Observations of an emission nebula associated with the carbon star UVAur.
Abstract
Optical and UV spectra from the stellar object UV Aur B were analyzed with model atmospheres and in terms of the UV absorption feature. The Coudespectrograph data were obtained with the ESO 1.5 m telescope. Three tracings of the B star spectrum indicated that the Balmer emission lines form in a nebula located between the two stars or mainly from a carbon star. The effective temperature and interstellar reddening of the B star were calculated to be 14,000 K and within 0.02 of 0.21, respectively. The B star rotational velocity was determined to be within 20 km/sec of 170 km/sec. A low value of the Lyman alpha flux indicated that the B star companion of UV Aur was not the ionizing source for the nebula, and the presence of a third star is suggested in the form of hot white dwarf with a temperature of at least 60,000 K.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 1983
- Bibcode:
- 1983A&A...123..257R
- Keywords:
-
- B Stars;
- Carbon Stars;
- Interstellar Radiation;
- Nebulae;
- Stellar Spectra;
- Atmospheric Models;
- Interstellar Extinction;
- Iue;
- Shock Fronts;
- Ultraviolet Absorption;
- Visible Spectrum;
- Astrophysics