Abstract There is a well-established relation between the spatial asymmetry in the initial stage of a heavy-ion collision and the final momentum anisotropy, which allows for a separation of effects from initial conditions vs. later evolution and has proved exceptionally powerful. However, until recently it has only been studied in two dimensions — either through boost-invariant simulations or studying only quantities at mid-rapidity. We explore an extension to 3 dimensions, in order to determine whether a similar understanding can be obtained for the rapidity dependence of the collision system. In particular, we introduce rapidity-dependent eccentricities and investigate a trivial extension of the 2D eccentricity scaling of elliptic and triangular flow, as well as a way to systematically improve these initial-state estimators. We then explore the dependence of the resulting new response coefficients on shear viscosity and initial total energy.

中文翻译：

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相对论重离子碰撞中依赖于速度的偏心率缩放

摘要 重离子碰撞初始阶段的空间不对称性与最终动量各向异性之间存在公认的关系，这使得初始条件与后期演化的影响分离，并已被证明非常强大。然而，直到最近，它才在二维方面进行了研究——要么通过增强不变模拟，要么只研究中等速度的数量。我们探索了 3 维的扩展，以确定是否可以获得对碰撞系统的快速依赖性的类似理解。特别是，我们引入了与速度相关的离心率，并研究了椭圆和三角流的二维离心率标度的微不足道的扩展，以及一种系统地改进这些初始状态估计器的方法。