Indirect detection constraints on semi-annihilation of inert scalar multiplets

TL;DR

This paper investigates how semi-annihilation processes in inert scalar multiplet models affect indirect dark matter detection constraints, showing certain models remain viable under various galactic density assumptions.

Contribution

It provides the first detailed analysis of indirect detection constraints on semi-annihilation in inert scalar multiplet models, highlighting conditions for compatibility with observations.

Findings

Dark matter can be thermally produced and consistent with constraints for specific gauge numbers.

Semi-annihilation modifies indirect detection signals, easing some observational constraints.

Viability depends on galactic dark matter density profiles.

Abstract

Certain models of inert multiplets allow for semi-annihilation processes, in which two dark matter candidates annihilate to a dark matter particle and a non-dark matter particle. The existence of these processes can alleviate certain constraints and substantially modify the indirect detection signal. In this paper, we study current indirect detection constraints on the semi-annihilation of inert scalar multiplets. We show that there exist gauge numbers for which dark matter can be thermally produced and be compatible with indirect detection constraints even for very cuspy galactic dark matter density profiles.