Soft and Collinear Functions for the Standard Model

TL;DR

This paper derives universal soft and collinear functions for all Standard Model particles, providing explicit formulas for various scattering processes and discussing subtleties in applying the Goldstone boson equivalence theorem.

Contribution

It presents the first comprehensive set of collinear functions for all Standard Model particles and explicit soft function expressions for key scattering processes.

Findings

Explicit soft functions for fermion-fermion scattering

Collinear functions for all Standard Model particles

Discussion of Goldstone boson equivalence theorem subtleties

Abstract

Radiative corrections to high energy scattering processes were given previously in terms of universal soft and collinear functions. This paper gives the collinear functions for all standard model particles, the general form of the soft function, and explicit expressions for the soft functions for fermion-fermion scattering, longitudinal and transverse gauge boson production, single W/Z production, and associated Higgs production. An interesting subtlety in the use of the Goldstone boson equivalence theorem for longitudinal W+ production is discussed.