"Table 169" of "Anisotropic flow and flow fluctuations of identified hadrons in Pb$-$Pb collisions at $\sqrt{s_{\mathrm{NN}}}$ = 5.02 TeV"

The first measurements of elliptic flow of $\mathrm{\pi}^{\pm}$, $\mathrm{K}^{\pm}$, $\mathrm{p}+\bar{\mathrm{p}}$, $\mathrm{K_{S}^{0}}$, $\Lambda+\bar{\Lambda}$, $\mathrm{\phi}$, $\mathrm{\Xi^{\mp}}$, and $\mathrm{\Omega^{\mp}}$ using multiparticle cumulants in Pb--Pb collisions at $\sqrt{s_{\rm NN}} = 5.02$ TeV are presented. Results obtained with two- ($v_2\{2\}$) and four-particle cumulants ($v_2\{4\}$) are shown as a function of transverse momentum, $p_{\rm T}$, for various collision centrality intervals. Combining the data for both $v_2\{2\}$ and $v_2\{4\}$ also allows us to report the first measurements of the mean elliptic flow, elliptic flow fluctuations, and relative elliptic flow fluctuations for various hadron species. These observables probe the event-by-event eccentricity fluctuations in the initial state and the contributions from the dynamic evolution of the expanding quark--gluon plasma. The characteristic features observed in previous $p_{\rm T}$-differential anisotropic flow measurements for identified hadrons with two-particle correlations, namely the mass ordering at low $p_{\rm T}$ and the approximate scaling with the number of constituent quarks at intermediate $p_{\rm T}$, are similarly present in the four-particle correlations and the combinations of $v_2\{2\}$ and $v_2\{4\}$. In addition, a particle species dependence of flow fluctuations is observed that could indicate a significant contribution from final state hadronic interactions. The comparison between experimental measurements and CoLBT model calculations, which combine the various physics processes of hydrodynamics, quark coalescence, and jet fragmentation, illustrates their importance over a wide $p_{\rm T}$ range.本研究报道了在质心系能量√s_NN=5.02 TeV的铅-铅（Pb--Pb）碰撞中，利用多粒子累积量（multiparticle cumulants）对π±、K±、p+$ar{p}$、K_S^0、Λ+$ar{Λ}$、φ、Ψ∓和Ω∓的椭圆流（elliptic flow）进行的首次测量。研究给出了两粒子累积量（记为v₂{2}）与四粒子累积量（记为v₂{4}）的结果，将其作为横向动量（transverse momentum, p_T）的函数，并覆盖不同碰撞中心度（collision centrality）区间。结合v₂{2}与v₂{4}的实验数据，我们还能够首次报道不同强子种类（hadron species）的平均椭圆流、椭圆流涨落以及相对椭圆流涨落的测量结果。这些可观测量可用于探究初始态的逐事件偏心率涨落（event-by-event eccentricity fluctuations），以及膨胀夸克胶子等离子体（quark-gluon plasma）的动态演化贡献。此前利用双粒子关联（two-particle correlations）对已鉴别强子进行的p_T微分各向异性流测量中观测到的特征，具体表现为低p_T区间的质量排序，以及中间p_T区间随组分夸克数（number of constituent quarks）的近似标度行为，该特征在四粒子关联以及v₂{2}与v₂{4}的组合结果中同样存在。此外，本研究观测到流涨落存在强子种类依赖性，该现象或表明末态强子相互作用存在显著贡献。将实验测量结果与结合流体力学（hydrodynamics）、夸克聚结（quark coalescence）与喷注碎裂（jet fragmentation）等多种物理过程的CoLBT模型计算结果进行对比，凸显了该模型在宽横向动量范围内的重要意义。