Magnetospheric accretion on the T Tauri star BP Tauri
International audience From observations collected with the ESPaDOnS and NARVAL spectropolarimeters, we report the detection of Zeeman signatures on the classical T Tauri star (cTTS) BP Tau. Circular polarization signatures in photospheric lines and in narrow emission lines tracing magnetospheric ac...
Published in: | Monthly Notices of the Royal Astronomical Society |
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ftccsdartic:oai:HAL:hal-00398497v1 2023-05-15T18:50:51+02:00 Magnetospheric accretion on the T Tauri star BP Tauri Donati, J.-F. Jardine, M. M. Gregory, S. G. Petit, P. Paletou, F. Bouvier, J. Dougados, C. Ménard, F. Cameron, A. C. Harries, T. J. Hussain, G. A. J. Unruh, Y. Morin, J. Marsden, S. C. Manset, N. Aurière, M. Catala, C. Alecian, E. Laboratoire d'Astrophysique de Grenoble (LAOG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) 2008 https://hal.archives-ouvertes.fr/hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497/document https://hal.archives-ouvertes.fr/hal-00398497/file/mnras0386-1234.pdf https://doi.org/10.1111/j.1365-2966.2008.13111.x en eng HAL CCSD Oxford University Press (OUP): Policy P - Oxford Open Option A info:eu-repo/semantics/altIdentifier/doi/10.1111/j.1365-2966.2008.13111.x hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497/document https://hal.archives-ouvertes.fr/hal-00398497/file/mnras0386-1234.pdf doi:10.1111/j.1365-2966.2008.13111.x info:eu-repo/semantics/OpenAccess ISSN: 0035-8711 EISSN: 1365-2966 Monthly Notices of the Royal Astronomical Society https://hal.archives-ouvertes.fr/hal-00398497 Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2008, 386, pp.1234. ⟨10.1111/j.1365-2966.2008.13111.x⟩ [SDU]Sciences of the Universe [physics] info:eu-repo/semantics/article Journal articles 2008 ftccsdartic https://doi.org/10.1111/j.1365-2966.2008.13111.x 2021-11-21T00:28:52Z International audience From observations collected with the ESPaDOnS and NARVAL spectropolarimeters, we report the detection of Zeeman signatures on the classical T Tauri star (cTTS) BP Tau. Circular polarization signatures in photospheric lines and in narrow emission lines tracing magnetospheric accretion are monitored throughout most of the rotation cycle of BP Tau at two different epochs in 2006. We observe that rotational modulation dominates the temporal variations of both unpolarized and circularly polarized spectral proxies tracing the photosphere and the footpoints of accretion funnels. From the complete data sets at each epoch, we reconstruct the large-scale magnetic topology and the location of accretion spots at the surface of BP Tau using tomographic imaging. We find that the field of BP Tau involves a 1.2 kG dipole and 1.6 kG octupole, both slightly tilted with respect to the rotation axis. Accretion spots coincide with the two main magnetic poles at high latitudes and overlap with dark photospheric spots; they cover about 2 per cent of the stellar surface. The strong mainly axisymmetric poloidal field of BP Tau is very reminiscent of magnetic topologies of fully convective dwarfs. It suggests that magnetic fields of fully convective cTTSs such as BP Tau are likely not fossil remants, but rather result from vigorous dynamo action operating within the bulk of their convective zones. Preliminary modelling suggests that the magnetosphere of BP Tau extends to distances of at least 4R* to ensure that accretion spots are located at high latitudes, and is not blown open close to the surface by a putative stellar wind. It apparently succeeds in coupling to the accretion disc as far out as the corotation radius, and could possibly explain the slow rotation of BP Tau. Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT) and at the Télescope Bernard Lyot (TBL). CFHT is operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre ... Article in Journal/Newspaper narval narval Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) Canada Monthly Notices of the Royal Astronomical Society 386 3 1234 1251 |
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Archive ouverte HAL (Hyper Article en Ligne, CCSD - Centre pour la Communication Scientifique Directe) |
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ftccsdartic |
language |
English |
topic |
[SDU]Sciences of the Universe [physics] |
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[SDU]Sciences of the Universe [physics] Donati, J.-F. Jardine, M. M. Gregory, S. G. Petit, P. Paletou, F. Bouvier, J. Dougados, C. Ménard, F. Cameron, A. C. Harries, T. J. Hussain, G. A. J. Unruh, Y. Morin, J. Marsden, S. C. Manset, N. Aurière, M. Catala, C. Alecian, E. Magnetospheric accretion on the T Tauri star BP Tauri |
topic_facet |
[SDU]Sciences of the Universe [physics] |
description |
International audience From observations collected with the ESPaDOnS and NARVAL spectropolarimeters, we report the detection of Zeeman signatures on the classical T Tauri star (cTTS) BP Tau. Circular polarization signatures in photospheric lines and in narrow emission lines tracing magnetospheric accretion are monitored throughout most of the rotation cycle of BP Tau at two different epochs in 2006. We observe that rotational modulation dominates the temporal variations of both unpolarized and circularly polarized spectral proxies tracing the photosphere and the footpoints of accretion funnels. From the complete data sets at each epoch, we reconstruct the large-scale magnetic topology and the location of accretion spots at the surface of BP Tau using tomographic imaging. We find that the field of BP Tau involves a 1.2 kG dipole and 1.6 kG octupole, both slightly tilted with respect to the rotation axis. Accretion spots coincide with the two main magnetic poles at high latitudes and overlap with dark photospheric spots; they cover about 2 per cent of the stellar surface. The strong mainly axisymmetric poloidal field of BP Tau is very reminiscent of magnetic topologies of fully convective dwarfs. It suggests that magnetic fields of fully convective cTTSs such as BP Tau are likely not fossil remants, but rather result from vigorous dynamo action operating within the bulk of their convective zones. Preliminary modelling suggests that the magnetosphere of BP Tau extends to distances of at least 4R* to ensure that accretion spots are located at high latitudes, and is not blown open close to the surface by a putative stellar wind. It apparently succeeds in coupling to the accretion disc as far out as the corotation radius, and could possibly explain the slow rotation of BP Tau. Based on observations obtained at the Canada-France-Hawaii Telescope (CFHT) and at the Télescope Bernard Lyot (TBL). CFHT is operated by the National Research Council of Canada, the Institut National des Sciences de l'Univers of the Centre ... |
author2 |
Laboratoire d'Astrophysique de Grenoble (LAOG) Université Joseph Fourier - Grenoble 1 (UJF)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Donati, J.-F. Jardine, M. M. Gregory, S. G. Petit, P. Paletou, F. Bouvier, J. Dougados, C. Ménard, F. Cameron, A. C. Harries, T. J. Hussain, G. A. J. Unruh, Y. Morin, J. Marsden, S. C. Manset, N. Aurière, M. Catala, C. Alecian, E. |
author_facet |
Donati, J.-F. Jardine, M. M. Gregory, S. G. Petit, P. Paletou, F. Bouvier, J. Dougados, C. Ménard, F. Cameron, A. C. Harries, T. J. Hussain, G. A. J. Unruh, Y. Morin, J. Marsden, S. C. Manset, N. Aurière, M. Catala, C. Alecian, E. |
author_sort |
Donati, J.-F. |
title |
Magnetospheric accretion on the T Tauri star BP Tauri |
title_short |
Magnetospheric accretion on the T Tauri star BP Tauri |
title_full |
Magnetospheric accretion on the T Tauri star BP Tauri |
title_fullStr |
Magnetospheric accretion on the T Tauri star BP Tauri |
title_full_unstemmed |
Magnetospheric accretion on the T Tauri star BP Tauri |
title_sort |
magnetospheric accretion on the t tauri star bp tauri |
publisher |
HAL CCSD |
publishDate |
2008 |
url |
https://hal.archives-ouvertes.fr/hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497/document https://hal.archives-ouvertes.fr/hal-00398497/file/mnras0386-1234.pdf https://doi.org/10.1111/j.1365-2966.2008.13111.x |
geographic |
Canada |
geographic_facet |
Canada |
genre |
narval narval |
genre_facet |
narval narval |
op_source |
ISSN: 0035-8711 EISSN: 1365-2966 Monthly Notices of the Royal Astronomical Society https://hal.archives-ouvertes.fr/hal-00398497 Monthly Notices of the Royal Astronomical Society, Oxford University Press (OUP): Policy P - Oxford Open Option A, 2008, 386, pp.1234. ⟨10.1111/j.1365-2966.2008.13111.x⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/doi/10.1111/j.1365-2966.2008.13111.x hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497 https://hal.archives-ouvertes.fr/hal-00398497/document https://hal.archives-ouvertes.fr/hal-00398497/file/mnras0386-1234.pdf doi:10.1111/j.1365-2966.2008.13111.x |
op_rights |
info:eu-repo/semantics/OpenAccess |
op_doi |
https://doi.org/10.1111/j.1365-2966.2008.13111.x |
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Monthly Notices of the Royal Astronomical Society |
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386 |
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