Three-loop helicity amplitudes for quark-gluon scattering in QCD

Abstract

Abstract We compute the three-loop helicity amplitudes for q q ¯ $$ q\overline{q} $$ → gg and its crossed partonic channels, in massless QCD. Our analytical results provide a non-trivial check of the color quadrupole contribution to the infrared poles for external states in different color representations. At high energies, the qg → qg amplitude shows the predicted factorized form from Regge theory and confirms previous results for the gluon Regge trajectory extracted from qq′ → qq′ and gg → gg scattering.

Keywords

• Higher-Order Perturbative Calculations
• Scattering Amplitudes
• Specific QCD Phenomenology