Atmospheric parameters and mass distribution of DA white dwarfs.
Abstract
A comprehensive evaluation of existing observational data on DA white dwarfs is performed by using a weighted least-squares technique and a set of model atmospheres. A mass distribution is determined and found to be rather narrow, with two-thirds of the stars within + or - 0.12 solar mass or less of the mean mass of 0.58 solar mass. Most of the DA white dwarfs are shown to fall into the mass range from 0.46 to 0.07 solar mass. The smallness of the DA masses relative to the Chandrasekhar limit or the mass of the binary companion Sirius B (1 solar mass) is explained on the basis of the core mass-luminosity relation in the double-shell-burning phase. It is concluded that the observed narrow mass distribution of DA white dwarfs is an important constraint on schemes of stellar and galactic evolution.
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- July 1979
- Bibcode:
- 1979A&A....76..262K
- Keywords:
-
- Atmospheric Models;
- Mass Distribution;
- Stellar Atmospheres;
- Stellar Evolution;
- White Dwarf Stars;
- Graphs (Charts);
- High Resolution;
- Least Squares Method;
- Stellar Spectrophotometry;
- Tables (Data);
- Ubv Spectra;
- Astrophysics;
- Atmospheres:White Dwarfs;
- HR Diagrams:White Dwarfs;
- Magnitudes:White Dwarfs;
- Temperatures:White Dwarfs;
- Two-Color Diagrams:White Dwarfs