# Ruling out $\sim 100-300$ GeV thermal relic annihilating dark matter by radio observation of the Andromeda galaxy

## TL;DR

This study uses radio observations of the Andromeda galaxy to set new constraints on the mass of thermal relic annihilating dark matter, excluding masses between 100-300 GeV for multiple channels and challenging WIMP models.

## Contribution

The paper provides the first constraints on 100-300 GeV dark matter from Andromeda radio data, surpassing previous limits and impacting WIMP thermal production models.

## Key findings

- Excludes 100-300 GeV dark matter for ten annihilation channels.
- Sets lower mass limits above 330 GeV, improving previous constraints.
- Disfavors WIMP thermal freeze-out as the sole dark matter production mechanism.

## Abstract

In the past few years, some studies claimed that annihilating dark matter with mass $\sim 10-100$ GeV can explain the GeV gamma-ray excess in our Galaxy. However, recent analyses of the Fermi-LAT and radio observational data rule out the possibility of the thermal relic annihilating dark matter with mass $m \le 100$ GeV for some popular annihilation channels. By using the new observed radio data of the Andromeda galaxy, we rule out the existence of $\sim 100-300$ GeV thermal relic annihilating dark matter for ten annihilation channels. The lower limits of annihilating dark matter mass are improved to larger than 330 GeV for the most conservative case, which is a few times larger than the current best constraints. Moreover, these limits strongly disfavor the benchmark model of weakly interacting massive particle (WIMP) produced through the thermal freeze-out mechanism.