NNLO predictions with nonlocal subtractions and fiducial power corrections in GENEVA

Abstract: We present the implementation of next-to-next-to-leading order (NNLO) QCD fully-differential corrections within the GENEVA framework, for both colour-singlet and colour-singlet+jet processes at hadron colliders, by employing a nonlocal subtraction approach. In particular, we discuss the implementation details and the challenges that arise when utilizing a dynamical infrared cutoff parameter. Additionally, we combine the subtraction with the projection-to-Born method in order to include fiducial power corrections. As a test case, we provide predictions for Drell-Yan and $Z$+jet production at the LHC, using $N$-jettiness as resolution variable. We validate the NNLO corrections of GENEVA against NNLOJET finding excellent agreement. Finally, we discuss how to extend our method to calculate the N$^3$LO QCD fully-differential corrections to colour-singlet production at hadron colliders.