Forward Higgs production within high energy factorization in the heavy quark limit at next-to-leading order accuracy

TL;DR

This paper calculates next-to-leading order corrections to forward Higgs production using high energy factorization and Lipatov's effective action, providing a stable method to handle infra-red singularities in the heavy quark limit.

Contribution

It introduces a proper definition and subtraction mechanism for NLO coefficients within high energy effective action, extending previous prescriptions and enabling better phenomenological and theoretical analysis.

Findings

Derived NLO corrections for Higgs production in the high energy limit.

Proposed a subtraction method for infra-red singularities with off-shell legs.

Enhanced framework for transverse momentum dependent factorization at high energies.

Abstract

We use Lipatov's high energy effective action to determine the next-to-leading order corrections to Higgs production in the forward region within high energy factorization making use of the infinite top mass limit. Our result is based on an explicit calculation of real corrections combined with virtual corrections determined earlier by Nefedov. As a new element we provide a proper definition of the desired next-to-leading order coefficient within the high energy effective action framework, extending a previously proposed prescription. We further propose a subtraction mechanism to achieve for this coefficient a stable cancellation of real and virtual infra-red singularities in the presence of external off-shell legs. Apart from its relevance for direct phenomenological studies, such as high energy resummation of Higgs + jet configurations, our result will be further of use for the study of transverse momentum dependent factorization in the high energy limit.