White Dwarf External Layers. III. Accretion and Related Problems
Abstract
Summary. We have examined the possibility that the differences in the atmospheric composition of white dwarfs (H- or He-rich) could be ascribed to accretion and/or mixing processes. Models of white dwarf Heenvelopes have been constructed, with an H4ayer superimposed, making several assumptions about the H-mass, the metal content, the mixing length and the total mass of the star. It is shown that differences between H-rich and He-rich spectra cannot merely be due to accretion and mixing processes, and that very low accretion rates only are not inconsistent with the existence of He-atmospheres. Key words: accretion white dwarfs conve ction
- Publication:
-
Astronomy and Astrophysics
- Pub Date:
- November 1975
- Bibcode:
- 1975A&A....44..253D