Overview
- University of Tokyo astronomer Tomonori Totani reports a diffuse gamma-ray excess around the Milky Way that maps the expected shape of a dark matter halo.
- The measured spectrum rises to a sharp peak near 20 GeV, implying WIMP-like particles roughly 500 times the mass of a proton and an annihilation rate consistent with standard models.
- The reported glow extends across the Galactic halo and is distinct from the long-debated Galactic Centre excess concentrated at the core.
- Experts caution that uncertain astrophysical backgrounds and modelling choices in Fermi data could mimic such a signal, urging independent reanalyses before any dark matter claim is accepted.
- Proposed tests include searching for the same 20 GeV signature in dark-matter–dominated dwarf galaxies, deeper Fermi cross-checks, observations with the Cherenkov Telescope Array Observatory, and comparisons with underground direct-detection experiments.