Detecting Axion Stars with Radio Telescopes

Abstract

When axion stars fly through an astrophysical magnetic background, the axion-to-photon conversion may generate a large electromagnetic radiation power. After including the interference effects of the spacially-extended axion-star source and the macroscopic medium effects, we estimate the radiation power when an axion star meets a neutron star. For a dense axion star with $10^{-13}{M}_{\odot }$, the radiated power is at the order of $10^{11}\,\mbox{W}\times(100\,μ\mbox{eV}/m_a)^4\,(B/10^{10}\,\mbox{Gauss})^2$ with $m_a$ as the axion particle mass and $B$ the strength of the neutron star magnetic field. For axion stars occupy a large fraction of dark matter energy density, this encounter event with a transient $\mathcal{O}(0.1\,\mbox{s})$ radio signal may happen in our galaxy with the averaged source distance of one kiloparsec. The predicted spectral flux density is at the order of $\mu$Jy for a neutron star with $B\sim 10^{13}$ Gauss. The existing Arecibo, GBT, JVLA and FAST and the ongoing SKA radio telescopes have excellent discovery potential of dense axion stars.

16 pages, 2 figures

References in corpus (19)

• A bright millisecond radio burst of extragalactic origin
• The Five-Hundred-Meter Aperture Spherical Radio Telescope (FAST) Project
• Experimental Searches for the Axion and Axion-like Particles
• Fast Radio Burst Discovered in the Arecibo Pulsar ALFA Survey
• Bose-Einstein Condensation of Dark Matter Axions
• Transient pulsed radio emission from a magnetar
• Magnetic White Dwarfs
• First results from a microwave cavity axion search at 24 micro-eV
• New white dwarf and subdwarf stars in the Sloan Digital Sky Survey Data Release 12
• Dense Axion Stars
• Fast Radio Bursts---A Brief Review: Some Questions, Fewer Answers
• Searching for the QCD Axion with Gravitational Microlensing
• Emission of Photons and Relativistic Axions from Axion Stars
• Axion star collisions with Neutron stars and Fast Radio Bursts
• Hydrogen Axion Star: Metallic Hydrogen Bound to a QCD Axion BEC
• Astrophysical Haloscopes
• A Radio Astronomy Search for Cold Dark Matter Axions
• FRBs and dark matter axions
• Radiation and energy release in a background field of axion-like dark matter

Cited by in corpus (28)

• Wave Dark Matter
• Early-Universe Simulations of the Cosmological Axion
• Early seeds of axion miniclusters
• Small-scale structure of fuzzy and axion-like dark matter
• Boson Stars and Oscillatons: A Review
• The radio telescope search for the resonant conversion of cold dark matter axions from the magnetized astrophysical sources
• Phase transitions between dilute and dense axion stars
• Simulations of Axion Minihalos
• Axion Cosmology with Early Matter Domination
• Fast radio bursts from axion stars moving through pulsar magnetospheres
• Neutron star -- axion star collisions in the light of multi-messenger astronomy
• Dipole Radiation and Beyond from Axion Stars in Electromagnetic Fields
• Cooling binary neutron star remnants via nucleon-nucleon-axion bremsstrahlung
• Transient Radio Lines from Axion Miniclusters and Axion Stars
• Axion configurations around pulsars
• Resonant Conversion of Dark Matter Oscillons in Pulsar Magnetospheres
• Diluted Axion Star Collisions with Neutron Stars
• Quantum tunneling rate of dilute axion stars close to the maximum mass
• Opening up a window on the postinflationary QCD axion
• Optical Lensing by Axion Stars: Observational Prospects with Radio Astrometry
• Astrophysical Searches and Constraints on Ultralight Bosonic Dark Matter
• Acoustic modes of pulsating axion stars: Non-radial oscillations
• Magnetic fields in inhomogeneous axion stars
• Neutrino Energy Loss Rates in 3-3-1 Models
• Superdense beaming of axion dark matter in the vicinity of the light cylinder of pulsars
• Radiation from Axion star-Neutron star binaries with a tilted rotation axis in the presence of plasma
• Resonant Axion Radiation Conversion in Solar Spicules
• Radiation Burst by Axion Star Collision with Star in the Andromeda Galaxy