3.55 keV line in Minimal Decaying Dark Matter scenarios

TL;DR

This paper explores whether simple decaying dark matter models can explain the 3.55 keV X-ray line, analyzing their compatibility with relic density and potential detection at the LHC.

Contribution

It introduces a minimal decaying dark matter scenario involving a scalar field charged under SM gauge interactions, linking astrophysical signals with collider phenomenology.

Findings

Decaying dark matter can produce the 3.55 keV line within certain parameter ranges.

Relic density constraints influence the decay lifetime and collider signatures.

Potential LHC signals depend on the scalar field's properties and decay channels.

Abstract

We investigate the possibility of reproducing the recently reported $3.55\,\mbox{keV}$ line in some simple decaying dark matter scenarios. In all cases a keV scale decaying DM is coupled with a scalar field charged under SM gauge interactions and thus capable of pair production at the LHC. We will investigate how the demand of a DM lifetime compatible with the observed signal, combined with the requirement of the correct DM relic density through the freeze-in mechanism, impacts the prospects of observation at the LHC of the decays of the scalar field.