Indirect searches for dark matter bound state formation and level transitions

TL;DR

This paper explores how dark matter can form bound states and transition between levels, providing new indirect detection signals and tighter constraints using gamma-ray observations.

Contribution

It extends indirect dark matter searches to include bound state formation and transitions, refining predicted signals and applying constraints from Fermi-LAT data.

Findings

Significantly refined predicted gamma-ray signals from dark matter bound states.

Derived constraints on dark photon mass and energy from dwarf spheroidal observations.

Provided new limits on dark matter models involving bound state formation.

Abstract

Indirect searches for dark matter (DM) have conventionally been applied to the products of DM annihilation or decay. If DM couples to light force carriers, however, it can be captured into bound states via dissipation of energy that may yield detectable signals. We extend the indirect searches to DM bound state formation and transitions between bound levels, and constrain the emission of unstable dark photons. Our results significantly refine the predicted signal flux that could be observed in experiments. As a concrete example, we use Fermi-LAT dwarf spheroidal observations to obtain constraints in terms of the dark photon mass and energy which we use to search for the formation of stable or unstable bound states.