We use observations of gas-rich dwarf galaxies to derive constraints on dark matter scattering with ordinary matter. We require that heating/cooling due to dark matter (DM) interacting with gas in the Leo T dwarf galaxy not exceed the ultralow radiative cooling rate of the gas. This enables us to set (i) stronger bounds than all the previous literature on ultralight hidden photon DM for nearly all of the mass range 10-23≲mDM≲10-10 eV , (ii) limits on sub-GeV millicharged DM which add to the constraints on the recent EDGES 21 cm absorption anomaly, and (iii) constraints on DM-baryon interactions directly at low relative velocities vrel∼17 km /s . Our study opens a new direction in using observations of gas-rich dwarf galaxies from previous, current, and upcoming optical and 21 cm surveys to probe physics beyond the standard model.
Physical Review D
- Pub Date:
- June 2021
- High Energy Physics - Phenomenology;
- Astrophysics - Astrophysics of Galaxies
- 5+10 pages, 4+6 figures. Version appearing in PRD. Title and abstract revised to reflect the primary message of the paper. Minor changes to figures, conclusions unchanged. The code associated with this paper is available at https://github.com/JayWadekar/Gas_rich_dwarfs