Dusty features and accretion onto the Galactic Center supermassive black hole

The proximity of the Galactic Center makes it unique for studying the kinds of interactions that might be taking place between the interstellar medium, the stars and the supermassive black holes in galactic nuclei. We used 13 years of data collected by OSIRIS, the NIR IFU at Keck Observatory to study the dynamics and temporal variability of gas. We highlighted several compact emission sources in Brγ emission line which are orbiting closely around the central supermassive black hole. These objects appear to have many of the same characteristics as the tidally-interacting object, G2. The discovery and characterization of these additional objects demonstrate the existence of a population of these "G-objects". The G objects are possibly the residuals of binaries merged under the influence of the black hole. These objects potentially offer a mechanism to episodically transport material onto the black hole and enhance its activity. The accretion rate of cooler gas very near the black hole is not strongly constrained. With our large OSIRIS data-set we produced the highest signal-to-noise near-infrared spectrum of the immediate vicinity of the central black hole and test models of the accretion flow.

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