Observations of 13.5 Micron Rotation-Vibration Lines of SiS in IRC +10216
Abstract
We report the first observations of the 13.5 micron fundamental band of SiS in the spectrum of the heavily obscured carbon star IRC +10216. The lines are formed in the inner region of the circumstellar envelope where the gas is accelerating and where the temperature ranges from 800-500 K. We have carried out a detailed model of the observed line profiles. Our observations are best fit by a gradient in the abundance of SiS. We derive an abundance relative to molecular hydrogen of x(SiS) = 4.3 x 10-6 at a distance of twelve stellar radii from the central star rising to x(SiS) = 4.3 x 10-5 at a few stellar radii from the surface of the star.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- January 1994
- DOI:
- 10.1086/173609
- Bibcode:
- 1994ApJ...420..863B
- Keywords:
-
- Carbon Stars;
- Stellar Envelopes;
- Stellar Models;
- Variable Stars;
- Abundance;
- Fourier Transformation;
- Line Spectra;
- Temperature Distribution;
- Astronomy;
- MOLECULAR PROCESSES;
- STARS: ABUNDANCES;
- STARS: CARBON;
- STARS: CIRCUMSTELLAR MATTER;
- STARS: INDIVIDUAL ALPHANUMERIC: IRC;
- 10420