An alternative subtraction scheme for next-to-leading order QCD calculations

Abstract

We propose a new subtraction scheme for next-to-leading order QCD calculations. Our scheme is based on the momentum mapping and on the splitting functions derived in the context of an improved parton shower formulation. Compared to standard schemes, the new scheme features a significantly smaller number of subtraction terms and facilitates the matching of NLO calculations with parton showers including quantum interference. We provide formulae for the momentum mapping and the subtraction terms, and present a detailed comparison with the Catani-Seymour dipole subtraction for a variety of 2 -> 2 scattering processes.