Lithium production in the merging of white dwarf stars

Autores
Longland, R.; Lorén Aguilar, P.; José, J.; García Berro, E.; Althaus, Leandro Gabriel
Año de publicación
2012
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The origin of R Coronae Borealis stars has been elusive for over 200 years. Currently, two theories for their formation have been presented. These are the final flash scenario, in which a dying asymptotic giant branch star throws off its atmosphere to reveal the hydrogen poor, heavily processed material underneath, and the double degenerate scenario, in which two white dwarfs merge to produce a new star with renewed vigour. Some theories predict that the temperatures reached during the latter scenario would destroy any lithium originally present in the white dwarfs. The observed lithium content of some R Coronae Borealis stars, therefore, is often interpreted as an indication that the final flash scenario best describes their formation. In this paper, we show that lithium production can, indeed, occur in the merging of a helium white dwarf with a carbon-oxygen white dwarf if their chemical composition, particularly that of 3He, is fully considered. The production mechanism is described in detail, and the sensitivity of lithium production to the merger environment is investigated. Nucleosynthesis post-processing calculations of smoothed-particle hydrodynamics (SPH) tracer particles are performed to show that any lithium produced in these environments will be concentrated towards the cloud of material surrounding the R CrB star. Measurements of the lithium content of these clouds would, therefore, provide a valuable insight into the formation mechanism of R CrB stars.
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Ciencias Astronómicas
abundances
Nuclear reactions
nucleosynthesis
Stars: abundances
Stars: AGB and post-AGB
Stars: evolution
White dwarfs
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:10915/83974

id SEDICI_a1e8988bed7c86e29c6527c16bb5767b
oai_identifier_str oai:sedici.unlp.edu.ar:10915/83974
network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling Lithium production in the merging of white dwarf starsLongland, R.Lorén Aguilar, P.José, J.García Berro, E.Althaus, Leandro GabrielCiencias AstronómicasabundancesNuclear reactionsnucleosynthesisStars: abundancesStars: AGB and post-AGBStars: evolutionWhite dwarfsThe origin of R Coronae Borealis stars has been elusive for over 200 years. Currently, two theories for their formation have been presented. These are the final flash scenario, in which a dying asymptotic giant branch star throws off its atmosphere to reveal the hydrogen poor, heavily processed material underneath, and the double degenerate scenario, in which two white dwarfs merge to produce a new star with renewed vigour. Some theories predict that the temperatures reached during the latter scenario would destroy any lithium originally present in the white dwarfs. The observed lithium content of some R Coronae Borealis stars, therefore, is often interpreted as an indication that the final flash scenario best describes their formation. In this paper, we show that lithium production can, indeed, occur in the merging of a helium white dwarf with a carbon-oxygen white dwarf if their chemical composition, particularly that of <SUP>3</SUP>He, is fully considered. The production mechanism is described in detail, and the sensitivity of lithium production to the merger environment is investigated. Nucleosynthesis post-processing calculations of smoothed-particle hydrodynamics (SPH) tracer particles are performed to show that any lithium produced in these environments will be concentrated towards the cloud of material surrounding the R CrB star. Measurements of the lithium content of these clouds would, therefore, provide a valuable insight into the formation mechanism of R CrB stars.Facultad de Ciencias Astronómicas y Geofísicas2012info: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/10915/83974enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201219289info: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:UNLP2025-09-29T11:16:01Zoai:sedici.unlp.edu.ar:10915/83974Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:01.684SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Lithium production in the merging of white dwarf stars
title Lithium production in the merging of white dwarf stars
spellingShingle Lithium production in the merging of white dwarf stars
Longland, R.
Ciencias Astronómicas
abundances
Nuclear reactions
nucleosynthesis
Stars: abundances
Stars: AGB and post-AGB
Stars: evolution
White dwarfs
title_short Lithium production in the merging of white dwarf stars
title_full Lithium production in the merging of white dwarf stars
title_fullStr Lithium production in the merging of white dwarf stars
title_full_unstemmed Lithium production in the merging of white dwarf stars
title_sort Lithium production in the merging of white dwarf stars
dc.creator.none.fl_str_mv Longland, R.
Lorén Aguilar, P.
José, J.
García Berro, E.
Althaus, Leandro Gabriel
author Longland, R.
author_facet Longland, R.
Lorén Aguilar, P.
José, J.
García Berro, E.
Althaus, Leandro Gabriel
author_role author
author2 Lorén Aguilar, P.
José, J.
García Berro, E.
Althaus, Leandro Gabriel
author2_role author
author
author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
abundances
Nuclear reactions
nucleosynthesis
Stars: abundances
Stars: AGB and post-AGB
Stars: evolution
White dwarfs
topic Ciencias Astronómicas
abundances
Nuclear reactions
nucleosynthesis
Stars: abundances
Stars: AGB and post-AGB
Stars: evolution
White dwarfs
dc.description.none.fl_txt_mv The origin of R Coronae Borealis stars has been elusive for over 200 years. Currently, two theories for their formation have been presented. These are the final flash scenario, in which a dying asymptotic giant branch star throws off its atmosphere to reveal the hydrogen poor, heavily processed material underneath, and the double degenerate scenario, in which two white dwarfs merge to produce a new star with renewed vigour. Some theories predict that the temperatures reached during the latter scenario would destroy any lithium originally present in the white dwarfs. The observed lithium content of some R Coronae Borealis stars, therefore, is often interpreted as an indication that the final flash scenario best describes their formation. In this paper, we show that lithium production can, indeed, occur in the merging of a helium white dwarf with a carbon-oxygen white dwarf if their chemical composition, particularly that of <SUP>3</SUP>He, is fully considered. The production mechanism is described in detail, and the sensitivity of lithium production to the merger environment is investigated. Nucleosynthesis post-processing calculations of smoothed-particle hydrodynamics (SPH) tracer particles are performed to show that any lithium produced in these environments will be concentrated towards the cloud of material surrounding the R CrB star. Measurements of the lithium content of these clouds would, therefore, provide a valuable insight into the formation mechanism of R CrB stars.
Facultad de Ciencias Astronómicas y Geofísicas
description The origin of R Coronae Borealis stars has been elusive for over 200 years. Currently, two theories for their formation have been presented. These are the final flash scenario, in which a dying asymptotic giant branch star throws off its atmosphere to reveal the hydrogen poor, heavily processed material underneath, and the double degenerate scenario, in which two white dwarfs merge to produce a new star with renewed vigour. Some theories predict that the temperatures reached during the latter scenario would destroy any lithium originally present in the white dwarfs. The observed lithium content of some R Coronae Borealis stars, therefore, is often interpreted as an indication that the final flash scenario best describes their formation. In this paper, we show that lithium production can, indeed, occur in the merging of a helium white dwarf with a carbon-oxygen white dwarf if their chemical composition, particularly that of <SUP>3</SUP>He, is fully considered. The production mechanism is described in detail, and the sensitivity of lithium production to the merger environment is investigated. Nucleosynthesis post-processing calculations of smoothed-particle hydrodynamics (SPH) tracer particles are performed to show that any lithium produced in these environments will be concentrated towards the cloud of material surrounding the R CrB star. Measurements of the lithium content of these clouds would, therefore, provide a valuable insight into the formation mechanism of R CrB stars.
publishDate 2012
dc.date.none.fl_str_mv 2012
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/10915/83974
url http://sedici.unlp.edu.ar/handle/10915/83974
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/10.1051/0004-6361/201219289
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)
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_ 1844616032798375936
score 13.070432