The Dynamics of Molecular Material within 15 Parsecs of the Galactic Center

Abstract

We report the results of a five-field mosaic of the central 15 pc of the Galaxy in the (1, 1) and (2, 2) lines of NH3. Two narrow filaments or streamers are seen running parallel to the Galactic plane. The southern streamer appears to carry gas directly toward the nuclear region from the 20 km s-1 cloud. The eastern streamer, which we will denote the molecular ridge, appears to be the denser part of the 50 km s-1 cloud that lies immediately east of the Sgr A East complex and extends in the south toward the 20 km s-1 cloud. This ridge of gas carries the kinematical signatures of interactions with Sgr A East as well as a supernova remnant that lies south of the Galactic center. The bulk motion of the gas, the enhanced line widths, and the heating of the molecular material all suggest an active evolutionary phase for the gas immediately adjacent to the nucleus.