Testing strong gravity using X-ray reflection spectroscopy

Dr. Cosimo Bambi (host Krawczynski), Department of Physics, Fudan University
April 17, 2018 at 12:00 pm
241 Compton
Event Description 

Einstein's theory of general relativity was proposed over 100 years ago and has successfully passed a large number of observational tests in the weak field regime. However, the strong field regime is largely unexplored, and there are many modified and alternative theories that have the same predictions as Einstein's gravity for weak fields and present deviations when gravity becomes strong. X-ray reflection spectroscopy is becoming a powerful tool for testing the strong gravity region around astrophysical black holes with electromagnetic radiation. In my talk, I will present the new model RELXILL_NK, which is the first X-ray reflection model for testing the Kerr metric, as well as some preliminary constraints obtained with XMM-Newton, NuSTAR, and Swift data.