R Aquarii : an attempt at a unified model.
Abstract
Consideration is given to a new model of R Aqr in which the binary system is composed of an M7 Mira with a mass of about 1.5 solar mass, a temperature of about 2800 K, a bolometric magnitude of about -4.56, and a radius of about 300 solar radii, plus a hot stellar source in an intermediate phase between a subdwarf and a white dwarf with a radiation temperature of 40,000 K, a luminosity of 10 solar luminosities, and a radius of greater than about 0.1 solar radii. A plausible origin for the jet is a spherically symmetric stellar wind, blowing out with a high velocity and mass loss rate and evacuating a cavity in an ambient medium with anisotropic density and pressure. This resulting bubble elongates in the directions of least resistance, and matter eventually flows out through two symmetric nozzles. Interaction with the outer medium then further collimates the jet. Detailed comparisons with theoretical models show that the emission in the NE and SW outer features of the jets is due to a radiative shock.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- August 1992
- Bibcode:
- 1992A&A...262...83B
- Keywords:
-
- Accretion Disks;
- Binary Stars;
- Stellar Models;
- Symbiotic Stars;
- Interstellar Matter;
- Radio Jets (Astronomy);
- Shock Waves;
- Ultraviolet Astronomy;
- Astrophysics