论文标题
Quark对与Gluon相关的Quark对的柔软柔软排放
Tree-level soft emission of a quark pair in association with a gluon
论文作者
论文摘要
我们计算了树级电流，以与gluon合成的软夸克式群岛对发射。这种软电流是了解在QCD中近代到接头到领先订单（n $^3 $ lo）计算中可能出现的红外奇异性的最后缺少成分。它的正方形使我们能够首次理解夸克对和gluon的软发射引起的颜色相关性。我们发现有三种类型的相关性：除了已经出现在树级振幅的软限制的偶极型相关性外，我们首次发现了涉及完全对称结构常数的三方相关性。我们还研究了三重柔软限制中的共线分裂振幅的行为，并得出了相应的分解公式。
We compute the tree-level current for the emission of a soft quark-antiquark pair in association with a gluon. This soft current is the last missing ingredient to understand the infrared singularities that can arise in next-to-next-to-next-to-leading-order (N$^3$LO) computations in QCD. Its square allows us to understand for the first time the colour correlations induced by the soft emission of a quark pair and a gluon. We find that there are three types of correlations: Besides dipole-type correlations that have already appeared in soft limits of tree-level amplitudes, we uncover for the first time also a three-parton correlation involving a totally symmetric structure constant. We also study the behaviour of collinear splitting amplitudes in the triple-soft limit, and we derive the corresponding factorisation formula.
