Discovery of a very weak magnetic field on the Am star Alhena
International audience Alhena (γ Gem) was observed in the frame of the BRIght Target Explorer spectropolarimetric survey, which gathers high resolution, high signal-to-noise, high sensitivity, spectropolarimetric observations of all stars brighter than V = 4 to combine seismic and spectropolarimetri...
Published in: | Monthly Notices of the Royal Astronomical Society: Letters |
---|---|
Main Authors: | , , |
Other Authors: | , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
HAL CCSD
2016
|
Subjects: | |
Online Access: | https://hal.sorbonne-universite.fr/hal-01331660 https://doi.org/10.1093/mnrasl/slw050 |
id |
ftsorbonneuniv:oai:HAL:hal-01331660v1 |
---|---|
record_format |
openpolar |
spelling |
ftsorbonneuniv:oai:HAL:hal-01331660v1 2024-05-19T07:50:08+00:00 Discovery of a very weak magnetic field on the Am star Alhena Blazère, Aurore Neiner, C. Petit, P. Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA) Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS) Institut de recherche en astrophysique et planétologie (IRAP) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) 2016 https://hal.sorbonne-universite.fr/hal-01331660 https://doi.org/10.1093/mnrasl/slw050 en eng HAL CCSD Wiley-Blackwell info:eu-repo/semantics/altIdentifier/arxiv/1603.06486 info:eu-repo/semantics/altIdentifier/doi/10.1093/mnrasl/slw050 hal-01331660 https://hal.sorbonne-universite.fr/hal-01331660 ARXIV: 1603.06486 BIBCODE: 2016MNRAS.459L.81B doi:10.1093/mnrasl/slw050 ISSN: 1745-3925 EISSN: 1745-3933 Monthly Notice- Royal Astronomical Society -Letters- https://hal.sorbonne-universite.fr/hal-01331660 Monthly Notice- Royal Astronomical Society -Letters-, 2016, 459 (1), pp.L81-L84. ⟨10.1093/mnrasl/slw050⟩ stars: chemically peculiar stars: individual: γ Gem stars: magnetic field [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] info:eu-repo/semantics/article Journal articles 2016 ftsorbonneuniv https://doi.org/10.1093/mnrasl/slw050 2024-04-25T04:14:46Z International audience Alhena (γ Gem) was observed in the frame of the BRIght Target Explorer spectropolarimetric survey, which gathers high resolution, high signal-to-noise, high sensitivity, spectropolarimetric observations of all stars brighter than V = 4 to combine seismic and spectropolarimetric studies of bright stars. We present here the discovery of a very weak magnetic field on the Am star Alhena, thanks to very high signal-to-noise spectropolarimetric data obtained with Narval at Télescope Bernard Lyot. All previously studied Am stars show the presence of ultraweak (sub-Gauss) fields with Zeeman signatures with an unexpected prominent positive lobe. However, Alhena presents a slightly stronger (but still very weak, only a few Gauss) field with normal Zeeman signatures with a positive and negative lobe, as found in stronger field (hundreds or thousands of Gauss) stars. It is the first detection of a normal magnetic signature in an Am star. Alhena is thus a very interesting object, which might provide the clue to understanding the peculiar shapes of the magnetic signatures of the other Am stars. Article in Journal/Newspaper narval narval HAL Sorbonne Université Monthly Notices of the Royal Astronomical Society: Letters 459 1 L81 L84 |
institution |
Open Polar |
collection |
HAL Sorbonne Université |
op_collection_id |
ftsorbonneuniv |
language |
English |
topic |
stars: chemically peculiar stars: individual: γ Gem stars: magnetic field [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
spellingShingle |
stars: chemically peculiar stars: individual: γ Gem stars: magnetic field [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] Blazère, Aurore Neiner, C. Petit, P. Discovery of a very weak magnetic field on the Am star Alhena |
topic_facet |
stars: chemically peculiar stars: individual: γ Gem stars: magnetic field [PHYS.ASTR]Physics [physics]/Astrophysics [astro-ph] |
description |
International audience Alhena (γ Gem) was observed in the frame of the BRIght Target Explorer spectropolarimetric survey, which gathers high resolution, high signal-to-noise, high sensitivity, spectropolarimetric observations of all stars brighter than V = 4 to combine seismic and spectropolarimetric studies of bright stars. We present here the discovery of a very weak magnetic field on the Am star Alhena, thanks to very high signal-to-noise spectropolarimetric data obtained with Narval at Télescope Bernard Lyot. All previously studied Am stars show the presence of ultraweak (sub-Gauss) fields with Zeeman signatures with an unexpected prominent positive lobe. However, Alhena presents a slightly stronger (but still very weak, only a few Gauss) field with normal Zeeman signatures with a positive and negative lobe, as found in stronger field (hundreds or thousands of Gauss) stars. It is the first detection of a normal magnetic signature in an Am star. Alhena is thus a very interesting object, which might provide the clue to understanding the peculiar shapes of the magnetic signatures of the other Am stars. |
author2 |
Laboratoire d'études spatiales et d'instrumentation en astrophysique (LESIA) Université Pierre et Marie Curie - Paris 6 (UPMC)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire de Paris Université Paris Sciences et Lettres (PSL)-Université Paris Sciences et Lettres (PSL)-Université Paris Diderot - Paris 7 (UPD7)-Centre National de la Recherche Scientifique (CNRS) Institut de recherche en astrophysique et planétologie (IRAP) Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP) Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3) Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS) |
format |
Article in Journal/Newspaper |
author |
Blazère, Aurore Neiner, C. Petit, P. |
author_facet |
Blazère, Aurore Neiner, C. Petit, P. |
author_sort |
Blazère, Aurore |
title |
Discovery of a very weak magnetic field on the Am star Alhena |
title_short |
Discovery of a very weak magnetic field on the Am star Alhena |
title_full |
Discovery of a very weak magnetic field on the Am star Alhena |
title_fullStr |
Discovery of a very weak magnetic field on the Am star Alhena |
title_full_unstemmed |
Discovery of a very weak magnetic field on the Am star Alhena |
title_sort |
discovery of a very weak magnetic field on the am star alhena |
publisher |
HAL CCSD |
publishDate |
2016 |
url |
https://hal.sorbonne-universite.fr/hal-01331660 https://doi.org/10.1093/mnrasl/slw050 |
genre |
narval narval |
genre_facet |
narval narval |
op_source |
ISSN: 1745-3925 EISSN: 1745-3933 Monthly Notice- Royal Astronomical Society -Letters- https://hal.sorbonne-universite.fr/hal-01331660 Monthly Notice- Royal Astronomical Society -Letters-, 2016, 459 (1), pp.L81-L84. ⟨10.1093/mnrasl/slw050⟩ |
op_relation |
info:eu-repo/semantics/altIdentifier/arxiv/1603.06486 info:eu-repo/semantics/altIdentifier/doi/10.1093/mnrasl/slw050 hal-01331660 https://hal.sorbonne-universite.fr/hal-01331660 ARXIV: 1603.06486 BIBCODE: 2016MNRAS.459L.81B doi:10.1093/mnrasl/slw050 |
op_doi |
https://doi.org/10.1093/mnrasl/slw050 |
container_title |
Monthly Notices of the Royal Astronomical Society: Letters |
container_volume |
459 |
container_issue |
1 |
container_start_page |
L81 |
op_container_end_page |
L84 |
_version_ |
1799468728985845760 |