相对论重离子碰撞中逐事件横动量起伏对多重数依赖性的蒙特-卡洛研究

利用RQMD与EPOS蒙特-卡洛事件产生器对STAR实验组130GeV金-金碰撞中逐事件横动量起伏的多重数依赖性进行了研究。发现两种蒙特-卡洛产生器都能得到单事件平均横动量随多重数变化。EPOS能够复现STAR所发现的差异因子!"ptn随多重数的升高而首先上升然后下降,但其变化比STAR实验观察到的更陡,且峰的位置比实验结果偏向较低的多重数。RQMD所得到的差异因子#$ptn随多重数的上升较缓,没有明显的峰。

A Monte-Carlo Study on the Multiplicity Dependence of Event-by-event Transverse Momentum Fluctuation in Relativistic Heavy Ion Collision

The experimental observation on the multiplicity dependence of event-by-event transverse momentum fluctuation in 130Gev Au-Au collisions is studied by using Monte Carlo simulations. It is found that the RQMD and EPOS Monte Carlo generators are both able to describe the multiplicity dependence of event-by-event transverse momentum fluctuation. There are some differences between the results of these two simulations. In RQMD Monte Carlo simulation, the variation trend of "difference factor" with respect to the multiplicity first rises and then falls down, mimic the STAR's observation, where the variation is sharper and the corresponding peak appears at lower multiplicity than those in the experimental result. The "difference factor" increases with the multiplicity much slower in EPOS simulation and no obvious peak can be seen.