标题： 横向动量依赖的Hanbury-Brown/Twiss关联半径 显示英文标题

标题： Transverse Momentum Dependence of Hanbury-Brown/Twiss Correlation Radii

摘要： 哈勃-布朗/特维斯（HBT）干涉测量半径的横向动量依赖性对于二体关联函数提供了实验上研究重离子碰撞中集体动力学的途径。 我们提出了一种解析近似方案，用于这些HBT半径，该方案结合了最近推导出的模型无关表达式与发射函数鞍点的近似确定。 该方法适用于一个纵向增强不变的流体力学模型，其中重离子碰撞在尖锐超曲面上冻结。 解析近似迅速收敛到数值计算的相关函数的宽度，并正确再现其精确的横向动量依赖性。 然而，在我们的近似方案中，高阶修正至关重要，之前发表的具有简单$m_{\perp}$伸缩行为的最低阶结果在定量和定性上都是不可靠的。 显示英文摘要

摘要： The transverse momentum dependence of Hanbury-Brown/Twiss (HBT) interferometry radii for 2-body correlation functions provides experimental access to the collective dynamics in heavy-ion collisions. We present an analytical approximation scheme for these HBT radii which combines the recently derived model-independent expressions with an approximate determination of the saddle point of the emission function. The method is illustrated for a longitudinally boost-invariant hydrodynamical model of a heavy ion collision with freeze-out on a sharp hypersurface. The analytical approximation converges rapidly to the width of the numerically computed correlation function and reproduces correctly its exact transverse momentum dependence. However, higher order corrections within our approximation scheme are essential, and the previously published lowest order results with simple $m_{\perp}$ scaling behaviour are quantitatively and qualitatively unreliable.