[HET Lunch Discussion] Two-Loop QCD Corrections for Three-Photon Production at Hadron Colliders

by Samuel Abreu (CERN)

Friday 5 May 2023, 12:30 → 14:00 US/Eastern

2-160 (https://bnl.zoomgov.com/j/1606326508?pwd=dTJPb25nWnJPMmdMNGZLQnUyV2ViZz09)

I will discuss the calculation of the complete two-loop QCD corrections for the production of three photons at the LHC, including subleading colour contributions. The two-loop numerical unitarity approach used previously for the planar contributions is extended to handle five-point non-planar topologies. Analytic expressions for the two-loop remainders are reconstructed and simplified using spinor-helicity variables. The analytic results we obtain are found to be numerically stable and rarely require muti-precision recovery strategies. Finally, we explore the numerical size of the subleading-color contribution to the two-loop hard functions, and find them to be potentially relevant to achieve theoretical predictions at the 1% precision level.

 

Hybrid event