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arXiv · 0805.2337

Spitzer Mid-infrared Study of Compact HII Regions in the Magellanic Clouds

V. Charmandaris·M. Heydari-Malayeri·E. Chatzopoulos
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Abstract

We present a study of the mid-infrared properties and dust content of a sample of 27 HII ``blobs'', a rare class of compact HII regions in the Magellanic Clouds. A unique feature of this sample is that even though these HII regions are of high and low excitation they have nearly the same physical sizes ~1.5-3 pc. We base our analysis on archival 3-8 microns infrared imagery obtained with the Infrared Array Camera (IRAC) on board the Spitzer Space Telescope. We find that despite their youth, sub-solar metallicity and varied degrees of excitation, the mid-infrared colors of these regions are similar to those of typical HII regions. Higher excitation ``blobs'' (HEBs) display stronger 8 micron emission and redder colors than their low-excitation counterparts (LEBs).

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V. Charmandaris, M. Heydari-Malayeri, E. Chatzopoulos. 2008-05-15. Spitzer Mid-infrared Study of Compact HII Regions in the Magellanic Clouds. https://doi.org/10.1051/0004-6361%3A200809662

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