AI 中文总结
本研究将动力学速率方程纳入（3+1）维粘性流体动力学模拟，分析RHIC和LHC重离子碰撞中底夸克偶素输运，解释了Υ(1S)在两装置处产生量级相当的实验现象。
AI 中文摘要
本研究通过将动力学速率方程纳入膨胀夸克胶子等离子体（QGP）的（3+1）维粘性流体动力学模拟，对RHIC和LHC重离子碰撞中的底夸克偶素输运展开研究。主要输运参数为各底夸克偶素态Y的非弹性反应率与平衡极限；前者取自热力学T矩阵形式论，结合格点QCD的最新约束，且包含干涉效应与介质内结合能，由此得到强耦合QGP特有的高反应率。平衡极限由相关介质内底夸克偶素与底夸克质量计算得出。可观测量计算涵盖共9种Y态（直至3S与2P态），其衰变矩阵由真空分支比估算。在LHC中，高反应率会快速压低激发态初始布居，使再生成为甚至较周边碰撞中激发态的主要来源；而结合更强束缚的基态Υ(1S)，在中心碰撞中仍有显著的原始成分留存。另一方面，RHIC能量下再生整体效应较小。结合核吸收效应，这解释了实验观测到的现象：尽管LHC处QGP达到的温度显著更高，但RHIC与LHC处Υ(1S)的产生量级相当。
英文摘要
Bottomonium transport is studied in heavy-ion collisions at RHIC and the LHC by implementing a kinetic rate equation into (3+1)D viscous hydrodynamic simulations of an expanding quark-gluon plasma (QGP). The two main transport parameters are the inelastic reaction rates and equilibrium limits for each individual bottomonium state, $Y$. The former are taken from the thermodynamic $T$-matrix formalism with recent constraints from lattice-QCD and including interference effects and in-medium binding energies, resulting in large rates characteristic of a strongly coupled QGP. The equilibrium limits are evaluated from pertinent in-medium bottomonium and bottom-quark masses. The calculation of observables includes a total of nine $Y$ states (up to 3$S$ and 2$P$) with a feed-down matrix estimated from vacuum branching fractions. At the LHC, the large reaction rates rapidly suppress the initial population of excited states, rendering regeneration their main source even in rather peripheral collisions, while for the more strongly bound ground state $Υ(1S)$, a significant primordial component survives in central collisions. On the other hand, at RHIC energies, regeneration is overall a smaller effect. Together with effects from nuclear absorption, this offers an explanation for the experimental observation that $Υ(1S)$ production at RHIC and the LHC is of comparable magnitude despite the significantly higher temperatures reached in the QGP at the LHC.
