First Results of a CO Survey of the Small Magellanic Cloud with NANTEN

Abstract

Abstract We present the first results from a new 12CO ($J = 1 \hbox{--} 0$) survey of the Small Magellanic Cloud (SMC) with the NANTEN millimeter-wave telescope. The survey covered the northeast and southwest regions of the main Bar, and the H ii regions N 84, N 88 in the Wing at a linear resolution of $\sim 50 \,\mathrm{pc}$. Twenty-one giant molecular clouds (GMCs), whose masses are $\sim 10^{4} \hbox{--} 10^{6} \,{{{M}_{\odot}}}$, were identified. Significant CO emission, $T_\mathrm{R}^{\ast} \sim 0.36 \,\mathrm{K}$, was first detected toward the N 84 region in the Wing, which is comparable to those of the prominent CO clouds associated with infrared sources LIRS 36, LIRS 49 in the Bar. The GMCs exhibit a good spatial correlation with the H ii regions and young clusters, indicating that cluster formation is on-going in these GMCs. On the other hand, they show little correlation with older clusters or with supernova remnants, suggesting rapid dissipation of CO.