Measuring the evolutionary rate of cooling of ZZ Ceti

Autores
Córsico, Alejandro Hugo; Romero, Alejandra Daniela
Año de publicación
2013
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 ± 1.4) × 10-15 s s-1 employing the O-C method and (5.45 ± 0.79) × 10-15 s s-1 using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 ± 1.0) × 10-15 s s-1. After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 ± 1.1) × 10-15 s s-1. This value is consistent within uncertainties with the measurement of (4.19 ± 0.73) × 10-15 s s-1 for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.
La lista completa de autores que integran el documento puede consultarse en el archivo.
Facultad de Ciencias Astronómicas y Geofísicas
Materia
Ciencias Astronómicas
stars: evolution
stars: individual (ZZ Ceti, R548)
stars: oscillations (including pulsations)
stars: variables: general
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:10915/85098

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oai_identifier_str oai:sedici.unlp.edu.ar:10915/85098
network_acronym_str SEDICI
repository_id_str 1329
network_name_str SEDICI (UNLP)
spelling Measuring the evolutionary rate of cooling of ZZ CetiCórsico, Alejandro HugoRomero, Alejandra DanielaCiencias Astronómicasstars: evolutionstars: individual (ZZ Ceti, R548)stars: oscillations (including pulsations)stars: variables: generalwhite dwarfsWe have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 ± 1.4) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> employing the O-C method and (5.45 ± 0.79) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 ± 1.0) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 ± 1.1) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. This value is consistent within uncertainties with the measurement of (4.19 ± 0.73) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.La lista completa de autores que integran el documento puede consultarse en el archivo.Facultad de Ciencias Astronómicas y Geofísicas2013info: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/10915/85098enginfo:eu-repo/semantics/altIdentifier/issn/0004-637Xinfo:eu-repo/semantics/altIdentifier/doi/10.1088/0004-637X/771/1/17info: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:UNLP2025-09-29T11:16:30Zoai:sedici.unlp.edu.ar:10915/85098Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:16:30.949SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Measuring the evolutionary rate of cooling of ZZ Ceti
title Measuring the evolutionary rate of cooling of ZZ Ceti
spellingShingle Measuring the evolutionary rate of cooling of ZZ Ceti
Córsico, Alejandro Hugo
Ciencias Astronómicas
stars: evolution
stars: individual (ZZ Ceti, R548)
stars: oscillations (including pulsations)
stars: variables: general
white dwarfs
title_short Measuring the evolutionary rate of cooling of ZZ Ceti
title_full Measuring the evolutionary rate of cooling of ZZ Ceti
title_fullStr Measuring the evolutionary rate of cooling of ZZ Ceti
title_full_unstemmed Measuring the evolutionary rate of cooling of ZZ Ceti
title_sort Measuring the evolutionary rate of cooling of ZZ Ceti
dc.creator.none.fl_str_mv Córsico, Alejandro Hugo
Romero, Alejandra Daniela
author Córsico, Alejandro Hugo
author_facet Córsico, Alejandro Hugo
Romero, Alejandra Daniela
author_role author
author2 Romero, Alejandra Daniela
author2_role author
dc.subject.none.fl_str_mv Ciencias Astronómicas
stars: evolution
stars: individual (ZZ Ceti, R548)
stars: oscillations (including pulsations)
stars: variables: general
white dwarfs
topic Ciencias Astronómicas
stars: evolution
stars: individual (ZZ Ceti, R548)
stars: oscillations (including pulsations)
stars: variables: general
white dwarfs
dc.description.none.fl_txt_mv We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 ± 1.4) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> employing the O-C method and (5.45 ± 0.79) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 ± 1.0) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 ± 1.1) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. This value is consistent within uncertainties with the measurement of (4.19 ± 0.73) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.
La lista completa de autores que integran el documento puede consultarse en el archivo.
Facultad de Ciencias Astronómicas y Geofísicas
description We have finally measured the evolutionary rate of cooling of the pulsating hydrogen atmosphere (DA) white dwarf ZZ Ceti (Ross 548), as reflected by the drift rate of the 213.13260694 s period. Using 41 yr of time-series photometry from 1970 November to 2012 January, we determine the rate of change of this period with time to be dP/dt = (5.2 ± 1.4) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> employing the O-C method and (5.45 ± 0.79) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> using a direct nonlinear least squares fit to the entire lightcurve. We adopt the dP/dt obtained from the nonlinear least squares program as our final determination, but augment the corresponding uncertainty to a more realistic value, ultimately arriving at the measurement of dP/dt = (5.5 ± 1.0) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. After correcting for proper motion, the evolutionary rate of cooling of ZZ Ceti is computed to be (3.3 ± 1.1) × 10<SUP>-15</SUP> s s<SUP>-1</SUP>. This value is consistent within uncertainties with the measurement of (4.19 ± 0.73) × 10<SUP>-15</SUP> s s<SUP>-1</SUP> for another similar pulsating DA white dwarf, G 117-B15A. Measuring the cooling rate of ZZ Ceti helps us refine our stellar structure and evolutionary models, as cooling depends mainly on the core composition and stellar mass. Calibrating white dwarf cooling curves with this measurement will reduce the theoretical uncertainties involved in white dwarf cosmochronometry. Should the 213.13 s period be trapped in the hydrogen envelope, then our determination of its drift rate compared to the expected evolutionary rate suggests an additional source of stellar cooling. Attributing the excess cooling to the emission of axions imposes a constraint on the mass of the hypothetical axion particle.
publishDate 2013
dc.date.none.fl_str_mv 2013
dc.type.none.fl_str_mv info:eu-repo/semantics/article
info:eu-repo/semantics/publishedVersion
Articulo
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format article
status_str publishedVersion
dc.identifier.none.fl_str_mv http://sedici.unlp.edu.ar/handle/10915/85098
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language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0004-637X
info:eu-repo/semantics/altIdentifier/doi/10.1088/0004-637X/771/1/17
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
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