EDP Sciences Journals List
Advanced Search
Subscriber Authentication Point
Home All issues Volume 427/3 Article
Free access article

Issue A&A
Volume 427, Number 3, December I 2004
Page(s) 923 - 932
Section Stellar structure and evolution
DOI http://dx.doi.org/10.1051/0004-6361:20040416



A&A 427, 923-932 (2004)
DOI: 10.1051/0004-6361:20040416

Pulsations of massive ZZ Ceti stars with carbon/oxygen and oxygen/neon cores

A. H. Córsico1, 2, E. García-Berro3, 4, L. G. Althaus1, 2, 3 and J. Isern3, 5

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)

Abstract
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

SIMBAD Objects



© ESO 2004


What is OpenURL?

The OpenURL standard is a protocol for transmission of metadata describing the resource that you wish to access. An OpenURL link contains article metadata and directs it to the OpenURL server of your choice. The OpenURL server can provide access to the resource and also offer complementary services (specific search engine, export of references...). The OpenURL link can be generated by different means.
  • If your librarian has set up your subscription with an OpenURL resolver, OpenURL links appear automatically on the abstract pages.
  • You can define your own OpenURL resolver with your EDPS Account. In this case your choice will be given priority over that of your library.
  • You can use an add-on for your browser (Firefox or I.E.) to display OpenURL links on a page (see http://www.openly.com/openurlref/). You should disable this module if you wish to use the OpenURL server that you or your library have defined.