2004ApJ...616..865K

We present Antarctic Submillimeter Telescope and Remote Observatory (AST/RO) observations of ¹²CO J=4⟶3 and [C I] emission in the N44 H II complex in the Large Magellanic Cloud. We detected strong ¹²CO J=4⟶3 emission toward the H II region known as N44BC, which is located on the rim of an expanding giant shell in the N44 region. Analysis with a photodissociation region model showed that the ¹²CO J=4⟶3 emitting cloud is very dense, with n₀~10⁵/cm3. We also note that there is a high-velocity component associated with the ¹²CO J=4⟶3 emission. This probably originates from molecular material accelerated as a result of the motion induced by the expanding giant shell surrounding LH 47 in the N44 complex. We found that the kinetic energy of this high-velocity gas observed in the ¹²CO J=4⟶3 emission toward the rim of the expanding H II shell is at least a factor of 4 higher than that derived for the H I and H II gas in this region.