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The supermassive black hole Sgr A* at the center of the Galaxy is surroundedby two misaligned disks of young, massive stars extending from ~0.04 to 0.4 pc.The stellar surface density increases as ~ r^-2 towards Sgr A* but is truncatedwithin 1" (0.04pc). We explore the origin of this annulus using a model inwhich star formation occurs in a disk of gas created through the partialcapture of a gas cloud as it sweeps through the inner few parsecs of the galaxyand temporarily engulfs Sgr A*. We identify the locations within which starformation and/or accretion onto Sgr A* take place. Within 0.04 pc the disk ismagnetically active and the associated heating and enhanced pressure preventsthe disk from becoming self gravitating. Instead, it forms a magneto-turbulentdisk that drains onto Sgr A* within 3 Myr. Meanwhile, fragmentation of the gasbeyond the central 0.04 pc hole creates the observed young stellar disk. Thetwo large scale bubbles of gamma-ray emission extending perpendicular to theGalactic plane may be created by a burst of accretion of ~10^5 Msun of gaslying between 0.01 and 0.03 pc. The observed stellar ages imply that thiscapture event occurred ~10^6.5 yr ago, thus such events occurring over the lifetime of the Galaxy could have significantly contributed to the current mass ofSgr A* and to the inner few parsec of the nuclear star cluster. We suggest thatthese events also occur in extragalactic systems.

On the origin of the central 1" hole in the stellar disk of Sgr A* and the Fermi gamma-ray bubbles