The chemical state of dense interstellar clouds - An overviewThe currently known interstellar molecules and isotopes are listed, procedures for determining relative chemical abundances in molecular clouds are discussed, and current best estimates for such abundances in regions of differing physical properties are presented. Among the results are a general chemical similarity across a range of density and temperature for quiescent clouds, and some striking differences among regions which are not easily related to such physical parameters and may instead reflect cloud history and evolution. The possibility of constraining chemical models via measurements of relative abundances for the isomeric pairs HNC/HCN, CH3NC/CH3CN, and HOC(+)/HCO(+) is discussed in detail.
Document ID
19860027910
Acquisition Source
Legacy CDMS
Document Type
Conference Proceedings
Authors
Irvine, W. M. (Massachusetts Univ. Amherst, MA, United States)
Schloerb, F. P. (Massachusetts, University Amherst, United States)
Hjalmarson, A. (Onsala Rymdobservatorium Sweden)
Herbst, E. (Duke University Durham, NC, United States)