Joint Astrophysics Colloquium

The Transient Revolution in Astrophysics

Eliot Quataert

UC Berkeley

The advent of large astronomical surveys based on rapid advances in detector technology and data storage is generating an unprecedented amount of data on time-variable astronomical objects, up to 100 Terabytes per night in the coming decade. In addition to providing new insights into a wide variety of known phenomena (e.g., variable stars, supernovae, and black holes), historical analogues suggest that these surveys are likely to discover entirely new classes of astronomical objects. I will illustrate the discovery potential of the current generation of astrophysical transient surveys by focusing on two concrete examples of “known unknowns”. The first is a “mini-supernova” produced by radioactive Nickel created during the merger of two neutron stars or a neutron star and a black hole; a similar transient can be produced during the collapse of a white dwarf to a neutron star. These events are particularly interesting since they are the likely progenitors of some gamma-ray bursts and are also the primary target for km-scale gravitational wave observatories such as Advanced LIGO. The second “known unknown” I will highlight is a ~ month-long electromagnetic flare produced by the tidal disruption of a star that passes close to the event horizon of a massive black hole at the center of a galaxy. The study and characterization of mini-supernovae and tidal disruption events in the coming years will open up a new window onto the physics and astrophysics of compact objects in the universe.