Constrain cosmological parameters from FRB-GW association events without redshifts

Fast radio bursts (FRBs) are among the most mysterious astronomical transients. Due to their short durations and cosmological distances, their dispersion measure (DM) – redshift (z) relation is useful for constraining cosmological parameters and detecting the baryons in the Universe. However, localizing FRBs and obtaining their redshifts is not an easy task. Some previous research suggests that fast radio bursts may be the electromagnetic counterpart of gravitational waves. If there are FRB-GW association events, one can use the DM - luminosity distance relation to constrain the cosmological parameters. In this paper, we use Bayesian analysis to study this possibility.