2006A&A...454L..67S

This paper presents new APEX submillimetre molecular line observations of three low-mass protostars, IRS7A, IRS7B, and IRAS32, in the R Coronae Australis molecular cloud complex. The molecular excitation analysis is performed using a statistical equilibrium radiative transfer code. The derived beam averaged fractional abundances vary by less than a factor of two among the three sources, except those of H₂CO and CH₃OH, which show differences of about an order of magnitude. The molecular abundances are similar to those typically found in other star-forming regions in the Galaxy, such as the ρ Oph and Perseus molecular clouds. There is a marked difference in the kinetic temperatures derived for the protobinary source IRS7 from H₂CO (≃40-60K) and CH₃OH (≃20K), possibly indicating a difference in origin of the emission from these two molecules.