Kinematics of the H II region sharpless 142. III - Molecular line observations and analysis of the IRAS data

The molecular cloud associated with the H II region S142 has been mapped in the J = 1-0 transition lines of (C-12)O and (C-13)O. It is found that the molecular cloud has two components separated by 25 parsecs and has a total mass of about 5600 solar masses. High-resolution observations in these transition lines reveal the presence of condensations in the molecular cloud. An analysis of IRAS data is presented, showing that the IR thermal continuum emission has a larger extent at 100 microns than at 12 microns. The mean dust color temperature is shown to be 169 K for the hot, small grains, and 34 K for the colder, larger grains. It is shown that the total dust mass is about 60 solar masses and the total IR flux is 8.5 + or - 0.8 X 10 to the -10 W/sq m. A gas-to-dust ratio of about 200 is derived for the gas complex S142. A mass of 1000 solar masses is found for the stellar cluster associated with S142. The star formation efficiency for the S142 gas complex is estimated at about 8 percent.