Pseudoscalar Higgs boson decay to three parton amplitudes at NNLO to higher orders in the dimensional regulator

TL;DR

This paper calculates second-order corrections for pseudo-scalar Higgs decay into three partons at NNLO, enhancing precision in theoretical predictions for collider experiments.

Contribution

It provides the first computation of two-loop amplitudes for pseudo-scalar Higgs decay to three partons at higher orders in the dimensional regulator.

Findings

Computed one and two-loop amplitudes for $A\to ggg$ and $A\to q\bar{q}g$

Results enable more accurate predictions of Higgs plus jet distributions at NNLO

Implemented finite amplitude pieces in a numerical code for collider simulations

Abstract

We present for the first time the second-order corrections of pseudo-scalar($A$) Higgs decay to three parton to higher orders in the dimensional regulator. We compute the one and two-loop amplitudes for processes, $A\to ggg$ and $A\to q\bar{q}g$ in the effective theory framework. With suitable crossing of the external momenta, these calculations are well-suited for predicting the differential distribution of pseudo-scalar Higgs in association with a jet at hadron colliders, up to next-to-next-to-leading order (NNLO) in the strong coupling constant. These results expanded to higher orders in dimensional regulator will contribute to the full three loop cross section. We implement the finite pieces of the amplitudes in a numerical code which can be used with any Monte Carlo phase space generator.