Higgs-bosons couplings to quarks and leptons in the supersymmetric Standard Model with a gauge singlet

TL;DR

This paper calculates loop corrections to Higgs boson couplings to quarks and leptons in a supersymmetric Standard Model extended by a gauge singlet, with implications for flavor physics and Higgs phenomenology.

Contribution

It provides analytic expressions for effective Higgs couplings including sfermion loop effects and complete resummation of chirally-enhanced contributions in a singlet-extended SUSY model.

Findings

Loop corrections significantly affect Higgs-fermion couplings.

Results are relevant for scenarios with small singlet-doublet mixing.

Impacts flavor-changing processes such as ΔF=2.

Abstract

The loop corrections to the couplings of Higgs bosons to quarks and charged leptons are calculated within supersymmetric versions of the Standard Model, extended by a gauge singlet. The effective couplings of the $SU(2)_L$ doublet and singlet Higgs bosons to quarks and leptons, induced by sfermion loops, are derived. Analytic expressions for the case of generic sfermion flavour mixing, including the complete resummation of all chirally-enhanced contributions are presented. These results are important in scenarios in which the mixing between singlet and doublet components of Higgs bosons is small, and the (pseudo) scalar component of the doublet is light. The calculated loop effects can have important consequences in flavour physics, especially for $\Delta F=2$ processes.