A study of DCO+ emission regions in interstellar clouds

Abstract

view Abstract Citations (96) References (45) Co-Reads Similar Papers Volume Content Graphics Metrics Export Citation NASA/ADS A study of DCO+ emission regions in interstellar clouds. Wootten, A. ; Loren, R. B. ; Snell, R. L. Abstract Observations of the J = 1-0 lines of HCO(+), (H-13)CO(+), and DCO(+) and of the J = 2-1 line of DCO(+) taken with similar beam sizes are used in constructing models of the DCO(+) emission regions in eleven molecular clouds. The densities and extents of the regions as determined from the DCO(+) observations are similar to the densities and extents of the same regions modeled on formaldehyde observations. The DCO(+)/(H-13)CO(+) abundance ratio ranges from 0.2 to 6 in this sample. The observations, interpreted in the light of newly measured reaction rates, constrain electron abundances in some regions to be very low, X(e) being less than 1 x 10 to the -7. Independent limits placed on X(e) using (C-13)O and (H-13)CO(+) observations yield more sensitive limits, X(e) being less than 6 x 10 to the -8. It is found that carbon monoxide abundance limits are consistent with those found at the edges of dark clouds. Publication: The Astrophysical Journal Pub Date: April 1982 DOI: 10.1086/159814 Bibcode: 1982ApJ...255..160W Keywords: Astronomical Models; Deuterium Compounds; Emission Spectra; Interstellar Matter; Line Spectra; Molecular Clouds; Abundance; Carbon Monoxide; Formic Acid; Interstellar Chemistry; Positive Ions; Radiative Transfer; Reaction Kinetics; Temperature Dependence; Astrophysics full text sources ADS | data products SIMBAD (27) NED (1)