130 GeV gamma ray line and enhanced Higgs di-photon rate from Triplet-Singlet extended MSSM

TL;DR

This paper presents an extension of the MSSM with a singlet and triplet to explain the 125 GeV Higgs, the 130 GeV gamma-ray line, and enhanced Higgs diphoton decay, consistent with dark matter constraints.

Contribution

It introduces a minimal supersymmetric extension with a singlet and triplet that simultaneously explains multiple experimental observations.

Findings

Achieves the 130 GeV gamma-ray line via resonant dark matter annihilation.

Explains the enhanced Higgs diphoton decay rate through light chargino loops.

Maintains consistency with dark matter relic density and direct detection limits.

Abstract

We propose an economic extension of minimal supersymmetric standard model with a SU(2) singlet and Y=0 triplet, which can explain (i) the 125 GeV Higgs boson without fine tuning, (ii) the 130 GeV $\gamma$-ray line seen at Fermi-LAT, (as well as a second photon line at 114 GeV)(iii) an enhanced Higgs di-photon decay rate seen by ATLAS, while being consistent with dark matter relic density and recent XENON 100 exclusion limits on spin-independent direct detection cross-section. We obtain the required cross-section of $10^{-27}cm^3s^{-1}$ for the 130 GeV $\gamma$-ray flux through the resonant annihilation of dark matter via pseudoscalar triplet Higgs of mass $\sim$260 GeV. The dark matter is predominantly bino-higgsino which has large couplings with photons (through higgsino) and gives correct relic density (through bino). We get the enhanced Higgs diphoton decay rate, $R_{\gamma \gamma}\simeq 1.24$ dominantly contributed by the light chargino-loops, which can account for the reported excess seen in the $h\rightarrow \gamma \gamma$ channel by ATLAS.