MULTIWAVELENGTH OBSERVATIONS OF 2 B-STAR NURSERIES - DR-15 AND DR-20

In this article, we present a collection of new observations of DR 15 and 20 utilizing recent far-infrared, radio, and molecular line data as part of a study of compact H II regions in the Cygnus X region. The radio and far-IR data for these objects, when combined with 12CO maps, IRAS imagery, and optical photographs provide new insights into the structure of this complex region, and the nature of the starformation process there. Our observations show that DR 15 may consist of one or two BO ZAMS stars whose H I regions have formed a low density cavity within a molecular cloud. DR 20 appears to be a young OB cluster. The cluster is dominated by an O5.5 ZAMS star and also contains an ∼3500 yr old BO star appearing as a compact H II region, along with weak far-IR sources that may be BO-star candidates. We discuss the physical properties and kinematics of the DR 15 and 20 OB clusters in light of our multiwavelength data, and propose that cloud-cloud collisions may have been responsible for triggering the star-formation episodes in these sources.