The Higgs sector of the complex MSSM at two-loop order: QCD contributions

TL;DR

This paper calculates two-loop QCD corrections to the Higgs sector in the complex MSSM, revealing significant phase-dependent shifts in the lightest Higgs boson mass.

Contribution

It provides the first comprehensive two-loop QCD correction analysis including all complex phases in the MSSM Higgs sector using on-shell renormalization.

Findings

Two-loop corrections can shift the Higgs mass by up to 5 GeV.

Phase variations in the scalar top sector significantly affect Higgs mass predictions.

Full dependence on complex phases enhances the accuracy of MSSM Higgs mass calculations.

Abstract

Results are presented for the leading two-loop contributions of O(alpha_t alpha_s) to the masses and mixing effects in the Higgs sector of the MSSM with complex parameters. They are obtained in the Feynman-diagrammatic approach using on-shell renormalization. The full dependence on all complex phases is taken into account. The renormalization of the appropriate contributions of the Higgs-boson sector and the scalar top and bottom sector is discussed. Our numerical analysis for the lightest MSSM Higgs-boson mass is based on the new two-loop corrections, supplemented by the full one-loop result. The corrections induced by the phase variation in the scalar top sector are enhanced by the two-loop contributions. We find that the corresponding shift in M_h1 can amount to 5 GeV.