Scattering Horizons for Extragalactic Fast Radio Bursts
Stella Ocker (Cornell University)
May 17 @ 12:00 PM - 1:00 PM
Extragalactic fast radio bursts (FRBs) flicker across the sky at millisecond timescales thousands of times per day. Despite their unknown origins, the chromatic propagation effects FRBs experience along their journeys to the observer can be used to probe the distribution and turbulence of ionized gas from the Milky Way to their host galaxies. FRB scattering, in particular, is sensitive to small-scale electron density fluctuations that are inaccessible to many other observational probes. In this talk I will discuss current constraints on scattering in the circumgalactic medium of the Milky Way and nearby galaxies, and the implied prospects for probing the circumgalactic medium with a large future sample of FRBs. In addition, I will discuss modeling of the cumulative scattering from the Milky Way to host galaxies for FRBs at redshifts > 1, which suggests that scattering may undermine the feasibility of using FRBs to probe galaxies and cosmology from near the peak of cosmic star formation to the epoch of reionization.
This talk will be in hybrid format. Please contact the department office for Zoom information.