Three-Loop Gluon Scattering in QCD and the Gluon Regge Trajectory.
Physical review letters 128:21 (2022) 212001
Abstract:
We compute the three-loop helicity amplitudes for the scattering of four gluons in QCD. We employ projectors in the 't Hooft-Veltman scheme and construct the amplitudes from a minimal set of physical building blocks, which allows us to keep the computational complexity under control. We obtain relatively compact results that can be expressed in terms of harmonic polylogarithms. In addition, we consider the Regge limit of our amplitude and extract the gluon Regge trajectory in full three-loop QCD. This is the last missing ingredient required for studying single-Reggeon exchanges at next-to-next-to-leading logarithmic accuracy.Investigating the universality of five-point QCD scattering amplitudes at high energy
Journal of High Energy Physics Springer 2025:3 (2025) 129
Abstract:
We investigate 2 → 3 QCD scattering amplitudes in multi-Regge kinematics, i.e. where the final partons are strongly ordered in rapidity. In this regime amplitudes exhibit intriguing factorisation properties which can be understood in terms of effective degrees of freedom called reggeons. Working within the Balitsky/JIMWLK framework, we predict these amplitudes for the first time to next-to-next-to-leading logarithmic order, and compare against the limit of QCD scattering amplitudes in full colour and kinematics. We find that the latter can be described in terms of universal objects, and that the apparent non-universality arising at NNLL comes from well-defined and under-control contributions that we can predict. Thanks to this observation, we extract for the first time the universal vertex that controls the emission of the central-rapidity gluon, both in QCD and N = 4 super Yang-Mills.Finite Feynman integrals
Physical Review D American Physical Society (APS) 110:11 (2024) 116026
Five-parton scattering in QCD at two loops
Physical Review D American Physical Society (APS) 109:9 (2024) 094025
Three-loop helicity amplitudes for photon+jet production
Physical Review D American Physical Society (APS) 107:5 (2023) l051502