Sgr A* and its environment: insights from X-ray observations

Almost every massive galaxy has at least one super-massive black hole (SMBH) at its center. Most (>90%) of those SMBHs are quiet. Understanding the accretion of low-luminosity SMBHs represents a very important and fundamental problem in astronomy. As an extreme representative of low-luminosity SMBHs, Sgr A* in our own Galaxy provides us with a unique opportunity to study the accretion process and its interaction with the environment in great detail. I will review a set of very recent studies, based primarily on extensive Chandra X-ray observations, including a systematic detection and statistical analysis of X-ray flares, as well as on 2-D and 3-D hydrodynamic simulations suited to explore the accretion close to the SMBH or the detailed interaction of stellar winds from individual massive stars orbiting around it. I will show how these simulations are compared with X-ray observations, what insights we have learned from this comparison, and how future studies can further advance our understanding of the phenomenon. These studies will help to understand a class of low-luminosity SMBHs and their interplay with circum-nuclear medium.

12/05/2016 - 12:30
Dr. Daniel Wang
University of Massachusetts