Enhancing $h \to \gamma \gamma$ with staus in SUSY models with extended gauge sector

TL;DR

This paper explores how additional D-terms in U(1)-extended MSSM models can enhance the Higgs to diphoton decay rate via staus, while also satisfying relic density and LEP excess constraints.

Contribution

It demonstrates that U(1)-extended MSSM models can naturally enhance the Higgs diphoton decay rate through D-term contributions to stau masses, even with universal scalar and gaugino masses.

Findings

Enhanced diphoton decay rate achievable in B-L-SSM

Viable lighter scalar fitting LEP excess

Correct relic density for LSP in constrained scenario

Abstract

We discuss the impact on the stau masses of the additional D-terms in U(1)-extended MSSM models. We show, explicitly for the B-L-SSM, that these contributions can play a crucial role in the explanation of the enhanced diphoton decay rate of a SM-like Higgs particle around 125 GeV. Even in the most constrained scenario with universal scalar and gaugino masses, it is possible to obtain a sizable enhancement and, in addition, the correct relic density for the LSP. Furthermore, a lighter CP-even scalar that could fit the LEP excess at 98 GeV is viable.