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arXiv · 0812.0865

A Chain of Dark Clouds in Projection Against the Galactic Center

Takahiro Nagayama·Shuji Sato·Shogo Nishiyama·Yuka Murai·Tetsuya Nagata·Hirofumi Hatano·Mikio Kurita·Motohide Tamura·Yasushi Nakajima·Koji Sugitani·Tomoharu Oka·Yoshiaki Sofue
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Abstract

In the J, H, and Ks bands survey of the the Galactic Center region over an area of 2deg x 5deg, we have found many dark clouds, among which a distinguished chain of dark clouds can be identified with a quiescent CO cloud. The distances of the clouds is estimated to be 3.2-4.2 kpc, corresponding to the Norma arm by our new method to determine distance to dark clouds using the cumulative number of stars against J-Ks colors. Adopting these estimated distances, the size is about 70 pc in length and the total mass of the cloud is 6x10^4 M_solar. Three compact HII regions harbor in the cloud, indicating that star forming activities are going on at the cores of the quiescent CO cloud on the spiral arm.

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Takahiro Nagayama, Shuji Sato, Shogo Nishiyama, Yuka Murai, Tetsuya Nagata, Hirofumi Hatano, Mikio Kurita, Motohide Tamura, Yasushi Nakajima, Koji Sugitani, Tomoharu Oka, Yoshiaki Sofue. 2008-12-04. A Chain of Dark Clouds in Projection Against the Galactic Center. https://doi.org/10.1093/pasj%2F61.2.283

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