The circumstellar gas cloud around Beta Pictoris. II.
Abstract
An analysis of high-quality echelle spectra of Beta Pic, obtained in October 1984 and March 1985 using the 1.4 m La Silla ESO telescope, indicates that the K line of Ca II is wider than the D lines of Na I, and that a velocity difference of 2 km/s exists between the approximate centers of the lines of the two species. In the circumstellar disk around Beta Pic, it is suggested that the Na I is located in an outer region which contains nearly all of the mass of the disk, and that most of the Ca II lies in an inner region having a 2 km/s redshift with respect to the outer one. Assuming a power law distribution of the total gas density throughout the disk, the gas extends inward to a radius of about 0.4 AU, and the interior region consists of a thin annulus of gas having a solar abundance of calcium.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- October 1986
- Bibcode:
- 1986A&A...167..325V
- Keywords:
-
- Early Stars;
- Extrasolar Planets;
- Infrared Spectra;
- Stellar Envelopes;
- Stellar Spectra;
- Calcium;
- Line Spectra;
- Sodium;
- Stellar Models;
- Astrophysics;
- Circumstellar Matter:Calcium Lines;
- Circumstellar Matter:Sodium Lines