The Experts below are selected from a list of 297 Experts worldwide ranked by ideXlab platform
Dennis Perepelitsa - One of the best experts on this subject based on the ideXlab platform.
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reconstructed jet results in p p d au and cu cu collisions at 200 gev from phenix
Nuclear Physics, 2013Co-Authors: Dennis PerepelitsaAbstract:Abstract Jet reconstruction in heavy ion collisions at RHIC and the LHC is becoming a popular tool to explore medium effects including the energy loss and modified fragmentation of hard-scattered Partons. In p + A and d + A collisions, reconstructed jets are important for evaluating cold nuclear matter effects such as the impact parameter dependence of nuclear parton distribution functions and initial state energy loss. We present current PHENIX results from p + p, d + Au, and Cu + Cu collisions at 200 GeV using the Gaussian filter and anti- k T algorithms. The systematic study of direct jet reconstruction across a variety of collisions systems at PHENIX will help to tell a coherent story of jet physics at RHIC.
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exploring cold nuclear matter effects in d au with high pt reconstructed jets at phenix
Nuclear Physics, 2013Co-Authors: Dennis PerepelitsaAbstract:Proton–nucleus (p + A) collisions can be used to investigate cold nuclear matter effects on hard-scattered Partons and serve as an important baseline for heavy–ion collisions. In particular, p + A collisions at different centrality selections can probe the impact parameter dependence of nuclear parton distribution functions, initial state energy loss and final state parton interactions in the cold nucleus. Jet reconstruction can better determine the initial parton kinematics and recent improvements in analysis techniques allow the exploration of these effects over a wide pT range. We present the latest jet reconstruction measurements performed with the PHENIX detector at RHIC in deuteron–gold (d + Au) collisions at 200 GeV using the Gaussian filter algorithm and discuss the possible implications on descriptions of cold nuclear matter.
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reconstructed jet results in p p d au and cu cu collisions at 200 gev from phenix
Journal of Physics: Conference Series, 2012Co-Authors: Dennis PerepelitsaAbstract:Jet reconstruction in heavy ion collisions at RHIC and the LHC is becoming a popular tool for exploring medium effects including the energy loss and modified fragmentation of hard-scattered Partons. In p+A and d+A collisions, reconstructed jets are important for evaluating cold nuclear matter effects such as the impact parameter dependence of nuclear parton distribution functions and initial state energy loss. We present current PHENIX results from p+p, d+Au, and Cu+Cu collisions at 200 GeV using the Gaussian filter and anti-kT algorithms. The systematic study of direct jet reconstruction across a variety of collisions systems at PHENIX will help to tell a coherent story of jet physics at RHIC.
Joseph I Kapusta - One of the best experts on this subject based on the ideXlab platform.
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chemical equilibration of Partons in high energy heavy ion collisions
Physical Review D, 1993Co-Authors: Klaus Geiger, Joseph I KapustaAbstract:The chemical composition of the hot and dense parton matter formed in the central region of ultrarelativistic heavy-ion collisions is studied for the case of Au+Au collisions at energies reached at the BNL RHIC using the parton cascade model. It is shown that within this framework, which is based on current understanding of semihard and hard interactions in QCD including the emission and absorption of soft Partons, a chemical equilibration between the gluons and the quarks cannot be achieved. The gluons and [ital u], [ital d], [ital s], and [ital c] quarks all rapidly approach kinetic equilibrium with a common temperature. The gluons subsequently also achieve chemical equilibrium, but the light quarks only reach about 60% of their ideal chemical equilibrium densities. It is demonstrated that the baryon density in the central region is small relative to the total parton density, with an associated ratio of baryon chemical potential to temperature of 0.35, slowly decreasing with time. The implications of the formation of such a hot, gluon-dominated plasma for strangeness, charm, and dilepton production are discussed.
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dilepton radiation from cascading Partons in ultrarelativistic nuclear collisions
Physical Review Letters, 1993Co-Authors: Klaus Geiger, Joseph I KapustaAbstract:We compute the radiation of lepton pairs by the quarks during a central collision between gold nuclei at energy of the Brookhaven Relativistic Heavy Ion Collider ([radical][ital s] =200[ital A] GeV) within the parton cascade model. The distribution of radiated pairs evolves smoothly from the initial Drell-Yan type reactions all the way towards equilibrium radiation. Contributions from reactions involving secondary Partons dominate the Drell-Yan yield by at least a factor of 5 even at an invariant mass of 8 GeV. Therefore, experiments can test the evolution of Partons towards thermal equilibrium at these energies.
Dinesh K. Srivastava - One of the best experts on this subject based on the ideXlab platform.
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medium modification of charm production in relativistic heavy ion collisions due to pre equilibrium dynamics of Partons at sqrt s_ textrm nn 0 2 5 02 tev
arXiv: Nuclear Theory, 2019Co-Authors: Dinesh K. Srivastava, Rupa ChatterjeeAbstract:We study the production dynamics of charm quarks in the parton cascade model for relativistic heavy ion collisions at RHIC and LHC energies. The model is eminently suited for a study of the pre-equilibrium dynamics of charm quarks at modest transverse momenta. The treatment is motivated by QCD parton picture and describes the dynamics of an ultra-relativistic heavy-ion collision in terms of cascading Partons which undergo scattering and multiplication while propagating. We find considerable suppression of charm quarks production in $AA$ collisions compared to those for $pp$ collisions at the same $\sqrt{s_{\text {NN}}}$ scaled by number of collisions. This may be important for an accurate determination of energy loss suffered by charm quarks while traversing the thermalized quark gluon plasma.
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light from cascading Partons in relativistic heavy ion collisions
Physical Review Letters, 2003Co-Authors: Steffen A Bass, Berndt Muller, Dinesh K. SrivastavaAbstract:: We calculate the production of high energy photons from Compton and annihilation processes as well as fragmentation off quarks in the parton cascade model. The multiple scattering of Partons is seen to lead to a substantial production of high energy photons, which rises further when parton multiplication due to final state radiation is included. The photon yield is found to be directly proportional to the number of hard collisions and thus provides valuable information on the preequilibrium reaction dynamics.
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Propagation of charm quarks in equilibrating quark-gluon plasma
Physical Review C, 1998Co-Authors: Munshi G. Mustafa, Dinesh K. SrivastavaAbstract:We study the propagation of charm quarks, produced from the initial fusion of Partons, in an equilibrating quark-gluon plasma which may be formed in the wake of relativistic collisions of gold nuclei. Initial conditions are taken from a self-screened parton cascade model and the chemical equilibration is assumed to proceed via gluon multiplication and quark production. The energy loss suffered by the charm quarks is obtained by evaluating the drag force generated by the scattering with quarks and gluons in the medium. We find that the charm quarks may lose only about 10% of their initial energy in conditions likely to be attained at the Relativistic Heavy Ion Collider, while they may lose up to 40% of their energy while propagating in the plasma created at the Large Hadron Collider. We discuss the implications for signals of the quark-gluon plasma.
C B Yang - One of the best experts on this subject based on the ideXlab platform.
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recombination of shower Partons in fragmentation processes
Physical Review C, 2004Co-Authors: C B YangAbstract:We develop the notion of shower Partons and determine their distributions in jets in the framework of the recombination model. The shower parton distributions obtained render a good fit of the fragmentation functions. We then illustrate the usefulness of the distributions in a problem where a jet is produced in the environment of thermal Partons as in heavy-ion collisions. The recombination of shower and thermal Partons is shown to be more important than fragmentation. Application to the study of two-particle correlation in a jet is also carried out.
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recombination of shower Partons at high p t in heavy ion collisions
Physical Review C, 2004Co-Authors: C B YangAbstract:A formalism for hadron production at high ${p}_{T}$ in heavy-ion collisions has been developed such that all Partons hadronize by recombination. The fragmentation of a hard parton is accounted for by the recombination of shower Partons that it creates. Such shower Partons can also recombine with the thermal Partons to form particles that dominate over all other possible modes of hadronization in the $3l{p}_{T}l8\phantom{\rule{0.3em}{0ex}}\mathrm{GeV}$ range. The results for the high ${p}_{T}$ spectra of pion, kaon, and proton agree well with experiments. Energy loss of Partons in the dense medium is taken into account on the average by an effective parameter by fitting data, and is found to be universal independent of the type of particles produced, as it should. Due to the recombination of thermal and shower Partons, the structure of jets produced in nuclear collisions is different from that in $pp$ collisions. The consequence on same-side correlations is discussed.
Klaus Geiger - One of the best experts on this subject based on the ideXlab platform.
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chemical equilibration of Partons in high energy heavy ion collisions
Physical Review D, 1993Co-Authors: Klaus Geiger, Joseph I KapustaAbstract:The chemical composition of the hot and dense parton matter formed in the central region of ultrarelativistic heavy-ion collisions is studied for the case of Au+Au collisions at energies reached at the BNL RHIC using the parton cascade model. It is shown that within this framework, which is based on current understanding of semihard and hard interactions in QCD including the emission and absorption of soft Partons, a chemical equilibration between the gluons and the quarks cannot be achieved. The gluons and [ital u], [ital d], [ital s], and [ital c] quarks all rapidly approach kinetic equilibrium with a common temperature. The gluons subsequently also achieve chemical equilibrium, but the light quarks only reach about 60% of their ideal chemical equilibrium densities. It is demonstrated that the baryon density in the central region is small relative to the total parton density, with an associated ratio of baryon chemical potential to temperature of 0.35, slowly decreasing with time. The implications of the formation of such a hot, gluon-dominated plasma for strangeness, charm, and dilepton production are discussed.
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dilepton radiation from cascading Partons in ultrarelativistic nuclear collisions
Physical Review Letters, 1993Co-Authors: Klaus Geiger, Joseph I KapustaAbstract:We compute the radiation of lepton pairs by the quarks during a central collision between gold nuclei at energy of the Brookhaven Relativistic Heavy Ion Collider ([radical][ital s] =200[ital A] GeV) within the parton cascade model. The distribution of radiated pairs evolves smoothly from the initial Drell-Yan type reactions all the way towards equilibrium radiation. Contributions from reactions involving secondary Partons dominate the Drell-Yan yield by at least a factor of 5 even at an invariant mass of 8 GeV. Therefore, experiments can test the evolution of Partons towards thermal equilibrium at these energies.
