MeV Gamma-Ray Constraints for Light Dark Matter from Semi-Annihilation

TL;DR

This paper investigates constraints on light dark matter (1 MeV to 1 GeV) produced via semi-annihilation, using gamma-ray data from multiple space telescopes to explore the parameter space and future detection prospects.

Contribution

It introduces a novel analysis of semi-annihilating light dark matter using MeV gamma-ray data, providing new bounds and future detection potential.

Findings

EGRET data imposes stringent constraints on semi-annihilation cross-sections.

e-ASTROGAM can potentially probe the entire parameter space of the model.

Gamma-ray observations are crucial for understanding light dark matter properties.

Abstract

Exploring the realm of Dark Matter research, Light DM, which has a mass in the range of 1 MeV to 1 GeV, is a fascinating topic both theoretically and experimentally. We assume that the light dark matter is composed of complex scalars and produced from semi-annihilation, which is close to the scale of the MeV Gamma-ray satellite, allowing us to explore the implications of this hypothesis. The experimental data we used to constrain the scenario is from five different sources: the COMPTEL, EGRET, INTEGRAL, Fermi Gamma-ray Space Telescope, and the e-ASTROGAM future reach. We use the analytical formula to measure the X-ray spectra allowing us to determine the annihilation cross-section bounds from $10^{-28}\mathrm{cm}^3/\mathrm{s}$ to $10^{-22}\mathrm{cm}^3/\mathrm{s}$ for different combinations of dark matter and mediator masses. We found that the MeV gamma-ray provides valuable insight into the structure of the semi-annihilation dark matter, where EGRET contributes to the stringent constraint to the semi-annihilation, and the e-ASTROGAM future reach could probe the whole parameter space of the model.