other query modes : |
Identifier query |
Coordinate query |
Criteria query |
Reference query |
Basic query |
Script submission |
TAP |
Output options |
Object types |
Help |
2002MNRAS.337.1091S - Mon. Not. R. Astron. Soc., 337, 1091-1104 (2002/December-2)
Evolution and colours of helium-core white dwarf stars: the case of low-metallicity progenitors.
SERENELLI A.M., ALTHAUS L.G., ROHRMANN R.D. and BENVENUTO O.G.
Abstract (from CDS):
We find that most of our evolutionary sequences experience several episodes of hydrogen thermonuclear flashes. In particular, the lower the metallicity, the larger the minimum stellar mass for the occurrence of flashes induced by CNO cycle reactions. The existence of a mass threshold for the occurrence of diffusion-induced CNO flashes leads to a marked dichotomy in the age of our models. Another finding of this study is that our He WD models experience unstable hydrogen burning via PP nuclear reactions at late cooling stages as a result of hydrogen chemically diffusing inwards. Such PP flashes take place in models with very low metal content.
We also find that models experiencing CNO flashes exhibit a pronounced turn-off in most of their colours at MV~ 16. Finally, colour-magnitude diagrams for our models are presented and compared with recent observational data of He WD candidates in the globular clusters NGC 6397 and 47 Tucanae.
Abstract Copyright: RAS
Journal keyword(s): stars: atmospheres - stars: evolution - stars: fundamental parameters - stars: interiors - white dwarfs
Simbad objects: 5
To bookmark this query, right click on this link: simbad:2002MNRAS.337.1091S and select 'bookmark this link' or equivalent in the popup menu