Circumstellar envelopes and the evolution of carbon stars.
Abstract
A quantitative classification scheme is presented for carbon stars that yields temperature class, carbon class, and C-13 isotopic index, derived from low-resolution image-tube scanner spectra. An absolute magnitude and bolometric luminosity calibration is constructed on the basis of temperature class from information existing in the literature. This scheme is applied to 16 carbon stars that have high infrared luminosity and results in spectral classifications; quantitative estimates of circumstellar extinction, both differential and neutral, assuming that small graphite grains are responsible; individual distances; column masses of graphite; intrinsic fluxes of H-alpha emission; and a possible evolutionary sequence. The hypothesis that hydrogen emission is caused by shock waves is vindicated.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- March 1979
- DOI:
- 10.1093/mnras/186.4.837
- Bibcode:
- 1979MNRAS.186..837C
- Keywords:
-
- Carbon Stars;
- Infrared Astronomy;
- Interstellar Extinction;
- Stellar Envelopes;
- Stellar Evolution;
- Carbon 13;
- Graphite;
- H Alpha Line;
- Stellar Luminosity;
- Stellar Temperature;
- Astrophysics;
- Carbon Stars:Circumstellar Envelopes;
- Carbon Stars:Evolution;
- Carbon Stars:Spectral Classification