Multiwavelength studies of WR 21a and its surroundings
- Autores
- Benaglia, Paula; Romero, Gustavo Esteban; Koribalski, B.; Pollock, A. M.T.
- Año de publicación
- 2005
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- We present results of high-resolution radio continuum observations towards the binary star WR 21a (Wack 2134) obtained with the Australia Telescope Compact Array (ATCA**) at 4.8 and 8.64 GHz. We detected the system at 4.8 GHz (6 cm) with a flux density of 0.25 ± 0.06 mJy and set an upper limit of 0.3 mJy at 8.64 GHz (3 cm). The derived spectral index of α < 0.3 (S v ∝ v α ) suggests the presence of non-thermal emission, probably originating in a colliding-wind region. A second, unrelated radio source was detected ∼10″ north of WR 21a at (RA, Dec) J2000 = (10 h 25 m 56 s .49, -57°48′34.4″), with flux densities of 0.36 and 0.55 mJy at 4.8 and 8.64 GHz, respectively, resulting in α = 0.72. H I observations in the area are dominated by absorption against the prominent H II region RCW 49. Analysis of a complete set of archived X-ray observations of WR 21a confirms its strong variability but throws into doubt previous suggestions by Reig (1999) of a period of years for the system. Finally, we comment on the association with the nearby EGRET source 3EG J1027-5817.
Facultad de Ciencias Astronómicas y Geofísicas - Materia
-
Ciencias Astronómicas
Gamma-rays: observations
ISM: bubbles
Radio continuum: stars
Stars: early-type
Stars: individual: WR 21a
Stars: winds, outflows - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- http://creativecommons.org/licenses/by-nc-sa/4.0/
- Repositorio
- Institución
- Universidad Nacional de La Plata
- OAI Identificador
- oai:sedici.unlp.edu.ar:10915/83278
Ver los metadatos del registro completo
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Multiwavelength studies of WR 21a and its surroundingsBenaglia, PaulaRomero, Gustavo EstebanKoribalski, B.Pollock, A. M.T.Ciencias AstronómicasGamma-rays: observationsISM: bubblesRadio continuum: starsStars: early-typeStars: individual: WR 21aStars: winds, outflowsWe present results of high-resolution radio continuum observations towards the binary star WR 21a (Wack 2134) obtained with the Australia Telescope Compact Array (ATCA**) at 4.8 and 8.64 GHz. We detected the system at 4.8 GHz (6 cm) with a flux density of 0.25 ± 0.06 mJy and set an upper limit of 0.3 mJy at 8.64 GHz (3 cm). The derived spectral index of α < 0.3 (S v ∝ v α ) suggests the presence of non-thermal emission, probably originating in a colliding-wind region. A second, unrelated radio source was detected ∼10″ north of WR 21a at (RA, Dec) J2000 = (10 h 25 m 56 s .49, -57°48′34.4″), with flux densities of 0.36 and 0.55 mJy at 4.8 and 8.64 GHz, respectively, resulting in α = 0.72. H I observations in the area are dominated by absorption against the prominent H II region RCW 49. Analysis of a complete set of archived X-ray observations of WR 21a confirms its strong variability but throws into doubt previous suggestions by Reig (1999) of a period of years for the system. Finally, we comment on the association with the nearby EGRET source 3EG J1027-5817.Facultad de Ciencias Astronómicas y Geofísicas2005info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionArticulohttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdf743-750http://sedici.unlp.edu.ar/handle/10915/83278enginfo:eu-repo/semantics/altIdentifier/issn/0004-6361info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20042617info: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:UNLP2025-09-29T11:15:46Zoai:sedici.unlp.edu.ar:10915/83278Institucionalhttp://sedici.unlp.edu.ar/Universidad públicaNo correspondehttp://sedici.unlp.edu.ar/oai/snrdalira@sedici.unlp.edu.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:13292025-09-29 11:15:46.914SEDICI (UNLP) - Universidad Nacional de La Platafalse |
dc.title.none.fl_str_mv |
Multiwavelength studies of WR 21a and its surroundings |
title |
Multiwavelength studies of WR 21a and its surroundings |
spellingShingle |
Multiwavelength studies of WR 21a and its surroundings Benaglia, Paula Ciencias Astronómicas Gamma-rays: observations ISM: bubbles Radio continuum: stars Stars: early-type Stars: individual: WR 21a Stars: winds, outflows |
title_short |
Multiwavelength studies of WR 21a and its surroundings |
title_full |
Multiwavelength studies of WR 21a and its surroundings |
title_fullStr |
Multiwavelength studies of WR 21a and its surroundings |
title_full_unstemmed |
Multiwavelength studies of WR 21a and its surroundings |
title_sort |
Multiwavelength studies of WR 21a and its surroundings |
dc.creator.none.fl_str_mv |
Benaglia, Paula Romero, Gustavo Esteban Koribalski, B. Pollock, A. M.T. |
author |
Benaglia, Paula |
author_facet |
Benaglia, Paula Romero, Gustavo Esteban Koribalski, B. Pollock, A. M.T. |
author_role |
author |
author2 |
Romero, Gustavo Esteban Koribalski, B. Pollock, A. M.T. |
author2_role |
author author author |
dc.subject.none.fl_str_mv |
Ciencias Astronómicas Gamma-rays: observations ISM: bubbles Radio continuum: stars Stars: early-type Stars: individual: WR 21a Stars: winds, outflows |
topic |
Ciencias Astronómicas Gamma-rays: observations ISM: bubbles Radio continuum: stars Stars: early-type Stars: individual: WR 21a Stars: winds, outflows |
dc.description.none.fl_txt_mv |
We present results of high-resolution radio continuum observations towards the binary star WR 21a (Wack 2134) obtained with the Australia Telescope Compact Array (ATCA**) at 4.8 and 8.64 GHz. We detected the system at 4.8 GHz (6 cm) with a flux density of 0.25 ± 0.06 mJy and set an upper limit of 0.3 mJy at 8.64 GHz (3 cm). The derived spectral index of α < 0.3 (S v ∝ v α ) suggests the presence of non-thermal emission, probably originating in a colliding-wind region. A second, unrelated radio source was detected ∼10″ north of WR 21a at (RA, Dec) J2000 = (10 h 25 m 56 s .49, -57°48′34.4″), with flux densities of 0.36 and 0.55 mJy at 4.8 and 8.64 GHz, respectively, resulting in α = 0.72. H I observations in the area are dominated by absorption against the prominent H II region RCW 49. Analysis of a complete set of archived X-ray observations of WR 21a confirms its strong variability but throws into doubt previous suggestions by Reig (1999) of a period of years for the system. Finally, we comment on the association with the nearby EGRET source 3EG J1027-5817. Facultad de Ciencias Astronómicas y Geofísicas |
description |
We present results of high-resolution radio continuum observations towards the binary star WR 21a (Wack 2134) obtained with the Australia Telescope Compact Array (ATCA**) at 4.8 and 8.64 GHz. We detected the system at 4.8 GHz (6 cm) with a flux density of 0.25 ± 0.06 mJy and set an upper limit of 0.3 mJy at 8.64 GHz (3 cm). The derived spectral index of α < 0.3 (S v ∝ v α ) suggests the presence of non-thermal emission, probably originating in a colliding-wind region. A second, unrelated radio source was detected ∼10″ north of WR 21a at (RA, Dec) J2000 = (10 h 25 m 56 s .49, -57°48′34.4″), with flux densities of 0.36 and 0.55 mJy at 4.8 and 8.64 GHz, respectively, resulting in α = 0.72. H I observations in the area are dominated by absorption against the prominent H II region RCW 49. Analysis of a complete set of archived X-ray observations of WR 21a confirms its strong variability but throws into doubt previous suggestions by Reig (1999) of a period of years for the system. Finally, we comment on the association with the nearby EGRET source 3EG J1027-5817. |
publishDate |
2005 |
dc.date.none.fl_str_mv |
2005 |
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/10915/83278 |
url |
http://sedici.unlp.edu.ar/handle/10915/83278 |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/issn/0004-6361 info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361:20042617 |
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) |
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openAccess |
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http://creativecommons.org/licenses/by-nc-sa/4.0/ Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International (CC BY-NC-SA 4.0) |
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