Double-real radiation in hadronic top quark pair production as a proof of a certain concept

Understand

Using the recently introduced STRIPPER approach to double-real radiation, we evaluate the total cross sections for the main partonic channels of the next-to-next-to leading order contributions to top quark pair production in hadronic collisions: gg -> ttgg, gg -> ttqq, qq -> ttgg, qq -> ttq'q', q' != q.

• The results are given as Laurent expansions in epsilon, the parameter of dimensional regularization, at a number of m/ECM values spreading the entire variation range, with m the mass of the top quark and ECM the center-of-mass energy.
• We describe the details of our implementation and demonstrate its main properties: pointwise convergence and efficiency.
• We also prove the cancellation of leading divergences after inclusion of the double-virtual and real-virtual contributions.