arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 1502.00537nucl-exhep-exhep-phnucl-th
收藏

在LHC pp和Pb-Pb碰撞中逐事件平均p_T起伏

Event-by-event mean p_T fluctuations in pp and Pb-Pb collisions at the LHC

S. T. Heckel

摘要:

大型强子对撞机上的ALICE探测器被用来研究重离子碰撞中产生的夸克-胶子等离子体的性质。作为一种参考测量,质子-质子(pp)碰撞的分析也是非常重要的。在这里提出的研究中,事件的平均横向动量的波动进行了分析,在pp碰撞在sqrt(s)= 0.9,2.76和7 TeV,和Pb-Pb碰撞在sqrt(s_NN)= 2.76 TeV作为带电粒子多重性的函数。在这两个系统中,观察到超出统计预期的动态波动。在pp碰撞,没有显着的依赖于碰撞能量被发现,即使在包容性的结果相比,在低得多的碰撞能量。同样,中心A-A碰撞对碰撞能量的依赖性很小。在外围Pb-Pb数据中观察到的多重数依赖性与pp碰撞中的多重数依赖性一致。到更多的中心铅铅碰撞,从这一趋势的一个明显的偏差被发现,达到一个显着减少的波动,在大多数中心碰撞。蒙特卡罗事件发生器的比较显示良好的协议在PP,但相当大的差异,在铅铅碰撞。

英文摘要:

The ALICE detector at the LHC is used to study the properties of the Quark-Gluon Plasma produced in heavy-ion collisions. As a reference measurement, also the analysis of proton-proton (pp) collisions is very important. In the study presented here, event-by-event fluctuations of the mean transverse momentum are analysed in pp collisions at sqrt(s) = 0.9, 2.76 and 7 TeV, and Pb-Pb collisions at sqrt(s_NN) = 2.76 TeV as a function of the charged-particle multiplicity. In both systems, dynamical fluctuations beyond the statistical expectation are observed. In pp collisions, no significant dependence on collision energy is found, even in comparison to inclusive results at much lower collision energies. Likewise, central A-A collisions show only little dependence on collision energy. The multiplicity dependence observed in peripheral Pb-Pb data is in agreement with that in pp collisions. Going to more central Pb-Pb collisions, a clear deviation from this trend is found, reaching a significant reduction of the fluctuations in most central collisions. Comparisons to Monte Carlo event generators show good agreement in pp, but rather large differences in Pb-Pb collisions.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑