American Physical Society, 1 Research Road, Ridge, New York 11961, USA.
Physics Department, Brookhaven National Laboratory, Building 510A, Upton, New York 11973, USA.
Phys Rev Lett. 2018 Jan 26;120(4):042002. doi: 10.1103/PhysRevLett.120.042002.
Qualitative features of multiparticle correlations in light-heavy ion (p+A) collisions at RHIC and LHC are reproduced in a simple initial state model of partons in the projectile coherently scattering off localized domains of color charge in the heavy nuclear target. These include (i) the ordering of the magnitudes of the azimuthal angle nth Fourier harmonics of two-particle correlations v_{n}{2}, (ii) the energy and transverse momentum dependence of the four-particle Fourier harmonic v_{2}{4}, and (iii) the energy dependence of four-particle symmetric cumulants measuring correlations between different Fourier harmonics. Similar patterns are seen in an Abelian version of the model, where we observe v_{2}{2}>v_{2}{4}≈v_{2}{6}≈v_{2}{8} of two, four, six, and eight particle correlations. While such patterns are often interpreted as signatures of collectivity arising from hydrodynamic flow, our results provide an alternative description of the multiparticle correlations seen in p+A collisions.
在轻重离子（p+A）碰撞中，RHIC 和 LHC 的多粒子关联的定性特征在一个简单的初始态模型中得到了重现，其中射弹中的部分子coherent 地散射到重核靶标中局部色荷的域中。这些特征包括：（i）两粒子关联的第 n 个角向傅里叶谐波 v_{n}{2}的大小排序；（ii）四粒子傅里叶谐波 v_{2}{4}的能量和横向动量依赖性；（iii）测量不同傅里叶谐波之间相关性的四粒子对称累积量的能量依赖性。在模型的阿贝尔版本中也观察到了类似的模式，其中我们观察到两、四、六和八粒子关联的 v_{2}{2}>v_{2}{4}≈v_{2}{6}≈v_{2}{8}。虽然这些模式通常被解释为源于流体力学流动的集体性的特征，但我们的结果为 p+A 碰撞中观察到的多粒子关联提供了另一种描述。
