Princeton University Gravity Initiative Seminar
Where is the Second Multi-Messenger Compact Object Merger? Insight from Observations of GRBs, Kilonovae and Afterglows
Abstract: With only one joint gravitational wave (GW)-electromagnetic (EM) detection to date, observations of the EM counterparts to neutron star mergers are a key path to probing the physics of these unique systems and predicting the behavior of future EM counterparts to GW events. In this talk, I will discuss the major takeaways revealed by decades of observations of gamma-ray bursts (GRBs), heavy element creating-kilonovae and multi-wavelength afterglows. First, I will present insights from rapid follow-up of short GRBs, which reveal the diversity of kilonovae uniformly observed at a pole-on angle and a span in jet properties. Against this backdrop, I will show our surprising discovery of a kilonova following a long GRB (duration ~ 50s) at 350 Mpc, which illuminates a new avenue to detect future mergers. Finally, I will show that recent increases in afterglow coverage is improving our understanding of the distribution of NS merger jet properties. I will discuss how we are leveraging these archival observations to improve our predictions for joint GW-EM detections in the era of Cosmic Explorer and Einstein Telescope as well as next-generation EM observatories.