Theory Seminar

Nested soft-collinear subtraction and analytic double-unresolved subtraction terms

by Delto Maximilian

313 (MPI Meeting rooms)


MPI Meeting rooms

In recent years, theoretical predictions at next-to-next-to-leading-order in perturbative QCD appeared for an impressive number of hard processes at the LHC. Despite this success, the extension to more complex processes will require significant improvements in methods of two-loop calculations and the development of more efficient and transparent subtraction schemes to handle infrared divergences. In this talk, I introduce the recently proposed nested soft-collinear subtraction scheme, which is an attempt to streamline the residue-improved sector subtraction scheme. Although the latter is already modular, completely general and fully-local, explicit separation of soft and collinear divergences leads to a reduced number of subtraction terms and a more transparent and physically appealing subtraction picture. In the second part of this talk, I will discuss how the analytic integration of the two double-unresolved subtraction terms, the double-soft and the triple-collinear, is performed by means of reverse unitarity. These results enabled the analytic formulation of fully-differential color-singlet production in gluon-gluon and quark-antiquark annihilation through NNLO QCD.