A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars

Autores
Cappa, Cristina Elisabeth; Goss, William Miller; van der Hucht, K. A.
Año de publicación
2004
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
We report the results of a survey of radio continuum emission of Galactic Wolf-Rayet (WR) stars north of δ = -46°. The observations were obtained at 8.46 GHz (3.6 cm) using the Very Large Array, with an angular resolution of ∼6″ × 9″ and typical rms noise of ∼0.04 mJy beam -1 . Our survey of 34 WR stars resulted in 15 definite, and five probable detections, 13 of these for the first time at radio wavelengths. All detections are unresolved (θ ≲ 5″). Time variations in flux are confirmed in the cases of WR 98a, 104, 105, and 125. WR 79a and WR 89 are also variable in flux, and we suspect they are also nonthermal emitters. Thus, of our sample 20%30% of the detected stars are nonthermal emitters. Average mass-loss rate determinations obtained excluding definite and suspected nonthermal cases give similar values for WN (all subtypes) and WC5-7 stars [M(WN) = (4 ± 3) × 10 -5 M ⊙ yr -1 and M(WC5-7) = (4 ± 2) × 10 -5 M× yr -1 ], while a lower value was obtained for WC8-9 stars [M(WC8-9) = (2 ± 1) × 10 -5 M ⊙ yr -1 ]. Uncertainties in stellar distances largely contribute to the observed scatter in mass-loss rates. Upper limits to the mass-loss rates were obtained in cases of undetected sources and for sources that probably show additional nonthermal emission.
Fil: Cappa, Cristina Elisabeth. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina
Fil: Goss, William Miller. National Radio Astronomy Observatory; Estados Unidos
Fil: van der Hucht, K. A.. Sron Netherlands Institute For Space Research; Países Bajos
Materia
STELLAR WINDS
WR 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:11336/76343
Acceder
id CONICETDig_3a563364d6533b3d119e4470e419ee2b
oai_identifier_str oai:ri.conicet.gov.ar:11336/76343
network_acronym_str CONICETDig
repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling A very large array 3.6 centimeter continuum survey of galactic wolf-rayet starsCappa, Cristina ElisabethGoss, William Millervan der Hucht, K. A.STELLAR WINDSWR STARSWe report the results of a survey of radio continuum emission of Galactic Wolf-Rayet (WR) stars north of δ = -46°. The observations were obtained at 8.46 GHz (3.6 cm) using the Very Large Array, with an angular resolution of ∼6″ × 9″ and typical rms noise of ∼0.04 mJy beam -1 . Our survey of 34 WR stars resulted in 15 definite, and five probable detections, 13 of these for the first time at radio wavelengths. All detections are unresolved (θ ≲ 5″). Time variations in flux are confirmed in the cases of WR 98a, 104, 105, and 125. WR 79a and WR 89 are also variable in flux, and we suspect they are also nonthermal emitters. Thus, of our sample 20%30% of the detected stars are nonthermal emitters. Average mass-loss rate determinations obtained excluding definite and suspected nonthermal cases give similar values for WN (all subtypes) and WC5-7 stars [M(WN) = (4 ± 3) × 10 -5 M ⊙ yr -1 and M(WC5-7) = (4 ± 2) × 10 -5 M× yr -1 ], while a lower value was obtained for WC8-9 stars [M(WC8-9) = (2 ± 1) × 10 -5 M ⊙ yr -1 ]. Uncertainties in stellar distances largely contribute to the observed scatter in mass-loss rates. Upper limits to the mass-loss rates were obtained in cases of undetected sources and for sources that probably show additional nonthermal emission.Fil: Cappa, Cristina Elisabeth. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; ArgentinaFil: Goss, William Miller. National Radio Astronomy Observatory; Estados UnidosFil: van der Hucht, K. A.. Sron Netherlands Institute For Space Research; Países BajosIOP Publishing2004-06info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/76343Cappa, Cristina Elisabeth; Goss, William Miller; van der Hucht, K. A. ; A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars; IOP Publishing; Astronomical Journal; 127; 5; 6-2004; 2885-28970004-6256CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1086/383286info:eu-repo/semantics/altIdentifier/url/https://iopscience.iop.org/article/10.1086/383286/metainfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:14:05Zoai:ri.conicet.gov.ar:11336/76343instacron: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 10:14:06.216CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
title A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
spellingShingle A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
Cappa, Cristina Elisabeth
STELLAR WINDS
WR STARS
title_short A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
title_full A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
title_fullStr A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
title_full_unstemmed A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
title_sort A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars
dc.creator.none.fl_str_mv Cappa, Cristina Elisabeth
Goss, William Miller
van der Hucht, K. A.
author Cappa, Cristina Elisabeth
author_facet Cappa, Cristina Elisabeth
Goss, William Miller
van der Hucht, K. A.
author_role author
author2 Goss, William Miller
van der Hucht, K. A.
author2_role author
author
dc.subject.none.fl_str_mv STELLAR WINDS
WR STARS
topic STELLAR WINDS
WR STARS
dc.description.none.fl_txt_mv We report the results of a survey of radio continuum emission of Galactic Wolf-Rayet (WR) stars north of δ = -46°. The observations were obtained at 8.46 GHz (3.6 cm) using the Very Large Array, with an angular resolution of ∼6″ × 9″ and typical rms noise of ∼0.04 mJy beam -1 . Our survey of 34 WR stars resulted in 15 definite, and five probable detections, 13 of these for the first time at radio wavelengths. All detections are unresolved (θ ≲ 5″). Time variations in flux are confirmed in the cases of WR 98a, 104, 105, and 125. WR 79a and WR 89 are also variable in flux, and we suspect they are also nonthermal emitters. Thus, of our sample 20%30% of the detected stars are nonthermal emitters. Average mass-loss rate determinations obtained excluding definite and suspected nonthermal cases give similar values for WN (all subtypes) and WC5-7 stars [M(WN) = (4 ± 3) × 10 -5 M ⊙ yr -1 and M(WC5-7) = (4 ± 2) × 10 -5 M× yr -1 ], while a lower value was obtained for WC8-9 stars [M(WC8-9) = (2 ± 1) × 10 -5 M ⊙ yr -1 ]. Uncertainties in stellar distances largely contribute to the observed scatter in mass-loss rates. Upper limits to the mass-loss rates were obtained in cases of undetected sources and for sources that probably show additional nonthermal emission.
Fil: Cappa, Cristina Elisabeth. Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Instituto Argentino de Radioastronomía. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto Argentino de Radioastronomía; Argentina
Fil: Goss, William Miller. National Radio Astronomy Observatory; Estados Unidos
Fil: van der Hucht, K. A.. Sron Netherlands Institute For Space Research; Países Bajos
description We report the results of a survey of radio continuum emission of Galactic Wolf-Rayet (WR) stars north of δ = -46°. The observations were obtained at 8.46 GHz (3.6 cm) using the Very Large Array, with an angular resolution of ∼6″ × 9″ and typical rms noise of ∼0.04 mJy beam -1 . Our survey of 34 WR stars resulted in 15 definite, and five probable detections, 13 of these for the first time at radio wavelengths. All detections are unresolved (θ ≲ 5″). Time variations in flux are confirmed in the cases of WR 98a, 104, 105, and 125. WR 79a and WR 89 are also variable in flux, and we suspect they are also nonthermal emitters. Thus, of our sample 20%30% of the detected stars are nonthermal emitters. Average mass-loss rate determinations obtained excluding definite and suspected nonthermal cases give similar values for WN (all subtypes) and WC5-7 stars [M(WN) = (4 ± 3) × 10 -5 M ⊙ yr -1 and M(WC5-7) = (4 ± 2) × 10 -5 M× yr -1 ], while a lower value was obtained for WC8-9 stars [M(WC8-9) = (2 ± 1) × 10 -5 M ⊙ yr -1 ]. Uncertainties in stellar distances largely contribute to the observed scatter in mass-loss rates. Upper limits to the mass-loss rates were obtained in cases of undetected sources and for sources that probably show additional nonthermal emission.
publishDate 2004
dc.date.none.fl_str_mv 2004-06
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/11336/76343
Cappa, Cristina Elisabeth; Goss, William Miller; van der Hucht, K. A. ; A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars; IOP Publishing; Astronomical Journal; 127; 5; 6-2004; 2885-2897
0004-6256
CONICET Digital
CONICET
url http://hdl.handle.net/11336/76343
identifier_str_mv Cappa, Cristina Elisabeth; Goss, William Miller; van der Hucht, K. A. ; A very large array 3.6 centimeter continuum survey of galactic wolf-rayet stars; IOP Publishing; Astronomical Journal; 127; 5; 6-2004; 2885-2897
0004-6256
CONICET Digital
CONICET
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/doi/10.1086/383286
info:eu-repo/semantics/altIdentifier/url/https://iopscience.iop.org/article/10.1086/383286/meta
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 IOP Publishing
publisher.none.fl_str_mv IOP Publishing
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
_version_ 1844614064514269184
score 13.070432

Publicaciones similares