Fast Transients: A Window on the Final Stages of Stellar Evolution and Compact Objects Formation

Tor Vergata Astrophysics Seminars - Anna Ho (University of California, Berkeley) - Fast Transients: A (Fleeting) Window on the Final Stages of Stellar Evolution and the Formation of Compact Objects - 30/03/2022 Abstract In the last few years, the discovery of cosmic explosions has become routine: every night, robotic optical telescopes mosaic the sky with a time resolution of minutes to days and identify 10^5 candidate new transients. In my talk, I will illustrate how to sift through the transient deluge with well-defined criteria and conduct prompt follow-up observations using telescopes spanning the electromagnetic spectrum, such as Keck, ALMA, and the VLA. I will describe how this approach has enabled us to answer decades-old questions in the field of gamma-ray bursts and discover unexpected types of cosmic explosions that are prime targets for millimeter-band observatories such as CMB-S4. I will summarize the implications for the next generation of time-domain surveys spanning the electromagnetic spectrum: how to most effectively use those observations to connect the final stages of stellar evolution and the formation (and afterlives) of compact objects to the observed characteristics of transients and remnants, and ultimately rewrite the story of massive-star evolution.