On the NLO QCD corrections to Higgs production and decay in the MSSM

TL;DR

This paper provides explicit two-loop QCD correction formulas for Higgs production and decay in the MSSM, using approximations valid for light Higgs bosons, enhancing precision in theoretical predictions.

Contribution

It offers new analytic results for two-loop top/stop/gluino contributions in MSSM Higgs production, employing a low-energy theorem adapted for particle mixing.

Findings

Gluino contribution is well approximated by the zero Higgs mass limit for the lightest Higgs.

The approximation's validity is confirmed through an expansion in Higgs mass powers.

Results include two-loop QCD corrections to Higgs decay into photons.

Abstract

We present explicit analytic results for the two-loop top/stop/gluino contributions to the cross section for the production of CP-even Higgs bosons via gluon fusion in the MSSM, under the approximation of neglecting the Higgs boson mass with respect to the masses of the particles circulating in the loops. The results are obtained employing the low-energy theorem for Higgs interactions adapted to the case of particle mixing. We discuss the validity of the approximation used by computing the first-order correction in an expansion in powers of the Higgs boson mass. We find that, for the lightest CP-even Higgs boson, the gluino contribution is very well approximated by the result obtained in the limit of vanishing Higgs mass. As a byproduct of our calculation, we provide results for the two-loop QCD contributions to the photonic Higgs decay.