Astronomy and Astrophysics – Astrophysics
Scientific paper
Apr 1987
adsabs.harvard.edu/cgi-bin/nph-data_query?bibcode=1987a%26a...176..285t&link_type=abstract
Astronomy and Astrophysics (ISSN 0004-6361), vol. 176, no. 2, April 1987, p. 285-293.
Astronomy and Astrophysics
Astrophysics
48
Acetylene, Cyanogen, Interstellar Chemistry, Photochemical Reactions, Radiative Transfer, Stellar Envelopes, Abundance, Hydrocyanic Acid, Line Spectra, Molecular Collisions, Molecular Energy Levels, Molecular Rotation, Molecular Spectra
Scientific paper
The circumstellar envelope of IRC +10216 has been mapped in all hyperfine transitions in the ground state of C2H and CN, using the 20-m Onsala telescope. C2H and CN extend respectively to a radius of ≡50arcsec and 75arcsec. The C2H on-source profiles are double-peaked, typical of an optically thin medium. CN lines are optically thick and some hyperfine components are highly blended. To interpret the observations, the authors use a radiative transfer model including line overlap and photochemistry. C2H and CN are assumed to be, repectively, the by-products of C2H2 and HCN which are photodissociated by ambient UV photons. The shell physical parameters, namely the shielding parameters and molecular abundances are estimated. The best fit with observational data requires a shielding distance for CN, d(CN) = 1.8×1017cm, larger than for HCN, d(HCN) = 1.5×1017cm. The present results are in qualitative agreement with earlier analysis of these species by Huggins et al. (1984).
Johansson Lars E. B.
Nguyen-Q-Rieu
Olofsson Hans
Omont Alain
Truong-Bach
No associations
LandOfFree
The circumstellar shell of IRC + 10216 - Photo-chemistry of C2H and CN 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 The circumstellar shell of IRC + 10216 - Photo-chemistry of C2H and CN, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and The circumstellar shell of IRC + 10216 - Photo-chemistry of C2H and CN will most certainly appreciate the feedback.
Profile ID: LFWR-SCP-O-1346922