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Starburst Galactic Nuclei as Light Dark Matter Laboratories
Antonio Ambrosone1,2, Marco Chianese1,2, Damiano F G Fiorillo3
1Dipartimento di Fisica "Ettore Pancini," Università degli studi di Napoli "Federico II," Complesso Univ. Monte S. Angelo, I-80126 Napoli, Italy.
Physical Review Letters
|September 29, 2023
Summary
Starburst galaxies emit gamma rays, acting as cosmic-ray reservoirs. Interactions with dark matter could distort cosmic rays, but current data show no such effects, yielding new limits on dark matter properties.
Area of Science:
- Astrophysics
- Particle Physics
Background:
- Starburst galaxies are significant sources of high-energy gamma rays.
- Their turbulent magnetic fields trap high-energy protons for extended periods, forming cosmic-ray reservoirs.
Purpose of the Study:
- Investigate the impact of dark matter interactions on cosmic-ray transport within starburst galaxies.
- Establish constraints on the proton-dark matter cross-section using gamma-ray observations.
Main Methods:
- Analyze the cosmic-ray spectrum for distortions caused by scattering with sub-GeV dark matter.
- Utilize existing gamma-ray data from starburst galaxies to search for spectral anomalies.
- Compare observational data with theoretical predictions of cosmic-ray propagation.
Main Results:
- No evidence of spectral distortion from cosmic-ray scattering with dark matter was found in current gamma-ray data.
- Stringent new bounds were placed on the proton-dark matter cross-section.
- These results are complementary to existing constraints from other experiments.
Conclusions:
- Current gamma-ray observations of starburst galaxies provide strong constraints on dark matter properties.
- Future observations with the Cherenkov Telescope Array in the 0.1-10 TeV range could improve these limits by up to two orders of magnitude.
- Starburst galaxies offer a unique astrophysical laboratory for probing dark matter interactions.
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