Results of the ESO-SEST Key Programme on CO in the Magellanic Clouds. I : A survey of CO in the LMC and the SMC

As the first part of the ESO-Swedish SEST Key Programme on CO in the Magellanic Clouds, we have observed 12 CO J=1-0 towards 92 positions in the LMC and 42 positions in the SMC. In the SMC we searched for emission form H II regions, dark clouds and IRAS infrared sources. The generally negative detection rate of non-IRAS sources in the SMC led to an LMC source selection based on the IRAS results. In both galaxies, CO was detected towards the majority of sources observed. We also observed 13 CO J=1-0 towards the brighter 12 CO sources in the LMC (37) and SMC (9). Compared to the strength of CO lines observed in the Milky Way Galaxy with identical linear resolutions, velocity-integrated CO emission is weaker by at least a factor of three in the LMC sources and an order of magnitude in the SMC sources