Events Daily

Tuesday, October 19, 2021

The Landscape of Relativistic Stellar Explosions
Anna Ho, Berkeley
Event Type: Astro Seminar
Time: 2:00 PM - 3:30 PM
Location: 726 Broadway, 940, CCPP Seminar
Abstract: Decades of observations of long-duration gamma-ray bursts GRBs, attributed to relativistic jets launched in the collapse of massive stars, have yielded important insights on massive-star evolution, compact-object formation, and the physics of relativistic outflows. A major outstanding mystery is whether GRBs detected at only 0.1% of the supernova rate simply represent the tip of the iceberg in a vast landscape of phenomena. To answer this question, with the Zwicky Transient Facility ZTF we are conducting a systematic exploration of the rest of the iceberg via searches for fast hour to day optical transients. In the past few years our searches yielded several orphan afterglows afterglows without detected GRBs at cosmological distances, supernovae with luminous X-ray and radio emission, and mildly relativistic explosions in dense circumstellar matter. Understanding the origin of these events and their relation to GRBs will require coordinated observations between high-cadence optical surveys, wide-field X-ray monitors, and millimeter and radio observatories. This will be possible in the next few years with the launch of the Space-based multi-band astronomical Variable Objects Monitor SVOM, the enhanced cadence of ZTF Phase II, and sensitive millimeter-band facilities like the Atacama Large Millimeter Array ALMA.

Link to the Event Video