有限温度QCD中树图级散射的高能行为：喷注-介质蒙特卡罗模拟中理论系统不确定性的估计
The high-energy behavior of tree-level scattering in finite-temperature QCD: estimates of theoretical systematic uncertainty in jet-medium Monte Carlo simulations
AI总结：
本研究发现热QCD树图级高能散射与常用近似存在显著偏差，会影响喷注输运系数$\u0026#271;q$，导致现有QGP喷注蒙特卡罗模拟的$\u0026#271;q$约束有偏差，还基于两者差异构建了理论系统不确定性以更新贝叶斯分析的$\u0026#271;q$不确定区间。
AI中文摘要：
我们研究了热量子色动力学（QCD）中树图级散射在高能下的行为，发现其与常用近似方法[Phys. Rev. D 44, 1298 (1991), Phys. Rev. D 44, R2625 (1991), Phys. Rev. D.77, 014015 (2008), Phys. Rev. D. 77.114017 (2008)]存在显著偏差。这些散射率的偏差还会影响部分子层面的喷注-介质输运系数，导致单位长度横动量展宽$\u0026#271;q$的运动学依赖关系发生变化。由于散射率和$\u0026#271;q$被用于夸克胶子等离子体（QGP）中喷注的大规模蒙特卡罗模拟，例如[Phys. Rev. C 111,054913 (2025)]中的工作，目前对$\u0026#271; q$的约束因其中使用的近似而存在偏差。除了在理论上改进$\u0026#271; q$之外，本文得到的$\u0026#271; q$与喷注蒙特卡罗模拟中使用的近似$\u0026#271; q$之间的差异被用于构建理论系统不确定性，该不确定性进而可用于设计$\u0026#271; q$的协方差矩阵，并能够更新通过贝叶斯分析得到的$\u0026#271; q$的不确定性区间。
英文摘要：
We examine the behavior of tree-level scattering in thermal QCD at high energies and find significant deviations away from the commonly used approximations [Phys. Rev. D 44, 1298 (1991), Phys. Rev. D 44, R2625 (1991), Phys. Rev. D.77, 014015 (2008), Phys. Rev. D. 77.114017 (2008)]. These deviations in the scattering rate also affect jet-medium transport coefficients at the partonic level, leading to a different kinematic dependence of the transverse momentum broadening per unit length $\hat{q}$. As scattering rates and $\hat{q}$ are used by large-scale Monte Carlo simulations of jets in the quark-gluon plasma (QGP), such as [Phys. Rev. C 111,054913 (2025)], current constraints on $\hat q$ are biased owing to the approximations used therein. Besides theoretically improving $\hat q$, the differences between the $\hat q$ herein and the approximate $\hat q$ used in jet Monte Carlo simulations are used to construct a theoretical systematic uncertainty, which in turn can be employed to devise a covariance matrix for $\hat q$ and enables updating the uncertainty bands on $\hat q$ obtained by Bayesian analysis.
