A (C-12)O survey of the Small Magellanic Cloud

Abstract

The central 2 arcsec x 2 arcsec region of the SMC has been fully surveyed to search for (C-12)O emission in the J = 1-0 transition. (C-12)O emission from two large complexes located in the southwest and northeast regions of the SMC Bar was detected. The molecular clouds appear to be invariably associated with regions of recent star formation. The (C-12)O antenna temperatures of the SMC moleular clouds are extremely weak. The CO sources are usually projected in the direction of H I clouds with the largest column densities. It is suggested that the molecular clouds are the dense cores of large and massive regions of H I gas that are shielded from the UV radiation pervading the SMC. For the SMC, the conversion factor to derive molecular masses from the velocity-integrated CO emission is found to be 6 x 10 to the 21st/sq cm/K/km s.