Molecular clouds in the Galactic center region are distributed mainly along the Galactic plane and have filamentary shapes with several clumps (Bally et al. 1987, Tsuboi et al. 1989). The “50-km.s−1 molecular cloud (M-0.02-0.07)”, which is located ~3’ east from Sgr A West, is one of most remarkable clumps on these molecular filaments. The intimate relation between this cloud and Sgr A East has been mentioned by many authers (e.g. Ho et al. 1986). Several compact HII regions are located toward the cloud (Ekers et al. 1983). The recombination line velocities correspond to the molecular line velocities in the cloud (Goss et al. 1987). Thus this cloud is one of active star forming regions near the Galactic center.

We observed the 50-km-s−1 molecular cloud in CS J=1-0 emission line (48.991 GHz) using the Nobeyama Millimeter Array (NMA) to reveal the detailed structure of the star forming regions near the Galactic center.

We present 6″ (460 pc at a distance of 9.6 Mpc) resolution CO(J=1−0) map of the central region of the grand-design spiral galaxy M51 and very preliminary 4″ (180pc) resolution CO(J=1−0) map of the arm regions, using the Nobeyama Millimeter Array (NMA). The central 3kpc region (1') was mapped with a velocity resolution of 20km/s, and the rest with 10km/s.

We have observed the 12CO (Ishizuki et al 1990) and 13CO emission of the central 65″ region of the galaxy IC342 at the high resolutions of 2.4″ for 12CO and 5.1″×4.2″ for 13CO using the Nobeyama Millimeter Array. The integrated intensities of 12CO and 13CO emission are shown in Fig.1 and 2, respectively.