Transient Radio Signatures from Neutron Star Encounters with QCD Axion Miniclusters
Abstract
The QCD axion is expected to form dense structures known as axion miniclusters if the Peccei-Quinn symmetry is broken after inflation. Miniclusters that have survived until today will interact with neutron stars (NSs) in the Milky Way to produce transient radio signals from axion-photon conversion in the NS magnetosphere. We quantify the properties of these encounters and find that they occur frequently [O (1 - 100 )day-1 ], last between a day and a few months, are spatially clustered toward the Galactic Center, and can reach observable fluxes. These radio transients are within reach of current generation telescopes and therefore offer a promising pathway to discovering QCD axion dark matter.
- Publication:
-
Physical Review Letters
- Pub Date:
- September 2021
- DOI:
- 10.1103/PhysRevLett.127.131103
- arXiv:
- arXiv:2011.05378
- Bibcode:
- 2021PhRvL.127m1103E
- Keywords:
-
- High Energy Physics - Phenomenology;
- Astrophysics - Cosmology and Nongalactic Astrophysics;
- Astrophysics - Astrophysics of Galaxies
- E-Print:
- 11 pages, 5 figures. Code is available online at https://github.com/bradkav/axion-miniclusters/ (archived at https://doi.org/10.5281/zenodo.4006128 ). Joint submission with "Stellar Disruption of Axion Miniclusters in the Milky Way" in astro-ph (arXiv:2011.05377). Updated to match published version