Nested soft-collinear subtractions for NNLO calculations
Raoul Röntsch · 2018
I present a subtraction scheme for next-to-next-to-leading order (NNLO) QCD calculations, based on the residue-improved sector decomposition method. The subtraction scheme is characterized by the independent treatment of soft and collinear limits, leading to a straightforward procedure to remove singularities using nested subtractions. The scheme is fully local and results in relatively compact expressions for the singularities, allowing the cancellation of the poles to be checked explicitly. Following this, all matrix elements may be evaluated in four dimensions. I present some of the details of the subtraction scheme applied to color singlet production at NNLO QCD, based on the work of Ref. [1]. I also present results from a proof-of-concept calculation and comparison, showing that the subtraction scheme is capable of delivering numerically stable results for NNLO QCD calculations.