Periodic Reporting for period 2 - Fireworks (Celestial fireworks: revealing the physics of the time-variable sky)
Reporting period: 2019-03-01 to 2020-08-31
Understanding transient astrophysical phenomena is a key to understanding fundamental problems in astrophysics and physics in general, and move our understanding of the physical universe surrounding us forward.
* measured for the first time the fraction of all massive stars that explode within clouds of surrounding matter, and showed this is ubiquitous (60% of cases), indicating that massive stars undergo a period of rapid
mass loss prior to their terminal explosion; this is unexplained by standard models of stellar evolution, and require a new thinking about massive star evolution, structure, and explosion as supernovae.
* We have found the first example of an exploding star within a Wolf-Rayet wind nebula.
* We have contributed to the discovery of the first gravitational-wave counterpart, GW170817.