A study of the molecular cloud toward the HII regions S 35 and S 37 with NANTEN

We have made new observations of a large field of similar to 10 square degr ees toward the two southern HII regions S 35 and S 37. Observations were ma de in the (CO)-C-12, (CO)-C-13, and (CO)-O-18 J = 1-0 emission with the NAN TEN telescope at Las Campanas, Chile. These observations have revealed a gi ant molecular cloud of similar to 1.3 x 10(5) M. in (CO)-C-12, highly elong ated with a size of similar to 80 pc x similar to 20 pc, where a previously known active site of star formations, including GGD 27 IRS and HH 80/81, i s located. The cloud appears lifted up to z similar to 100 pc from the gala ctic plane at an inclination angle of similar to 70 degrees, exhibiting ind ications of strong interactions with the HII regions. Star formation has be en found to be very active in the cloud. We have discovered 4 molecular out flows driven by luminous far-infrared sources of similar to 10(2)-10(4) L. in addition to that previously known toward GGD 27 IRS. The activity is als o demonstrated by the existence of several dense (CO)-O-18 clumps whose mas s ranges from similar to 3 x 10(2) M. to similar to 4 x 10(3) M.. The five molecular outflows are embedded in these (CO)-O-18 clumps. In addition, a c omparison with HI shows that the CO cloud is located at the edge of an HI h ole of similar to 55 pc radius. Since the HI gas surrounding the hole shows a signature of expansion at several km s(-1), we suggest that the HI hole represents a supershell created by some explosive events; like supernova ex plosions; during the last similar to 4 x 10(6) yr. This supershell may also provide an explanation for the origin of the molecular distribution.