An update on the two singlet Dark Matter model

TL;DR

This paper revisits a two-singlet scalar extension of the Standard Model, analyzing its viability as a dark matter model under current experimental constraints, and explores its potential to explain the galactic center gamma-ray excess.

Contribution

It provides a comprehensive analysis of the two-singlet dark matter model with updated experimental constraints and investigates its ability to account for the gamma-ray excess.

Findings

Xenon1T bounds restrict parameter space

Relic abundance achieved via Breit-Wigner enhancement

Model can explain gamma-ray excess with 36-51 GeV dark matter

Abstract

We revisit the two real singlet extension of the Standard Model with a $Z_2\times Z_2^\prime$ symmetry. One of the singlet scalars $S_2$, by virtue of an unbroken $Z_2^\prime$ symmetry, plays the role of a stable dark matter candidate. The other scalar $S_1$, with spontaneously broken $Z_2$-symmetry, mixes with the SM Higgs boson and acts as the scalar mediator. We analyze the model by putting in the entire set of theoretical and recent experimental constraints. The latest bounds from direct detection Xenon1T experiment severely restricts the allowed region of parameter space of couplings. To ensure the dark matter satisfies the relic abundance criterion, we rely on the Breit-Wigner enhanced annihilation cross-section. Further, we study the viability of explaining the observed gamma-ray excess in the galactic center in this model with a dark matter of mass in the $\sim 36-51$ GeV window and present our conclusions.