Astronomy & Astrophysics Seminar: Dynamics and Energetic Transients in Galactic Nuclei

Zoom: https://tau-ac-il.zoom.us/j/81850414917?pwd=hOoiUteqh6KKoO6pzUfM8jmYjZJWZP.1

Abstract:

Centers of galaxies host a variety of dynamical processes, owing to the high density of stars and the presence of a central Supermassive Black Hole (SMBH). Orbital relaxation brings stellar objects into close encounters with the SMBH, driving a plethora of energetic phenomena. These include tidal disruption events, stellar collisions, the formation of X-ray binaries, compact object mergers detectable by LIGO, and gravitational wave (GW) inspirals of stellar objects towards the SMBH. In this talk, I will review some of these processes and their observable signatures, with an emphasis on newly discovered classes of repeating flares associated with SMBHs. I will discuss theoretical models, key open questions, and how these phenomena inform our understanding of accretion physics, SMBH growth and evolution, and the connection to their host galaxies. A powerful array of current and upcoming time-domain surveys and instruments will uncover thousands of high-energy sources in galactic nuclei in the coming years. I will highlight how theoretical interpretation of these discoveries can address fundamental questions in astrophysics, and conclude with broader implications for multi-messenger observations in the era of space-based GW detectors such as LISA.

Seminar Organizer: Dr. Jonathan Stern