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arXiv · 1403.4617

Dust-to-Gas Ratios of the GALFA-HI Compact Cloud Catalog

Destry R. Saul·J. E. G. Peek·M. E. Putman
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Abstract

We have searched for infrared dust emission from subsets of compact, Galactic neutral hydrogen clouds, with the purpose of looking for dust in high-velocity clouds, identifying low-velocity halo clouds, and investigating the cloud populations defined in the GALFA-HI Compact Cloud Catalog. We do not detect dust emission from high-velocity clouds. The lack of dust emission from a group of low-velocity clouds supports the claim that they are low-velocity halo clouds. We detect dust in the remaining low-velocity clouds, indicating a Galactic origin, with a significantly greater dust-to-gas ratio for clouds with linewidths near 15 km/s. We propose that this is due to dust associated with ionized gas.

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Destry R. Saul, J. E. G. Peek, M. E. Putman. 2014-03-18. Dust-to-Gas Ratios of the GALFA-HI Compact Cloud Catalog. https://doi.org/10.1093/mnras%2Fstu498

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