Measurements of black hole spin with X-ray spectroscopy

     
 

 

The past few years have seen remarkable progress in the use of X-ray spectroscopy as a probe of the immediate vicinity of accreting black holes. In particular, several techniques have been developed to measure the spin of black holes, an important quantity for our understanding of both the formation/evolution of the black hole as well as the physics of accretion. I will discuss both the theoretical basis and the observational status of black hole spin measurements. My focus will be on measurements that result from studies of the X-ray reflection spectrum from the black hole accretion disk; this technique has been applied successfully to both stellar-mass and supermassive black holes. I will finish by discussing the future of black hole spin studies and, in particular, the ability of the International X-ray Observatory to determine the spin distribution function of the local supermassive black hole population.

Chris Reynolds