Lunch talk on Mar. 23, 2020

The Physics of Superluminous Supernovae and Fast Optical Transients

Speaker:Liangduan Liu (BNU)

Venue:Video conference

Time:12:30 PM, Monday, March 23, 2020

Abstract:

The rapid development of several wide-field optical surveys is revolutionizing the field of time-domain transient astrophysics. The past ten years have opened up a new parameter space in time-domain astronomy with the discovery of transients defying our understanding of how stars explode. These extremes of the transient paradigm represent the brightest—called superluminous supernovae—and the fastest—known as fast optical transients—of the transient zoo. The physical origins of the extreme luminosity emitted by SLSNe are a hot topic in astrophysics research. In this talk, I will introduce multiple models for what conditions may produce an SLSN, including core collapse in particularly massive stars, millisecond magnetars, interaction with circumstellar material (CSM model). In addition, I will introduce a general theory of homologous explosions with constant opacity, paying special attention to the evolution of the photospheric radius. We find that regardless of the density distribution profile, the photosphere always increases early on and decreases at late times. This general behavior can be used to quickly diagnose whether the source originates from a supernova-like explosion.

Report PPT:SWIFAR_Liangduan Liu.pdf