IRAC Observations of CO J = 4 → 3 High‐Velocity Cloud in the 30 Doradus Complex in the Large Magellanic Cloud

Abstract

We present the results of 12 CO J = 2 → 1 observations of the X-ray-bright giant shell complex 30 Doradus in the Large Magellanic Cloud (LMC ) using the Antarctic Submillimeter Telescope and Remote Observatory (AST/RO). This is the one of the largest H II complexes in the Local Group. We compare the 12 CO J = 2 → 1 observations against previously made 12 CO J = 4 → 3 observations and analyze the spatial distribution of young stellar objects (YSOs) within the cloud using the Spitzer IRAC observations of the 30 Doradus complex. Both peaks of 12 CO J = 2 → 1 and J = 4 → 3 emitting clouds coincide with the densest region of the filaments in which multiple shells are colliding. The YSOs are clustered in the southern ridge of the warm and dense molecular gas clouds traced by 12 CO J = 4 → 3, indicating a filamentary structure of star formation throughout 30 Doradus. We also find an excess of Class IYSO candidates close to the clouds, which likely represent the most recent phase of star formation in this region. This is a region where the triggered star formation has actually occurred, and newly formed stars may have produced such a high-velocity outflow through interacting with the surrounding molecular cloud material. © 2007. The American Astronomical Society. All rights reserved.