Molecular Gas Feeding the Circumnuclear Disk of the Galactic Center
  The interaction between a supermassive black hole (SMBH) and the surrounding
material is of primary importance in modern astrophysics. The detection of the
molecular 2-pc circumnuclear disk (CND) immediately around the Milky Way SMBH,
SgrA*, provides an unique opportunity to study SMBH accretion at sub-parsec
scales. Our new wide-field CS(2-1) map toward the Galactic center (GC) reveals
multiple dense molecular streamers originated from the ambient clouds 20-pc
further out, and connecting to the central 2 parsecs of the CND. These dense
gas streamers appear to carry gas directly toward the nuclear region and might
be captured by the central potential. Our phase-plot analysis indicates that
these streamers show a signature of rotation and inward radial motion with
progressively higher velocities as the gas approaches the CND and finally ends
up co-rotating with the CND. Our results might suggest a possible mechanism of
gas feeding the CND from 20 pc around 2 pc in the GC. In this paper, we discuss
the morphology and the kinematics of these streamers. As the nearest observable
Galactic nucleus, this feeding process may have implications for understanding
the processes in extragalactic nuclei.
