Cosmological Parameter Estimate from Persistent Radio Sources of Fast Radio Bursts

Abstract We introduce a novel method to constrain the Hubble constant ( H 0 ) by combining fast radio bursts (FRBs) and their persistent radio sources (PRSs) through the observationally validated Yang relation, L ν ∝ ∣RM∣, which links PRS luminosity to the rotation measure of the associated FRB. Using a mock sample of PRSs, we demonstrate that the Yang relation can help to unravel the degeneracies among H 0 , baryon density parameter Ω b , and baryon fraction in the intergalactic medium f IGM in the traditional approach of using dispersion measure only to perform cosmological analyses. Our method employs a two-stage Markov Chain Monte Carlo analysis to constrain H 0 . Using the available data of six observed PRS systems, we obtain a preliminary constraint of H 0 = 75 ± 30 km s −1 Mpc −1 . We briefly discuss possible refinements of the method by reducing residual degeneracies and systematic uncertainties using future data and physical modeling. Our results indicate that the Yang relation can potentially become a new probe for performing FRB cosmology.