Hybrid calculation of the MSSM Higgs boson masses using the complex THDM as EFT

Abstract

Recently, the Higgs boson masses in the Minimal supersymmetric standard model (MSSM) and their mixing have been calculated using the complex two-Higgs-doublet model (cTHDM) as an effective field theory (EFT) of the MSSM. Here, we discuss the implementation of this calculation, which we improve in several aspects, into the hybrid framework of FeynHiggs by combing the cTHDM-EFT calculation with the existing fixed-order calculation. This combination allows accurate predictions also in the intermediate regime where some SUSY particles are relatively light, some relatively heavy and some in between. Moreover, the implementation provides precise predictions for the Higgs decay rates and production cross-sections.