Five-Parton Scattering in QCD at Two Loops

Abstract

We compute all helicity amplitudes for the scattering of five partons in two-loop QCD in all the relevant flavor configurations, retaining all contributing color structures. We employ tensor projection to obtain helicity amplitudes in the 't Hooft-Veltman scheme starting from a set of primitive amplitudes. Our analytic results are expressed in terms of massless pentagon functions, and are easy to evaluate numerically. These amplitudes provide important input to investigations of collinear-factorization breaking and to studies of the multi-Regge kinematics regime.

Comments: fixed typos in Eqs.(8,9) and Table 1; updated numerical results in Table 2; analytic results unchanged; extended examples in the repository at https://zenodo.org/records/10227683