J. X. Zuo

Elliptic flow of phi mesons and strange quark collectivity

Based on a multiphase transport model, we have studied the elliptic flow v{sub 2} of {phi} mesons from the reconstructed K{sup +}K{sup -} decay channel at the top Relativistic Heavy Ion Collider energy at Brookhaven National Laboratory. The dependences of v{sub 2} on transverse momentum p{sub T} and collision centrality are presented and the rescattering effect of {phi} mesons in the hadronic phase is also investigated. The results show that experimental measurement of v{sub 2} for {phi} mesons can retain the early collision information before the {phi} decays and that the {phi} v{sub 2} value obeys the constituent quark number scaling that has been observed for other mesons and baryons. Our study indicates that the {phi} v{sub 2} mostly reflects partonic-level collectivity developed during the early stage of the nucleus-nucleus collision and the strange and light up/down quarks have developed similar angular anistropy properties at the hadronization.

Surveying the nucleon-nucleon momentum correlation function in the framework of quantum molecular dynamics model

Momentum correlation functions of nucleon-nucleon pairs are presented for reactions with C isotopes bombardinga 12 Ctargetwithintheframeworkoftheisospin-dependentquantummolecular dynamics model.The binding-energy dependence of the momentum correlation functions is also explored, and other factors that have an influence on momentum correlation functions are investigated. These factors include momentum-dependent nuclear equations of state, in-medium nucleon-nucleon cross sections, impact parameters, total pair momenta, and beam energy. In particular, the rise and the fall of the strength of momentum correlation functions at lower relative momentum are shown with an increase in beam energy.

Isoscaling behavior in fission dynamics

The fission processes of 112 Sn + 112 Sn and 116 Sn + 116 Sn are simulated with the combination of the Langevin equation and the statistical decay model. The masses of two fission fragments are given by assuming the process of symmetric fission or asymmetric fission by the Monte Carlo sampling with the Gaussian probability distribution. From the analysis to the isotopic/isotonic ratios of the fission fragments from both reactions, the isoscaling behavior has been observed and investigated

Baryon-strangeness correlations in parton/hadron transport model for Au+Au collisions at root s(NN)=200 GeV

Baryon-strangeness correlation (CBS) has been investigated with a multi-phase transport model (AMPT) in 197Au+197Au collisions at 200 GeV. The centrality dependence of CBS is presented within the model, from partonic phase to hadronic matter. We find that the system still reserves partial predicted signatures of CBS after parton coalescence. But after hadronic rescattering, the predicted signatures will be obliterated completely. So it seems that both coalescence hadronization process and hadronic rescattering are responsible for the disappearance of the CBS signatures.

ANISOTROPIC FLOWS OF Ω BARYON DUE TO PARTON CASCADES

The directed flow v1, elliptic flow v2 and the fourth order anisotropic flow v4 of Ω, p, K and π have been studied in the framework a parton cascade model, namely A Multi-Phase Transport (AMPT) model for 197Au + 197Au collisions at

Δ-scaling and heat capacity in relativistic ion collisions

\sqrt{^SNN} = 200\ {\rm GeV}

Measurements of reaction cross section and fragment momentum distribution for N=10 proton-rich isotones

. Transverse momentum (pT) dependence of v2 and v4 and rapidity dependence of v1 are presented. The results show that the v2 of Ω obeys the constituent quark number scaling which has been observed for other mesons and baryons. It is seen that

Three-particle correlations from parton cascades in Au + Au collisions

v_4/v_2^2

Energy dependence of directed flow in Au+Au collisions from a multiphase transport model

is scaled better by 1.2 than 0.5. The comparisons of Ω elliptic flow v2 among the default version of AMPT, the melting version of AMPT and RQMD model calculation shows that parton scattering process is important to reproduce the sizeable v2, and the string melting AMPT model preferably reproduces Ω elliptic flow v2.

Time evolution of Mach-like structure in a partonic transport model

The Δ-scaling method has been applied to the total multiplicity distribution of the relativistic ion collisions of p+p, C+C and Pb+Pb which were simulated by a Monte Carlo package, LUCIAE 3.0. It is found that the Δ-scaling parameter decreases with increasing system size. Moreover, the heat capacities of different mesons and baryons have been extracted from the event-by-event temperature fluctuation in the region of low transverse mass and they shows the dropping trend with increasing impact parameter.