Event Description
Posted: August 19, 2004 3:46 pm |
Over the past five years, the Chandra X-ray Observatory has repeatedly observed Sgr A, the compact radio source and supermassive black hole at the dynamical center of the Milky Way. The deep exposure coupled with Chandra's 0.5 arcsecond resolution have produced the most sensitive X-ray image of our Galactic center, allowing us to study the central black hole and its environment in unprecedented detail. Sgr A is extremely faint in X-rays, radiating about 11 orders of
magnitude below the Eddington limit. The properties of this emission will be discussed, along with the emission from surrounding stars and structures in the central parsecs of the Galaxy. In October 2000,Chandra discovered a rapid, large-amplitude X-ray flare from Sgr A. This extreme activity was totally unexpected. Chandra and XMM-Newton have since shown that Sgr A flares in X-rays on a daily basis. NIR flares have been discovered within the last year at about three times the rate of the X-ray flares, raising the question of whether the
X-ray and NIR flares are produced by the same or different processes. I will present results from the first simultaneous detection of an X-ray and NIR flare from Sgr A*. At least in this case, the X-rays and NIR photons appear to arise from the same electron population.
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