$gg \to ZH$ : updated predictions at NLO QCD

TL;DR

This paper provides advanced NLO QCD predictions for gluon-initiated ZH production at the LHC, reducing theoretical uncertainties and including top-mass scheme effects.

Contribution

It introduces a novel combination of forward and high-energy expansions for virtual corrections, improving the accuracy of NLO predictions for $gg o ZH$.

Findings

Scale uncertainties reduced to 15%

Virtual corrections validated against full numerical results

Includes top-mass scheme uncertainty estimate

Abstract

We present state-of-the-art predictions for the inclusive cross section of gluon-initiated $ZH$ production, following the recommendations of the LHC Higgs Working Group. In particular, we include NLO QCD corrections, where the virtual corrections are obtained from the combination of a forward expansion and a high-energy expansion, and the real corrections are exact. The expanded results for the virtual corrections are compared in detail to full numerical results. The updated predictions show a reduction of the scale uncertainties to the level of 15%, and they include an estimate of the top-mass-scheme uncertainty.