论文标题
PP和P-PB碰撞的两粒子横向动量相关性在CERN大型强子对撞机上可用
Two-particle transverse momentum correlations in pp and p-Pb collisions at energies available at the CERN Large Hadron Collider
论文作者
论文摘要
最近在CERN大型强子碰撞器（LHC）上可在PB-PB碰撞中测量的两个粒子横向动量差异相关器提供了一种额外的工具，可以帮助您深入了解粒子生产机制和推断传输性能，例如剪切粘度的比率与剪切粘度与入学密度的比率，在PB-PB Collions中产生的培养基。在小型碰撞系统中，在低横向动量下测得的纵向纵向相关性和大的方位角各向异性，即LHC能量在LHC Energies上的PP和P-PB类似于集体行为的表现。这表明在这些小型碰撞系统中可能会产生局部平衡的物质，类似于PB-PB碰撞中观察到的物质。在这项工作中，在$ \ sqrt {s} = 7 $ tev和$ \ sqrt {s _ {\ rm nn}} = 5.02 $ tev中，以$ \ sqrt {s} = 7 $ tev和$ \ sqrt {s _ {s _ {s _ {s _ {s _ {s _ {s _ {s} = 5.02 $ tev，以寻求证据，以寻求证据以寻求可见效果。具体而言，研究相关因子的强度和形状是生成粒子多样性的函数，以识别纵向拓宽的证据，这些证据可能揭示了这些较小的系统中粘性效应的存在。与蒙特卡洛事件发生器的预测相比，将测得的相关器及其从PP和P-PB到PB-PB碰撞的演变，并讨论了粘性效应的潜在存在。
Two-particle transverse momentum differential correlators, recently measured in Pb--Pb collisions at energies available at the CERN Large Hadron Collider (LHC), provide an additional tool to gain insights into particle production mechanisms and infer transport properties, such as the ratio of shear viscosity to entropy density, of the medium created in Pb-Pb collisions. The longitudinal long-range correlations and the large azimuthal anisotropy measured at low transverse momenta in small collision systems, namely pp and p-Pb, at LHC energies resemble manifestations of collective behaviour. This suggests that locally equilibrated matter may be produced in these small collision systems, similar to what is observed in Pb-Pb collisions. In this work, the same two-particle transverse momentum differential correlators are exploited in pp and p-Pb collisions at $\sqrt{s} = 7$ TeV and $\sqrt{s_{\rm NN}} = 5.02$ TeV, respectively, to seek evidence for viscous effects. Specifically, the strength and shape of the correlators are studied as a function of the produced particle multiplicity to identify evidence for longitudinal broadening that might reveal the presence of viscous effects in these smaller systems. The measured correlators and their evolution from pp and p--Pb to Pb--Pb collisions are additionally compared to predictions from Monte Carlo event generators, and the potential presence of viscous effects is discussed.
