Finite fermion mass effects in pseudoscalar Higgs production via gluon-gluon fusion

TL;DR

This paper calculates the leading logarithmic behavior of pseudoscalar Higgs production via gluon fusion, including finite fermion mass effects and rapidity distribution, up to NNLO accuracy.

Contribution

It provides the first all-orders leading logarithmic calculation including top and bottom quark contributions with interference effects for pseudoscalar Higgs production.

Findings

Finite fermion mass effects are small, only a few percent for large pseudoscalar masses.

Results improve the NNLO inclusive cross-section calculations in the effective theory.

Explicit evaluation of integrals up to NNLO enhances precision of theoretical predictions.

Abstract

We compute the leading logarithmic behaviour of the cross-section for the production of a pseudoscalar Higgs boson in gluon-gluon fusion to all-orders in perturbation theory, in the limit of large partonic centre of mass energy. We also calculate the Higgs rapidity distribution to the same accuracy. We include the contributions of top and bottom quarks, together with their interference. Our results are given in terms of single and double integrals, evaluated explicitly up to next-to next-to leading order (NNLO). We use our results to improve the known NNLO inclusive cross-section computed in the effective theory where the fermions in the loop are integrated out. The size of finite fermion mass effects on the inclusive cross-section is found to be small, reaching a few percent only for large values of the pseudoscalar mass.