Molecules in Circumstellar Envelopes of Carbon Stars

Abstract

We have searched for line emission from various transitions of a number of molecules, including CO, HCN, CN, CS and SiO, as well as some of their isotopic variants, towards a sample of 68 bright carbon stars. Part of the data has already been published in Olofsson et al. (1993a,b). The aim of the project is to obtain a better understanding of the carbon star phenomenon and the processes involved. In particular, we would like to obtain reliable mass loss rates and molecular abundances for these objects. This requires careful and detailed modelling, which is currently underway. Our hope is that the study of these bright carbon stars will serve as a guide to the study of higher mass loss rate objects. Some preliminary observational results are presented here.