共查询到20条相似文献,搜索用时 15 毫秒
1.
A. Kozlov 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):836-841
The production of the low-mass dielectrons is considered to be a powerful tool to study the properties of the hot and dense
matter created in the ultra-relativistic heavy-ion collisions. We present the preliminary results on the first measurements
of the low-mass dielectron continuum in Au + Au collisions and the φ-meson production measured in Au + Au and d + Au collisions at
= 200GeV performed by the PHENIX experiment. 相似文献
2.
Jean-Yves Ollitrault 《Pramana》2006,67(5):899-914
I review recent results from the heavy-ion programme at the Brookhaven Relativistic Heavy Ion Collider and their interpretation. 相似文献
3.
Anisotropic transverse flow is studied in Pb+Pb and Au+Au collisions at SPS and RHIC energies. The centrality and transverse momentum dependence at midrapidity of the elliptic flow coefficient v2 is calculated in the hydrodynamic and low density limits. Hydrodynamics is found to agree well with the RHIC data for semicentral collisions up to transverse momenta of 1–1.5 GeV/c, but it considerably overestimates the measured elliptic flow at SPS energies. The low density limit LDL is inconsistent with the measured magnitude of v2 at RHIC energies and with the shape of its pt-dependence at both RHIC and SPS energies. The success of the hydrodynamic model points to very rapid thermalization in Au+Au collisions at RHIC and provides a serious challenge for kinetic approaches based on classical scattering of on-shell particles. 相似文献
4.
5.
In this contribution I present a review on the actual status of dilepton measurements at SPS and RHIC energies and the current theoretical interpretations. Model independent results will be pointed out for both energies. Due to partially conflicting theoretical concepts I will highlight the open questions that may be solved by extended theoretical as well as experimental studies. 相似文献
6.
Itzhak Tserruya 《Pramana》2003,60(4):577-592
The field of relativistic heavy-ion physics is reviewed with emphasis on new results and highlights from the first run of
the relativistic heavy-ion collider at BNL and the 15 year research programme at the super proton synchrotron (SPS) at CERN
and the AGS at BNL. 相似文献
7.
Bedangadas Mohanty 《Pramana》2006,67(5):927-935
We present some of the important experimental results from nucleus-nucleus collision studies carried out by the STAR experiment
at Relativistic Heavy Ion Collider (RHIC). The results suggests that central Au+Au collisions at RHIC has produced a dense
and rapidly thermalizing matter with initial energy densities above the critical values predicted by lattice QCD for establishment
of a quark-gluon plasma (QGP). 相似文献
8.
J. T. Mitchell 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):851-853
The PHENIX experiment at the Relativistic Heavy Ion Collider (RHIC) has made measurements of event-by-event fluctuations in
the charged-particle multiplicity as a function of collision energy, centrality, collision species, and transverse momentum
in several heavy-ion collision systems. It is observed that the fluctuations in terms of σ
2/μ
2 exhibit a universal power law scaling as a function of Nparticipants that is independent of the transverse momentum range of the measurement. 相似文献
9.
Arghya Chatterjee Toshihiro Nonaka ShinIchi Esumi Xiaofeng Luo 《中国物理C(英文版)》2021,45(10):104001-104001-11
Mix-cumulants of conserved charge distributions are sensitive observables for probing properties of the QCD medium and phase transition in heavy-ion collisions. To perform precise measurements, efficiency correction is one of the most important step. In this study, using the binomial efficiency model, we derive efficiency correction formulas for mutually exclusive and inclusive variables. The UrQMD model is applied to verify the validity of these formulas for different types of correlations. Furthermore, we investigate the effect of the multiplicity loss and contamination emerging from the particle identifications. This study provides important steps toward future measurements of mixed-cumulants in relativistic heavy-ion collisions. 相似文献
10.
We analyze the spectra of pions and protons in heavy-ion collisions at relativistic energies from 2 A GeV to 65+65 A GeV by
using a jet-implemented hadron-string cascade model. In this energy region, hadron transverse mass spectra first show softening
until SPS energies, and re-hardening may emerge at RHIC energies. Since hadronic matter is expected to show only softening
at higher energy densities, this re-hardening of spectra can be interpreted as a good signature of the quark-gluon plasma
formation 相似文献
11.
We present Monte-Carlo simulations for heavy-ion collisions combining PYTHIA and the McGill-AMY formalism to describe the evolution of hard partons in a soft background, modelled using hydrodynamic simulations. MARTINI generates full event configurations in the high pT region that take into account thermal QCD and QED effects as well as effects of the evolving medium. This way it is possible to perform detailed quantitative comparisons with experimental observables. 相似文献
12.
We present here a brief summary of the presentation given at the Quark-Gluon-Plasma Thermalization Workshop in Vienna, Austria in August 2005, directly following the International Quark Matter Conference in Hungary. 相似文献
13.
R. Andrade F. Grassi Y. Hama T. Kodama O. Socolowski jr. B. Tavares 《The European Physical Journal A - Hadrons and Nuclei》2006,29(1):23-26
Elliptic flow at RHIC is computed event by event with NeXSPheRIO. Reasonable agreement with experimental results on v
2(η) is obtained. Various effects are studied as well: reconstruction of impact parameter direction, freeze-out temperature,
equation of state (with or without crossover), emission mechanism. 相似文献
14.
K. Wosińska J. Pluta F. Hanappe L. Stuttge J. C. Angelique B. Benoit E. de Goes Brennand G. Bizard J. Colin G. Costa P. Desesquelles O. Dorvaux D. Durand B. Erazmus S. Kuleshov R. Lednicky M. Marques Th. Materna K. Mikhailov G. Papatheofanous T. Pawlak A. Staranowicz A. Stavinskiy B. Tamain A. Vlasov L. Vorobyev 《The European Physical Journal A - Hadrons and Nuclei》2007,32(1):55-59
The measurement of the two-particle correlation function for different particle species allows to obtain information about
the development of the particle emission process: the space-time properties of emitting sources and the emission time sequence
of different particles. The single-particle characteristics and two-particle correlation functions for neutral and charged
particles registered in forward direction are used to determine that the heavy fragments (deuterons and tritons) are emitted
in the first stage of the reaction (pre-equilibrium source) while the majority of neutrons and protons originates from the
long-lived quasi-projectile. The emission time sequence of protons, neutrons and deuterons has been obtained from the analysis
of non-identical particle correlation functions. 相似文献
15.
16.
M. J. Leitch 《The European Physical Journal A - Hadrons and Nuclei》2007,31(4):868-874
At the Relativistic Heavy-Ion Collider (RHIC) collisions of heavy ions at nucleon-nucleon energies of 200GeV appear to have
created a new form of matter thought to be a deconfined state of the partons that ordinarily are bound in nucleons. We discuss
the evidence that a thermalized partonic medium, usually called a Quark Gluon Plasma (QGP), has been produced. Then, we discuss
the effect of this high-density medium on the production of jets and their pair correlations. Next, we look at direct photons
as a clean electro-magnetic probe to constrain the initial hard scatterings. Finally, we review the developing picture for
the effect of this medium on the production of open heavy quarks and on the screening by the QGP of heavy-quark bound states. 相似文献
17.
Bedangadas Mohanty 《Pramana》2003,60(4):613-625
Results from the photon multiplicity measurements using a fine granularity pre-shower photon multiplicity detector (PMD) at
CERN SPS are discussed. These include study of pseudorapidity distributions of photons, scaling of photon multiplicity with
number of participating nucléons, centrality dependence of 〈p
T〉 of photons, event-by-event fluctuations in photon multiplicity and localised charged-neutral fluctuations. Basic features
of the PMD to be used in STAR experiment at RHIC and in ALICE experiment at LHC are also discussed. 相似文献
18.
Jet quenching has successfully served as a hard probe to study the properties of Quark-Gluon Plasma (QGP). As a multi-particle system, jets require time to develop from a highly virtual parton to a group of partons close to mass shells. In this study, we present a systematical analysis on the effects of this formation time on jet quenching in relativistic nuclear collisions. Jets from initial hard scatterings were simulated with Pythia, and their interactions with QGP were described using a Linear Boltzmann Transport (LBT) model that incorporates both elastic and inelastic scatterings between jet partons and the thermal medium. Three different estimations of the jet formation time were implemented and compared, including instantaneous formation, formation from single splitting, and formation from sequential splittings, before which no jet-medium interaction was assumed. We found that deferring the jet-medium interaction with a longer formation time not only affects the overall magnitude of the nuclear modification factor of jets but also its dependence on the jet transverse momentum. 相似文献
19.
Investigation of experimental observables in search of the chiral magnetic effect in heavy-ion collisions in the STAR experiment 下载免费PDF全文
Subikash Choudhury Xin Dong Jim Drachenberg James Dunlop ShinIchi Esumi 冯毅程 Evan Finch 胡昱 Jiangyong Jia Jerome Lauret Wei Li 廖劲峰 林裕富 Mike Lisa Takafumi Niida Robert Lanny Ray Masha Sergeeva 申迪宇 施舒哲 Paul Sorensen 唐爱洪 Prithwish Tribedy Gene Van Buren Sergei Voloshin 王福强 王钢 徐浩洁 徐之湾 Nanxi Yao 赵杰 《中国物理C(英文版)》2022,46(1):014101-014101-17
The chiral magnetic effect(CME)is a novel transport phenomenon,arising from the interplay between quantum anomalies and strong magnetic fields in chiral systems.In high-energy nuclear collisions,the CME may survive the expansion of the quark-gluon plasma fireball and be detected in experiments.Over the past two decades,experimental searches for the CME have attracted extensive interest at the Relativistic Heavy Ion Collider(RHIC)and the Large Hadron Collider(LHC).The main goal of this study is to investigate three pertinent experimental approaches:the$\gamma$correlator,the R correlator,and the signed balance functions.We exploit simple Monte Carlo simulations and a realistic event generator(EBE-AVFD)to verify the equivalence of the core components among these methods and to ascertain their sensitivities to the CME signal and the background contributions for the isobar collisions at the RHIC. 相似文献
20.
We investigate how thermalization of gluons depends on the initial conditions assumed in ultrarelativistic heavy-ion collisions
at RHIC. The study is based on simulations employing the pQCD inspired parton cascade solving the Boltzmann equation for gluons.
We consider independently produced minijets with p
T > p
0 = 1.3-2.0GeV and a color glass condensate as possible initial conditions for the freed gluons. It turns out that full kinetic
equilibrium is achieved slightly sooner in denser systems and its timescale tends to saturate. Compared with the kinetic equilibration
we find a stronger dependence of chemical equilibration on the initial conditions. 相似文献