SuperCAM CO(3-2) APEX survey in SMC

For the identification of the CO(3-2) clouds, we used the CPROPS algorithm, which allowed us to measure the physical properties of the clouds. We analyzed the scaling relationships of such physical properties. We obtained R_32_=0.65+/-0.02 for the SW bar and a slightly higher ratio, R_32_=0.7+/-0.1; for N66 in the SMC.We found that R_32_ varies from region to region, depending on the star formation activity.

In regions dominated by HII and photo-dissociated regions (e.g., N22, N66) R_32) tends to be higher than the median values. Meanwhile, lower values were found toward quiescent clouds.We also found that R_32_ is correlated with the IR color [70/160] and the total IR surface brightness. This finding indicates that R_32_ increases with environmental properties, such as the dust temperature, total gas density, and radiation field.

We identified 225 molecular clouds with sizes of R>1.5pc and signal-to-noise ratios (S/N) of >3, of which only 17 are well resolved CO(3-2) clouds with S/N>~5. These 17 clouds follow consistent scaling relationships to the inner Milky Way clouds but with some departures. For instance, CO(3-2) tends to be less turbulent and less luminous than the inner Milky Way clouds of similar sizes.

Finally, we estimated a median virial-based CO(3-2)-to-H_2_ conversion factor of 12.6^+10^_-7^M_{sun}_ (K.km/s/pc^2^)^-1^ for the total sample.