论文标题
$ \ sqrt {s _ {_ {_ {\ text {nn}}}} = 2.76 $ tev pbpb碰撞与epos碰撞
Event-by-event investigation of the two-particle source function in $\sqrt{s_{_{\text{NN}}}}=2.76$ TeV PbPb collisions with EPOS
论文作者
论文摘要
EPOS模型模拟的铅铅碰撞中的两粒子源函数的研究以$ \ sqrt {s _ {_ {\ text {nn}}}} = 2.76 $ tev的提示。使用EPOS的最后阶段，将两粒子源函数直接按事件，kaons和质子分别重建。在各个事件中，所有三个粒子物种都观察到了莱维源形状，从高斯形状明显偏离。源参数被提取为碰撞中心的函数和一对平均横向质量（$ m _ {\ text {t}} $）。发现Lévy指数被相应地订购为颗粒质量。根据高斯流体动力学预测，发现Lévy量表参数可针对所有具有$ m _ {\ text {t}} $的粒子物种扩展；但是，没有$ m _ {\ text {t}} $ - 在这些物种中发现的缩放。如果酸痛，还研究了衰减产物和辐射脱落的作用。当分析中还包括衰减产物时，Lévy指数会减少。如果没有强烈的拆卸和衰减产品，源形状就接近高斯。
The investigation of the two-particle source function in lead-lead collisions simulated by the EPOS model at a center of mass energy per nucleon pair of $\sqrt{s_{_{\text{NN}}}}=2.76$ TeV is presented. The two-particle source functions are reconstructed directly on an event-by-event basis for pions, kaons and protons separately, using the final stage of EPOS. A Lévy source shape is observed for all three particle species in the individual events, deviating significantly from a Gaussian shape. The source parameters are extracted as functions of collision centrality and pair average transverse mass ($m_{\text{T}}$). The Lévy exponent is found to be ordered accordingly to particle mass. The Lévy scale parameter is found to scale for all particle species with $m_{\text{T}}$ according to Gaussian hydrodynamical predictions; however, there is no $m_{\text{T}}$-scaling found across these species. In case of pions, the effects of the decay products and hadronic rescattering are also investigated. The Lévy exponent is decreased when decay products are also included in the analysis. Without hadronic rescattering and decay products, the source shape is close to a Gaussian.
