标题： 探索椭圆流和三角流的中心依赖性 显示英文标题

标题： Exploring the centrality dependence of elliptic and triangular flows

摘要： 本文详细研究了相对论重离子碰撞初始状态中的椭圆度和三角形偏心率。基于彩色玻璃凝聚有效理论的横向平面随机分布能量密度源模型被采用。 如果将各向异性流的第二阶$v_2$和第三阶$v_3$谐波简单地假设为与偏心率$\varepsilon_2$和$\varepsilon_3$成正比（这是一个合理的近似），那么该模型可以很好地描述ALICE和ATLAS在质心能量为每核子对5.02 TeV的Pb+Pb碰撞数据，在广泛的中心性范围内。 偏心率$\varepsilon_2$与碰撞几何密切相关，并且其中心性依赖性主要由入射核饱和脉冲均匀分布区域的边缘扩散决定。 偏心率$\varepsilon_3$完全由重叠核区域内源位置的混沌涨落决定，并且主要取决于重叠面积。 显示英文摘要

摘要： A detailed study of elliptical and triangular eccentricities in the initial state of relativistic heavy ion collisions is presented. A model of randomly distributed sources of energy density in the transverse plane based on the effective theory of Color Glass Condensate is used. This model describes well the ALICE and ATLAS data for Pb+Pb collisions at center-of-mass energy 5.02 TeV per nucleon pair in a wide range of centralities, if the second $v_2$ and third $v_3$ harmonics of the anisotropic flow are simply implied to be proportional to the eccentricities $\varepsilon_2$ and $\varepsilon_3$ as a reasonable approximation. The eccentricity $\varepsilon_2$ is closely related with the collision geometry and its centrality dependence is mainly determined by the edge diffuseness of the region of the uniform distribution of the saturation pulse of the oncoming nucleus. The eccentricity $\varepsilon_3$ is completely determined by the chaotic fluctuations of the source position in the region of overlapping nuclei and is substantially dependent on the overlap area only.