Mysteries in the Transient Zoo

Astronomers recorded the explosive deaths of stars, called supernovae (SNe), almost two thousand years ago with SN 185. Many of the transient classes we study today were only identified in the last half century, including gamma-ray bursts, tidal disruption events, and fast blue optical transients. Some are newer still. Luminous fast blue optical transients (LFBOTs) only emerged in the last decade with AT2018cow. Recent wide-field, high-cadence optical surveys like the Zwicky Transient Facility have allowed us to find numerous transients in these classes every year. Using an arsenal of facilities spanning the electromagnetic spectrum, we can infer the physics behind them.

In this talk, I’ll introduce the landscape of transients and then focus on two problems I’m tackling. First, I’ll show how multi-wavelength observations of LFBOTs help us constrain fundamental properties of these mysterious events. These include their size, speed, energy of their outflow, and the density of their surrounding medium. Second, I’ll present preliminary work using radio observations of SNe to infer the mass-loss rate of their progenitor stars in the years before they exploded. This work brings us closer to learning what kinds of stars and what kinds of deaths lead to the transients we see!