the continuous irradiation. Cavity formation appeared along with a reduced number density of stacking fault tetrahedra, vacancy type defects. With higher pre-injected helium amount, a higher density of smaller cavities was observed. This is considered to be the result of local trapping effect of helium which disperses vacancies. The average cavity size increases with increasing irradiation temperatures; the density reduced; and the distribution of cavities became heterogeneous at elevated temperatures. In contrast to previous characterization of in-reactor neutron irradiated Inconel X-750, no obvious cavity sink to grain boundaries and phase boundaries was found even at high doses and elevated temperatures. MC-type carbides were observed as strong sources for agglomeration of cavities due to their enhanced trapping strength of helium and vacancies.

  20. HEAVY ION COLLISIONS

    E-Print Network [OSTI]

    Siemens, P.J.

    2010-01-01T23:59:59.000Z

    461. 31. M. Sobel, P. Siemens, J. Bondorf and H. A. Bethe,275 (1978) 114. 33. P. J. Siemens and J. 0. Rasvnussen,1976) 1202. 36. P. J. Siemens and J. I. Kapusta, "Evidence

  1. Heavy-ion broad-beam and microprobe studies of single-event upsets in 0.20 um SiGe heterojunction bipolar transistors and circuits.

    SciTech Connect (OSTI)

    Fritz, Karl (Mayo Foundation, Rochester, MN); Irwin, Timothy J. (Jackson & Tull Chartered Engineers, Washington, DC); Niu, Guofu (Auburn University, Auburn, AL); Fodness, Bryan (SGT, Inc., Greenbelt, MD); Carts, Martin A. (Raytheon ITSS, Greenbelt, MD); Marshall, Paul W. (Brookneal, VA); Reed, Robert A. (NASA/GSFC, Greenbelt, MD); Gilbert, Barry (Mayo Foundation, Rochester, MN); Randall, Barbara (Mayo Foundation, Rochester, MN); Prairie, Jason (Mayo Foundation, Rochester, MN); Riggs, Pam (Mayo Foundation, Rochester, MN); Pickel, James C. (PR& T, Inc., Fallbrook, CA); LaBel, Kenneth (NASA/GSFC, Greenbelt, MD); Cressler, John D. (Georgia Institute of Technology, Atlanta, GA); Krithivasan, Ramkumar (Georgia Institute of Technology, Atlanta, GA); Dodd, Paul Emerson; Vizkelethy, Gyorgy

    2003-09-01T23:59:59.000Z

    Combining broad-beam circuit level single-event upset (SEU) response with heavy ion microprobe charge collection measurements on single silicon-germanium heterojunction bipolar transistors improves understanding of the charge collection mechanisms responsible for SEU response of digital SiGe HBT technology. This new understanding of the SEU mechanisms shows that the right rectangular parallele-piped model for the sensitive volume is not applicable to this technology. A new first-order physical model is proposed and calibrated with moderate success.

  2. Dynamical simulation of heavy-ion collisions in the energy range from a few tens MeV/A to a few hundreds MeV/A

    E-Print Network [OSTI]

    M. V. Garzelli

    2008-10-13T23:59:59.000Z

    The overlapping stage of heavy-ion reactions can be simulated by dynamical microscopical models, such as those built on the basis of the Molecular Dynamics (MD) approaches, allowing to study the fragment formation process. The present performances of the Quantum MD (QMD) code developed at the University of Milano are discussed, showing results concerning fragment and particle production at bombarding energies up to $\\lsim$ 700 MeV/A, as well as a preliminary analysis on the isoscaling behaviour of isotopic yield ratios for reactions with isospin composition N/Z in the (1 - 1.2) range, at a 45 MeV/A bombarding energy.

  3. PROCEEDINGS OF THE SECOND WORKSHOP ON EXPERIMENTS AND DETECTORS FOR A RELATIVISTIC HEAVY ION COLLIDER (RHIC), LAWRENCE BERKELEY LABORATORY, MAY 25-29, 1987

    E-Print Network [OSTI]

    Ritter, Hans Georg

    2010-01-01T23:59:59.000Z

    0.1 seconds per track on a VAX 780, approximately linear into approximately 500 x VAX 780 speed (roughly a kiloVAX)coupled by Ethernet to a VAX online computer as. part of its

  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.

    2008-01-01T23:59:59.000Z

    We present the first measurements of the rho(770)(0),K(*)(892),Delta(1232)(++),Sigma(1385), and Lambda(1520) resonances in d+Au collisions at s(NN)=200 GeV, reconstructed via their hadronic decay channels using the STAR detector (the solenoidal...

  5. Studies of heavy ion reactions and transuranic nuclei. Progress report, August 1, 1979-July 31, 1980. [Univ. of Rochester, New York, 8/1/79-7/31/80

    SciTech Connect (OSTI)

    Huizenga, J.R.

    1980-07-01T23:59:59.000Z

    The study of heavy-ion reaction mechanisms at the SuperHILAC and LAMPF is reported. Preprints of five articles and manuscripts of four recent conference papers are given, along with complete citations of publications and a list of personnel. Significant work was performed in the following areas: the bombarding energy dependence of the /sup 209/Bi + /sup 136/Xe reaction; the fragment yields for specific Z and A for projectile-like fragments produced in the reaction of 8.3-MeV/u /sup 56/Fe ions with targets of /sup 56/Fe, /sup 165/Ho, /sup 209/Bi, and /sup 238/U; and time distributions of fragments from delayed fission after muon capture for muonic /sup 235/U, /sup 238/U, /sup 237/Np, /sup 239/Pu, and /sup 242/Pu. (RWR)

  6. Computer Simulation and Comparison of Proton and Carbon Ion Treatment of Tumor Cells Using Particle and Heavy Ion Transport Code System 

    E-Print Network [OSTI]

    Curtis, Keel Brandon

    2011-02-22T23:59:59.000Z

    implemented for treatment in Europe and Japan, this study will focus on carbon as the heavier ion of choice. Comparisons are drawn between moderated and unmoderated protons and carbon ions, all of which have a penetration depth of 10 cm in tissue. Scattering...

  7. Future Electron-Hadron Colliders

    SciTech Connect (OSTI)

    Litvinenko, V.

    2010-05-23T23:59:59.000Z

    Outstanding research potential of electron-hadron colliders (EHC) was clearly demonstrated by first - and the only - electron-proton collider HERA (DESY, Germany). Physics data from HERA revealed new previously unknown facets of Quantum Chromo-Dynamics (QCD). EHC is an ultimate microscope probing QCD in its natural environment, i.e. inside the hadrons. In contrast with hadrons, electrons are elementary particles with known initial state. Hence, scattering electrons from hadrons provides a clearest pass to their secrets. It turns EHC into an ultimate machine for high precision QCD studies and opens access to rich physics with a great discovery potential: solving proton spin puzzle, observing gluon saturation or physics beyond standard model. Access to this physics requires high-energy high-luminosity EHCs and a wide reach in the center-of-mass (CM) energies. This paper gives a brief overview of four proposed electron-hadron colliders: ENC at GSI (Darmstadt, Germany), ELIC/MEIC at TJNAF (Newport News, VA, USA), eRHIC at BNL (Upton, NY, USA) and LHeC at CERN (Geneva, Switzerland). Future electron-hadron colliders promise to deliver very rich physics not only in the quantity but also in the precision. They are aiming at very high luminosity two-to-four orders of magnitude beyond the luminosity demonstrated by the very successful HERA. While ENC and LHeC are on opposite side of the energy spectrum, eRHIC and ELIC are competing for becoming an electron-ion collider (EIC) in the U.S. Administrations of BNL and Jlab, in concert with US DoE office of Nuclear Physics, work on the strategy for down-selecting between eRHIC and ELIC. The ENC, EIC and LHeC QCD physics programs to a large degree are complimentary to each other and to the LHC physics. In last decade, an Electron Ion Collider (EIC) collaboration held about 25 collaboration meetings to develop physics program for EIC with CM energy {approx}100 GeV. One of these meetings was held at GSI, where ENC topic was in the center of discussions. First dedicated LHeC workshop was held in 2008, with a number of dedicated workshops following it. Intense accelerator R&D program is needed to address the challenges posed by the EIC.

  8. Photon collider Higgs factories

    E-Print Network [OSTI]

    V. I. Telnov

    2014-09-19T23:59:59.000Z

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

  9. ION ACCELERATORS AS DRIVERS FOR INERTIAL CONFINEMENT FUSION

    E-Print Network [OSTI]

    Faltens, A.

    2010-01-01T23:59:59.000Z

    and Controlled Nuclear Fusion Research, Brussels, Belgium,of the Heavy Ion Fusion Workshop held at Brookhaven NationalReport, Hearthfire Heavy Ion Fusion, October 1, 1979 - March

  10. Tracks and Voids in Amorphous Ge Induced by Swift Heavy-Ion Irradiation M. C. Ridgway,1,* T. Bierschenk,1

    E-Print Network [OSTI]

    Nordlund, Kai

    displacements at much lower energies are negli- gible in the SHII regime. The efficiency with which energy 0200, Australia 2 Australian Synchrotron, Clayton 3168, Australia 3 Department of Physics and Helsinki of ion- solid interactions at very high ion energies remains poorly understood. Such interactions

  11. Parametic Study of the current limit within a single driver-scaletransport beam line of an induction Linac for Heavy Ion Fusion

    SciTech Connect (OSTI)

    Prost, Lionel Robert

    2007-02-14T23:59:59.000Z

    The High Current Experiment (HCX) at Lawrence Berkeley National Laboratory is part of the US program that explores heavy-ion beam as the driver option for fusion energy production in an Inertial Fusion Energy (IFE) plant. The HCX is a beam transport experiment at a scale representative of the low-energy end of an induction linear accelerator driver. The primary mission of this experiment is to investigate aperture fill factors acceptable for the transport of space-charge-dominated heavy-ion beams at high intensity (line charge density {approx}0.2 {micro}C/m) over long pulse durations (4 {micro}s) in alternating gradient focusing lattices of electrostatic or magnetic quadrupoles. This experiment is testing transport issues resulting from nonlinear space-charge effects and collective modes, beam centroid alignment and steering, envelope matching, image charges and focusing field nonlinearities, halo and, electron and gas cloud effects. We present the results for a coasting 1 MeV K{sup +} ion beam transported through ten electrostatic quadrupoles. The measurements cover two different fill factor studies (60% and 80% of the clear aperture radius) for which the transverse phase-space of the beam was characterized in detail, along with beam energy measurements and the first halo measurements. Electrostatic quadrupole transport at high beam fill factor ({approx}80%) is achieved with acceptable emittance growth and beam loss. We achieved good envelope control, and re-matching may only be needed every ten lattice periods (at 80% fill factor) in a longer lattice of similar design. We also show that understanding and controlling the time dependence of the envelope parameters is critical to achieving high fill factors, notably because of the injector and matching section dynamics.

  12. 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.

    2008-01-01T23:59:59.000Z

    detector at Brookhaven National Laboratory during the 2001 run. Gold nuclei were collided at ?sNN = 200 GeV and the charged particle tracks were reconstructed in a cylindrical TimeProjectionChamber (TPC) [19]. TheTPC is a 4.2-m-long barrel with a 2-m... 150 200 250 300 350 400 FIG. 8. Projections of the two-dimensional efficiency-corrected #7;h vs cos( h) distributions obtained with the minimum bias data set. The solid line shows the result of the two-dimensional fit to the data with Eq. (6...

  13. Intense ion beam propagation in a reactor sized chamber

    E-Print Network [OSTI]

    Vay, J.L.; Deutsch, C.

    2000-01-01T23:59:59.000Z

    beams in a heavy ion fusion reactor chamber filled with lowIon Fusion, Intense Ion Beams, Reaction Chamber. P.A.C.S.heavy ion beam propagation in the reaction chamber, Fus.

  14. SOURCE REGIONS OF THE INTERPLANETARY MAGNETIC FIELD AND VARIABILITY IN HEAVY-ION ELEMENTAL COMPOSITION IN GRADUAL SOLAR ENERGETIC PARTICLE EVENTS

    SciTech Connect (OSTI)

    Ko, Yuan-Kuen; Wang, Yi-Ming [Space Science Division, Naval Research Laboratory, Code 7680, Washington, DC 20375 (United States); Tylka, Allan J. [NASA Goddard Space Flight Center, Code 672, Greenbelt, MD 20771 (United States); Ng, Chee K. [College of Science, George Mason University, Fairfax, VA 22030 (United States); Dietrich, William F., E-mail: yko@ssd5.nrl.navy.mil [Praxis, Inc., Alexandria, VA 22303 (United States)

    2013-10-20T23:59:59.000Z

    Gradual solar energetic particle (SEP) events are those in which ions are accelerated to their observed energies by interactions with a shock driven by a fast coronal mass ejection (CME). Previous studies have shown that much of the observed event-to-event variability can be understood in terms of shock speed and evolution in the shock-normal angle. However, an equally important factor, particularly for the elemental composition, is the origin of the suprathermal seed particles upon which the shock acts. To tackle this issue, we (1) use observed solar-wind speed, magnetograms, and the potential-field source-surface model to map the Sun-L1 interplanetary magnetic field (IMF) line back to its source region on the Sun at the time of the SEP observations and (2) then look for a correlation between SEP composition (as measured by Wind and Advanced Composition Explorer at ?2-30 MeV nucleon{sup –1}) and characteristics of the identified IMF source regions. The study is based on 24 SEP events, identified as a statistically significant increase in ?20 MeV protons and occurring in 1998 and 2003-2006, when the rate of newly emergent solar magnetic flux and CMEs was lower than in solar-maximum years, and the field-line tracing is therefore more likely to be successful. We find that the gradual SEP Fe/O is correlated with the field strength at the IMF source, with the largest enhancements occurring when the footpoint field is strong due to the nearby presence of an active region (AR). In these cases, other elemental ratios show a strong charge-to-mass (q/M) ordering (at least on average), similar to that found in impulsive events. Such results lead us to suggest that magnetic reconnection in footpoint regions near ARs bias the heavy-ion composition of suprathermal seed ions by processes qualitatively similar to those that produce larger heavy-ion enhancements in impulsive SEP events. To address potential technical concerns about our analysis, we also discuss efforts to exclude impulsive SEP events from our event sample.

  15. Role of Anharmonic Vibration on Heavy-ion Fusion Reaction and Large Angle Quasi-elastic Scattering of {sup 16}O+{sup 144}Sm

    SciTech Connect (OSTI)

    Muhammad, Zamrun F. [Jurusan Fisika, FMIPA Universitas Haluoleo, Kendari, Sulawesi Tenggara, 93232 (Indonesia); Hagino, K. [Department of Physics, Tohoku University, Sendai, 980-8576 (Japan)

    2009-07-10T23:59:59.000Z

    We study the effects of double quadrupole and octupole phonon excitations of {sup 144}Sm nucleus on heavy-ion fusion reaction and large angle quasi-elastic scattering for {sup 16}O+{sup 144}Sm reaction using the coupled-channels approach. We explicitly taken into account the anharmonicites of nuclear vibrations using the sdf-interacting boson model. It is shown that the anhamronicities play an essential role in reproducing the experimental data of the fusion cross section as well as the fusion barrier distribution for this system. Also the quasi-elastic cross section is well reproduced in this way. However, the quasi-elastic barrier distribution has a high distinct peak which is smeared out in the experimental data. Our study indicates that the fusion and quasi-elastic barrier distribution for {sup 16}O+{sup 144}Sm system cannot be accounted for simultaneously with the standard coupled-channels formalism.

  16. The impact of energy conservation in transport models on the $\\pi^-/\\pi^+$ multiplicity ratio in heavy-ion collisions and the symmetry energy

    E-Print Network [OSTI]

    Cozma, M D

    2014-01-01T23:59:59.000Z

    The charged pion multiplicity ratio in intermediate energy central heavy-ion collisions has been proposed as a suitable observable to constrain the high density dependence of the isovector part of the equation of state, with contradicting results. Using an upgraded version of the T\\"ubingen QMD transport model, which allows the conservation of energy at a local or global level by accounting for the potential energy of hadrons in two-body collisions and leading thus to particle production threshold shifts, we demonstrate that compatible constraints for the symmetry energy stiffness can be extracted from pion multiplicity and elliptic flow observables. Nevertheless, pion multiplicities are proven to be highly sensitive to the yet unknown isovector part of the in-medium $\\Delta$(1232) potential which hinders presently the extraction of meaningful information on the high density dependence of the symmetry energy. A solution to this problem together with the inclusion of contributions presently neglected, such as ...

  17. Event-by-event fluctuations in perturbative QCD + saturation + hydro model: pinning down QCD matter shear viscosity in ultrarelativistic heavy-ion collisions

    E-Print Network [OSTI]

    Niemi, H; Paatelainen, R

    2015-01-01T23:59:59.000Z

    We introduce an event-by-event perturbative-QCD + saturation + hydro ("EKRT") framework for ultrarelativistic heavy-ion collisions, where we compute the produced fluctuating QCD-matter energy densities from next-to-leading order perturbative QCD using a saturation conjecture to control soft particle production, and describe the space-time evolution of the QCD matter with dissipative fluid dynamics, event by event. We perform a simultaneous comparison of the centrality dependence of hadronic multiplicities, transverse momentum spectra, and flow coefficients of the azimuth-angle asymmetries, against the LHC and RHIC measurements. We compare also the computed event-by-event probability distributions of relative fluctuations of elliptic flow, and event-plane angle correlations, with the experimental data from Pb+Pb collisions at the LHC. We show how such a systematic multi-energy and multi-observable analysis tests the initial state calculation and the applicability region of hydrodynamics, and in particular how ...

  18. Semi-classical Characters and Optical Model Description of Heavy Ion Scattering, Direct Reactions, and Fusion at Near-barrier Energies

    E-Print Network [OSTI]

    B. T. Kim; W. Y. So; S. W. Hong; T. Udagawa

    2001-11-02T23:59:59.000Z

    An approach is proposed to calculate the direct reaction (DR) and fusion probabilities for heavy ion collisions at near-Coulomb-barrier energies as functions of the distance of closest approach D within the framework of the optical model that introduces two types of imaginary potentials, DR and fusion. The probabilities are calculated by using partial DR and fusion cross sections, together with the classical relations associated with the Coulomb trajectory. Such an approach makes it possible to analyze the data for angular distributions of the inclusive DR cross section, facilitating the determination of the radius parameters of the imaginary DR potential in a less ambiguous manner. Simultaneous $\\chi^{2}$-analyses are performed of relevant data for the $^{16}$O+$^{208}$Pb system near the Coulomb-barrier energy.

  19. A new scheme of causal viscous hydrodynamics for relativistic heavy-ion collisions: A Riemann solver for quark–gluon plasma

    SciTech Connect (OSTI)

    Akamatsu, Yukinao, E-mail: akamatsu@kmi.nagoya-u.ac.jp [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan)] [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan); Inutsuka, Shu-ichiro [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan)] [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Nonaka, Chiho [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan) [Kobayashi–Maskawa Institute for the Origin of Particles and the Universe (KMI), Nagoya University, Nagoya 464-8602 (Japan); Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Takamoto, Makoto [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan) [Department of Physics, Nagoya University, Nagoya 464-8602 (Japan); Max-Planck-Institut für Kernphysik, Postfach 103980, 69029 Heidelberg (Germany)

    2014-01-01T23:59:59.000Z

    In this article, we present a state-of-the-art algorithm for solving the relativistic viscous hydrodynamics equation with the QCD equation of state. The numerical method is based on the second-order Godunov method and has less numerical dissipation, which is crucial in describing of quark–gluon plasma in high-energy heavy-ion collisions. We apply the algorithm to several numerical test problems such as sound wave propagation, shock tube and blast wave problems. In sound wave propagation, the intrinsic numerical viscosity is measured and its explicit expression is shown, which is the second-order of spatial resolution both in the presence and absence of physical viscosity. The expression of the numerical viscosity can be used to determine the maximum cell size in order to accurately measure the effect of physical viscosity in the numerical simulation.

  20. JOURNAL DE PHYSIQUE Colloque C6, suppl&mentau no 11-12, Tome 32, Novembre-Dkcembre 1971, page C6-265 HEAVY ION REACTION CHANNELS DETERMINED

    E-Print Network [OSTI]

    Boyer, Edmond

    sections for different reaction channels. The radioactive products were identified by half-life, gamma-ray-life for the radioactivity was used along with the gamma ray energies and (*) Research sponsored by the U. S. Atomic Energy. - Gamma-ray measurements following heavy ion bombardment were used to determine the absolute cross

  1. ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

    SciTech Connect (OSTI)

    ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; ET AL.

    2005-02-28T23:59:59.000Z

    This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linac. The highly successful development of an EBIS at BNL now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based pre-injectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

  2. Computer Simulation and Comparison of Proton and Carbon Ion Treatment of Tumor Cells Using Particle and Heavy Ion Transport Code System

    E-Print Network [OSTI]

    Curtis, Keel Brandon

    2011-02-22T23:59:59.000Z

    photons, positively charged protons primarily slow down through many Coulomb interactions with the positive nuclei and negative electrons comprising a target material. (Attix 2004) Each interaction transfers a small amount of energy from the incident... and repair, while cancer cells are more likely to try and grow with damaged DNA. These cells are more likely to experience cell death or an inability to continue growth and division. (Pawlik and Keyomarsi 2004) 1.2 Carbon Ions As shown in Fig. 1...

  3. Correlation between balance energy and transition energy for symmetric colliding nuclei

    SciTech Connect (OSTI)

    Rajni,; Kumar, Suneel; Puri, Rajeev K. [School of Physics and Materials Science, Thapar University, Patiala-147004, Punjab (India); Department of Physics, Panjab University, Chandigarh-160014 (India)

    2011-09-15T23:59:59.000Z

    We study the correlation between balance energy and transition energy of fragments in heavy-ion collisions for different systems at incident energies between 40 and 1200 MeV/nucleon using an isospin-dependent quantum molecular dynamics model. With increasing incident energy, the elliptic flow shows a transition from positive (in-plane) to negative (out-of-plane) flow. This transition energy is found to depend on the size of the fragments, composite mass of the reacting system, and the impact parameter of the reaction. It has been observed that a reduced cross section can explain the experimental data. There is a correlation between transition energy and balance energy as their difference decreases with an increase in the total mass of colliding nuclei.

  4. Correlation between balance energy and transition energy for symmetric colliding nuclei

    E-Print Network [OSTI]

    Rajni; Suneel Kumar; Rajeev K. Puri

    2011-10-04T23:59:59.000Z

    We study the correlation between balance energy and transition energy of fragment in heavy-ion collisions for different systems at incident energies between 40 and 1200 MeV/nucleon using an isospin-dependent quantum molecular dynamics model. With increasing incident energy, the elliptic flow shows a transition from positive (in-plane) to negative (out-of-plane) flow. This transition energy is found to depend on the size of fragments, composite mass of reacting system, and the impact parameter of reaction. It has been observed that reduced cross-section can explain the experimental data. There is a correlation between transition energy and balance energy as their difference decreases with increase in the total mass of colliding nuclei.

  5. ELECTRON BEAM ION SOURCE PREINJECTOR PROJECT (EBIS) CONCEPTUAL DESIGN REPORT.

    SciTech Connect (OSTI)

    ALESSI, J.; BARTON, D.; BEEBE, E.; GASSNER, D.; GRANDINETTI, R.; HSEUH, H.; JAVIDFAR, A.; KPONOU, A.; LAMBIASE, R.; LESSARD, E.; LOCKEY, R.; LODESTRO, V.; MAPES, M.; MIRABELLA, D.; NEHRING, T.; OERTER, B.; PENDZICK, A.; PIKIN, A.; RAPARIA, D.; RITTER, J.; ROSER, T.; RUSSO, T.; SNYDSTRUP, L.; WILINSKI, M.; ZALTSMAN, A.; ZHANG, S.

    2005-09-01T23:59:59.000Z

    This report describes a new heavy ion pre-injector for the Relativistic Heavy Ion Collider (RHIC) based on a high charge state Electron Beam Ion Source (EBIS), a Radio Frequency Quadrupole (RFQ) accelerator, and a short Linear accelerator (Linac). The highly successful development of an EBIS at Brookhaven National Laboratory (BNL) now makes it possible to replace the present pre-injector that is based on an electrostatic Tandem with a reliable, low maintenance Linac-based pre-injector. Linac-based preinjectors are presently used at most accelerator and collider facilities with the exception of RHIC, where the required gold beam intensities could only be met with a Tandem until the recent EBIS development. EBIS produces high charge state ions directly, eliminating the need for the two stripping foils presently used with the Tandem. Unstable stripping efficiencies of these foils are a significant source of luminosity degradation in RHIC. The high reliability and flexibility of the new Linac-based pre-injector will lead to increased integrated luminosity at RHIC and is an essential component for the long-term success of the RHIC facility. This new pre-injector, based on an EBIS, also has the potential for significant future intensity increases and can produce heavy ion beams of all species including uranium beams and, as part of a future upgrade, might also be used to produce polarized {sup 3}He beams. These capabilities will be critical to the future luminosity upgrades and electron-ion collisions in RHIC. The proposed pre-injector system would also provide for a major enhancement in capability for the NASA Space Radiation Laboratory (NSRL), which utilizes heavy-ion beams from the RHIC complex. EBIS would allow for the acceleration of all important ion species for the NASA radiobiology program, such as, helium, argon, and neon which are unavailable with the present Tandem injector. In addition, the new system would allow for very rapid switching of ion species for NSRL experiments, reducing delays due to the interference with RHIC injection operations, and allowing enhanced mixed field radiation studies. The new RFQ and Linac that are used to accelerate beams from the EBIS to an energy sufficient for injection into the Booster are both very similar to existing devices already in operation at other facilities. Injection into the Booster will occur at the same location as the existing injection from the Tandem.

  6. acid-sensing ion channel-1b: Topics by E-print Network

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

    of mTORC1 In the m Sabatini, David M. 2 Ion Colliders CERN Preprints Summary: High-energy ion colliders are large research tools in nuclear physics to study the...

  7. Fusion-fission and quasifission in the reactions with heavy ions leading to the formation of Hs

    SciTech Connect (OSTI)

    Itkis, I. M.; Itkis, M. G.; Knyazheva, G. N.; Kozulin, E. M. [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation)

    2012-10-20T23:59:59.000Z

    Mass and energy distributions of binary reaction products obtained in the reactions {sup 22}Ne+{sup 249}Cf,{sup 26}Mg+{sup 248}Cm,{sup 36}S+{sup 238}U and {sup 58}Fe+{sup 208}Pb leading to Hs isotopes have been measured. At energies below the Coulomb barrier the bimodal fission of Hs*, formed in the reaction {sup 26}Mg+{sup 248}Cm, is observed. In the reaction {sup 36}S+{sup 238}U the considerable part of the symmetric fragments arises from the quasifission process. At energies above the Coulomb barrier the symmetric fragments originate mainly from fusion-fission process for both reactions with Mg and S ions. In the case of the {sup 58}Fe+{sup 208}Pb reaction the quasifission process dominates at all measured energies. The pre- and post-scission neutron multiplicities as a function of the fragment mass have been obtained for the reactions studied.

  8. Stability of nanoclusters in 14YWT oxide dispersion strengthened steel under heavy ion-irradiation by atom probe tomography

    SciTech Connect (OSTI)

    Jianchao He; Farong Wan; Kumar Sridharan; Todd R. Allen; A. Certain; V. Shutthanandan; Y.Q. Wu

    2014-12-01T23:59:59.000Z

    14YWT oxide dispersion strengthened (ODS) ferritic steel was irradiated with of 5 MeV Ni2+ ions, at 300 C, 450 C, and 600 C to a damage level of 100 dpa. The stability of Ti–Y–O nanoclusters was investigated by applying atom probe tomography (APT) in voltage mode, of the samples before and after irradiations. The average size and number density of the nanoclusters was determined using the maximum separation method. These techniques allowed for the imaging of nanoclusters to sizes well below the resolution limit of conventional transmission electron microscopy techniques. The most significant changes were observed for samples irradiated at 300 C where the size (average Guinier radius) and number density of nanoclusters were observed to decrease from 1.1 nm to 0.8 nm and 12 1023 to 3.6 1023, respectively. In this study, the nanoclusters are more stable at higher temperature.

  9. Stability Of Nanoclusters In 14YWT Oxide Dispersion Strengthened Steel Under Heavy Ion-irradiation By Atom Probe Tomography

    SciTech Connect (OSTI)

    He, Jianchao; Wan, F.; Sridharan, Kumar; Allen, Todd R.; Certain, Alicia G.; Shutthanandan, V.; Wu, Yaqiao

    2014-12-01T23:59:59.000Z

    14YWT oxide dispersion strengthened (ODS) ferritic steel was irradiated with of 5 MeV Ni2+ ions, at 300 °C, 450 °C, and 600 °C to a damage level of 100 dpa. The stability of Ti–Y–O nanoclusters was investigated by applying atom probe tomography (APT) in voltage mode, of the samples before and after irradiations. The average size and number density of the nanoclusters was determined using the maximum separation method. These techniques allowed for the imaging of nanoclusters to sizes well below the resolution limit of conventional transmission electron microscopy techniques. The most significant changes were observed for samples irradiated at 300 °C where the size (average Guinier radius) and number density of nanoclusters were observed to decrease from 1.1 nm to 0.8 nm and 12 × 1023 to 3.6 × 1023, respectively. In this study, the nanoclusters are more stable at higher temperature.

  10. Fission and quasifission modes in heavy-ion-induced reactions leading to the formation of Hs{sup *}

    SciTech Connect (OSTI)

    Itkis, I. M.; Kozulin, E. M.; Itkis, M. G.; Knyazheva, G. N.; Bogachev, A. A.; Chernysheva, E. V.; Krupa, L.; Oganessian, Yu. Ts.; Zagrebaev, V. I.; Rusanov, A. Ya.; Goennenwein, F.; Dorvaux, O.; Stuttge, L.; Hanappe, F.; Vardaci, E.; Goes Brennand, E. de [Flerov Laboratory of Nuclear Reactions, Joint Institute for Nuclear Research, 141980 Dubna (Russian Federation); Institute of Nuclear Physics of the National Nuclear Center of Kazakhstan, 050032 Almaty (Kazakhstan); Physikalisches Institut, Universitaet Tuebingen, D-72076 Tuebingen (Germany); Institut Pluridisciplinaire Hubert Curien and Universite de Strasbourg, F-67037 Strasbourg (France); Universite Libre de Bruxelles, CP229, B-1050 Bruxelles, Belgique (Belgium); Istituto Nazionale di Fisica Nucleare and Dipartimento di Scienze Fisiche dell'Universita di Napoli, Napoli (Italy); Departamento de Fisica, Universidade Estadual da Paraiba, 58109-753 Campina Grande (Brazil)

    2011-06-15T23:59:59.000Z

    Mass and energy distributions of binary reaction products obtained in the reactions {sup 22}Ne+{sup 249}Cf,{sup 26}Mg+{sup 248}Cm, {sup 36}S+{sup 238}U, and {sup 58}Fe+{sup 208}Pb have been measured. All reactions lead to Hs isotopes. At energies below the Coulomb barrier the bimodal fission of Hs{sup *}, formed in the reaction {sup 26}Mg+{sup 248}Cm, is observed. In the reaction {sup 36}S+{sup 238}U, leading to the formation of a similar compound nucleus, the main part of the symmetric fragments arises from the quasifission process. At energies above the Coulomb barrier fusion-fission is the main process leading to the formation of symmetric fragments for both reactions with Mg and S ions. In the case of the {sup 58}Fe+{sup 208}Pb reaction the quasifission process dominates at all measured energies.

  11. Commentary on A Conceptual Design of Transport Lines for a Heavy-Ion Inertial-Fusion Power Plant

    SciTech Connect (OSTI)

    Lee, E.P.

    2011-04-13T23:59:59.000Z

    Some major system features are not stated but can be inferred. For example this is probably an engineering test facility, not a power plant driver, because the standoff from target to final magnet is only 5.0 m. The fusion target takes two-sided illumination with indirect drive using a total of 60 beam pulses: 10 pre-pulses (3.0 GeV) + 20 main pulses (4.0 GeV) from each side. On page 12 it's stated that the charge per beam pulse is 26.8 {micro}C, so we calculate pre-pulse: 20 x 3 GeV x 26.8 {micro}C = 1.608MJ, main pulse: 40 x 4 GeV x 26.8 {micro}C = 4.288MJ, total beam energy 5.896MJ. The beam ion mass ks 200 amu, so the species is Hg{sup +}. Therefore the mid-pulse velocities are: pre-pulse v = .1773c = 5.316 x 10{sup 7} m/s, main pulse v = .2040c = 6.114 x 10{sup 7} m/s, On page 12 it is stated that the pre-compression pulse length is L{sub 0} = 10.0m, and compression is by a 'factor of order 20'. They infer a final pulse length of about .5 m and final durations pre-pulse {tau} {approx} .5/5.316 x 10{sup 7} = 9.4 ns; main pulse {tau} {approx} .5/6.114 x 10{sup 7} = 8.2 ms. The magnetic rigidity of the beam ions is [B{rho}] = {gamma}m v/e = {l_brace} 112.0 T-m - prepulse/129.5 T-m - mainpulse{r_brace}.

  12. The impact of energy conservation in transport models on the $?^-/?^+$ multiplicity ratio in heavy-ion collisions and the symmetry energy

    E-Print Network [OSTI]

    M. D. Cozma

    2014-09-10T23:59:59.000Z

    The charged pion multiplicity ratio in intermediate energy central heavy-ion collisions has been proposed as a suitable observable to constrain the high density dependence of the isovector part of the equation of state, with contradicting results. Using an upgraded version of the T\\"ubingen QMD transport model, which allows the conservation of energy at a local or global level by accounting for the potential energy of hadrons in two-body collisions and leading thus to particle production threshold shifts, we demonstrate that compatible constraints for the symmetry energy stiffness can be extracted from pion multiplicity and elliptic flow observables. Nevertheless, pion multiplicities are proven to be highly sensitive to the yet unknown isovector part of the in-medium $\\Delta$(1232) potential which hinders presently the extraction of meaningful information on the high density dependence of the symmetry energy. A solution to this problem together with the inclusion of contributions presently neglected, such as in-medium pion potentials and retardation effects, are needed for a final verdict on this topic.

  13. Event-by-event fluctuations in perturbative QCD + saturation + hydro model: pinning down QCD matter shear viscosity in ultrarelativistic heavy-ion collisions

    E-Print Network [OSTI]

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

    2015-05-11T23:59:59.000Z

    We introduce an event-by-event perturbative-QCD + saturation + hydro ("EKRT") framework for ultrarelativistic heavy-ion collisions, where we compute the produced fluctuating QCD-matter energy densities from next-to-leading order perturbative QCD using a saturation conjecture to control soft particle production, and describe the space-time evolution of the QCD matter with dissipative fluid dynamics, event by event. We perform a simultaneous comparison of the centrality dependence of hadronic multiplicities, transverse momentum spectra, and flow coefficients of the azimuth-angle asymmetries, against the LHC and RHIC measurements. We compare also the computed event-by-event probability distributions of relative fluctuations of elliptic flow, and event-plane angle correlations, with the experimental data from Pb+Pb collisions at the LHC. We show how such a systematic multi-energy and multi-observable analysis tests the initial state calculation and the applicability region of hydrodynamics, and in particular how it constrains the temperature dependence of the shear viscosity-to-entropy ratio of QCD matter in its different phases in a remarkably consistent manner.

  14. 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

    2012-09-03T23:59:59.000Z

    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 $\\sqrt{s_{NN}}$.

  15. The Electron-Ion Collider Science Case

    E-Print Network [OSTI]

    Richard G. Milner

    2014-05-27T23:59:59.000Z

    For the first time, physicists are in the position to precisely study a fully relativistic quantum field theory: Quantum ChromoDynamics (QCD). QCD is a central element of the Standard Model and provides the theoretical framework for understanding the strong interaction. This demands a powerful new electron microscope to probe the virtual particles of QCD. Ab initio calculations using lattice gauge theory on the world's most powerful supercomputers are essential for comparison with the data. The new accelerator and computing techniques demand aggressive development of challenging, innovative technologies.

  16. Photon collider at TESLA

    E-Print Network [OSTI]

    Valery Telnov

    2001-03-06T23:59:59.000Z

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

  17. The International Linear Collider

    E-Print Network [OSTI]

    Barish, Barry

    2013-01-01T23:59:59.000Z

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

  18. HEAVY-ION FRACTIONATION IN THE IMPULSIVE SOLAR ENERGETIC PARTICLE EVENT OF 2002 AUGUST 20: ELEMENTS, ISOTOPES, AND INFERRED CHARGE STATES

    SciTech Connect (OSTI)

    Wiedenbeck, M. E. [Jet Propulsion Laboratory, California Institute of Technology, Pasadena, CA 91109 (United States); Cohen, C. M. S.; Leske, R. A.; Mewaldt, R. A.; Cummings, A. C.; Stone, E. C. [California Institute of Technology, Pasadena, CA 91125 (United States); Von Rosenvinge, T. T., E-mail: mark.e.wiedenbeck@jpl.nasa.go [NASA Goddard Space Flight Center, Greenbelt, MD 20771 (United States)

    2010-08-20T23:59:59.000Z

    Measurements of heavy-ion elemental and isotopic composition in the energy range {approx}12-60 MeV nucleon{sup -1} are reported from the Advanced Composition Explorer/Solar Isotope Spectrometer (ACE/SIS) instrument for the solar energetic particle (SEP) event of 2002 August 20. We investigate fractionation in this particularly intense impulsive event by examining the enhancements of elemental and isotopic abundance ratios relative to corresponding values in the solar wind. The elemental enhancement pattern is similar to those in other impulsive events detected by ACE/SIS and in compilations of average impulsive-event composition. For individual elements, the abundance of a heavy isotope (mass M {sub 2}) is enhanced relative to that of a lighter isotope (M{sub 1}) by a factor {approx}(M {sub 1}/M {sub 2}){sup {alpha}} with {alpha} {approx_equal} -15. Previous studies have reported elemental abundance enhancements organized as a power law in Q/M, the ratio of estimated ionic charge to mass in the material being fractionated. We consider the possibility that a fractionation law of this form could be responsible for the isotopic fractionation as a power law in the mass ratio and then explore the implications it would have for the ionic charge states in the source material. Assuming that carbon is fully stripped (Q{sub C} = 6), we infer mean values of the ionic charge during the fractionation process, Q{sub Z} , for a variety of elements with atomic numbers 7 {<=} Z {<=} 28. We find that Q{sub Fe} {approx_equal} 21-22, comparable to the highest observed values that have been reported at lower energies in impulsive SEP events from direct measurements near 1 AU. The inferred charge states as a function of Z are characterized by several step increases in the number of attached electrons, Z - Q{sub Z} . We discuss how this step structure, together with the known masses of the elements, might account for a variety of features in the observed pattern of elemental abundance enhancements. We also briefly consider alternative fractionation laws and the relationship between the charge states we infer in the source material and those derived from in situ observations.

  19. Results from a Prototype MAPS Sensor Telescope and Readout Systemwith Zero Suppression for the Heavy Flavor Tracker at STAR

    SciTech Connect (OSTI)

    Greiner, Leo C.; Matis, Howard S.; Ritter, Hans G.; Rose, AndrewA.; Stezelberger, Thorsten; Sun, Xiangming; Szelezniak, Michal A.; Thomas, James H.; Vu, Chinh Q.; Wieman, Howard H.

    2008-02-11T23:59:59.000Z

    We describe a three Mimostar-2 Monolithic Active PixelSensor (MAPS) sensor telescope prototype with an accompanying readoutsystem incorporating on-the-fly data sparsification. The system has beencharacterized and we report on the measured performance of the sensortelescope and readout system in beam tests conducted both at the AdvancedLight Source (ALS) at Lawrence Berkeley National Laboratory (LBNL) and inthe STAR experiment at the Relativistic Heavy Ion Collider (RHIC). Thiseffort is part of the development and prototyping work that will lead toa vertex detector for the STAR experiment.

  20. Interpenetration and stagnation in colliding laser plasmas

    SciTech Connect (OSTI)

    Al-Shboul, K. F. [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States) [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Department of Nuclear Engineering, Jordan University of Science and Technology, Irbid 22110 (Jordan); Harilal, S. S., E-mail: hari@purdue.edu; Hassan, S. M.; Hassanein, A. [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States)] [Center for Materials Under eXtreme Environment, School of Nuclear Engineering, Purdue University, West Lafayette, Indiana 47907 (United States); Costello, J. T. [School of Physical Sciences and NCPST, Dublin City University, Dublin 9 (Ireland)] [School of Physical Sciences and NCPST, Dublin City University, Dublin 9 (Ireland); Yabuuchi, T.; Tanaka, K. A. [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 5650871 (Japan)] [Graduate School of Engineering, Osaka University, Yamada-oka 2-1, Suita, Osaka 5650871 (Japan); Hirooka, Y. [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu (Japan)] [National Institute for Fusion Science, 322-6 Oroshi, Toki, Gifu (Japan)

    2014-01-15T23:59:59.000Z

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