Fingering convection in red giants revisited

Autores
Wachlin, Felipe Carlos; Vauclair, S.; Althaus, Leandro Gabriel
Año de publicación
2014
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Context. Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in red giant stars; it is due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning zone. Recent studies show, however, that this mixing is not sufficient to account for the needed surface abundances. Aims. A new prescription for fingering convection, based on 3D numerical simulations has recently been proposed. The resulting mixing coefficient is larger than those previously given in the literature. We compute models using this new coefficient and compare them to previous studies. Methods. We used the LPCODE stellar evolution code with a generalized version of the mixing length theory to compute red giant models and we introduce fingering convection using the BGS prescription. Results. The results show that, although the fingering zone now reaches the outer dynamical convective zone, the efficiency of the mixing is not enough to account for the observations. The fingering mixing coefficient should be increased by two orders of magnitude for the needed surface abundances to be reached. Conclusions. We confirm that fingering convection cannot be the mixing process needed to account for surface abundances in red giant branch stars.
Instituto de Astrofísica de La Plata
Materia
Ciencias Astronómicas
Instabilities
Stars: abundances
Stars: evolution
Stars: interiors
Nivel de accesibilidad
acceso abierto
Condiciones de uso
http://creativecommons.org/licenses/by-nc-sa/4.0/
Repositorio
SEDICI (UNLP)
Institución
Universidad Nacional de La Plata
OAI Identificador
oai:sedici.unlp.edu.ar:10915/84833

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network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling Fingering convection in red giants revisitedWachlin, Felipe CarlosVauclair, S.Althaus, Leandro GabrielCiencias AstronómicasInstabilitiesStars: abundancesStars: evolutionStars: interiorsContext. Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in red giant stars; it is due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning zone. Recent studies show, however, that this mixing is not sufficient to account for the needed surface abundances. Aims. A new prescription for fingering convection, based on 3D numerical simulations has recently been proposed. The resulting mixing coefficient is larger than those previously given in the literature. We compute models using this new coefficient and compare them to previous studies. Methods. We used the LPCODE stellar evolution code with a generalized version of the mixing length theory to compute red giant models and we introduce fingering convection using the BGS prescription. Results. The results show that, although the fingering zone now reaches the outer dynamical convective zone, the efficiency of the mixing is not enough to account for the observations. The fingering mixing coefficient should be increased by two orders of magnitude for the needed surface abundances to be reached. Conclusions. We confirm that fingering convection cannot be the mixing process needed to account for surface abundances in red giant branch stars.Instituto de Astrofísica de La Plata2014info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfhttp://sedici.unlp.edu.ar/handle/10915/84833enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201424580info: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:UNLP2025-09-29T11:16:20Zoai:sedici.unlp.edu.ar:10915/84833Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:21.142SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Fingering convection in red giants revisited
title Fingering convection in red giants revisited
spellingShingle Fingering convection in red giants revisited
Wachlin, Felipe Carlos
Ciencias Astronómicas
Instabilities
Stars: abundances
Stars: evolution
Stars: interiors
title_short Fingering convection in red giants revisited
title_full Fingering convection in red giants revisited
title_fullStr Fingering convection in red giants revisited
title_full_unstemmed Fingering convection in red giants revisited
title_sort Fingering convection in red giants revisited
dc.creator.none.fl_str_mv Wachlin, Felipe Carlos
Vauclair, S.
Althaus, Leandro Gabriel
author Wachlin, Felipe Carlos
author_facet Wachlin, Felipe Carlos
Vauclair, S.
Althaus, Leandro Gabriel
author_role author
author2 Vauclair, S.
Althaus, Leandro Gabriel
author2_role author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
Instabilities
Stars: abundances
Stars: evolution
Stars: interiors
topic Ciencias Astronómicas
Instabilities
Stars: abundances
Stars: evolution
Stars: interiors
dc.description.none.fl_txt_mv Context. Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in red giant stars; it is due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning zone. Recent studies show, however, that this mixing is not sufficient to account for the needed surface abundances. Aims. A new prescription for fingering convection, based on 3D numerical simulations has recently been proposed. The resulting mixing coefficient is larger than those previously given in the literature. We compute models using this new coefficient and compare them to previous studies. Methods. We used the LPCODE stellar evolution code with a generalized version of the mixing length theory to compute red giant models and we introduce fingering convection using the BGS prescription. Results. The results show that, although the fingering zone now reaches the outer dynamical convective zone, the efficiency of the mixing is not enough to account for the observations. The fingering mixing coefficient should be increased by two orders of magnitude for the needed surface abundances to be reached. Conclusions. We confirm that fingering convection cannot be the mixing process needed to account for surface abundances in red giant branch stars.
Instituto de Astrofísica de La Plata
description Context. Fingering (thermohaline) convection has been invoked for several years as a possible extra-mixing which could occur in red giant stars; it is due to the modification of the chemical composition induced by nuclear reactions in the hydrogen burning zone. Recent studies show, however, that this mixing is not sufficient to account for the needed surface abundances. Aims. A new prescription for fingering convection, based on 3D numerical simulations has recently been proposed. The resulting mixing coefficient is larger than those previously given in the literature. We compute models using this new coefficient and compare them to previous studies. Methods. We used the LPCODE stellar evolution code with a generalized version of the mixing length theory to compute red giant models and we introduce fingering convection using the BGS prescription. Results. The results show that, although the fingering zone now reaches the outer dynamical convective zone, the efficiency of the mixing is not enough to account for the observations. The fingering mixing coefficient should be increased by two orders of magnitude for the needed surface abundances to be reached. Conclusions. We confirm that fingering convection cannot be the mixing process needed to account for surface abundances in red giant branch stars.
publishDate 2014
dc.date.none.fl_str_mv 2014
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/10915/84833
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dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0004-6361
info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201424580
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
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
reponame_str SEDICI (UNLP)
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instname_str Universidad Nacional de La Plata
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institution UNLP
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
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