He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage
- Autores
- Teodoro, M.; Damineli, A.; Arias, J. I.; de Araújo, F. X.; Barba, Rodolfo Hector; Corcoran, Michael; Borges Fernandes, M.; Fernandez Lajus, Eduardo Eusebio; Fraga, L.; Gamen, Roberto Claudio; Gonzalez, Jorge Federico; Groh, J. H.; Marshall, J. L.; McGregor, P. J.; Morrell, N.; Nicholls, D. C.; Parkin, E. R.; Pereira, C. B.; Phillips, M. M.; Solivella, Gladys Rebeca; Steiner, J. E.; Stritzinger, M.; Thompson, I.; Torres, C. A. O.; Torres, M. A. P.; Zevallos Herencia, M. I.
- Año de publicación
- 2012
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- The periodic spectroscopic events in η Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision (WWC) boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All of them have problems explaining all the observed phenomena. To better understand the nature of the cyclic events, we performed a dense monitoring of η Carinae with five Southern telescopes during the 2009 low-excitation event, resulting in a set of data of unprecedented quality and sampling. The intrinsic luminosity of the He II λ4686 emission line (L 310 L) just before periastron reveals the presence of a very luminous transient source of extreme UV radiation emitted in the WWC region. Clumps in the primary's wind probably explain the flare-like behavior of both the X-ray and He II λ4686 light curves. After a short-lived minimum, He II λ4686 emission rises again to a new maximum, when X-rays are still absent or very weak. We interpret this as a collapse of the WWC onto the "surface" of the secondary star, switching off the hard X-ray source and diminishing the WWC shock cone. The recovery from this state is controlled by the momentum balance between the secondary's wind and the clumps in the primary's wind.
Fil: Teodoro, M.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo ; Brasil
Fil: Damineli, A.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; Brasil
Fil: Arias, J. I.. Departamento de Fısica. Universidad de La Serena; Chile
Fil: de Araújo, F. X.. Observatorio Nacional. Rio de Janeiro; Brasil
Fil: Barba, R. H.. Departamento de Fısica. Universidad de La Serena; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina
Fil: Corcoran, M. F.. 5 CRESST and X-ray Astrophysics Laboratory. NASA/Goddard Space Flight Center; Estados Unidos
Fil: Borges Fernandes, M.. Observatorio Nacional. Rio de Janeiro; Brasil
Fil: Fernandez Lajus, E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: Fraga, L.. Southern Observatory for Astrophysical Research. La Serena; Chile
Fil: Gamen, Roberto Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina
Fil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina
Fil: Groh, J. H.. Max-Planck-Institute fur Radioastronomie; Alemania
Fil: Marshall, J. L.. Department of Physics and Astronomy. Texas A&M University; Estados Unidos
Fil: McGregor, P. J.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia
Fil: Morrell, N.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; Chile
Fil: Nicholls, D. C.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia
Fil: Parkin, E. R.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia
Fil: Pereira, C. B.. Observatorio Nacional. Rio de Janeiro; Brasil
Fil: Phillips, M. M.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; Chile
Fil: Solivella, G. R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Facultad de Ciencias Astronomicas y Geofisicas de La Plata; Argentina
Fil: Steiner, J. E.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; Brasil
Fil: Stritzinger, M.. The Oskar Klein Centre. Department of Astronomy. Stockholm University; Suiza. Dark Cosmology Centre. Niels Bohr Institute, University of Copenhagen; Dinamarca
Fil: Thompson, I.. Observatories of the Carnegie Institution. California; Estados Unidos
Fil: Torres, C. A. O.. 4 Laboratorio Nacional de Astrofısica,; Brasil
Fil: Torres, M. A. P.. Harvard-Smithsonian Center for Astrophysics. Cambridge; Estados Unidos. SRON, Netherlands Institute for Space Research; Países Bajos
Fil: Zevallos Herencia, M. I.. Observatorio Nacional. Rio de Janeiro; Brasil - Materia
-
LINE: PROFILES
STARS: EARLY-TYPE
STARS: INDIVIDUAL (ETA CARINAE)
STARS: MASSIVE - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc/2.5/ar/
- Repositorio
.jpg)
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/93051
Ver los metadatos del registro completo
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He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron PassageTeodoro, M.Damineli, A.Arias, J. I.de Araújo, F. X.Barba, Rodolfo HectorCorcoran, MichaelBorges Fernandes, M.Fernandez Lajus, Eduardo EusebioFraga, L.Gamen, Roberto ClaudioGonzalez, Jorge FedericoGroh, J. H.Marshall, J. L.McGregor, P. J.Morrell, N.Nicholls, D. C.Parkin, E. R.Pereira, C. B.Phillips, M. M.Solivella, Gladys RebecaSteiner, J. E.Stritzinger, M.Thompson, I.Torres, C. A. O.Torres, M. A. P.Zevallos Herencia, M. I.LINE: PROFILESSTARS: EARLY-TYPESTARS: INDIVIDUAL (ETA CARINAE)STARS: MASSIVEhttps://purl.org/becyt/ford/1.3https://purl.org/becyt/ford/1The periodic spectroscopic events in η Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision (WWC) boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All of them have problems explaining all the observed phenomena. To better understand the nature of the cyclic events, we performed a dense monitoring of η Carinae with five Southern telescopes during the 2009 low-excitation event, resulting in a set of data of unprecedented quality and sampling. The intrinsic luminosity of the He II λ4686 emission line (L 310 L) just before periastron reveals the presence of a very luminous transient source of extreme UV radiation emitted in the WWC region. Clumps in the primary's wind probably explain the flare-like behavior of both the X-ray and He II λ4686 light curves. After a short-lived minimum, He II λ4686 emission rises again to a new maximum, when X-rays are still absent or very weak. We interpret this as a collapse of the WWC onto the "surface" of the secondary star, switching off the hard X-ray source and diminishing the WWC shock cone. The recovery from this state is controlled by the momentum balance between the secondary's wind and the clumps in the primary's wind.Fil: Teodoro, M.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo ; BrasilFil: Damineli, A.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; BrasilFil: Arias, J. I.. Departamento de Fısica. Universidad de La Serena; ChileFil: de Araújo, F. X.. Observatorio Nacional. Rio de Janeiro; BrasilFil: Barba, R. H.. Departamento de Fısica. Universidad de La Serena; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Corcoran, M. F.. 5 CRESST and X-ray Astrophysics Laboratory. NASA/Goddard Space Flight Center; Estados UnidosFil: Borges Fernandes, M.. Observatorio Nacional. Rio de Janeiro; BrasilFil: Fernandez Lajus, E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Fraga, L.. Southern Observatory for Astrophysical Research. La Serena; ChileFil: Gamen, Roberto Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; ArgentinaFil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; ArgentinaFil: Groh, J. H.. Max-Planck-Institute fur Radioastronomie; AlemaniaFil: Marshall, J. L.. Department of Physics and Astronomy. Texas A&M University; Estados UnidosFil: McGregor, P. J.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; AustraliaFil: Morrell, N.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; ChileFil: Nicholls, D. C.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; AustraliaFil: Parkin, E. R.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; AustraliaFil: Pereira, C. B.. Observatorio Nacional. Rio de Janeiro; BrasilFil: Phillips, M. M.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; ChileFil: Solivella, G. R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Facultad de Ciencias Astronomicas y Geofisicas de La Plata; ArgentinaFil: Steiner, J. E.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; BrasilFil: Stritzinger, M.. The Oskar Klein Centre. Department of Astronomy. Stockholm University; Suiza. Dark Cosmology Centre. Niels Bohr Institute, University of Copenhagen; DinamarcaFil: Thompson, I.. Observatories of the Carnegie Institution. California; Estados UnidosFil: Torres, C. A. O.. 4 Laboratorio Nacional de Astrofısica,; BrasilFil: Torres, M. A. P.. Harvard-Smithsonian Center for Astrophysics. Cambridge; Estados Unidos. SRON, Netherlands Institute for Space Research; Países BajosFil: Zevallos Herencia, M. I.. Observatorio Nacional. Rio de Janeiro; BrasilIOP Publishing2012-02-10info: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/11336/93051Teodoro, M.; Damineli, A.; Arias, J. I.; de Araújo, F. X.; Barba, Rodolfo Hector; et al.; He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage; IOP Publishing; Astrophysical Journal; 746; 1; 10-2-2012; 1-150004-637XCONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/10.1088/0004-637X/746/1/73info:eu-repo/semantics/altIdentifier/url/https://arxiv.org/abs/1104.2276info:eu-repo/semantics/altIdentifier/url/https://iopscience.iop.org/article/10.1088/0004-637X/746/1/73info:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-10-22T11:09:42Zoai:ri.conicet.gov.ar:11336/93051instacron: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:34982025-10-22 11:09:43.105CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
| dc.title.none.fl_str_mv |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| title |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| spellingShingle |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage Teodoro, M. LINE: PROFILES STARS: EARLY-TYPE STARS: INDIVIDUAL (ETA CARINAE) STARS: MASSIVE |
| title_short |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| title_full |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| title_fullStr |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| title_full_unstemmed |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| title_sort |
He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage |
| dc.creator.none.fl_str_mv |
Teodoro, M. Damineli, A. Arias, J. I. de Araújo, F. X. Barba, Rodolfo Hector Corcoran, Michael Borges Fernandes, M. Fernandez Lajus, Eduardo Eusebio Fraga, L. Gamen, Roberto Claudio Gonzalez, Jorge Federico Groh, J. H. Marshall, J. L. McGregor, P. J. Morrell, N. Nicholls, D. C. Parkin, E. R. Pereira, C. B. Phillips, M. M. Solivella, Gladys Rebeca Steiner, J. E. Stritzinger, M. Thompson, I. Torres, C. A. O. Torres, M. A. P. Zevallos Herencia, M. I. |
| author |
Teodoro, M. |
| author_facet |
Teodoro, M. Damineli, A. Arias, J. I. de Araújo, F. X. Barba, Rodolfo Hector Corcoran, Michael Borges Fernandes, M. Fernandez Lajus, Eduardo Eusebio Fraga, L. Gamen, Roberto Claudio Gonzalez, Jorge Federico Groh, J. H. Marshall, J. L. McGregor, P. J. Morrell, N. Nicholls, D. C. Parkin, E. R. Pereira, C. B. Phillips, M. M. Solivella, Gladys Rebeca Steiner, J. E. Stritzinger, M. Thompson, I. Torres, C. A. O. Torres, M. A. P. Zevallos Herencia, M. I. |
| author_role |
author |
| author2 |
Damineli, A. Arias, J. I. de Araújo, F. X. Barba, Rodolfo Hector Corcoran, Michael Borges Fernandes, M. Fernandez Lajus, Eduardo Eusebio Fraga, L. Gamen, Roberto Claudio Gonzalez, Jorge Federico Groh, J. H. Marshall, J. L. McGregor, P. J. Morrell, N. Nicholls, D. C. Parkin, E. R. Pereira, C. B. Phillips, M. M. Solivella, Gladys Rebeca Steiner, J. E. Stritzinger, M. Thompson, I. Torres, C. A. O. Torres, M. A. P. Zevallos Herencia, M. I. |
| author2_role |
author author author author author author author author author author author author author author author author author author author author author author author author author |
| dc.subject.none.fl_str_mv |
LINE: PROFILES STARS: EARLY-TYPE STARS: INDIVIDUAL (ETA CARINAE) STARS: MASSIVE |
| topic |
LINE: PROFILES STARS: EARLY-TYPE STARS: INDIVIDUAL (ETA CARINAE) STARS: MASSIVE |
| 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 periodic spectroscopic events in η Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision (WWC) boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All of them have problems explaining all the observed phenomena. To better understand the nature of the cyclic events, we performed a dense monitoring of η Carinae with five Southern telescopes during the 2009 low-excitation event, resulting in a set of data of unprecedented quality and sampling. The intrinsic luminosity of the He II λ4686 emission line (L 310 L) just before periastron reveals the presence of a very luminous transient source of extreme UV radiation emitted in the WWC region. Clumps in the primary's wind probably explain the flare-like behavior of both the X-ray and He II λ4686 light curves. After a short-lived minimum, He II λ4686 emission rises again to a new maximum, when X-rays are still absent or very weak. We interpret this as a collapse of the WWC onto the "surface" of the secondary star, switching off the hard X-ray source and diminishing the WWC shock cone. The recovery from this state is controlled by the momentum balance between the secondary's wind and the clumps in the primary's wind. Fil: Teodoro, M.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo ; Brasil Fil: Damineli, A.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; Brasil Fil: Arias, J. I.. Departamento de Fısica. Universidad de La Serena; Chile Fil: de Araújo, F. X.. Observatorio Nacional. Rio de Janeiro; Brasil Fil: Barba, R. H.. Departamento de Fısica. Universidad de La Serena; Chile. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina Fil: Corcoran, M. F.. 5 CRESST and X-ray Astrophysics Laboratory. NASA/Goddard Space Flight Center; Estados Unidos Fil: Borges Fernandes, M.. Observatorio Nacional. Rio de Janeiro; Brasil Fil: Fernandez Lajus, E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina Fil: Fraga, L.. Southern Observatory for Astrophysical Research. La Serena; Chile Fil: Gamen, Roberto Claudio. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina Fil: Gonzalez, Jorge Federico. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio. Universidad Nacional de San Juan. Instituto de Ciencias Astronómicas, de la Tierra y del Espacio; Argentina Fil: Groh, J. H.. Max-Planck-Institute fur Radioastronomie; Alemania Fil: Marshall, J. L.. Department of Physics and Astronomy. Texas A&M University; Estados Unidos Fil: McGregor, P. J.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia Fil: Morrell, N.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; Chile Fil: Nicholls, D. C.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia Fil: Parkin, E. R.. Research School of Astronomy and Astrophysics (RSAA). Mount Stromlo Observatory; Australia Fil: Pereira, C. B.. Observatorio Nacional. Rio de Janeiro; Brasil Fil: Phillips, M. M.. Las Campanas Observatory. Observatories of the Carnegie Institution of Washington; Chile Fil: Solivella, G. R.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Astrofísica La Plata. Universidad Nacional de La Plata. Facultad de Ciencias Astronómicas y Geofísicas. Instituto de Astrofísica La Plata; Argentina. Facultad de Ciencias Astronomicas y Geofisicas de La Plata; Argentina Fil: Steiner, J. E.. Instituto de Astronomía, Geofısica e Ciencias Atmosfericas. Universidade de Sao Paulo; Brasil Fil: Stritzinger, M.. The Oskar Klein Centre. Department of Astronomy. Stockholm University; Suiza. Dark Cosmology Centre. Niels Bohr Institute, University of Copenhagen; Dinamarca Fil: Thompson, I.. Observatories of the Carnegie Institution. California; Estados Unidos Fil: Torres, C. A. O.. 4 Laboratorio Nacional de Astrofısica,; Brasil Fil: Torres, M. A. P.. Harvard-Smithsonian Center for Astrophysics. Cambridge; Estados Unidos. SRON, Netherlands Institute for Space Research; Países Bajos Fil: Zevallos Herencia, M. I.. Observatorio Nacional. Rio de Janeiro; Brasil |
| description |
The periodic spectroscopic events in η Carinae are now well established and occur near the periastron passage of two massive stars in a very eccentric orbit. Several mechanisms have been proposed to explain the variations of different spectral features, such as an eclipse by the wind-wind collision (WWC) boundary, a shell ejection from the primary star or accretion of its wind onto the secondary. All of them have problems explaining all the observed phenomena. To better understand the nature of the cyclic events, we performed a dense monitoring of η Carinae with five Southern telescopes during the 2009 low-excitation event, resulting in a set of data of unprecedented quality and sampling. The intrinsic luminosity of the He II λ4686 emission line (L 310 L) just before periastron reveals the presence of a very luminous transient source of extreme UV radiation emitted in the WWC region. Clumps in the primary's wind probably explain the flare-like behavior of both the X-ray and He II λ4686 light curves. After a short-lived minimum, He II λ4686 emission rises again to a new maximum, when X-rays are still absent or very weak. We interpret this as a collapse of the WWC onto the "surface" of the secondary star, switching off the hard X-ray source and diminishing the WWC shock cone. The recovery from this state is controlled by the momentum balance between the secondary's wind and the clumps in the primary's wind. |
| publishDate |
2012 |
| dc.date.none.fl_str_mv |
2012-02-10 |
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info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
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article |
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publishedVersion |
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http://hdl.handle.net/11336/93051 Teodoro, M.; Damineli, A.; Arias, J. I.; de Araújo, F. X.; Barba, Rodolfo Hector; et al.; He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage; IOP Publishing; Astrophysical Journal; 746; 1; 10-2-2012; 1-15 0004-637X CONICET Digital CONICET |
| url |
http://hdl.handle.net/11336/93051 |
| identifier_str_mv |
Teodoro, M.; Damineli, A.; Arias, J. I.; de Araújo, F. X.; Barba, Rodolfo Hector; et al.; He II lambda4686 in Eta Carinae: Collapse of the Wind-Wind Collision Region during Periastron Passage; IOP Publishing; Astrophysical Journal; 746; 1; 10-2-2012; 1-15 0004-637X CONICET Digital CONICET |
| dc.language.none.fl_str_mv |
eng |
| language |
eng |
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info:eu-repo/semantics/altIdentifier/doi/10.1088/0004-637X/746/1/73 info:eu-repo/semantics/altIdentifier/url/https://arxiv.org/abs/1104.2276 info:eu-repo/semantics/altIdentifier/url/https://iopscience.iop.org/article/10.1088/0004-637X/746/1/73 |
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info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc/2.5/ar/ |
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openAccess |
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https://creativecommons.org/licenses/by-nc/2.5/ar/ |
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IOP Publishing |
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IOP Publishing |
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CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
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dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
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