Gravitational settling of 22Ne and white dwarf evolution
- Autores
- García Berro, E.; Althaus, Leandro Gabriel; Córsico, Alejandro Hugo; Isern, J.
- Año de publicación
- 2008
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- We study the effects of the sedimentation of the trace element 22Ne in the cooling of white dwarfs. In contrast with previous studies - which adopted a simplified treatment of the effects of 22Ne sedimentation - this is done self-consistently for the first time, using an up-to-date stellar evolutionary code in which the diffusion equation is coupled with the full set of equations of stellar evolution. Due the large neutron excess of 22Ne, this isotope rapidly sediments in the interior of the white dwarf. Although we explore a wide range of parameters, we find that when using the most reasonable assumptions concerning the diffusion coefficient and the physical state of the white dwarf interior, the delay introduced by the ensuing chemical differentiation is minor for a typical 0.6 M⊙ white dwarf. For more massive white dwarfs, say MWD ∼1.0 M ⊙, the delay turns out to be considerably larger. These results are in qualitatively good accord with those obtained in previous studies, but we find that the magnitude of the delay introduced by 22Ne sedimentation was underestimated by a factor of ∼2. We also perform a preliminary study of the impact of 22Ne sedimentation on the white dwarf luminosity function. Finally, we hypothesize on the possibility of detecting the sedimentation of 22Ne using pulsating white dwarfs in the appropriate effective temperature range with accurately determined rates of change of the observed periods.
Facultad de Ciencias Astronómicas y Geofísicas - Materia
-
Ciencias Astronómicas
Dense matter
Diffusion
Stars: abundances
Stars: evolution
Stars: interiors
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:10915/84174
Ver los metadatos del registro completo
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Gravitational settling of 22Ne and white dwarf evolutionGarcía Berro, E.Althaus, Leandro GabrielCórsico, Alejandro HugoIsern, J.Ciencias AstronómicasDense matterDiffusionStars: abundancesStars: evolutionStars: interiorsWhite dwarfsWe study the effects of the sedimentation of the trace element <SUP>22</SUP>Ne in the cooling of white dwarfs. In contrast with previous studies - which adopted a simplified treatment of the effects of <SUP>22</SUP>Ne sedimentation - this is done self-consistently for the first time, using an up-to-date stellar evolutionary code in which the diffusion equation is coupled with the full set of equations of stellar evolution. Due the large neutron excess of <SUP>22</SUP>Ne, this isotope rapidly sediments in the interior of the white dwarf. Although we explore a wide range of parameters, we find that when using the most reasonable assumptions concerning the diffusion coefficient and the physical state of the white dwarf interior, the delay introduced by the ensuing chemical differentiation is minor for a typical 0.6 M⊙ white dwarf. For more massive white dwarfs, say M<SUB>WD</SUB> ∼1.0 M ⊙, the delay turns out to be considerably larger. These results are in qualitatively good accord with those obtained in previous studies, but we find that the magnitude of the delay introduced by <SUP>22</SUP>Ne sedimentation was underestimated by a factor of ∼2. We also perform a preliminary study of the impact of <SUP>22</SUP>Ne sedimentation on the white dwarf luminosity function. Finally, we hypothesize on the possibility of detecting the sedimentation of <SUP>22</SUP>Ne using pulsating white dwarfs in the appropriate effective temperature range with accurately determined rates of change of the observed periods.Facultad de Ciencias Astronómicas y Geofísicas2008info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf473-482http://sedici.unlp.edu.ar/handle/10915/84174enginfo:eu-repo/semantics/altIdentifier/issn/0004-637Xinfo:eu-repo/semantics/altIdentifier/doi/10.1086/527536info: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:UNLP2025-09-29T11:16:14Zoai:sedici.unlp.edu.ar:10915/84174Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:15.17SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Gravitational settling of 22Ne and white dwarf evolution |
title |
Gravitational settling of 22Ne and white dwarf evolution |
spellingShingle |
Gravitational settling of 22Ne and white dwarf evolution García Berro, E. Ciencias Astronómicas Dense matter Diffusion Stars: abundances Stars: evolution Stars: interiors White dwarfs |
title_short |
Gravitational settling of 22Ne and white dwarf evolution |
title_full |
Gravitational settling of 22Ne and white dwarf evolution |
title_fullStr |
Gravitational settling of 22Ne and white dwarf evolution |
title_full_unstemmed |
Gravitational settling of 22Ne and white dwarf evolution |
title_sort |
Gravitational settling of 22Ne and white dwarf evolution |
dc.creator.none.fl_str_mv |
García Berro, E. Althaus, Leandro Gabriel Córsico, Alejandro Hugo Isern, J. |
author |
García Berro, E. |
author_facet |
García Berro, E. Althaus, Leandro Gabriel Córsico, Alejandro Hugo Isern, J. |
author_role |
author |
author2 |
Althaus, Leandro Gabriel Córsico, Alejandro Hugo Isern, J. |
author2_role |
author author author |
dc.subject.none.fl_str_mv |
Ciencias Astronómicas Dense matter Diffusion Stars: abundances Stars: evolution Stars: interiors White dwarfs |
topic |
Ciencias Astronómicas Dense matter Diffusion Stars: abundances Stars: evolution Stars: interiors White dwarfs |
dc.description.none.fl_txt_mv |
We study the effects of the sedimentation of the trace element <SUP>22</SUP>Ne in the cooling of white dwarfs. In contrast with previous studies - which adopted a simplified treatment of the effects of <SUP>22</SUP>Ne sedimentation - this is done self-consistently for the first time, using an up-to-date stellar evolutionary code in which the diffusion equation is coupled with the full set of equations of stellar evolution. Due the large neutron excess of <SUP>22</SUP>Ne, this isotope rapidly sediments in the interior of the white dwarf. Although we explore a wide range of parameters, we find that when using the most reasonable assumptions concerning the diffusion coefficient and the physical state of the white dwarf interior, the delay introduced by the ensuing chemical differentiation is minor for a typical 0.6 M⊙ white dwarf. For more massive white dwarfs, say M<SUB>WD</SUB> ∼1.0 M ⊙, the delay turns out to be considerably larger. These results are in qualitatively good accord with those obtained in previous studies, but we find that the magnitude of the delay introduced by <SUP>22</SUP>Ne sedimentation was underestimated by a factor of ∼2. We also perform a preliminary study of the impact of <SUP>22</SUP>Ne sedimentation on the white dwarf luminosity function. Finally, we hypothesize on the possibility of detecting the sedimentation of <SUP>22</SUP>Ne using pulsating white dwarfs in the appropriate effective temperature range with accurately determined rates of change of the observed periods. Facultad de Ciencias Astronómicas y Geofísicas |
description |
We study the effects of the sedimentation of the trace element <SUP>22</SUP>Ne in the cooling of white dwarfs. In contrast with previous studies - which adopted a simplified treatment of the effects of <SUP>22</SUP>Ne sedimentation - this is done self-consistently for the first time, using an up-to-date stellar evolutionary code in which the diffusion equation is coupled with the full set of equations of stellar evolution. Due the large neutron excess of <SUP>22</SUP>Ne, this isotope rapidly sediments in the interior of the white dwarf. Although we explore a wide range of parameters, we find that when using the most reasonable assumptions concerning the diffusion coefficient and the physical state of the white dwarf interior, the delay introduced by the ensuing chemical differentiation is minor for a typical 0.6 M⊙ white dwarf. For more massive white dwarfs, say M<SUB>WD</SUB> ∼1.0 M ⊙, the delay turns out to be considerably larger. These results are in qualitatively good accord with those obtained in previous studies, but we find that the magnitude of the delay introduced by <SUP>22</SUP>Ne sedimentation was underestimated by a factor of ∼2. We also perform a preliminary study of the impact of <SUP>22</SUP>Ne sedimentation on the white dwarf luminosity function. Finally, we hypothesize on the possibility of detecting the sedimentation of <SUP>22</SUP>Ne using pulsating white dwarfs in the appropriate effective temperature range with accurately determined rates of change of the observed periods. |
publishDate |
2008 |
dc.date.none.fl_str_mv |
2008 |
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/10915/84174 |
url |
http://sedici.unlp.edu.ar/handle/10915/84174 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/0004-637X info:eu-repo/semantics/altIdentifier/doi/10.1086/527536 |
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) |
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openAccess |
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http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
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