Issue |
A&A
Volume 427, Number 3, December I 2004
|
|
---|---|---|
Page(s) | 923 - 932 | |
Section | Stellar structure and evolution | |
DOI | https://doi.org/10.1051/0004-6361:20040416 | |
Published online | 16 November 2004 |
Pulsations of massive ZZ Ceti stars with carbon/oxygen and oxygen/neon cores
1
Facultad de Ciencias Astronómicas y Geofísicas, Universidad Nacional de La Plata, Paseo del Bosque, s/n, (1900) La Plata, Argentina e-mail: [acorsico;althaus]@fcaglp.unlp.edu.ar
2
Instituto de Astrofísica La Plata, IALP, CONICET, Argentina
3
Departament de Física Aplicada, Universitat Politècnica de Catalunya, Av. del Canal Olímpic, s/n, 08860 Castelldefels, Spain e-mail: garcia@fa.upc.es;isern@ieec.fcr.es
4
Institut d'Estudis Espacials de Catalunya, Ed. Nexus, c/Gran Capità 2, 08034 Barcelona, Spain
5
Institut de Ciències de l'Espai (CSIC)
Received:
10
March
2004
Accepted:
16
July
2004
We explore the adiabatic pulsational properties of massive white dwarf stars with hydrogen-rich envelopes and oxygen/neon and carbon/oxygen cores. To this end, we compute the cooling of massive white dwarf models for both core compositions taking into account the evolutionary history of the progenitor stars and the chemical evolution caused by time-dependent element diffusion. In particular, for the oxygen/neon models we adopt the chemical profile resulting from repeated carbon-burning shell flashes expected in very massive white dwarf progenitors. For carbon/oxygen white dwarfs we consider the chemical profiles resulting from phase separation upon crystallization. For both compositions we also take into account the effects of crystallization on the oscillation eigenmodes. We find that the pulsational properties of oxygen/neon white dwarfs are noticeably different from those made of carbon/oxygen, thus making asteroseismological techniques a promising way to distinguish between the two types of stars and, hence, to obtain valuable information about their progenitors.
Key words: stars: evolution / stars: white dwarfs / stars: oscillations
© ESO, 2004
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.