Astrophysics Colloquium

Abstract: I will discuss some of the exciting transient science enabled by new and upcoming astrophysical time domain surveys. I’ll start by outlining the physics we can derive from the spectra of kilonovae, explosions resulting from the merger of two neutron stars, in the context of the first (and only) gravitational wave multi-messenger event, GW170817. I’ll focus on a new tool, “Spectroscopic r-Process Abundance Retrieval for Kilonovae” (SPARK), which offers an engine for performing Bayesian inference on kilonova spectra to (1) retrieve elemental abundance patterns, and (2) identify individual absorption features in early-time, optically-thick spectra. I’ll also discuss the upcoming LIGO-Virgo-KAGRA O4 campaign in which some 2-10 NS-NS and NS-BH mergers are anticipated (median localization ~100 sq.deg). If EM counterparts can be identified, these new multi-messenger discoveries will push beyond the single detection of a kilonova to help us identify a population of well characterized BH and NS encounters. I’ll wrap up with a wider discussion of explosive transients and prospects for studying them with existing and upcoming facilities, including Chandra, CFHT, JWST, the current (and next generation) Event Horizon Telescope, LISA, and proposed X-ray and UV facilities.