论文部分内容阅读
The kinetic freeze-out temperatures, T0, in nucleus-nucleus collisions at the Relativistic Heavy Ion Collider (RHIC) and Large Hadron Collider (LHC) ener-gies 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 T =T0+am0(the alteative method),where m0denotes the rest mass and T denotes the effective tem-perature which can be obtained by different distribution functions.It is found that the relative sizes of T0in central and peripheral collisions obtained by the conventional BGBW model which uses a zero or nearly zero transverse flow velocity,βT,are contradictory in tendency with other methods.With a re-examination for βTin the first method, in which βTis taken to be ~(0.40 ± 0.07)c, a recalcula-tion presents a consistent result with others. Finally, our results show that the kinetic freeze-out temperature in central collisions is larger than that in peripheral collisions.