Momentum-dependent two-loop QCD corrections to the neutral Higgs-boson masses in the MSSM

TL;DR

This paper calculates momentum-dependent two-loop QCD corrections to the MSSM Higgs boson masses, improving the precision of theoretical predictions and reducing uncertainties in the lightest Higgs mass estimate.

Contribution

It introduces a novel calculation of momentum-dependent two-loop corrections in the MSSM Higgs sector using a mixed on-shell/DRbar scheme, integrated into FeynHiggs.

Findings

Mass shifts below 1 GeV for the lightest Higgs in all scenarios

Enhanced accuracy in Higgs mass predictions

Reduced theoretical uncertainty in MSSM Higgs mass calculations

Abstract

Results are presented for the momentum dependent two-loop contributions of O(alpha_t alpha_s) to the masses and mixing effects in the Higgs sector of the MSSM. They are obtained in the Feynman-diagrammatic approach using a mixed on-shell/DRbar renormalization that can directly be matched onto the higher-order corrections included in the code FeynHiggs. The new two-loop diagrams are evaluated with the program SecDec. The combination of the new momentum dependent two-loop contribution with the existing one- and two-loop corrections in the on-shell/DRbar scheme leads to an improved prediction of the light MSSM Higgs boson mass and a correspondingly reduced theoretical uncertainty. We find that the corresponding shifts in the lightest Higgs-boson mass M_h are below 1 GeV in all scenarios considered, but can extend up to the level of the current experimental uncertainty. The results are included in the code FeynHiggs.