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arXiv · 0704.2108

A Near-Infrared Study of the Highly-Obscured Active Star-Forming Region W51B

Hyosun Kim·Yasushi Nakajima·Hwankyung Sung·Dae-Sik Moon·Bon-Chul Koo
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Abstract

We present wide-field JHKs-band photometric observations of the three compact HII regions G48.9-0.3, G49.0-0.3, and G49.2-0.3 in the active star-forming region W51B. The star clusters inside the three compact HII regions show the excess number of stars in the J-Ks histograms compared with reference fields. While the mean color excess ratio E(J-H)/E(H-Ks) of the three compact HII regions are similar to ~ 2.07, the visual extinctions toward them are somewhat different: ~ 17 mag for G48.9-0.3 and G49.0-0.3; ~ 23 mag for G49.2-0.3. Based on their sizes and brightnesses, we suggest that the age of each compact HII region is =< 2 Myr. The inferred total stellar mass, ~ 1.4 x 10^4 M_sun, of W51B makes it one of the most active star forming regions in the Galaxy with the star formation efficiency of ~ 10 %.

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Hyosun Kim, Yasushi Nakajima, Hwankyung Sung, Dae-Sik Moon, Bon-Chul Koo. 2007-04-17. A Near-Infrared Study of the Highly-Obscured Active Star-Forming Region W51B. https://doi.org/10.5303/jkas.2007.40.1.017

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