Investigation of the WR 11 field at decimeter wavelengths

Autores
Benaglia, Paula; del Palacio, Santiago; Ishwara-Chandra, C. H.; De Becker, M.; Isequilla, Natacha Laura; Saponara, Juliana
Año de publicación
2019
Idioma
inglés
Tipo de recurso
artículo
Estado
versión publicada
Descripción
The massive binary system WR 11 (γ2-Velorum) has recently been proposed as the counterpart of a Fermi source. If this association is correct, this system would be the second colliding wind binary detected in GeV γ-rays. However, the reported flux measurements from 1.4 to 8.64 GHz fail to establish the presence of nonthermal (synchrotron) emission from this source. Moreover, WR 11 is not the only radio source within the Fermi detection box. Other possible counterparts have been identified in archival data, some of which present strong nonthermal radio emission. We conducted arcsec-resolution observations toward WR 11 at very low frequencies (150-1400 MHz) where the nonthermal emission - if existent and not absorbed - is expected to dominate. We present a catalog of more than 400 radio emitters, among which a significant portion are detected at more than one frequency, including limited spectral index information. Twenty-one of these radio emitters are located within the Fermi significant emission. A search for counterparts for this last group pointed at MOST 0808-471; this source is 2´ away from WR 11 and is a promising candidate for high-energy emission, having a resolved structure along 325-1390 MHz. For this source, we reprocessed archive interferometric data up to 22.3 GHz and obtained a nonthermal radio spectral index of - 0.97 ± 0.09. However, multiwavelength observations of this source are required to establish its nature and to assess whether it can produce (part of) the observed γ-rays. WR 11 spectrum follows a spectral index of 0.74 ± 0.03 from 150 to 230 GHz, consistent with thermal emission. We interpret that any putative synchrotron radiation from the colliding-wind region of this relatively short-period system is absorbed in the photospheres of the individual components. Notwithstanding, the new radio data allowed us to derive a mass-loss rate of 2.5 × 10-5 M☉ yr-1, which, according to the latest models for γ-ray emission in WR 11, would suffice to provide the required kinetic power to feed nonthermal radiation processes.Full Table 4 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A99The radio data presented in this work were obtained with the Giant Metrewave Radio Telescope (GMRT). The GMRT is operated by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.
Fil: Benaglia, Paula. 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. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; Argentina
Fil: del Palacio, Santiago. 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: Ishwara-Chandra, C. H.. International Centre Of Theoretical Science. Tata Institute Of Fundamental Research; España
Fil: De Becker, M.. Université de Liège; Bélgica
Fil: Isequilla, Natacha Laura. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; Argentina
Fil: Saponara, Juliana. 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
Materia
RADIO CONTINUUM: GENERAL
RADIO CONTINUUM: STARS
RADIATION MECHANISMS: NON-THERMAL
STARS: INDIVIDUAL: WR11
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:11336/121345

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repository_id_str 3498
network_name_str CONICET Digital (CONICET)
spelling Investigation of the WR 11 field at decimeter wavelengthsBenaglia, Pauladel Palacio, SantiagoIshwara-Chandra, C. H.De Becker, M.Isequilla, Natacha LauraSaponara, JulianaRADIO CONTINUUM: GENERALRADIO CONTINUUM: STARSRADIATION MECHANISMS: NON-THERMALSTARS: INDIVIDUAL: WR11https://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1The massive binary system WR 11 (γ2-Velorum) has recently been proposed as the counterpart of a Fermi source. If this association is correct, this system would be the second colliding wind binary detected in GeV γ-rays. However, the reported flux measurements from 1.4 to 8.64 GHz fail to establish the presence of nonthermal (synchrotron) emission from this source. Moreover, WR 11 is not the only radio source within the Fermi detection box. Other possible counterparts have been identified in archival data, some of which present strong nonthermal radio emission. We conducted arcsec-resolution observations toward WR 11 at very low frequencies (150-1400 MHz) where the nonthermal emission - if existent and not absorbed - is expected to dominate. We present a catalog of more than 400 radio emitters, among which a significant portion are detected at more than one frequency, including limited spectral index information. Twenty-one of these radio emitters are located within the Fermi significant emission. A search for counterparts for this last group pointed at MOST 0808-471; this source is 2´ away from WR 11 and is a promising candidate for high-energy emission, having a resolved structure along 325-1390 MHz. For this source, we reprocessed archive interferometric data up to 22.3 GHz and obtained a nonthermal radio spectral index of - 0.97 ± 0.09. However, multiwavelength observations of this source are required to establish its nature and to assess whether it can produce (part of) the observed γ-rays. WR 11 spectrum follows a spectral index of 0.74 ± 0.03 from 150 to 230 GHz, consistent with thermal emission. We interpret that any putative synchrotron radiation from the colliding-wind region of this relatively short-period system is absorbed in the photospheres of the individual components. Notwithstanding, the new radio data allowed us to derive a mass-loss rate of 2.5 × 10-5 M☉ yr-1, which, according to the latest models for γ-ray emission in WR 11, would suffice to provide the required kinetic power to feed nonthermal radiation processes.Full Table 4 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A99The radio data presented in this work were obtained with the Giant Metrewave Radio Telescope (GMRT). The GMRT is operated by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.Fil: Benaglia, Paula. 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. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; ArgentinaFil: del Palacio, Santiago. 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: Ishwara-Chandra, C. H.. International Centre Of Theoretical Science. Tata Institute Of Fundamental Research; EspañaFil: De Becker, M.. Université de Liège; BélgicaFil: Isequilla, Natacha Laura. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; ArgentinaFil: Saponara, Juliana. 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; ArgentinaEDP Sciences2019-05info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/121345Benaglia, Paula; del Palacio, Santiago; Ishwara-Chandra, C. H.; De Becker, M.; Isequilla, Natacha Laura; et al.; Investigation of the WR 11 field at decimeter wavelengths; EDP Sciences; Astronomy and Astrophysics; 625; 5-2019; 99-1090004-6361CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/url/https://www.aanda.org/10.1051/0004-6361/201834971info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201834971info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T10:20:16Zoai:ri.conicet.gov.ar:11336/121345instacron: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 10:20:16.911CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse
dc.title.none.fl_str_mv Investigation of the WR 11 field at decimeter wavelengths
title Investigation of the WR 11 field at decimeter wavelengths
spellingShingle Investigation of the WR 11 field at decimeter wavelengths
Benaglia, Paula
RADIO CONTINUUM: GENERAL
RADIO CONTINUUM: STARS
RADIATION MECHANISMS: NON-THERMAL
STARS: INDIVIDUAL: WR11
title_short Investigation of the WR 11 field at decimeter wavelengths
title_full Investigation of the WR 11 field at decimeter wavelengths
title_fullStr Investigation of the WR 11 field at decimeter wavelengths
title_full_unstemmed Investigation of the WR 11 field at decimeter wavelengths
title_sort Investigation of the WR 11 field at decimeter wavelengths
dc.creator.none.fl_str_mv Benaglia, Paula
del Palacio, Santiago
Ishwara-Chandra, C. H.
De Becker, M.
Isequilla, Natacha Laura
Saponara, Juliana
author Benaglia, Paula
author_facet Benaglia, Paula
del Palacio, Santiago
Ishwara-Chandra, C. H.
De Becker, M.
Isequilla, Natacha Laura
Saponara, Juliana
author_role author
author2 del Palacio, Santiago
Ishwara-Chandra, C. H.
De Becker, M.
Isequilla, Natacha Laura
Saponara, Juliana
author2_role author
author
author
author
author
dc.subject.none.fl_str_mv RADIO CONTINUUM: GENERAL
RADIO CONTINUUM: STARS
RADIATION MECHANISMS: NON-THERMAL
STARS: INDIVIDUAL: WR11
topic RADIO CONTINUUM: GENERAL
RADIO CONTINUUM: STARS
RADIATION MECHANISMS: NON-THERMAL
STARS: INDIVIDUAL: WR11
purl_subject.fl_str_mv https://purl.org/becyt/ford/1.3
https://purl.org/becyt/ford/1
dc.description.none.fl_txt_mv The massive binary system WR 11 (γ2-Velorum) has recently been proposed as the counterpart of a Fermi source. If this association is correct, this system would be the second colliding wind binary detected in GeV γ-rays. However, the reported flux measurements from 1.4 to 8.64 GHz fail to establish the presence of nonthermal (synchrotron) emission from this source. Moreover, WR 11 is not the only radio source within the Fermi detection box. Other possible counterparts have been identified in archival data, some of which present strong nonthermal radio emission. We conducted arcsec-resolution observations toward WR 11 at very low frequencies (150-1400 MHz) where the nonthermal emission - if existent and not absorbed - is expected to dominate. We present a catalog of more than 400 radio emitters, among which a significant portion are detected at more than one frequency, including limited spectral index information. Twenty-one of these radio emitters are located within the Fermi significant emission. A search for counterparts for this last group pointed at MOST 0808-471; this source is 2´ away from WR 11 and is a promising candidate for high-energy emission, having a resolved structure along 325-1390 MHz. For this source, we reprocessed archive interferometric data up to 22.3 GHz and obtained a nonthermal radio spectral index of - 0.97 ± 0.09. However, multiwavelength observations of this source are required to establish its nature and to assess whether it can produce (part of) the observed γ-rays. WR 11 spectrum follows a spectral index of 0.74 ± 0.03 from 150 to 230 GHz, consistent with thermal emission. We interpret that any putative synchrotron radiation from the colliding-wind region of this relatively short-period system is absorbed in the photospheres of the individual components. Notwithstanding, the new radio data allowed us to derive a mass-loss rate of 2.5 × 10-5 M☉ yr-1, which, according to the latest models for γ-ray emission in WR 11, would suffice to provide the required kinetic power to feed nonthermal radiation processes.Full Table 4 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A99The radio data presented in this work were obtained with the Giant Metrewave Radio Telescope (GMRT). The GMRT is operated by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.
Fil: Benaglia, Paula. 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. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; Argentina
Fil: del Palacio, Santiago. 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: Ishwara-Chandra, C. H.. International Centre Of Theoretical Science. Tata Institute Of Fundamental Research; España
Fil: De Becker, M.. Université de Liège; Bélgica
Fil: Isequilla, Natacha Laura. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Observatorio Astronómico de La Plata - Sede Central; Argentina
Fil: Saponara, Juliana. 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
description The massive binary system WR 11 (γ2-Velorum) has recently been proposed as the counterpart of a Fermi source. If this association is correct, this system would be the second colliding wind binary detected in GeV γ-rays. However, the reported flux measurements from 1.4 to 8.64 GHz fail to establish the presence of nonthermal (synchrotron) emission from this source. Moreover, WR 11 is not the only radio source within the Fermi detection box. Other possible counterparts have been identified in archival data, some of which present strong nonthermal radio emission. We conducted arcsec-resolution observations toward WR 11 at very low frequencies (150-1400 MHz) where the nonthermal emission - if existent and not absorbed - is expected to dominate. We present a catalog of more than 400 radio emitters, among which a significant portion are detected at more than one frequency, including limited spectral index information. Twenty-one of these radio emitters are located within the Fermi significant emission. A search for counterparts for this last group pointed at MOST 0808-471; this source is 2´ away from WR 11 and is a promising candidate for high-energy emission, having a resolved structure along 325-1390 MHz. For this source, we reprocessed archive interferometric data up to 22.3 GHz and obtained a nonthermal radio spectral index of - 0.97 ± 0.09. However, multiwavelength observations of this source are required to establish its nature and to assess whether it can produce (part of) the observed γ-rays. WR 11 spectrum follows a spectral index of 0.74 ± 0.03 from 150 to 230 GHz, consistent with thermal emission. We interpret that any putative synchrotron radiation from the colliding-wind region of this relatively short-period system is absorbed in the photospheres of the individual components. Notwithstanding, the new radio data allowed us to derive a mass-loss rate of 2.5 × 10-5 M☉ yr-1, which, according to the latest models for γ-ray emission in WR 11, would suffice to provide the required kinetic power to feed nonthermal radiation processes.Full Table 4 is only available at the CDS via anonymous ftp to http://cdsarc.u-strasbg.fr (ftp://130.79.128.5) or via http://cdsarc.u-strasbg.fr/viz-bin/qcat?J/A+A/625/A99The radio data presented in this work were obtained with the Giant Metrewave Radio Telescope (GMRT). The GMRT is operated by the National Centre for Radio Astrophysics of the Tata Institute of Fundamental Research.
publishDate 2019
dc.date.none.fl_str_mv 2019-05
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/11336/121345
Benaglia, Paula; del Palacio, Santiago; Ishwara-Chandra, C. H.; De Becker, M.; Isequilla, Natacha Laura; et al.; Investigation of the WR 11 field at decimeter wavelengths; EDP Sciences; Astronomy and Astrophysics; 625; 5-2019; 99-109
0004-6361
CONICET Digital
CONICET
url http://hdl.handle.net/11336/121345
identifier_str_mv Benaglia, Paula; del Palacio, Santiago; Ishwara-Chandra, C. H.; De Becker, M.; Isequilla, Natacha Laura; et al.; Investigation of the WR 11 field at decimeter wavelengths; EDP Sciences; Astronomy and Astrophysics; 625; 5-2019; 99-109
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/url/https://www.aanda.org/10.1051/0004-6361/201834971
info:eu-repo/semantics/altIdentifier/doi/10.1051/0004-6361/201834971
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
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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