Testing the predicted mass-loss bi-stability jump at radio wavelengths

Autores
Benaglia, Paula; Vink, J. S.; Marti, Josep; Maiz Apellaniz, J.; Koribalski, Bärbel; Crowther, P. A.
Año de publicación
2007
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
Context. Massive stars play a dominant role in the Universe, but one of the main drivers for their evolution, their mass loss, remains poorly understood. Aims. In this study, we test the theoretically predicted mass-loss behaviour as a function of stellar effective temperature across the so-called “bi-stability” jump. Methods. We observe OB supergiants in the spectral range O8-B3 at radio wavelengths to measure their thermal radio flux densities, and complement these measurements with data from the literature. We derive the radio mass-loss rates and wind efficiencies, and compare our results with Hα mass-loss rates and predictions based on radiation-driven wind models. Results. The wind efficiency shows the possible presence of a local maximum around an effective temperature of 21 000 K – in qualitative agreement with predictions. Furthermore, we find that the absolute values of the radio mass-loss rates show good agreement with empirical Hα rates derived assuming homogeneous winds – for the spectral range under consideration. However, the empirical mass-loss rates are larger (by a factor of a few) than the predicted rates from radiation-driven wind theory for objects above the bi-stability jump (BSJ) temperature, whilst they are smaller (by a factor of a few) for stars below the BSJ temperature. The reason for these discrepancies remains as yet unresolved. A new wind momenta-luminosity relation (WLR) for O8-B0 stars has been derived using the radio observations. The validity of the WLR as a function of the fitting parameter related to the force multiplier αeff (Kudritzki & Puls 2000) is discussed. Conclusions. Our most interesting finding is that the qualitative behaviour of the empirical wind efficiencies with effective temperature is in line with the predicted behaviour, and this presents the first hint of empirical evidence for the predicted mass-loss bi-stability jump. However, a larger sample of stars around the BSJ needs to be observed to confirm this finding.
Fil: Benaglia, Paula. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomia; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina
Fil: Vink, J. S.. Keele University; Reino Unido
Fil: Marti, Josep. Universidad de Jaén; España
Fil: Maiz Apellaniz, J.. Instituto de Astrofísica de Andalucía; España
Fil: Koribalski, Bärbel. Australia Telescope National Facility; Australia
Fil: Crowther, P. A.. University of Sheffield; Reino Unido
Materia
Massive stars
Radio continuum
Early type stars
Mass loss
Star winds
Outflows
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:11336/22322

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network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Testing the predicted mass-loss bi-stability jump at radio wavelengthsBenaglia, PaulaVink, J. S.Marti, JosepMaiz Apellaniz, J.Koribalski, BärbelCrowther, P. A.Massive starsRadio continuumEarly type starsMass lossStar windsOutflowshttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1Context. Massive stars play a dominant role in the Universe, but one of the main drivers for their evolution, their mass loss, remains poorly understood. Aims. In this study, we test the theoretically predicted mass-loss behaviour as a function of stellar effective temperature across the so-called “bi-stability” jump. Methods. We observe OB supergiants in the spectral range O8-B3 at radio wavelengths to measure their thermal radio flux densities, and complement these measurements with data from the literature. We derive the radio mass-loss rates and wind efficiencies, and compare our results with Hα mass-loss rates and predictions based on radiation-driven wind models. Results. The wind efficiency shows the possible presence of a local maximum around an effective temperature of 21 000 K – in qualitative agreement with predictions. Furthermore, we find that the absolute values of the radio mass-loss rates show good agreement with empirical Hα rates derived assuming homogeneous winds – for the spectral range under consideration. However, the empirical mass-loss rates are larger (by a factor of a few) than the predicted rates from radiation-driven wind theory for objects above the bi-stability jump (BSJ) temperature, whilst they are smaller (by a factor of a few) for stars below the BSJ temperature. The reason for these discrepancies remains as yet unresolved. A new wind momenta-luminosity relation (WLR) for O8-B0 stars has been derived using the radio observations. The validity of the WLR as a function of the fitting parameter related to the force multiplier αeff (Kudritzki & Puls 2000) is discussed. Conclusions. Our most interesting finding is that the qualitative behaviour of the empirical wind efficiencies with effective temperature is in line with the predicted behaviour, and this presents the first hint of empirical evidence for the predicted mass-loss bi-stability jump. However, a larger sample of stars around the BSJ needs to be observed to confirm this finding.Fil: Benaglia, Paula. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomia; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; ArgentinaFil: Vink, J. S.. Keele University; Reino UnidoFil: Marti, Josep. Universidad de Jaén; EspañaFil: Maiz Apellaniz, J.. Instituto de Astrofísica de Andalucía; EspañaFil: Koribalski, Bärbel. Australia Telescope National Facility; AustraliaFil: Crowther, P. A.. University of Sheffield; Reino UnidoEdp Sciences2007-12info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/22322Benaglia, Paula; Vink, J. S.; Marti, Josep; Maiz Apellaniz, J.; Koribalski, Bärbel; et al.; Testing the predicted mass-loss bi-stability jump at radio wavelengths; Edp Sciences; Astronomy And Astrophysics; 467; 3; 12-2007; 1265-12740004-6361CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20077139info:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/articles/aa/abs/2007/21/aa7139-07/aa7139-07.htmlinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:37:59Zoai:ri.conicet.gov.ar:11336/22322instacron: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 10:38:00.167CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Testing the predicted mass-loss bi-stability jump at radio wavelengths
title Testing the predicted mass-loss bi-stability jump at radio wavelengths
spellingShingle Testing the predicted mass-loss bi-stability jump at radio wavelengths
Benaglia, Paula
Massive stars
Radio continuum
Early type stars
Mass loss
Star winds
Outflows
title_short Testing the predicted mass-loss bi-stability jump at radio wavelengths
title_full Testing the predicted mass-loss bi-stability jump at radio wavelengths
title_fullStr Testing the predicted mass-loss bi-stability jump at radio wavelengths
title_full_unstemmed Testing the predicted mass-loss bi-stability jump at radio wavelengths
title_sort Testing the predicted mass-loss bi-stability jump at radio wavelengths
dc.creator.none.fl_str_mv Benaglia, Paula
Vink, J. S.
Marti, Josep
Maiz Apellaniz, J.
Koribalski, Bärbel
Crowther, P. A.
author Benaglia, Paula
author_facet Benaglia, Paula
Vink, J. S.
Marti, Josep
Maiz Apellaniz, J.
Koribalski, Bärbel
Crowther, P. A.
author_role author
author2 Vink, J. S.
Marti, Josep
Maiz Apellaniz, J.
Koribalski, Bärbel
Crowther, P. A.
author2_role author
author
author
author
author
dc.subject.none.fl_str_mv Massive stars
Radio continuum
Early type stars
Mass loss
Star winds
Outflows
topic Massive stars
Radio continuum
Early type stars
Mass loss
Star winds
Outflows
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv Context. Massive stars play a dominant role in the Universe, but one of the main drivers for their evolution, their mass loss, remains poorly understood. Aims. In this study, we test the theoretically predicted mass-loss behaviour as a function of stellar effective temperature across the so-called “bi-stability” jump. Methods. We observe OB supergiants in the spectral range O8-B3 at radio wavelengths to measure their thermal radio flux densities, and complement these measurements with data from the literature. We derive the radio mass-loss rates and wind efficiencies, and compare our results with Hα mass-loss rates and predictions based on radiation-driven wind models. Results. The wind efficiency shows the possible presence of a local maximum around an effective temperature of 21 000 K – in qualitative agreement with predictions. Furthermore, we find that the absolute values of the radio mass-loss rates show good agreement with empirical Hα rates derived assuming homogeneous winds – for the spectral range under consideration. However, the empirical mass-loss rates are larger (by a factor of a few) than the predicted rates from radiation-driven wind theory for objects above the bi-stability jump (BSJ) temperature, whilst they are smaller (by a factor of a few) for stars below the BSJ temperature. The reason for these discrepancies remains as yet unresolved. A new wind momenta-luminosity relation (WLR) for O8-B0 stars has been derived using the radio observations. The validity of the WLR as a function of the fitting parameter related to the force multiplier αeff (Kudritzki & Puls 2000) is discussed. Conclusions. Our most interesting finding is that the qualitative behaviour of the empirical wind efficiencies with effective temperature is in line with the predicted behaviour, and this presents the first hint of empirical evidence for the predicted mass-loss bi-stability jump. However, a larger sample of stars around the BSJ needs to be observed to confirm this finding.
Fil: Benaglia, Paula. Provincia de Buenos Aires. Gobernación. Comision de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomia; Argentina. Universidad Nacional de la Plata. Facultad de Ciencias Astronómicas y Geofísicas; Argentina
Fil: Vink, J. S.. Keele University; Reino Unido
Fil: Marti, Josep. Universidad de Jaén; España
Fil: Maiz Apellaniz, J.. Instituto de Astrofísica de Andalucía; España
Fil: Koribalski, Bärbel. Australia Telescope National Facility; Australia
Fil: Crowther, P. A.. University of Sheffield; Reino Unido
description Context. Massive stars play a dominant role in the Universe, but one of the main drivers for their evolution, their mass loss, remains poorly understood. Aims. In this study, we test the theoretically predicted mass-loss behaviour as a function of stellar effective temperature across the so-called “bi-stability” jump. Methods. We observe OB supergiants in the spectral range O8-B3 at radio wavelengths to measure their thermal radio flux densities, and complement these measurements with data from the literature. We derive the radio mass-loss rates and wind efficiencies, and compare our results with Hα mass-loss rates and predictions based on radiation-driven wind models. Results. The wind efficiency shows the possible presence of a local maximum around an effective temperature of 21 000 K – in qualitative agreement with predictions. Furthermore, we find that the absolute values of the radio mass-loss rates show good agreement with empirical Hα rates derived assuming homogeneous winds – for the spectral range under consideration. However, the empirical mass-loss rates are larger (by a factor of a few) than the predicted rates from radiation-driven wind theory for objects above the bi-stability jump (BSJ) temperature, whilst they are smaller (by a factor of a few) for stars below the BSJ temperature. The reason for these discrepancies remains as yet unresolved. A new wind momenta-luminosity relation (WLR) for O8-B0 stars has been derived using the radio observations. The validity of the WLR as a function of the fitting parameter related to the force multiplier αeff (Kudritzki & Puls 2000) is discussed. Conclusions. Our most interesting finding is that the qualitative behaviour of the empirical wind efficiencies with effective temperature is in line with the predicted behaviour, and this presents the first hint of empirical evidence for the predicted mass-loss bi-stability jump. However, a larger sample of stars around the BSJ needs to be observed to confirm this finding.
publishDate 2007
dc.date.none.fl_str_mv 2007-12
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/11336/22322
Benaglia, Paula; Vink, J. S.; Marti, Josep; Maiz Apellaniz, J.; Koribalski, Bärbel; et al.; Testing the predicted mass-loss bi-stability jump at radio wavelengths; Edp Sciences; Astronomy And Astrophysics; 467; 3; 12-2007; 1265-1274
0004-6361
CONICET Digital
CONICET
url http://hdl.handle.net/11336/22322
identifier_str_mv Benaglia, Paula; Vink, J. S.; Marti, Josep; Maiz Apellaniz, J.; Koribalski, Bärbel; et al.; Testing the predicted mass-loss bi-stability jump at radio wavelengths; Edp Sciences; Astronomy And Astrophysics; 467; 3; 12-2007; 1265-1274
0004-6361
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20077139
info:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/articles/aa/abs/2007/21/aa7139-07/aa7139-07.html
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
dc.publisher.none.fl_str_mv Edp Sciences
publisher.none.fl_str_mv Edp Sciences
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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