In a J, H, and Ks band survey of the Galactic center region over an area of 2° x 5°, 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 are estimated to be 3.2-4.2kpc, corresponding to the Norma arm, by our new method for determining the distances to dark clouds using the cumulative number of stars against the J - Ks color. By adopting these estimated distances, the size and total mass of the cloud are estimated to be ̃ 70 pc in length and 6 x 104 MG, respectively. Three compact H II regions exist 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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