A nonadiabatic oscillation study of DB white dwarfs

被引:22
作者
Gautschy, A [1 ]
Althaus, LG [1 ]
机构
[1] Natl Univ La Plata, Fac Ciencias Astron & Geofis, RA-1900 La Plata, Argentina
关键词
stars : oscillations; stars : white dwarfs; stars : interior;
D O I
10.1051/0004-6361:20011607
中图分类号
P1 [天文学];
学科分类号
0704 ;
摘要
A self-consistent abundance diffusion treatment in the evolution of cooling white dwarfs permitted a study of the effect of elemental segregation in nonadiabatic, nonradial stability computations. In particular, mode trapping manifesting itself in cyclically varying period separations behaved differently from its appearance in the damping/excitation rates. Another aspect of the investigation concerned the effect of heavy-element traces in homogeneous DB white-dwarf envelopes on their pulsational instability domain. The stellar models are computed with the CGM convection approach; the study can therefore be considered as a test of its performance in nonradial stability analyses.
引用
收藏
页码:141 / 151
页数:11
相关论文
共 38 条
[1]   Diffusion in helium white dwarf stars [J].
Althaus, LG ;
Benvenuto, OG .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2000, 317 (04) :952-964
[2]   Evolution of helium white dwarfs of low and intermediate masses [J].
Althaus, LG ;
Benvenuto, OG .
ASTROPHYSICAL JOURNAL, 1997, 477 (01) :313-334
[3]   Diffusion and the occurrence of hydrogen-shell flashes in helium white dwarf stars [J].
Althaus, LG ;
Serenelli, AM ;
Benvenuto, OG .
MONTHLY NOTICES OF THE ROYAL ASTRONOMICAL SOCIETY, 2001, 323 (02) :471-483
[4]   Spectroscopic studies of DB white dwarfs: The instability strip of the pulsating DB (V777 HER) stars [J].
Beauchamp, A ;
Wesemael, F ;
Bergeron, P ;
Fontaine, G ;
Saffer, RA ;
Liebert, J ;
Brassard, P .
ASTROPHYSICAL JOURNAL, 1999, 516 (02) :887-891
[5]  
Benvenuto OG, 1998, MON NOT R ASTRON SOC, V293, P177, DOI 10.1046/j.1365-8711.1998.01116.x
[6]  
Bradley P. A., 2000, BALT ASTRON, V9, P485
[7]   AN ASTEROSEISMOLOGICAL DETERMINATION OF THE STRUCTURE OF THE DBV WHITE-DWARF GD-358 [J].
BRADLEY, PA ;
WINGET, DE .
ASTROPHYSICAL JOURNAL, 1994, 430 (02) :850-857
[8]   THE POTENTIAL FOR ASTEROSEISMOLOGY OF DB WHITE-DWARF STARS [J].
BRADLEY, PA ;
WINGET, DE ;
WOOD, MA .
ASTROPHYSICAL JOURNAL, 1993, 406 (02) :661-673
[9]   Theoretical models for asteroseismology of DA white dwarf stars [J].
Bradley, PA .
ASTROPHYSICAL JOURNAL, 1996, 468 (01) :350-368
[10]   ADIABATIC PROPERTIES OF PULSATING DA WHITE-DWARFS .2. MODE TRAPPING IN COMPOSITIONALLY STRATIFIED MODELS [J].
BRASSARD, P ;
FONTAINE, G ;
WESEMAEL, F ;
HANSEN, CJ .
ASTROPHYSICAL JOURNAL SUPPLEMENT SERIES, 1992, 80 (01) :369-401