Constraints on the distribution and energetics of fast radio bursts using cosmological hydrodynamic simulations

Understand

We present constraints on the origins of fast radio bursts (FRBs) using large cosmological simulations.

• We calculate contributions to FRB dispersion measures (DMs) from the Milky Way, from the local Universe, from cosmological large-scale structure, and from potential FRB host galaxies, and then compare these simulations to the DMs of observed FRBs.
• We find that the Milky Way contribution has previously been underestimated by a factor of ~2, and that the foreground-subtracted DMs are consistent with a cosmological origin, corresponding to a source population observable to a maximum redshift z~0.6-0.9.
• We consider models for the spatial distribution of FRBs in which they are randomly distributed in the Universe, track the star-formation rate of their host galaxies, track total stellar mass, or require a central supermassive black hole.