Flavour-changing Higgs decays into bottom and strange quarks in supersymmetry

TL;DR

This paper investigates flavor-changing Higgs decays into bottom and strange quarks within supersymmetric models, finding potentially observable branching ratios that could signal new physics beyond current collider capabilities.

Contribution

It provides the first detailed analysis of flavor-changing Higgs decays in general supersymmetric scenarios, including the MSSM, highlighting their potential as probes of new physics.

Findings

Branching ratio of the lightest Higgs $H_1$ is about 10^{-6} in MSSM.

Heavy Higgs states can have branching ratios around 10^{-3}.

Extended supersymmetric models can increase $H_1 o bs$ branching ratio to about 10^{-4}.

Abstract

In this work, we explore the flavour changing decays $H_i \to b s$ in a general supersymmetric scenario. In these models, the flavour changing decays arise at loop-level but, originating from a dimension-four operator, do not decouple and may provide a first sign of new physics for heavy masses beyond collider reach. In the framework of the minimal supersymmetric extension of the Standard Model (MSSM), we find that the largest branching ratio of the lightest Higgs ($H_1$) is ${\cal O}(10^{-6})$ after imposing present experimental constraints. While heavy Higgs states may still present branching ratios ${\cal O}(10^{-3})$. In a more general supersymmetric scenario, where additional Higgs states may modify the Higgs mixings, the branching ratio BR($H_1 \to b s$) can reach values ${\cal O}(10^{-4})$ , while heavy Higgses still remain at ${\cal O}(10^{-3})$. Although these values are clearly out of reach for the LHC, a full study in a linear collider environment could be worth pursuing.