New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution

Autores
Althaus, Leandro Gabriel; García Berro, Enrique; Isern, Jordi; Corsico, Alejandro Hugo; Miller Bertolami, Marcelo Miguel
Año de publicación
2012
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Context. Cool white dwarfs are reliable and independent stellar chronometers. The most common white dwarfs have carbon-oxygen dense cores. Consequently, the cooling ages of very cool white dwarfs sensitively depend on the adopted phase diagram of the carbon-oxygen binary mixture. Aims: A new phase diagram of dense carbon-oxygen mixtures appropriate for white dwarf interiors has been recently obtained using direct molecular dynamics simulations. In this paper, we explore the consequences of this phase diagram in the evolution of cool white dwarfs. Methods: To do this we employ a detailed stellar evolutionary code and accurate initial white dwarf configurations, derived from the full evolution of progenitor stars. We use two different phase diagrams, that of Horowitz et al. (2010, Phys. Rev. Lett., 104, 231101), which presents an azeotrope, and the phase diagram of Segretain & Chabrier (1993, A&A, 271, L13), which is of the spindle form. Results: We computed the evolution of 0.593 and 0.878 Msun white dwarf models during the crystallization phase, and we found that the energy released by carbon-oxygen phase separation is smaller when the new phase diagram of Horowitz et al. is used. This translates into time delays that are on average a factor ~2 smaller than those obtained when the phase diagram of Segretain & Chabrier is employed. Conclusions: Our results have important implications for white dwarf cosmochronology, because the cooling ages of very old white dwarfs are different for the two phase diagrams. This may have a noticeable impact on the age determinations of very old globular clusters, for which the white dwarf color-magnitude diagram provides an independent way of estimating their age.
Fil: Althaus, Leandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: García Berro, Enrique. Institute for Space Studies of Catalonia; España
Fil: Isern, Jordi. Institute for Space Studies of Catalonia; España
Fil: Corsico, Alejandro Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: Miller Bertolami, Marcelo Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina
Materia
STARS: EVOLUTION
WHITE DWARFS
STARS: INTERIORS
Nivel de accesibilidad
acceso abierto
Condiciones de uso
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
Repositorio
CONICET Digital (CONICET)
Institución
Consejo Nacional de Investigaciones Científicas y Técnicas
OAI Identificador
oai:ri.conicet.gov.ar:11336/82519

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network_name_str CONICET Digital (CONICET)
spelling New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolutionAlthaus, Leandro GabrielGarcía Berro, EnriqueIsern, JordiCorsico, Alejandro HugoMiller Bertolami, Marcelo MiguelSTARS: EVOLUTIONWHITE DWARFSSTARS: INTERIORShttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1Context. Cool white dwarfs are reliable and independent stellar chronometers. The most common white dwarfs have carbon-oxygen dense cores. Consequently, the cooling ages of very cool white dwarfs sensitively depend on the adopted phase diagram of the carbon-oxygen binary mixture. Aims: A new phase diagram of dense carbon-oxygen mixtures appropriate for white dwarf interiors has been recently obtained using direct molecular dynamics simulations. In this paper, we explore the consequences of this phase diagram in the evolution of cool white dwarfs. Methods: To do this we employ a detailed stellar evolutionary code and accurate initial white dwarf configurations, derived from the full evolution of progenitor stars. We use two different phase diagrams, that of Horowitz et al. (2010, Phys. Rev. Lett., 104, 231101), which presents an azeotrope, and the phase diagram of Segretain & Chabrier (1993, A&A, 271, L13), which is of the spindle form. Results: We computed the evolution of 0.593 and 0.878 Msun white dwarf models during the crystallization phase, and we found that the energy released by carbon-oxygen phase separation is smaller when the new phase diagram of Horowitz et al. is used. This translates into time delays that are on average a factor ~2 smaller than those obtained when the phase diagram of Segretain & Chabrier is employed. Conclusions: Our results have important implications for white dwarf cosmochronology, because the cooling ages of very old white dwarfs are different for the two phase diagrams. This may have a noticeable impact on the age determinations of very old globular clusters, for which the white dwarf color-magnitude diagram provides an independent way of estimating their age.Fil: Althaus, Leandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: García Berro, Enrique. Institute for Space Studies of Catalonia; EspañaFil: Isern, Jordi. Institute for Space Studies of Catalonia; EspañaFil: Corsico, Alejandro Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Miller Bertolami, Marcelo Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaEDP Sciences2012-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/82519Althaus, Leandro Gabriel; García Berro, Enrique; Isern, Jordi; Corsico, Alejandro Hugo; Miller Bertolami, Marcelo Miguel; New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution; EDP Sciences; Astronomy and Astrophysics; 537; 1-2012; 33-430004-6361CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201117902info:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/articles/aa/abs/2012/01/aa17902-11/aa17902-11.htmlinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:03:01Zoai:ri.conicet.gov.ar:11336/82519instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 10:03:01.933CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
title New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
spellingShingle New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
Althaus, Leandro Gabriel
STARS: EVOLUTION
WHITE DWARFS
STARS: INTERIORS
title_short New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
title_full New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
title_fullStr New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
title_full_unstemmed New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
title_sort New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution
dc.creator.none.fl_str_mv Althaus, Leandro Gabriel
García Berro, Enrique
Isern, Jordi
Corsico, Alejandro Hugo
Miller Bertolami, Marcelo Miguel
author Althaus, Leandro Gabriel
author_facet Althaus, Leandro Gabriel
García Berro, Enrique
Isern, Jordi
Corsico, Alejandro Hugo
Miller Bertolami, Marcelo Miguel
author_role author
author2 García Berro, Enrique
Isern, Jordi
Corsico, Alejandro Hugo
Miller Bertolami, Marcelo Miguel
author2_role author
author
author
author
dc.subject.none.fl_str_mv STARS: EVOLUTION
WHITE DWARFS
STARS: INTERIORS
topic STARS: EVOLUTION
WHITE DWARFS
STARS: INTERIORS
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv Context. Cool white dwarfs are reliable and independent stellar chronometers. The most common white dwarfs have carbon-oxygen dense cores. Consequently, the cooling ages of very cool white dwarfs sensitively depend on the adopted phase diagram of the carbon-oxygen binary mixture. Aims: A new phase diagram of dense carbon-oxygen mixtures appropriate for white dwarf interiors has been recently obtained using direct molecular dynamics simulations. In this paper, we explore the consequences of this phase diagram in the evolution of cool white dwarfs. Methods: To do this we employ a detailed stellar evolutionary code and accurate initial white dwarf configurations, derived from the full evolution of progenitor stars. We use two different phase diagrams, that of Horowitz et al. (2010, Phys. Rev. Lett., 104, 231101), which presents an azeotrope, and the phase diagram of Segretain & Chabrier (1993, A&A, 271, L13), which is of the spindle form. Results: We computed the evolution of 0.593 and 0.878 Msun white dwarf models during the crystallization phase, and we found that the energy released by carbon-oxygen phase separation is smaller when the new phase diagram of Horowitz et al. is used. This translates into time delays that are on average a factor ~2 smaller than those obtained when the phase diagram of Segretain & Chabrier is employed. Conclusions: Our results have important implications for white dwarf cosmochronology, because the cooling ages of very old white dwarfs are different for the two phase diagrams. This may have a noticeable impact on the age determinations of very old globular clusters, for which the white dwarf color-magnitude diagram provides an independent way of estimating their age.
Fil: Althaus, Leandro Gabriel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: García Berro, Enrique. Institute for Space Studies of Catalonia; España
Fil: Isern, Jordi. Institute for Space Studies of Catalonia; España
Fil: Corsico, Alejandro Hugo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: Miller Bertolami, Marcelo Miguel. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina
description Context. Cool white dwarfs are reliable and independent stellar chronometers. The most common white dwarfs have carbon-oxygen dense cores. Consequently, the cooling ages of very cool white dwarfs sensitively depend on the adopted phase diagram of the carbon-oxygen binary mixture. Aims: A new phase diagram of dense carbon-oxygen mixtures appropriate for white dwarf interiors has been recently obtained using direct molecular dynamics simulations. In this paper, we explore the consequences of this phase diagram in the evolution of cool white dwarfs. Methods: To do this we employ a detailed stellar evolutionary code and accurate initial white dwarf configurations, derived from the full evolution of progenitor stars. We use two different phase diagrams, that of Horowitz et al. (2010, Phys. Rev. Lett., 104, 231101), which presents an azeotrope, and the phase diagram of Segretain & Chabrier (1993, A&A, 271, L13), which is of the spindle form. Results: We computed the evolution of 0.593 and 0.878 Msun white dwarf models during the crystallization phase, and we found that the energy released by carbon-oxygen phase separation is smaller when the new phase diagram of Horowitz et al. is used. This translates into time delays that are on average a factor ~2 smaller than those obtained when the phase diagram of Segretain & Chabrier is employed. Conclusions: Our results have important implications for white dwarf cosmochronology, because the cooling ages of very old white dwarfs are different for the two phase diagrams. This may have a noticeable impact on the age determinations of very old globular clusters, for which the white dwarf color-magnitude diagram provides an independent way of estimating their age.
publishDate 2012
dc.date.none.fl_str_mv 2012-01
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
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://hdl.handle.net/11336/82519
Althaus, Leandro Gabriel; García Berro, Enrique; Isern, Jordi; Corsico, Alejandro Hugo; Miller Bertolami, Marcelo Miguel; New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution; EDP Sciences; Astronomy and Astrophysics; 537; 1-2012; 33-43
0004-6361
CONICET Digital
CONICET
url http://hdl.handle.net/11336/82519
identifier_str_mv Althaus, Leandro Gabriel; García Berro, Enrique; Isern, Jordi; Corsico, Alejandro Hugo; Miller Bertolami, Marcelo Miguel; New phase diagrams for dense carbon-oxygen mixtures and white dwarf evolution; EDP Sciences; Astronomy and Astrophysics; 537; 1-2012; 33-43
0004-6361
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201117902
info:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/articles/aa/abs/2012/01/aa17902-11/aa17902-11.html
dc.rights.none.fl_str_mv info:eu-repo/semantics/openAccess
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
eu_rights_str_mv openAccess
rights_invalid_str_mv https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
dc.format.none.fl_str_mv application/pdf
application/pdf
application/pdf
application/pdf
dc.publisher.none.fl_str_mv EDP Sciences
publisher.none.fl_str_mv EDP Sciences
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
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reponame_str CONICET Digital (CONICET)
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repository.name.fl_str_mv CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas
repository.mail.fl_str_mv dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar
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