Transient Radio Lines from Axion Miniclusters and Axion Stars
arXiv:2212.08079 · doi:10.1103/PhysRevD.107.063013
Abstract
Gravitationally bound clumps of dark matter axions in the form of 'miniclusters' or even denser 'axion stars' can generate strong radio signals through axion-photon conversion when encountering highly magnetised neutron star magnetospheres. We systematically study encounters of axion clumps with neutron stars and characterise the axion infall, conversion and the subsequent propagation of the photons. We show that the high density and low escape velocity of the axion clumps lead to strong, narrow, and temporally characteristic transient radio lines with an expected duration varying from seconds to months. Our work comprises the first end-to-end modeling pipeline capable of characterizing the radio signal generated during these transient encounters, quantifying the typical brightness, anisotropy, spectral width, and temporal evolution of the radio flux. The methods developed here may prove essential in developing dedicated radio searches for transient radio lines arising from miniclusters and axion stars.
v2: Minor updates made to match published version. v1: 17 pages, 15 figures
References in corpus (25)
- Dilute and dense axion stars
- New insights into the formation and growth of boson stars in dark matter halos
- Green Bank and Effelsberg Radio Telescope Searches for Axion Dark Matter Conversion in Neutron Star Magnetospheres
- Astrophysical Effects of Scalar Dark Matter Miniclusters
- Radio Signal of Axion-Photon Conversion in Neutron Stars: A Ray Tracing Analysis
- First Simulations of Axion Minicluster Halos
- Dark matter axion detection in the radio/mm-waveband
- Axion Stars and Fast Radio Bursts
- Simulations of Axion Minihalos
- Axion astronomy with microwave cavity experiments
- Fast radio bursts from axion stars moving through pulsar magnetospheres
- Extraterrestrial Axion Search with the Breakthrough Listen Galactic Center Survey
- Miniclusters in the Axiverse
- Axion-photon conversion in strongly magnetised plasmas
- Transient Radio Signatures from Neutron Star Encounters with QCD Axion Miniclusters
- Phase-space distribution of unbound dark matter near the Sun
- Stellar Disruption of Axion Miniclusters in the Milky Way
- Towards Robust Constraints on Axion Dark Matter using PSR J1745-2900
- Structure of Axion Miniclusters
- Radio Line Properties of Axion Dark Matter Conversion in Neutron Stars
- Axion Production in Pulsar Magnetosphere Gaps
- Destruction of axion miniclusters in the Galaxy
- The Fourier formalism for relativistic axion-photon conversion, with astrophysical applications
- Radio signatures from encounters between Neutron Stars and QCD-Axion Minihalos around Primordial Black Holes
- Diluted Axion Star Collisions with Neutron Stars