论文标题
beam功能$ n $ - jettiness在n $^3 $ lo intttutative qcd
Beam functions for $N$-jettiness at N$^3$LO in perturbative QCD
论文作者
论文摘要
我们介绍了$ n $ jettiness beam功能的所有匹配系数在近代到接头订单（n $^3 $ lo）的扰动量子量子染色体动力学（QCD）的计算。我们的计算是从相应的共线分裂内核开始的，我们使用轴向仪集成。我们使用反向单位性将相关的相位积分映射到循环积分，这使我们能够采用多环技术，包括逐个部分的集成身份和微分方程。我们找到一个规范的基础，并使用算法在所得的主积分之间建立非平凡的部分分数关系，这使我们能够大大减少其数量。通过使用规律条件，我们以独立集的方式表达所有必要的边界常数，我们通过在软限制中直接整合相应的积分来计算。通过这种方式，我们提供了以前在Arxiv：2006.03056中计算的匹配系数的完全独立的计算。
We present a calculation of all matching coefficients for $N$-jettiness beam functions at next-to-next-to-next-to-leading order (N$^3$LO) in perturbative quantum chromodynamics (QCD). Our computation is performed starting from the respective collinear splitting kernels, which we integrate using the axial gauge. We use reverse unitarity to map the relevant phase-space integrals to loop integrals, which allows us to employ multi-loop techniques including integration-by-parts identities and differential equations. We find a canonical basis and use an algorithm to establish non-trivial partial fraction relations among the resulting master integrals, which allows us to reduce their number substantially. By use of regularity conditions, we express all necessary boundary constants in terms of an independent set, which we compute by direct integration of the corresponding integrals in the soft limit. In this way, we provide an entirely independent calculation of the matching coefficients which were previously computed in arXiv:2006.03056.
