CWebGen -- A tool to study colour structure of scattering amplitudes in IR limit

Infrared singularities in perturbative Quantum Chromodynamics (QCD) are captured by the Soft function, which can be calculated efficiently in terms of multiparton webs. Web is a closed set of diagrams whose colour and kinematics mix through a web mixing matrix. The web mixing matrices are computed using a well known replica trick algorithm. We present a package implemented in Mathematica to calculate these mixing matrices. Along with the package, we provide benchmark points for several state-of-the art computations.微扰量子色动力学（Quantum Chromodynamics，QCD）中的红外奇点可由软函数（Soft function）刻画，而软函数可借助多部分子网（multiparton webs）实现高效计算。多部分子网是一类闭合费曼图的集合，其色自由度与运动学自由度可通过网混合矩阵（web mixing matrix）发生混合。网混合矩阵可通过广为人知的复本技巧算法（replica trick algorithm）进行计算。本文开发了一款基于Mathematica的软件包，用于计算上述网混合矩阵。随该软件包一同提供的，还有若干前沿计算对应的基准测试点。