Bao-Chun Li

Dependence of elliptic flows on transverse momentum and number of participants in Au+Au collisions at

We discuss the dependence of elliptic flow on transverse momentum and number of participating nucleons in the framework of a multi-source model, and argue that the geometry of an initial overlap region of interaction determines the measured azimuthal asymmetry. With the help of v2(PT) fitting, the participant nucleon number at a fixed impact parameter is calculated by a geometrical picture of the participant–spectator model. In the combined framework of the two models, our results are approximately in agreement with the experimental data.

\sqrt{\mathrm{\it s_{NN}}}

The transverse momentum distributions of strange particles produced in high-energy collisions are analyzed by the thermalized cylinder model. We present a detailed comparison with the experimental data of Cu+Cu and Au+Au collisions at = 62.4 and 200 GeV. It is found that the calculated results are in agreement with the experimental data. The excitation degree of an emission source on the central axis of the cylinder increases obviously with increasing collision centrality and incident energy. There is no obvious change in the excitation degree of the emission source in the side-surface of the cylinder.

= 200 GeV

The multisource thermal model is revised for relativistic and quantum situations. It is shown that the quantum effect can be neglected due to a very small result. The distributions of particle momenta, momentum components, transverse momenta, kinetic energies, and velocities in both the classical and relativistic situations are presented to give comparisons.

Transverse momentum distributions of strange hadrons produced in nucleus?nucleus collisions at

Transverse momentum distributions of final-state particles produced in soft process in proton-proton (pp) and nucleus-nucleus (AA) collisions at Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies are studied by using a multisource thermal model. Each source in the model is treated as a relativistic and quantum ideal gas. Because the quantum effect can be neglected in investigation on the transverse momentum distribution in high energy collisions, we consider only the relativistic effect. The concerned distribution is finally described by the Boltzmann or two-component Boltzmann distribution. Our modeling results are in agreement with available experimental data.

\sqrt{\mathrm{\it s_{NN}}}=62.4

We investigate the dependence of elliptic flows v2 on transverse momentum PT for charged and strange hadrons produced in Cu?Cu collisions by using a multi-source thermal model, which includes the interaction contribution of the emission sources. The magnitude of the expansion is denoted by a expansion factor k. Our calculated results are approximately in agreement with the experimental data in Cu?Cu collisions at = 62.4 and 200 GeV, measured by the STAR Collaboration. It is found that the expansion factor increases linearly with the impact parameter from the most central (0?10%) to mid-peripheral (40?50%) collisions.

and 200 GeV

The kinetic freeze-out temperatures,

Transverse Momentum Distributions of Final-State Particles Produced in Soft Excitation Process in High Energy Collisions

T_0

Kinetic freeze-out temperatures in central and peripheral collisions: which one is larger?

T0, in nucleus–nucleus collisions at the Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) energies are extracted by four methods: (1) the Blast-Wave model with Boltzmann–Gibbs statistics (the BGBW model), (2) the Blast-Wave model with Tsallis statistics (the TBW model), (3) the Tsallis distribution with flow effect (the improved Tsallis distribution), and (4) the intercept in