The Two Young Star Disks in the Central Parsec of the Galaxy: Properties, Dynamics, and Formation

We report the definite spectroscopic identification of ’40 OB supergiants, giants, and main-sequence stars in the central parsec of the Galaxy. Detection of their absorption lines has become possible with the high spatial and spectral resolution and sensitivity of the adaptive optics integral field spectrometer SPIFFI/SINFONI on the ESO VLT. Sev-eral of these OB stars appear to be helium- and nitrogen-rich. Almost all of the’80 massive stars now known in the central parsec (central arcsecond excluded) reside in one of two somewhat thick (h hj j/Ri ’ 0:14) rotating disks. These stellar disks have fairly sharp inner edges (R ’ 100) and surface density profiles that scale as R2. We do not detect any OB stars…