Molecular cloud structure traced by submm- and far-IR spectral line observations

Abstract

Submillimeter and far-IR (FIR) spectral line observations are particularly sensitive to molecular cloud surface regions, where the UV radiation from nearby massive, young stars can heat the gas, dissociate the molecules and partly ionize the atoms. Due to the clumpy structure of molecular clouds these interface regions dominate the observed line emission from molecular clouds in the subrnm and FIR spectral range. These observations thus reveal many interesting aspects about the molecular cloud structure, and the way in which newly formed stars affect the physical and chemical conditions in the clumpy cloud core.