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arXiv · 1102.2533

Properties of the Compact HII Region Complex G-0.02-0.07

Elisabeth Mills·Mark R. Morris·Cornelia Lang·Hui Dong·Q. Daniel Wang·Angela Cotera·Susan Stolovy
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Abstract

We present new extinction maps and high-resolution Paschen alpha images of G-0.02-0.07, a complex of compact HII regions located adjacent to the M-0.02-0.07 giant molecular cloud, 6 parsecs in projection from the center of the Galaxy. These HII regions, which lie in projection just outside the boundary of the Sgr A East supernova remnant, represent one of the most recent episodes of star formation in the central parsecs of the Galaxy. The 1.87 micron extinctions of regions A, B and C are almost identical, approximately 1.5 magnitudes. Region D, in contrast, has a peak 1.87 micron extinction of 2.3 magnitudes. Adopting the Nishiyama et al. (2008) extinction law, we find these extinctions correspond to visual extinctions of A_V = 44.5 and A_V = 70, respectively. The similar and uniform extinctions of regions A, B and C are consistent with that expected for foreground extinction in the direction of the Galactic center, suggesting that they lie at the front side of the M-0.02-0.07 molecular cloud. Region D is more compact, has a higher extinction and is thus suspected to be younger and embedded in a dense core in a compressed ridge on the western edge of this cloud.

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Elisabeth Mills, Mark R. Morris, Cornelia Lang, Hui Dong, Q. Daniel Wang, Angela Cotera, Susan Stolovy. 2011-02-12. Properties of the Compact HII Region Complex G-0.02-0.07. https://doi.org/10.1088/0004-637x%2F735%2F2%2F84

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