3rd International Conference on Astronomy and Space Science
The Education University of Hong Kong, China
Title: Ruling out~100-300 GeV thermal relic annihilating dark matter by radio observation of the Andromeda galaxy
Biography: Chan Man Ho
In the past few years, some studies claimed that annihilating dark matter with mass~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<100 GeV for some popular annihilation channels. In this presentation, we present our latest observed radio data of the Andromeda galaxy. 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.