Starburst Nuclei as Light Dark Matter Laboratories
Abstract
Starburst galaxies are well-motivated astrophysical emitters of high-energy gamma-rays. They are well-known cosmic-ray "reservoirs", thanks to their large magnetic fields which confine high-energy protons for years. Over such long times, cosmic-ray transport can be significantly affected by scatterings with sub-GeV dark matter. Here we point out that this scattering distorts the cosmic-ray spectrum, and the distortion can be indirectly observed by measuring the gamma-rays produced by cosmic-rays via hadronic collisions. Present gamma-ray data show no sign of such a distortion, leading to stringent bounds on the cross section between protons and dark matter. These are highly complementary with current bounds and have large room for improvement with the future gamma-ray measurements in the 0.1-10 TeV range from the Cherenkov Telescope Array, which can strengthen the limits by as much as two orders of magnitude.
Cite
@article{arxiv.2210.05685,
title = {Starburst Nuclei as Light Dark Matter Laboratories},
author = {Antonio Ambrosone and Marco Chianese and Damiano F. G. Fiorillo and Antonio Marinelli and Gennaro Miele},
journal= {arXiv preprint arXiv:2210.05685},
year = {2023}
}
Comments
17 pages, 7 figures. v2: version published in Physical Review Letters