Spatially resolved stis spectra of WR + OB binaries with colliding winds

We present spatially resolved spectra of the visual WR + OB massive binaries WR 86, WR 146, and WR 147, obtained with the Space Telescope Imaging Spectrograph on board the <i>Hubble Space Telescope</i>. The systems are classified as follows: WR 86 = WC 7 + BO III, WR 146 = WC 6 + O8 I-II...

Descripción completa

Detalles Bibliográficos
Autores: Lépine, Sébastien, Wallace, Debra, Shara, Michael M., Moffat, Anthony F. J., Niemelä, Virpi Sinikka
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2001
País:Argentina
Institución:Universidad Nacional de La Plata
Repositorio:SEDICI (UNLP)
Idioma:inglés
OAI Identifier:oai:sedici.unlp.edu.ar:10915/84791
Acceso en línea:http://sedici.unlp.edu.ar/handle/10915/84791
Access Level:acceso abierto
Palabra clave:Ciencias Astronómicas
Binaries: visual
Stars: early-type
Stars: winds, outflows
Stars: Wolf-Rayet
id AR_2e4433819ede28e9b53b2a3afb8ecbfa
oai_identifier_str oai:sedici.unlp.edu.ar:10915/84791
network_acronym_str AR
network_name_str Argentina
repository_id_str
spelling Spatially resolved stis spectra of WR + OB binaries with colliding windsLépine, SébastienWallace, DebraShara, Michael M.Moffat, Anthony F. J.Niemelä, Virpi SinikkaCiencias AstronómicasBinaries: visualStars: early-typeStars: winds, outflowsStars: Wolf-RayetWe present spatially resolved spectra of the visual WR + OB massive binaries WR 86, WR 146, and WR 147, obtained with the Space Telescope Imaging Spectrograph on board the <i>Hubble Space Telescope</i>. The systems are classified as follows: WR 86 = WC 7 + BO III, WR 146 = WC 6 + O8 I-IIf, WR 147 = WN 8 + O5-7 I-II(f). Both WR 146 and WR 147 are known to have strong nonthermal radio emission arising in a wind-wind collision shock zone between the WR and OB components. We find that the spectra of their O companions show Hα profiles in emission, indicative of large mass-loss rates and consistent with the colliding-wind model. Our spectra indicate that the B component in WR 86 has a low mass-loss rate, which possibly explains the fact that WR 86, despite being a long-period WR + OB binary, was not found to be a strong nonthermal radio emitter. Because of the small mass-loss rate of the B-star component in WR 86, the wind collision region must be closer to the B star and smaller in effective area, hence generating smaller amounts of nonthermal radio emission. Absolute magnitudes for all the stars are estimated based on the spectral types of the components (based on the tables by Schmidt-Kaler for OB stars and van der Hucht for WR stars) and compared with actual, observed magnitude differences. While the derived luminosities for the WC 7 and BO III stars in WR 86 are consistent with the observed magnitude difference, we find a discrepancy of at least 1.5 mag between the observed luminosities of the components in each of WR 146 and WR 147 and the absolute magnitudes expected from their spectral types. In both cases, it looks as though either the WR components are about 2 mag too bright for their spectral types or that the O components are about 2 mag too faint. We discuss possible explanations for this apparent discrepancy.Facultad de Ciencias Astronómicas y Geofísicas2001info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf3407-3418http://sedici.unlp.edu.ar/handle/10915/84791enginfo:eu-repo/semantics/altIdentifier/issn/0004-6256info:eu-repo/semantics/altIdentifier/doi/10.1086/324459info: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:UNLP2024-05-08T12:54:16Zoai:sedici.unlp.edu.ar:10915/84791Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292024-05-08 12:54:16.878SEDICI (UNLP) - Universidad Nacional de La Platafalse
dc.title.none.fl_str_mv Spatially resolved stis spectra of WR + OB binaries with colliding winds
title Spatially resolved stis spectra of WR + OB binaries with colliding winds
spellingShingle Spatially resolved stis spectra of WR + OB binaries with colliding winds
Lépine, Sébastien
Ciencias Astronómicas
Binaries: visual
Stars: early-type
Stars: winds, outflows
Stars: Wolf-Rayet
title_short Spatially resolved stis spectra of WR + OB binaries with colliding winds
title_full Spatially resolved stis spectra of WR + OB binaries with colliding winds
title_fullStr Spatially resolved stis spectra of WR + OB binaries with colliding winds
title_full_unstemmed Spatially resolved stis spectra of WR + OB binaries with colliding winds
title_sort Spatially resolved stis spectra of WR + OB binaries with colliding winds
dc.creator.none.fl_str_mv Lépine, Sébastien
Wallace, Debra
Shara, Michael M.
Moffat, Anthony F. J.
Niemelä, Virpi Sinikka
author Lépine, Sébastien
author_facet Lépine, Sébastien
Wallace, Debra
Shara, Michael M.
Moffat, Anthony F. J.
Niemelä, Virpi Sinikka
author_role author
author2 Wallace, Debra
Shara, Michael M.
Moffat, Anthony F. J.
Niemelä, Virpi Sinikka
author2_role author
author
author
author
dc.subject.none.fl_str_mv Ciencias Astronómicas
Binaries: visual
Stars: early-type
Stars: winds, outflows
Stars: Wolf-Rayet
topic Ciencias Astronómicas
Binaries: visual
Stars: early-type
Stars: winds, outflows
Stars: Wolf-Rayet
description We present spatially resolved spectra of the visual WR + OB massive binaries WR 86, WR 146, and WR 147, obtained with the Space Telescope Imaging Spectrograph on board the <i>Hubble Space Telescope</i>. The systems are classified as follows: WR 86 = WC 7 + BO III, WR 146 = WC 6 + O8 I-IIf, WR 147 = WN 8 + O5-7 I-II(f). Both WR 146 and WR 147 are known to have strong nonthermal radio emission arising in a wind-wind collision shock zone between the WR and OB components. We find that the spectra of their O companions show Hα profiles in emission, indicative of large mass-loss rates and consistent with the colliding-wind model. Our spectra indicate that the B component in WR 86 has a low mass-loss rate, which possibly explains the fact that WR 86, despite being a long-period WR + OB binary, was not found to be a strong nonthermal radio emitter. Because of the small mass-loss rate of the B-star component in WR 86, the wind collision region must be closer to the B star and smaller in effective area, hence generating smaller amounts of nonthermal radio emission. Absolute magnitudes for all the stars are estimated based on the spectral types of the components (based on the tables by Schmidt-Kaler for OB stars and van der Hucht for WR stars) and compared with actual, observed magnitude differences. While the derived luminosities for the WC 7 and BO III stars in WR 86 are consistent with the observed magnitude difference, we find a discrepancy of at least 1.5 mag between the observed luminosities of the components in each of WR 146 and WR 147 and the absolute magnitudes expected from their spectral types. In both cases, it looks as though either the WR components are about 2 mag too bright for their spectral types or that the O components are about 2 mag too faint. We discuss possible explanations for this apparent discrepancy.
publishDate 2001
dc.date.none.fl_str_mv 2001
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/10915/84791
url http://sedici.unlp.edu.ar/handle/10915/84791
dc.language.none.fl_str_mv eng
language eng
dc.relation.none.fl_str_mv info:eu-repo/semantics/altIdentifier/issn/0004-6256
info:eu-repo/semantics/altIdentifier/doi/10.1086/324459
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
3407-3418
dc.source.none.fl_str_mv reponame:SEDICI (UNLP)
instname:Universidad Nacional de La Plata
instacron:UNLP
instname_str Universidad Nacional de La Plata
instacron_str UNLP
institution UNLP
reponame_str SEDICI (UNLP)
collection SEDICI (UNLP)
repository.name.fl_str_mv SEDICI (UNLP) - Universidad Nacional de La Plata
repository.mail.fl_str_mv alira@sedici.unlp.edu.ar
_version_ 1799194212939333632
score 15,812429

Similares en LA Referencia