Constraining the Cosmic Baryon Distribution with Fast Radio Burst Foreground Mapping

The dispersion measures (DM) of fast radio bursts (FRBs) encode the integrated electron density along line-of-sight, which is typically dominated by intergalactic medium (IGM) contribution in case extragalactic FRBs. In this paper, we show that incorporating wide-field spectroscopic galaxy survey data foreground localized FRBs can significantly improve constraints on partition diffuse cosmic baryons. Using mock DMs and realistic lightcone catalogs derived from Millennium simulation, define surveys be carried out with 4m 8m-class wide field facilities. On these simulated surveys, carry Bayesian reconstructions order to estimate matter field. comparison `true' field, help reduce uncertainties structures $\sim 2-3\times$ compared variance. We calculate Fisher matrix forecast $N=30\: (96)$ should able constrain baryon fraction 10\%\: (\sim 5\%) $, parameters governing size circumgalactic halos within 20-25\%\: 8-12\%)$. From analysis, increases sensitivity toward our interest 25\times$. briefly introduce FLIMFLAM, an ongoing redshift aims obtain 30$ FRB fields.