| Speaker: | Sunil Simha (NorthWestern/UChicago) |
|---|---|
| Title: | FRBs as foreground probes: Recent results from the CHIME collaboration and ongoing work with FLIMFLAM |
| Date (JST): | Thu, Mar 26, 2026, 13:30 - 15:00 |
| Place: | Seminar Room A |
| Abstract: |
The field of Fast Radio Bursts (FRBs) is experiencing a rapid growth in FRB detections spearheaded by the CHIME/FRB collaboration. The CHIME Outrigger telescopes have come into full operation since early 2025 and have enabled sub-arcsecond-scale VLBI localizations of tens of published FRBs to date. Subsequently, our optical follow-up led by the F^4 team is steadily associating the bursts with their hosts and obtaining spectroscopic redshifts for these bursts. Armed with the FRB dispersion measures (DM) and their host redshifts, we are now able to constrain the gas distribution along the FRB sightlines. In my talk, I will provide an overview of our early results, including: (1) constraints on galactic feedback models prevalent in FRB hosts, (2) baryon retention fractions in group and cluster halos, (3) host galaxy ISM constraints from an extremely bright nearby (~40 Mpc) burst, and (4) a statistical hint of halo gas around M31. I will also highlight some of the ongoing work on the FLIMFLAM project, an effort to constrain gas in halos and the IGM via spectroscopic maps of foreground galaxies. |
