Metals in IRC +10216 : detection of NaCl, AlCl, and KCl, and tentative detection of alf.
Abstract
The authors report the first detection of metal halides in IRC +10216. The millimetre-wave line profiles suggest that these species are concentrated in the inner circumstellar envelope. The abundances derived for NaCl, AlCl, KCl, and tentatively for AlF, are in the range 1012 - 1014cm-2 and are 106 - 108times lower than the abundance of H2. They agree with the chemical equilibrium abundances calculated by Tsuji (1973) for a carbon-rich stellar atmosphere with a temperature 1200 - 1500K. The lines of NaCl and AlCl, observed with the IRAM 30m telescope, are strong enough to allow the detection of these species' rare 37Cl isotopes. The derived 35Cl/37Cl isotopic ratio (2.3±0.5) is consistent with the terrestrial elemental isotopic ratio.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- September 1987
- Bibcode:
- 1987A&A...183L..10C
- Keywords:
-
- Abundance;
- Astronomical Spectroscopy;
- Infrared Sources (Astronomy);
- Metal Halides;
- Stellar Atmospheres;
- Stellar Envelopes;
- Aluminum Chlorides;
- Aluminum Fluorides;
- Interstellar Matter;
- Line Spectra;
- Potassium Chlorides;
- Sodium Chlorides;
- Astrophysics