Fast Radio Burst/Gamma-Ray Burst Cosmography [CEA]

Recently, both theoretical arguments and observational evidence suggested that a small fraction of fast radio bursts (FRBs) could be associated with gamma-ray bursts (GRBs). If such FRB/GRB association systems are commonly detected in the future, the combination of dispersion measure (DM) derived from FRBs and redshifts derived from GRBs makes these systems a plausible tool to conduct cosmography. We quantify uncertainties in deriving redshift-dependent DM_{IGM}} as a function of z, and test how well dark energy models can be constrained with Monte Carlo simulations. We show that with potentially several 10s of FRB/GRB systems detected in a decade or so, one can reach reasonable constraints on wCDM models. When combined with SN Ia data, unprecedented constraints on dark energy equation of state can be achieved, thanks to the prospects of detecting FRB/GRB systems at relatively high redshifts. The ratio between the mean value < DM_{IGM} (z)> and luminosity distance (D_{L} (z)) is insensitive to dark energy models. This gives the prospects of applying SN Ia data to calibrate < DM_{IGM} (z)> using a relatively small sample of FRB/GRB systems, allowing a reliable constraint on the baryon inhomogeneity distribution as a function of redshift.

Read this paper on arXiv…

H. Gao, Z. Li and B. Zhang
Wed, 12 Feb 14