A factorization approach to next-to-leading-power threshold logarithms
A factorization approach to next-to-leading-power threshold logarithms
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DOI：
10.1007/jhep06(2015)008
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发表时间：
2015-03
影响因子：
5.4
通讯作者：
Domenico Bonocore;E. Laenen;E. Laenen;L. Magnea;S. Melville;L. Vernazza;Chris D. White
中科院分区：
文献类型：
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作者：
Domenico Bonocore;E. Laenen;E. Laenen;L. Magnea;S. Melville;L. Vernazza;Chris D. White
当选择的最终状态迫使胶子辐射软或共线时，阈值对数在部分子截面中占主导地位。这种辐射在散射振幅水平上因式分解，这导致阈值对数的恢复，出现在阈值变量的领先功率处。在本文中，我们考虑了这种分解的扩展，以包括被阈值变量的单次幂抑制的影响。在Low-Burnett-Kroll-Del Duca （LBKD）定理的基础上，我们提出了将辐射振幅分解为通用构件的方法，其中包含了导致电弱湮灭过程中强子横截面中次优功率（NLP）阈值对数的所有效应。特别是，我们提供了辐射射流函数的NLO评估，负责在这些截面上的次软和共线效应的干扰。作为测试，使用我们的振幅表达式，我们在NNLO Drell-Yan横截面中再现了所有类阿贝尔NLP阈值对数，包括真实和虚拟发射的相互作用。我们的结果是朝着为NLP阈值效应开发一种普遍适用的恢复形式迈出的重要一步，并说明了在环路水平上规范理论振幅的次软定理的分解。
Threshold logarithms become dominant in partonic cross sections when the selected final state forces gluon radiation to be soft or collinear. Such radiation factorizes at the level of scattering amplitudes, and this leads to the resummation of threshold logarithms which appear at leading power in the threshold variable. In this paper, we consider the extension of this factorization to include effects suppressed by a single power of the threshold variable. Building upon the Low-Burnett-Kroll-Del Duca (LBKD) theorem, we propose a decomposition of radiative amplitudes into universal building blocks, which contain all effects ultimately responsible for next-to-leading-power (NLP) threshold logarithms in hadronic cross sections for electroweak annihilation processes. In particular, we provide a NLO evaluation of the radiative jet function, responsible for the interference of next-to-soft and collinear effects in these cross sections. As a test, using our expression for the amplitude, we reproduce all abelian-like NLP threshold logarithms in the NNLO Drell-Yan cross section, including the interplay of real and virtual emissions. Our results are a significant step towards developing a generally applicable resummation formalism for NLP threshold effects, and illustrate the breakdown of next-to-soft theorems for gauge theory amplitudes at loop level.