Infalling gas toward the Galactic center

VLA maps of ammonia emission were made for the Galactic center region. The NH3(1, 1) and NH3(2, 2) transitions were observed in three 2' x 2' fields c overing Sgr A* and the region 3' immediately south of it. In the central 3 pc surrounding Sgr A* we find emission that appears to be associated with t he circumnuclear disk (CND), both morphologically and kinematically;This ce ntral emission is-connected to a long, narrow 2 pc x 10 pc streamer of clum py molecular gas located toward the south, which appears to be carrying gas from the nearby 20 km s(-1) giant molecular cloud (GMC) to the circumnucle ar region. We find a velocity gradient along the streamer, with, progressiv ely higher velocities as the gas approaches Sgr A*. The streamer stops at t he location of the CND, where the line width of the NH3 emission increases dramatically. This may be the kinematic signature of accretion onto the CND . The ratio of the NH3(2, 2)/NH3(1, 1) emission indicates that the gas is h eated at the northern tip of the streamer, located inside the eastern edge of the CND. The morphology, kinematics, and temperature gradients of the ga s all indicate that the southern streamer is located at the Galactic center and is interacting with the circumnuclear region.