Physics Colloquium: The Observable Properties of Supermassive Black Holes in Galactic Centers

Zoom: https://tau-ac-il.zoom.us/j/83476132371?pwd=NHZKL0N0ZHFQNFVka3BEaVJhVUI0Zz09

Abstract: 

Black holes (BHs) with masses in the range of millions to billions of solar masses are ubiquitous at the centers of galaxies and drive among the most luminous phenomenon in the universe: quasars. The means by which such supermassive BHs (SMBHs) form and evolve is unclear, and elucidating it requires good knowledge of their fundamental properties — mass and spin — as well as the reliable assessment of the rate by which they acquire mass from their immediate environs (e.g., during their “active” quasar phase). As these compact regions around SMBHs cannot be spatially resolved by current instruments on cosmologically relevant scales, surrogate techniques must be used. In this talk I will discuss how gravitational microlensing and self lensing, as well as light echos may be used to zoom in on the immediate environs of SMBHs in quasars and probe their fundamental astrophysical properties. Pending challenges will be outlined, as will the role of small telescopes and upcoming UV and X-ray space observatories in meeting them. 

Event Organizer: Dr. Hadas Soifer