Our central Galactic supermassive black hole, Sgr A*, spends most of its time in a very non-AGN-like, extremely low-luminosity (~10^{-9}L_Edd), thermal quiescent state. More typical activity is observed approximately daily, however, in the form of short-lived, nonthermal X-ray flares. These flares provide important clues about the origins of galactic nuclear activity, including jet formation, when starving supermassive black holes are fed. Furthermore, by considering Sgr A* in the context of other weakly accreting black holes of all scales, we can better constrain its own internal physical processes. I will present several recent results from coordinated multi-wavelength studies of weakly accreting black hole binaries, as well as some low-luminosity AGN, with a particular focus on the possible role of outflows. These results include the interpretation of trends demonstrating that lower frequency (e.g., radio and infrared) observations, in combination with those in X-rays, are a powerful tool for studying the regions near the compact object. After discussing these general trends, I will explore Sgr A*'s relationship to other starving black holes as a class. By comparing accretion around drastically different sized black holes, we can test if unified schemes for inflow/outflow relationships are truly self-similar.
Tuesday, May 24th
Seminar is to be held at 4:00 PM in the conference room
on the second floor of Dearborn Observatory
Refreshments will be served at 3:30
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