论文标题
一种改进的方法，可以在相对论重型离子碰撞中访问初始状态
An improved method to access initial states in relativistic heavy-ion collisions
论文作者
论文摘要
重型离子碰撞中的可观察物通常分为中心，这反映出在影响参数范围内的事件中的平均值，包括各种初始状态配置。先前已证明使用每个中心内中子的多个binning方法，可提供对具有罕见初始状态条件的事件的访问。这项工作表明，在量化标准中心性和观众中子套件之间的差异方面有所改善，以访问初始状态特性。观察到在固定参与核子数量下具有较高初始状态密度的事件的选择，从而导致最终颗粒的产生和较小的椭圆流。中心性和观众组合中可观察到的相对差异显示出对在初始状态（例如三角形流量）中受影响参数波动主导的观察到的敏感性降低。该属性使观众binning方法成为将几何贡献与初始状态的随机波动分开为最终状态可观察物的好候选者。
Observables in heavy-ion collisions are generally categorized into centralities, which reflect an average over events within a range of impact parameter including a wide variety of initial state configurations. A multiple binning method using spectator neutrons within each centrality has been previously shown to provide access to events with rare initial state conditions. This work suggests an improvement in quantifying the difference between standard centrality and spectator neutron binning towards accessing the initial state properties. A selection of events with higher initial state density at fixed participating nucleon number was observed to result in larger final state particle production and smaller elliptic flow. The relative difference between observables in centrality and spectator binning shows reduced sensitivity for the observables dominated by impact parameter fluctuations in initial state such as triangular flow. This property makes the spectator binning method a good candidate to separate geometric contributions from random fluctuations in initial state towards final state observables.
