论文标题
与爱丽丝相关的粒子产生的系统大小依赖性
System-size dependence of particle production at mid- and forward rapidity with ALICE
论文作者
论文摘要
在高能核碰撞中产生的带电颗粒和包含光子的假性密度是表征碰撞的全局特性（例如所达到的能量密度）的必不可少的可观察力，并为蒙特卡洛模型计算提供了重要的约束。在LHC运行1和运行2个配置中，Alice具有较大的覆盖范围，可以在伪型范围（$ -3.4〜η〜 <〜5.0 $）上测量带电的颗粒，将来自硅像素检测器（SPD）和正向多样性检测器（FMD）的数据组合在一起。使用光子多数探测器（PMD）在正向快速性测量包含光子，覆盖伪型范围$ 2.3〜 <〜η〜 <〜3.9 $。在$ \ sqrt {s _ {\ rm nn}} $ = 5.02 tev使用运行1和运行2个数据的$ \ sqrt {s _ {\ rm nn}} $ = 5.02 $ = 5.02 TEV中，以PP，P $ -PB和PB $ -PB碰撞测量的带电颗粒假性密度进行了新结果。报告了$ \ sqrt {s _ {\ rm nn}} $ = 5.02 tev的p $ -pb碰撞的包含光子生产。带电的粒子快速密度源自测量的带电粒子假性密度，然后通过正态分布进行参数化。这使我们能够研究快速分布的宽度的演变，这是所有三个碰撞系统中参与者数量的函数。还讨论了针对Alice Run 3配置设计的新内部跟踪系统（ITS）的性能，以用于$ \ sqrt {s} $ = 0.9 TEV的PILOT BEAM PP碰撞。
The pseudorapidity densities of charged particles and inclusive photons produced in high energy nuclear collisions are essential observables to characterise the global properties of the collisions, such as the achieved energy density, and to provide important constraints for Monte Carlo model calculations. In the LHC Run 1 and Run 2 configurations, ALICE had large coverage to measure charged particles over a pseudorapidity range ($-3.4~<~η~<~5.0$), combining the data from the Silicon Pixel Detector (SPD) and the Forward Multiplicity Detector (FMD). The inclusive photons are measured at forward rapidity using the Photon Multiplicity Detector (PMD), covering the pseudorapidity range $2.3~<~η~<~3.9$. New results on charged-particle pseudorapidity densities measured in pp, p$-$Pb, and Pb$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV using Run 1 and Run 2 data are presented. Inclusive photon production is reported for p$-$Pb collisions at $\sqrt{s_{\rm NN}}$ = 5.02 TeV. The charged-particle rapidity densities are derived from the measured charged-particle pseudorapidity densities, and then parameterized by a normal distribution. This allows us to study the evolution of the width of the rapidity distributions as a function of the number of participants in all three collision systems. The performance of the new Inner Tracking System (ITS) designed for ALICE Run 3 configuration is also discussed for pilot beam pp collisions at $\sqrt{s}$ = 0.9 TeV.
