论文标题
NNLO的全差异Gluon束功能
The Fully-Differential Gluon Beam Function at NNLO
论文作者
论文摘要
完全差异的光束函数（DBF）是对强子对撞机可观察物的重新预测的通用成分，可探测每个碰撞质子的传入parton的全动力学 - 虚拟和横向动量以及轻度的动量分数$ x $。在本文中，我们按两环阶在非偏振的Gluon DBF和通常的Parton分布函数（PDFS）之间计算匹配系数。对于探测传入元素的虚拟和横向动量的可观察结果，我们的结果提供了与共线初始状态辐射相关的NNLO单数横截面的一部分，并且是通过N $^3 $ LL重新点亮大对数所必需的。除此之外，DBF通过简单的集成与阈值分解的广义版本中出现的光束函数紧密相关。通过对两环gluon匹配系数执行此整合，我们还获得了广义阈值梁函数的相应量。
The fully-differential beam function (dBF) is a universal ingredient in resummed predictions of hadron collider observables that probe the full kinematics of the incoming parton from each colliding proton -- the virtuality and transverse momentum as well as the light-cone momentum fraction $x$. In this paper we compute the matching coefficients between the unpolarized gluon dBF and the usual parton distribution functions (PDFs) at the two-loop order. For observables probing both the virtuality and transverse momentum of incoming gluons, our results provide the part of the NNLO singular cross section related to collinear initial-state radiation, and are required for the resummation of large logarithms through N$^3$LL. Further to this, the dBF is closely linked to the beam function appearing in a generalized version of threshold factorization, via a simple integration. By performing this integration for the two-loop gluon matching coefficients, we also obtain the corresponding quantities for the generalized threshold beam function.
