Sunil Simha

Sunil Simha’s research uses Fast Radio Bursts (FRBs) as probes of matter in the universe. FRBs are flashes of radio light that frequently occur all over the sky daily. Using sensitive radio telescopes, astronomers can detect and pinpoint their locations to distant galaxies from which they originate. Due to their unique millisecond-duration flash, they offer an exciting new window to matter in the universe. Most of the matter, a.k.a. baryons, in the universe is present in a highly diffuse and ionized state, a plasma, which makes them difficult to detect. However, FRBs are dispersed when propagating through this plasma, much like sunlight is dispersed by raindrops to make a rainbow. Measuring this dispersion accurately tells us exactly how much matter the FRB has traveled through, thus directly detecting them. As a NU-UChicago Brinson Postdoctoral Fellow in Astrophysics, Simha’s research combines the information obtained through FRBs with 3D optical maps of the foreground universe to place novel constraints on plasma distribution around and between galaxies. This technique complements other probes of matter in the universe to give us a much more complete picture of the cycle of baryons between galaxies and their environments.