$SU(2)\otimes SU(2)$ Gauge Extensions of the MSSM Revisited

TL;DR

This paper explores an extension of the MSSM with an additional gauge group, affecting Higgs properties and potentially explaining a 125 GeV Higgs with specific phenomenological features.

Contribution

It revisits the $SU(2)_1\otimes SU(2)_2$ gauge extension of the MSSM, analyzing its impact on Higgs phenomenology and electroweak constraints, highlighting new parameter space regions.

Findings

Enhanced Higgs decay to gamma gamma possible.

Model accommodates 125 GeV Higgs with light third-generation squarks.

Modified Higgs quartic coupling affects electroweak precision constraints.

Abstract

We study an extension of the Minimal Supersymmetric Standard Model with a gauge group $SU(2)_1\otimes SU(2)_2$ breaking to $SU(2)_L$. The extra wino has an enhanced gauge coupling to the SM-like Higgs boson and, if light, has a relevant impact on the weak scale phenomenology. The low energy Higgs quartic coupling is modified both by extra $D$-term corrections and by a modification of its renormalization group evolution from high energies. At low values of $\tan\beta$, the latter effect may be dominant. This leads to interesting regions of parameter space in which the model can accommodate a 125 GeV Higgs with relatively light third generation squarks and an increased $h \rightarrow \gamma \gamma$ decay branching ratio, while still satisfying the constraints from electroweak precision data and Higgs vacuum stability.