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arXiv · 0811.2789

The Dust-to-Gas Ratio in the Small Magellanic Cloud Tail

K. D. Gordon·C. Bot·E. Muller·K. A. Misselt·A. Bolatto·J. -P. Bernard·W. Reach·C. W. Engelbracht·B. Babler·S. Bracker·M. Block·G. C. Clayton·J. Hora·R. Indebetouw·F. P. Israel·A. Li·S. Madden·M. Meade·M. Meixner·M. Sewilo·B. Shiao·L. J. Smith·J. Th. van Loon·B. A. Whitney
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Abstract

The Tail region of the Small Magellanic Cloud (SMC) was imaged using the MIPS instrument on the Spitzer Space Telescope as part of the SAGE-SMC Spitzer Legacy. Diffuse infrared emission from dust was detected in all the MIPS bands. The Tail gas-to-dust ratio was measured to be 1200 +/- 350 using the MIPS observations combined with existing IRAS and HI observations. This gas-to-dust ratio is higher than the expected 500-800 from the known Tail metallicity indicating possible destruction of dust grains. Two cluster regions in the Tail were resolved into multiple sources in the MIPS observations and local gas-to-dust ratios were measured to be ~440 and ~250 suggests dust formation and/or significant amounts of ionized gas in these regions. These results support the interpretation that the SMC Tail is a tidal tail recently stripped from the SMC that includes gas, dust, and young stars.

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K. D. Gordon, C. Bot, E. Muller, K. A. Misselt, A. Bolatto, J. -P. Bernard, W. Reach, C. W. Engelbracht, B. Babler, S. Bracker, M. Block, G. C. Clayton, J. Hora, R. Indebetouw, F. P. Israel, A. Li, S. Madden, M. Meade, M. Meixner, M. Sewilo, B. Shiao, L. J. Smith, J. Th. van Loon, B. A. Whitney. 2008-11-17. The Dust-to-Gas Ratio in the Small Magellanic Cloud Tail. https://doi.org/10.1088/0004-637x/690/1/l76

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