2023/08/18 by Masoud Rafiei-Ravandi, Kendrick M. Smith, Rafiei-Ravandi, Masoud +36 · 1 citation
Physics and Astronomy · #Astronomy and Astrophysical Research #Astrophysics and Cosmic Phenomena #Astrophysics of Galaxies (astro-ph.GA) #Cosmology and Nongalactic Astrophysics (astro-ph.CO) #FOS: Physical sciences #Galaxies: Formation, Evolution, Phenomena #High Energy Astrophysical Phenomena (astro-ph.HE)
paper · pdf · doi:10.48550/arxiv.2308.09608
openalex publication_date 2023/08/18 · openalex created_date 2023/08/22 · openalex updated_date 2026/07/28
We present results from angular cross-correlations between select samples of CHIME/FRB repeaters and galaxies in three photometric galaxy surveys, which have shown correlations with the first CHIME/FRB catalog containing repeating and nonrepeating sources: WISE×SCOS, DESI-BGS, and DESI-LRG. We find a statistically significant correlation (p-value <0.001, after accounting for look-elsewhere factors) between a sample of repeaters with extragalactic dispersion measure DM >395 pc cm-3 and WISE×SCOS galaxies with redshift z>0.275. We demonstrate that the correlation arises surprisingly because of a statistical association between FRB 20200320A (extragalactic DM ≈550 pc cm-3) and a galaxy group in the same dark matter halo at redshift z≈0.32. We estimate that the host halo, along with an intervening halo at redshift z≈0.12, accounts for at least ∼30% of the extragalactic DM. Our results strongly motivate incorporating galaxy group and cluster catalogs into direct host association pipelines for FRBs with \lesssim1' localization precision, effectively utilizing the two-point information to constrain FRB properties such as their redshift and DM distributions. In addition, we find marginal evidence for a negative correlation at 99.4% CL between a sample of repeating FRBs with baseband data (median extragalactic DM =354 pc cm-3) and DESI-LRG galaxies with redshift 0.3≤ z<0.45, suggesting that the repeaters might be more prone than apparent nonrepeaters to propagation effects in FRB-galaxy correlations due to intervening free electrons over angular scales ∼0. ^∘5.