Dust Temperatures in the Circumstellar Shell of TX PISCIUM
Abstract
A suitable chromospheric model is used to study the interaction of the chromospheric UV radiation with the envelope of the cool carbon-rich star TX Psc. The temperature T(d) of the amorphous carbon grains as a function of the various locations in the internal layer of the circumstellar shell is calculated. The dust temperature decreases from T(d) = 1155 K at r = 2.25 R(stellar) to T(d) = 410 K at r = 30 R(stellar). The far-infrared flux is calculated and compared with observations of IRS data. The contribution of the dust heating by the chromosphere is low. The properties of the chromospheric model used here are discussed and compared with other semiempirical chromospheric models of TX Psc. Finally, the photodestruction rate of H2 illuminated by the chromospheric UV radiation field is determined, and it is concluded that H2 is photodestructed.
- Publication:
-
The Astrophysical Journal
- Pub Date:
- August 1991
- DOI:
- 10.1086/170358
- Bibcode:
- 1991ApJ...377..285W
- Keywords:
-
- Carbon Stars;
- Chromosphere;
- Cool Stars;
- Cosmic Dust;
- Stellar Envelopes;
- Ultraviolet Radiation;
- Computational Astrophysics;
- Far Infrared Radiation;
- Infrared Astronomy Satellite;
- Temperature;
- Astrophysics;
- STARS: CARBON;
- STARS: CHROMOSPHERES;
- STARS: CIRCUMSTELLAR SHELLS;
- STARS: INDIVIDUAL CONSTELLATION NAME: TX PISCIUM