Dipole subtraction at next-to-leading order in nonrelativistic-QCD factorization

TL;DR

This paper presents a detailed implementation of a dipole subtraction scheme for NLO calculations in nonrelativistic QCD, specifically addressing heavy-quarkonium production with S- and P-wave states, extending existing methods to handle complex divergence structures.

Contribution

It introduces a novel extension of dipole subtraction to nonrelativistic QCD for heavy-quarkonium, including P-wave states with intricate infrared divergences.

Findings

Successful implementation of subtraction scheme for S- and P-wave states

Enhanced handling of infrared divergences in P-wave quarkonium production

Framework applicable to NLO calculations in heavy-quarkonium physics

Abstract

We describe an implementation of a subtraction scheme in the nonrelativistic-QCD treatment of heavy-quarkonium production at next-to-leading-order in the strong-coupling constant, covering $S$- and $P$-wave bound states. It is based on the dipole subtraction in the massless version by Catani and Seymour and its extension to massive quarks by Phaf and Weinzierl. Important additions include the treatment of heavy-quark bound states, in particular due to the more complicated infrared-divergence structure in the case of $P$-wave states.