Astronomy and Astrophysics – Astronomy
Scientific paper
Jun 1982
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1982apj...257..151w&link_type=abstract
Astrophysical Journal, Part 1, vol. 257, June 1, 1982, p. 151-160.
Astronomy and Astrophysics
Astronomy
50
Abundance, Cyanogen, Interstellar Chemistry, Nebulae, Stellar Envelopes, Carbon Stars, Hydrocyanic Acid, Infrared Astronomy, Molecular Clouds, Molecular Structure, Photodissociation
Scientific paper
First observations of the N = 2-1 line of CN at 226.9 GHz are reported. High-resolution maps of IRC + 10216 and OMC-1 show that the peak in both sources is compact but resolved in a 30 arcsec beam. In IRC + 10216 the emission extends approximately 70 arcsec at the line center velocity. A model for CN excitation and the absence of infrared vibration-rotation absorption lines suggest the presence of a source of CN molecules in the outer circumstellar shell. Examination of chemical, expansion, and photodissociation time scales in the outer shell leads to the identification of HCN photodissociation by the interstellar radiation field as a plausible source. This model explains the large discrepancy in the CN abundance predicted by chemical equilibrium models of the shell and confirms the importance of photo-dissociation in the chemistry of circumstellar shells. Maps and spectra were also made in OMC-1 and OMC-2. In OMC-1, CN emission lies along a narrow ridge, peaking in the BN/KL region.
Lichten Stephen M.
Sahai Raghvendra
Wannier Peter G.
Wootten Al
No associations
LandOfFree
CN abundance variations in the shell of IRC +10216 does not yet have a rating. At this time, there are no reviews or comments for this scientific paper.
If you have personal experience with CN abundance variations in the shell of IRC +10216, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and CN abundance variations in the shell of IRC +10216 will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1351544