Astronomy & Astrophysics Seminar: Searching for Nuclear Transients via Large Optical Sky Surveys

Zoom: https://us02web.zoom.us/j/84211520648?pwd=dllEbUhBU1VRUDZPL2lWRnhjWEdzZz09

Abstract:

Active Galactic Nuclei (AGN) and Tidal Disruption Events (TDEs) are two phenomena that can lead to a deeper understanding of the supermassive black holes (SMBHs) that reside at the centres of all massive galaxies. Past optical surveys, such as the SDSS and PTF, have opened the way to studying both these phenomena using large samples of data. Current (e.g. ZTF) and future (e.g LSST) surveys will provide long timespan, high cadence lightcurves for millions more galaxies than these earlier surveys, allowing us to study AGN variability (including extremest phenomena like Changing-Look AGN) and TDEs to an even greater level of detail. In this talk, I will focus on the possibilities and challenges of searching TDEs but also extreme/unusual AGN activity in large datasets provided by large optical surveys and what we can learn from large statistical studies on these events. I will discuss the methods we can use to make this search of nuclear transients efficient but also the tools that the astronomical community has developed for this task. I will highlight why photometric data can and should be used as a means to identify these events in the big data era but also the caveats for that. Finally, I discuss some first results from searching for nuclear transients in ZTF and Gaia data.

Seminar Organizer: Dr. Iair Arcavi