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Description
The first 1.1mm continuum survey toward the Small Magellanic Cloud (SMC) was performed using the AzTEC instrument installed on the ASTE 10m telescope. This survey covered 4.5deg^2^ of the SMC with 1{sigma} noise levels of 5-12mJy/beam, and 44 extended objects were identified. The 1.1mm extended emission has good spatial correlation with Herschel 160{mu}m, indicating that the origin of the 1.1mm extended emission is thermal emission from a cold dust component. We estimated physical properties using the 1.1mm and filtered Herschel data (100, 160, 250, 350, and 500{mu}m). The 1.1mm objects show dust temperatures of 17-45K and gas masses of 4x10^3^-3x10^5^M_{sun}_, assuming single-temperature thermal emission from the cold dust with an emissivity index, {beta}, of 1.2 and a gas-to-dust ratio of 1000. These physical properties are very similar to those of giant molecular clouds (GMCs) in our galaxy and the Large Magellanic Cloud. The 1.1mm objects also displayed good spatial correlation with the Spitzer 24{mu}m and CO emission, suggesting that the 1.1mm objects trace the dense gas regions as sites of massive star formation. The dust temperature of the 1.1mm objects also demonstrated good correlation with the 24{mu}m flux connected to massive star formation. This supports the hypothesis that the heating source of the cold dust is mainly local star-formation activity in the 1.1mm objects. The classification of the 1.1mm objects based on the existence of star-formation activity reveals the differences in the dust temperature, gas mass, and radius, which reflects the evolution sequence of GMCs.
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