2019/12/16 by Andrey Katz, Joachim Kopp, Sergey Sibiryakov +1
Physics and Astronomy · #Astronomy #Astrophysics #Cosmology and Gravitation Theories #Gamma-ray bursts and supernovae #Physics #Pulsars and Gravitational Waves Research #Spectral line #astro-ph.CO #astro-ph.HE #hep-ph
paper · pdf · doi:10.1093/mnras/staa1497
34 pages, 11 figures. code available at https://github.com/andrey-katz/FRB_lensing
arxiv created 2019/12/16 · openalex publication_date 2020/06/10 · arxiv updated 2020/06/17 · openalex created_date 2025/10/10 · openalex updated_date 2026/08/05
ABSTRACT We explore a novel search strategy for dark matter in the form of massive compact halo objects (MACHOs) such as primordial black holes or dense mini-haloes in the mass range from 10-4 M\odot to 0.1 M\odot . These objects can gravitationally lens the signal of fast radio bursts (FRBs), producing a characteristic interference pattern in the frequency spectrum, similar to the previously studied femtolensing signal in gamma-ray burst spectra. Unlike traditional searches using microlensing, FRB lensing will probe the abundance of MACHOs at cosmological distance scales (∼Gpc) rather than just their distribution in the neighbourhood of the Milky Way. The method is thus particularly relevant for dark mini-haloes, which may be inaccessible to microlensing due to their finite spatial extent or tidal disruption in galaxies. We find that the main complication in FRB lensing will be interstellar scintillation in the FRB’s host galaxy and in the Milky Way. Scintillation is difficult to quantify because it heavily depends on turbulence in the interstellar medium, which is poorly understood. We show that, nevertheless, for realistic scintillation parameters, FRB lensing can set competitive limits on compact dark matter object, and we back our findings with explicit simulations.