Year: 1982
Type: article
Abstract: We report observations of NGC 6334N, M17 SW, W 51 and DR 21(OH) in the J = 4 → 3 transition of HCN at 354 GHz. These results are combined with previously obtained J = 1 → 0 HCN data to determine molecular abundances X (HCN)|$\sim 4\times{10}^{-11}-4\times{10}^{-12}$|, and characteristic line excitation zone densities n |$(\text{H}_{2})\sim {10}^{6}\,\text{cm}^{-3}$|. These results are at variance with previous analyses based on J = 1 → 0 results alone, and the predictions of certain models of the cloud chemistry. The reasons for these discrepancies are discussed.
Institution: Queen Mary University of London
Language: English
Subfield: Astronomy and Astrophysics
Field: Physics and Astronomy
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2078773343