ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres
- Autores
- Battich, Tiara; Miller Bertolami, Marcelo Miguel; Córsico, Alejandro Hugo; Althaus, Leandro Gabriel
- Año de publicación
- 2017
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- The ε mechanism is a self-excitation mechanism of stellar pulsations which acts in regions where nuclear burning takes place. It has been shown that the ε mechanism can excite pulsations in hot pre-horizontal branch stars before they settle into the stable helium core-burning phase and that the shortest periods of LS IV-14º116 could be explained that way.We aim to study the ε mechanism in stellar models appropriate for hot pre-horizontal branch stars to predict their pulsational properties.We perform detailed computations of non-adiabatic non-radial pulsations on such stellar models.We predict a new instability domain of long-period gravity modes in the log g−log T eff plane at roughly 22000 K ≲ Te ≲ 50000 K and 4.67 ≲ log g ≲ 6.15, with a period range from ∼ 200 to ∼ 2000 s. Comparison with the three known pulsating He-rich subdwarfs shows that the ε mechanism can excite pulsations in models with similar surface properties except for modes with the shortest observed periods. Based on simple estimates we expect at least 3 stars in the current samples of hot-subdwarf stars to be pulsating by the ε mechanism. Our results could constitute a theoretical basis for future searches of pulsators in the Galactic field.
Facultad de Ciencias Astronómicas y Geofísicas - Materia
-
Ciencias Astronómicas
low-mass stars
stellar oscillations
horizontal-branch stars - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-nd/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/81693
Ver los metadatos del registro completo
id |
SEDICI_15eab37376c946b27ba74c98ca43383a |
---|---|
oai_identifier_str |
oai:sedici.unlp.edu.ar:10915/81693 |
network_acronym_str |
SEDICI |
repository_id_str |
1329 |
network_name_str |
SEDICI (UNLP) |
spelling |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheresBattich, TiaraMiller Bertolami, Marcelo MiguelCórsico, Alejandro HugoAlthaus, Leandro GabrielCiencias Astronómicaslow-mass starsstellar oscillationshorizontal-branch starsThe ε mechanism is a self-excitation mechanism of stellar pulsations which acts in regions where nuclear burning takes place. It has been shown that the ε mechanism can excite pulsations in hot pre-horizontal branch stars before they settle into the stable helium core-burning phase and that the shortest periods of LS IV-14º116 could be explained that way.We aim to study the ε mechanism in stellar models appropriate for hot pre-horizontal branch stars to predict their pulsational properties.We perform detailed computations of non-adiabatic non-radial pulsations on such stellar models.We predict a new instability domain of long-period gravity modes in the log g−log T eff plane at roughly 22000 K ≲ Te ≲ 50000 K and 4.67 ≲ log g ≲ 6.15, with a period range from ∼ 200 to ∼ 2000 s. Comparison with the three known pulsating He-rich subdwarfs shows that the ε mechanism can excite pulsations in models with similar surface properties except for modes with the shortest observed periods. Based on simple estimates we expect at least 3 stars in the current samples of hot-subdwarf stars to be pulsating by the ε mechanism. Our results could constitute a theoretical basis for future searches of pulsators in the Galactic field.Facultad de Ciencias Astronómicas y Geofísicas2017info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf152-159http://sedici.unlp.edu.ar/handle/10915/81693enginfo:eu-repo/semantics/altIdentifier/issn/2543-6376info:eu-repo/semantics/altIdentifier/doi/10.1515/astro-2017-0431info:eu-repo/semantics/openAccesshttp://creativecommons.org/licenses/by-nc-nd/4.0/Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0)reponame:SEDICI (UNLP)instname:Universidad Nacional de La Platainstacron:UNLP2025-09-29T11:15:12Zoai:sedici.unlp.edu.ar:10915/81693Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:15:12.695SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
title |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
spellingShingle |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres Battich, Tiara Ciencias Astronómicas low-mass stars stellar oscillations horizontal-branch stars |
title_short |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
title_full |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
title_fullStr |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
title_full_unstemmed |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
title_sort |
ε-mechanism driven pulsations in hot subdwarf stars with mixed H-He atmospheres |
dc.creator.none.fl_str_mv |
Battich, Tiara Miller Bertolami, Marcelo Miguel Córsico, Alejandro Hugo Althaus, Leandro Gabriel |
author |
Battich, Tiara |
author_facet |
Battich, Tiara Miller Bertolami, Marcelo Miguel Córsico, Alejandro Hugo Althaus, Leandro Gabriel |
author_role |
author |
author2 |
Miller Bertolami, Marcelo Miguel Córsico, Alejandro Hugo Althaus, Leandro Gabriel |
author2_role |
author author author |
dc.subject.none.fl_str_mv |
Ciencias Astronómicas low-mass stars stellar oscillations horizontal-branch stars |
topic |
Ciencias Astronómicas low-mass stars stellar oscillations horizontal-branch stars |
dc.description.none.fl_txt_mv |
The ε mechanism is a self-excitation mechanism of stellar pulsations which acts in regions where nuclear burning takes place. It has been shown that the ε mechanism can excite pulsations in hot pre-horizontal branch stars before they settle into the stable helium core-burning phase and that the shortest periods of LS IV-14º116 could be explained that way.We aim to study the ε mechanism in stellar models appropriate for hot pre-horizontal branch stars to predict their pulsational properties.We perform detailed computations of non-adiabatic non-radial pulsations on such stellar models.We predict a new instability domain of long-period gravity modes in the log g−log T eff plane at roughly 22000 K ≲ Te ≲ 50000 K and 4.67 ≲ log g ≲ 6.15, with a period range from ∼ 200 to ∼ 2000 s. Comparison with the three known pulsating He-rich subdwarfs shows that the ε mechanism can excite pulsations in models with similar surface properties except for modes with the shortest observed periods. Based on simple estimates we expect at least 3 stars in the current samples of hot-subdwarf stars to be pulsating by the ε mechanism. Our results could constitute a theoretical basis for future searches of pulsators in the Galactic field. Facultad de Ciencias Astronómicas y Geofísicas |
description |
The ε mechanism is a self-excitation mechanism of stellar pulsations which acts in regions where nuclear burning takes place. It has been shown that the ε mechanism can excite pulsations in hot pre-horizontal branch stars before they settle into the stable helium core-burning phase and that the shortest periods of LS IV-14º116 could be explained that way.We aim to study the ε mechanism in stellar models appropriate for hot pre-horizontal branch stars to predict their pulsational properties.We perform detailed computations of non-adiabatic non-radial pulsations on such stellar models.We predict a new instability domain of long-period gravity modes in the log g−log T eff plane at roughly 22000 K ≲ Te ≲ 50000 K and 4.67 ≲ log g ≲ 6.15, with a period range from ∼ 200 to ∼ 2000 s. Comparison with the three known pulsating He-rich subdwarfs shows that the ε mechanism can excite pulsations in models with similar surface properties except for modes with the shortest observed periods. Based on simple estimates we expect at least 3 stars in the current samples of hot-subdwarf stars to be pulsating by the ε mechanism. Our results could constitute a theoretical basis for future searches of pulsators in the Galactic field. |
publishDate |
2017 |
dc.date.none.fl_str_mv |
2017 |
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/10915/81693 |
url |
http://sedici.unlp.edu.ar/handle/10915/81693 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/2543-6376 info:eu-repo/semantics/altIdentifier/doi/10.1515/astro-2017-0431 |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
http://creativecommons.org/licenses/by-nc-nd/4.0/ Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International (CC BY-NC-ND 4.0) |
dc.format.none.fl_str_mv |
application/pdf 152-159 |
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_ |
1844616023991386112 |
score |
13.070432 |