Stratification and isotope separation in CP stars

Autores
Cowley, C. R.; Hubrig, S.; Gonzalez, Jorge Federico
Año de publicación
2009
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We investigate the elemental and isotopic stratification in the atmospheres of selected chemically peculiar (CP) stars of the upper main sequence. Reconfiguration of the UV-Visual Echelle Spectrograph in 2004 has made it possible to examine all three lines of the CaII infrared (IR) triplet. Much of the material analysed was obtained in 2008. We support the claim of Ryabchikova, Kochukhov & Bagnulo (RKB) that the calcium isotopes have distinct stratification profiles for the stars 10 Aql, HR 1217 and HD 122970, with the heavy isotope concentrated towards the higher layers. Better observations are needed to learn the extent to which 40Ca dominates in the deepest layers of all or most CP stars that show the presence of 48Ca. There is little evidence for 40Ca in the spectra of some HgMn stars, and the infrared (IR) triplet in the magnetic star HD 101065 is well fit by pure 48Ca. In HR 5623 (HD 133792) and HD 217522, it is likely that the heavy isotope dominates, though models are possible where this is not the case. While elemental stratification is surely needed in many cases, we point out the importance of including adjustments in the assumed Teff and log(g) values, in attempts to model stratification. We recommend emphasis on profiles of the strongest lines, where the influence of stratification is most evident. Isotopic mixtures, involving the four stable calcium nuclides with masses between 40 and 48 are plausible, but are not emphasized.
Fil: Cowley, C. R.. University of Michigan; Estados Unidos
Fil: Hubrig, S.. European Southern Observatory Chile; Chile
Fil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina
Materia
CHEMICALLY PECULIAR STARS
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:11336/148194
Acceder
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oai_identifier_str oai:ri.conicet.gov.ar:11336/148194
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network_name_str CONICET Digital (CONICET)
spelling Stratification and isotope separation in CP starsCowley, C. R.Hubrig, S.Gonzalez, Jorge FedericoCHEMICALLY PECULIAR STARShttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1We investigate the elemental and isotopic stratification in the atmospheres of selected chemically peculiar (CP) stars of the upper main sequence. Reconfiguration of the UV-Visual Echelle Spectrograph in 2004 has made it possible to examine all three lines of the CaII infrared (IR) triplet. Much of the material analysed was obtained in 2008. We support the claim of Ryabchikova, Kochukhov & Bagnulo (RKB) that the calcium isotopes have distinct stratification profiles for the stars 10 Aql, HR 1217 and HD 122970, with the heavy isotope concentrated towards the higher layers. Better observations are needed to learn the extent to which 40Ca dominates in the deepest layers of all or most CP stars that show the presence of 48Ca. There is little evidence for 40Ca in the spectra of some HgMn stars, and the infrared (IR) triplet in the magnetic star HD 101065 is well fit by pure 48Ca. In HR 5623 (HD 133792) and HD 217522, it is likely that the heavy isotope dominates, though models are possible where this is not the case. While elemental stratification is surely needed in many cases, we point out the importance of including adjustments in the assumed Teff and log(g) values, in attempts to model stratification. We recommend emphasis on profiles of the strongest lines, where the influence of stratification is most evident. Isotopic mixtures, involving the four stable calcium nuclides with masses between 40 and 48 are plausible, but are not emphasized.Fil: Cowley, C. R.. University of Michigan; Estados UnidosFil: Hubrig, S.. European Southern Observatory Chile; ChileFil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaOxford University Press2009-06-03info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/148194Cowley, C. R.; Hubrig, S.; Gonzalez, Jorge Federico; Stratification and isotope separation in CP stars; Oxford University Press; Monthly Notices of the Royal Astronomical Society; 396; 1; 3-6-2009; 485-4990035-8711CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1111/j.1365-2966.2009.14723.xinfo:eu-repo/semantics/altIdentifier/url/https://academic.oup.com/mnras/article/396/1/485/1246956info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:00:46Zoai:ri.conicet.gov.ar:11336/148194instacron: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 10:00:47.122CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Stratification and isotope separation in CP stars
title Stratification and isotope separation in CP stars
spellingShingle Stratification and isotope separation in CP stars
Cowley, C. R.
CHEMICALLY PECULIAR STARS
title_short Stratification and isotope separation in CP stars
title_full Stratification and isotope separation in CP stars
title_fullStr Stratification and isotope separation in CP stars
title_full_unstemmed Stratification and isotope separation in CP stars
title_sort Stratification and isotope separation in CP stars
dc.creator.none.fl_str_mv Cowley, C. R.
Hubrig, S.
Gonzalez, Jorge Federico
author Cowley, C. R.
author_facet Cowley, C. R.
Hubrig, S.
Gonzalez, Jorge Federico
author_role author
author2 Hubrig, S.
Gonzalez, Jorge Federico
author2_role author
author
dc.subject.none.fl_str_mv CHEMICALLY PECULIAR STARS
topic CHEMICALLY PECULIAR STARS
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv We investigate the elemental and isotopic stratification in the atmospheres of selected chemically peculiar (CP) stars of the upper main sequence. Reconfiguration of the UV-Visual Echelle Spectrograph in 2004 has made it possible to examine all three lines of the CaII infrared (IR) triplet. Much of the material analysed was obtained in 2008. We support the claim of Ryabchikova, Kochukhov & Bagnulo (RKB) that the calcium isotopes have distinct stratification profiles for the stars 10 Aql, HR 1217 and HD 122970, with the heavy isotope concentrated towards the higher layers. Better observations are needed to learn the extent to which 40Ca dominates in the deepest layers of all or most CP stars that show the presence of 48Ca. There is little evidence for 40Ca in the spectra of some HgMn stars, and the infrared (IR) triplet in the magnetic star HD 101065 is well fit by pure 48Ca. In HR 5623 (HD 133792) and HD 217522, it is likely that the heavy isotope dominates, though models are possible where this is not the case. While elemental stratification is surely needed in many cases, we point out the importance of including adjustments in the assumed Teff and log(g) values, in attempts to model stratification. We recommend emphasis on profiles of the strongest lines, where the influence of stratification is most evident. Isotopic mixtures, involving the four stable calcium nuclides with masses between 40 and 48 are plausible, but are not emphasized.
Fil: Cowley, C. R.. University of Michigan; Estados Unidos
Fil: Hubrig, S.. European Southern Observatory Chile; Chile
Fil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina
description We investigate the elemental and isotopic stratification in the atmospheres of selected chemically peculiar (CP) stars of the upper main sequence. Reconfiguration of the UV-Visual Echelle Spectrograph in 2004 has made it possible to examine all three lines of the CaII infrared (IR) triplet. Much of the material analysed was obtained in 2008. We support the claim of Ryabchikova, Kochukhov & Bagnulo (RKB) that the calcium isotopes have distinct stratification profiles for the stars 10 Aql, HR 1217 and HD 122970, with the heavy isotope concentrated towards the higher layers. Better observations are needed to learn the extent to which 40Ca dominates in the deepest layers of all or most CP stars that show the presence of 48Ca. There is little evidence for 40Ca in the spectra of some HgMn stars, and the infrared (IR) triplet in the magnetic star HD 101065 is well fit by pure 48Ca. In HR 5623 (HD 133792) and HD 217522, it is likely that the heavy isotope dominates, though models are possible where this is not the case. While elemental stratification is surely needed in many cases, we point out the importance of including adjustments in the assumed Teff and log(g) values, in attempts to model stratification. We recommend emphasis on profiles of the strongest lines, where the influence of stratification is most evident. Isotopic mixtures, involving the four stable calcium nuclides with masses between 40 and 48 are plausible, but are not emphasized.
publishDate 2009
dc.date.none.fl_str_mv 2009-06-03
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/11336/148194
Cowley, C. R.; Hubrig, S.; Gonzalez, Jorge Federico; Stratification and isotope separation in CP stars; Oxford University Press; Monthly Notices of the Royal Astronomical Society; 396; 1; 3-6-2009; 485-499
0035-8711
CONICET Digital
CONICET
url http://hdl.handle.net/11336/148194
identifier_str_mv Cowley, C. R.; Hubrig, S.; Gonzalez, Jorge Federico; Stratification and isotope separation in CP stars; Oxford University Press; Monthly Notices of the Royal Astronomical Society; 396; 1; 3-6-2009; 485-499
0035-8711
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1111/j.1365-2966.2009.14723.x
info:eu-repo/semantics/altIdentifier/url/https://academic.oup.com/mnras/article/396/1/485/1246956
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
dc.publisher.none.fl_str_mv Oxford University Press
publisher.none.fl_str_mv Oxford University Press
dc.source.none.fl_str_mv reponame:CONICET Digital (CONICET)
instname:Consejo Nacional de Investigaciones Científicas y Técnicas
reponame_str CONICET Digital (CONICET)
collection CONICET Digital (CONICET)
instname_str Consejo Nacional de Investigaciones Científicas y Técnicas
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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score 13.070432

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