The scale height of giant molecular clouds is less than that of smaller clouds

An antenna temperature thresholding algorithm is used on the Bell Laboratories (CO)-C-13 J = 1 --> 0 Milky Way Survey to create a catalog of 1400 molecular clouds. Of these, 281 clouds are selected for having well- determined kinematic distances. The scale height, luminosity, internal velocity dispersion, and size of the cloud sample are analyzed to show that clouds smaller than similar to10(5.5) M-. have a scale height which is about 35 pc, roughly independent of cloud mass, while larger clouds, the giant molecular clouds, have a reduced scale height which declines with increasing cloud mass.