Submillimetre co rotational lines from dense cores in molecular clouds

Abstract

A simple, spherically-symmetric, centrally-condensed model is constructed for a dense core in a molecular cloud. Optical depths and peak brightness temperatures are calculated for the 10 lowest rotational transitions of carbon monoxide. The cloud, using parameters given by observation for dark condensations in molecular clouds, turns out to be optically thin in these transitions, which allows the maximum density and density distribution to be estimated.