We consider the double-soft limit of QCD amplitudes with two massive quarks in a back-to-back kinematics accompanied by two soft partons. We integrate analytically the respective double-soft eikonal functions over the phase space of the two soft partons. Within the context of the nested soft-collinear subtraction scheme, our results may serve as one of the integrated subtraction terms needed for the analytic and fully-differential description of next-to-next-to-leading order (NNLO) QCD corrections to colour-singlet decay into massive partons or to heavy-quark pair production.

中文翻译：

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背靠背运动学中两个大质量发射器的解析双软积分减法项

我们在背靠背运动学中考虑了 QCD 振幅的双软极限，其中两个大质量夸克伴随着两个软子。我们在两个软部分的相空间上对各自的双软特征函数进行了分析整合。在嵌套的软共线减法方案的背景下，我们的结果可以作为对颜色的紧邻次前导序 (NNLO) QCD 校正的分析和全微分描述所需的集成减法项之一- 单重衰变成大质量子或重夸克对的产生。