Gamma Lines from Majorana Dark Matter

TL;DR

This paper explores models where Majorana dark matter particles produce detectable gamma-ray lines through annihilation, offering a potential method to distinguish dark matter signals from background noise.

Contribution

It introduces simple models with Majorana fermions that have suppressed annihilation into fermions but significant gamma-ray line production, providing a new avenue for dark matter detection.

Findings

Gamma-ray lines are predicted to be detectable from Majorana dark matter annihilation.

Models show velocity-suppressed annihilation into Standard Model fermions.

Unenhanced gamma-ray signals can serve as a distinctive signature for these models.

Abstract

We discuss simple models which predict the existence of significant gamma-ray fluxes from dark matter annihilation. In this context the dark matter candidate is a Majorana fermion with velocity-suppressed tree-level annihilation into Standard Model fermions but unsuppressed annihilation into photons. These gamma lines can easily be distinguished from the continuum and provide a possibility to test these models.