Resolving the photon ring

QUEST Center event
No
Speaker
Shahar Hadar, Oranim (Haifa University)
Date
21/06/2023 - 15:30 - 14:00Add to Calendar 2023-06-21 14:00:00 2023-06-21 15:30:00 Resolving the photon ring In the past few years, the Event Horizon Telescope has released the first close-up interferometric images of two supermassive black holes, M87* and SgrA*. It is believed that within these images is embedded a fine, yet-unresolved brightness enhancement called the photon ring. The ring is a universal consequence of strong lensing by the black hole and thereby conveys information on its spacetime geometry, potentially providing a new independent avenue for tests of general relativity in the strong-field regime. In the talk I will review the theory of the photon ring and its corresponding spacetime region, the photon shell, which governs the universal lensing structure. I will then describe some current efforts and future prospects for resolving the ring, which include both the construction of more powerful instruments and the development of novel analysis methods. Physics Building 202 Seminar Room 303 Department of Physics physics.dept@mail.biu.ac.il Asia/Jerusalem public
Place
Physics Building 202 Seminar Room 303
Abstract

In the past few years, the Event Horizon Telescope has released the first close-up interferometric images of two supermassive black holes, M87* and SgrA*. It is believed that within these images is embedded a fine, yet-unresolved brightness enhancement called the photon ring. The ring is a universal consequence of strong lensing by the black hole and thereby conveys information on its spacetime geometry, potentially providing a new independent avenue for tests of general relativity in the strong-field regime. In the talk I will review the theory of the photon ring and its corresponding spacetime region, the photon shell, which governs the universal lensing structure. I will then describe some current efforts and future prospects for resolving the ring, which include both the construction of more powerful instruments and the development of novel analysis methods.

Last Updated Date : 19/03/2023