Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A
- Autores
- Benvenuto, Omar Gustavo; Córsico, Alejandro Hugo; Althaus, Leandro Gabriel; Serenelli, Aldo Marcelo
- Año de publicación
- 2002
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- We study the structural characteristic of the variable DA white dwarf G117-B15A by applying the methods of asteroseismology. For such a purpose, we construct white dwarf evolutionary models considering a detailed and up-to-date physical description as well as several processes responsible for the occurrence of element diffusion. We have considered several thicknesses for the outermost hydrogen layer, whereas for the inner helium-, carbon- and oxygen-rich layers we considered realistic profiles predicted by calculations of the white dwarf progenitor evolution. The stellar masses we have analysed cover the mass range of 0.50 ≤ M⁎/M⊙ ≤ 0.60. The evolution of each of the considered model sequences was followed down to very low effective temperatures; in particular, from 12 500 K on we computed the dipolar, linear, adiabatic oscillations with radial order k = 1,..., 4. We find that asteroseismological results are not univocal regarding mode identification for the case of G117-B15A. However, our asteroseismological results are compatible with spectroscopic data only if the observed periods of 215.2, 271.0 and 304.4 s are due to dipolar modes with k = 2, 3, 4, respectively. Our calculations indicate that the best fit to the observed period pattern of G117-B15A corresponds to a DA white dwarf structure with a stellar mass of 0.525 M⊙, with a hydrogen mass fraction log(MH/M⁎) ≳ -3.83 at an effective temperature Teff ≈ 11 800 K. The value of the stellar mass is consistent with that obtained spectroscopically by Koester & Allard.
Facultad de Ciencias Astronómicas y Geofísicas - Materia
-
Ciencias Astronómicas
Stars: evolution
Stars: individual: G117-B15A
Stars: interiors
Stars: oscillations
White dwarfs - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-sa/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/84613
Ver los metadatos del registro completo
id |
SEDICI_da9cee31346e5a11cb45585ca15ab33a |
---|---|
oai_identifier_str |
oai:sedici.unlp.edu.ar:10915/84613 |
network_acronym_str |
SEDICI |
repository_id_str |
1329 |
network_name_str |
SEDICI (UNLP) |
spelling |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15ABenvenuto, Omar GustavoCórsico, Alejandro HugoAlthaus, Leandro GabrielSerenelli, Aldo MarceloCiencias AstronómicasStars: evolutionStars: individual: G117-B15AStars: interiorsStars: oscillationsWhite dwarfsWe study the structural characteristic of the variable DA white dwarf G117-B15A by applying the methods of asteroseismology. For such a purpose, we construct white dwarf evolutionary models considering a detailed and up-to-date physical description as well as several processes responsible for the occurrence of element diffusion. We have considered several thicknesses for the outermost hydrogen layer, whereas for the inner helium-, carbon- and oxygen-rich layers we considered realistic profiles predicted by calculations of the white dwarf progenitor evolution. The stellar masses we have analysed cover the mass range of 0.50 ≤ M⁎/M⊙ ≤ 0.60. The evolution of each of the considered model sequences was followed down to very low effective temperatures; in particular, from 12 500 K on we computed the dipolar, linear, adiabatic oscillations with radial order k = 1,..., 4. We find that asteroseismological results are not univocal regarding mode identification for the case of G117-B15A. However, our asteroseismological results are compatible with spectroscopic data only if the observed periods of 215.2, 271.0 and 304.4 s are due to dipolar modes with k = 2, 3, 4, respectively. Our calculations indicate that the best fit to the observed period pattern of G117-B15A corresponds to a DA white dwarf structure with a stellar mass of 0.525 M⊙, with a hydrogen mass fraction log(M<SUB>H</SUB>/M⁎) ≳ -3.83 at an effective temperature T<SUB>eff</SUB> ≈ 11 800 K. The value of the stellar mass is consistent with that obtained spectroscopically by Koester & Allard.Facultad de Ciencias Astronómicas y Geofísicas2002info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf399-408http://sedici.unlp.edu.ar/handle/10915/84613enginfo:eu-repo/semantics/altIdentifier/issn/0035-8711info:eu-repo/semantics/altIdentifier/doi/10.1046/j.1365-8711.2002.05312.xinfo:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-sa/4.0/Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:16:15Zoai:sedici.unlp.edu.ar:10915/84613Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:16.285SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
title |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
spellingShingle |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A Benvenuto, Omar Gustavo Ciencias Astronómicas Stars: evolution Stars: individual: G117-B15A Stars: interiors Stars: oscillations White dwarfs |
title_short |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
title_full |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
title_fullStr |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
title_full_unstemmed |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
title_sort |
Time-dependent diffusion in pulsating white dwarf stars: Asteroseismology of G117-B15A |
dc.creator.none.fl_str_mv |
Benvenuto, Omar Gustavo Córsico, Alejandro Hugo Althaus, Leandro Gabriel Serenelli, Aldo Marcelo |
author |
Benvenuto, Omar Gustavo |
author_facet |
Benvenuto, Omar Gustavo Córsico, Alejandro Hugo Althaus, Leandro Gabriel Serenelli, Aldo Marcelo |
author_role |
author |
author2 |
Córsico, Alejandro Hugo Althaus, Leandro Gabriel Serenelli, Aldo Marcelo |
author2_role |
author author author |
dc.subject.none.fl_str_mv |
Ciencias Astronómicas Stars: evolution Stars: individual: G117-B15A Stars: interiors Stars: oscillations White dwarfs |
topic |
Ciencias Astronómicas Stars: evolution Stars: individual: G117-B15A Stars: interiors Stars: oscillations White dwarfs |
dc.description.none.fl_txt_mv |
We study the structural characteristic of the variable DA white dwarf G117-B15A by applying the methods of asteroseismology. For such a purpose, we construct white dwarf evolutionary models considering a detailed and up-to-date physical description as well as several processes responsible for the occurrence of element diffusion. We have considered several thicknesses for the outermost hydrogen layer, whereas for the inner helium-, carbon- and oxygen-rich layers we considered realistic profiles predicted by calculations of the white dwarf progenitor evolution. The stellar masses we have analysed cover the mass range of 0.50 ≤ M⁎/M⊙ ≤ 0.60. The evolution of each of the considered model sequences was followed down to very low effective temperatures; in particular, from 12 500 K on we computed the dipolar, linear, adiabatic oscillations with radial order k = 1,..., 4. We find that asteroseismological results are not univocal regarding mode identification for the case of G117-B15A. However, our asteroseismological results are compatible with spectroscopic data only if the observed periods of 215.2, 271.0 and 304.4 s are due to dipolar modes with k = 2, 3, 4, respectively. Our calculations indicate that the best fit to the observed period pattern of G117-B15A corresponds to a DA white dwarf structure with a stellar mass of 0.525 M⊙, with a hydrogen mass fraction log(M<SUB>H</SUB>/M⁎) ≳ -3.83 at an effective temperature T<SUB>eff</SUB> ≈ 11 800 K. The value of the stellar mass is consistent with that obtained spectroscopically by Koester & Allard. Facultad de Ciencias Astronómicas y Geofísicas |
description |
We study the structural characteristic of the variable DA white dwarf G117-B15A by applying the methods of asteroseismology. For such a purpose, we construct white dwarf evolutionary models considering a detailed and up-to-date physical description as well as several processes responsible for the occurrence of element diffusion. We have considered several thicknesses for the outermost hydrogen layer, whereas for the inner helium-, carbon- and oxygen-rich layers we considered realistic profiles predicted by calculations of the white dwarf progenitor evolution. The stellar masses we have analysed cover the mass range of 0.50 ≤ M⁎/M⊙ ≤ 0.60. The evolution of each of the considered model sequences was followed down to very low effective temperatures; in particular, from 12 500 K on we computed the dipolar, linear, adiabatic oscillations with radial order k = 1,..., 4. We find that asteroseismological results are not univocal regarding mode identification for the case of G117-B15A. However, our asteroseismological results are compatible with spectroscopic data only if the observed periods of 215.2, 271.0 and 304.4 s are due to dipolar modes with k = 2, 3, 4, respectively. Our calculations indicate that the best fit to the observed period pattern of G117-B15A corresponds to a DA white dwarf structure with a stellar mass of 0.525 M⊙, with a hydrogen mass fraction log(M<SUB>H</SUB>/M⁎) ≳ -3.83 at an effective temperature T<SUB>eff</SUB> ≈ 11 800 K. The value of the stellar mass is consistent with that obtained spectroscopically by Koester & Allard. |
publishDate |
2002 |
dc.date.none.fl_str_mv |
2002 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Articulo http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://sedici.unlp.edu.ar/handle/10915/84613 |
url |
http://sedici.unlp.edu.ar/handle/10915/84613 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/0035-8711 info:eu-repo/semantics/altIdentifier/doi/10.1046/j.1365-8711.2002.05312.x |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
dc.format.none.fl_str_mv |
application/pdf 399-408 |
dc.source.none.fl_str_mv |
reponame:SEDICI (UNLP) instname:Universidad Nacional de La Plata instacron:UNLP |
reponame_str |
SEDICI (UNLP) |
collection |
SEDICI (UNLP) |
instname_str |
Universidad Nacional de La Plata |
instacron_str |
UNLP |
institution |
UNLP |
repository.name.fl_str_mv |
SEDICI (UNLP) - Universidad Nacional de La Plata |
repository.mail.fl_str_mv |
alira@sedici.unlp.edu.ar |
_version_ |
1844616035328589824 |
score |
13.070432 |