14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap
Context. 14 Ceti is a subgiant star of F spectral class that displays variations in the S-index of its Ca II H & K lines and an X-ray emission that is stronger than the mean observed for its spectral class, which may be due to some magnetic activity. Aims. We attempt to Zeeman-detect and study t...
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ftunivbruxelles:oai:dipot.ulb.ac.be:2013/145858 2023-05-15T18:50:52+02:00 14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap Aurière, Michel Konstantinova-Antova, Renada Petit, P. Charbonnel, Corinne Van Eck, Sophie Donati, Jean François Lignières, F. Roudier, Th 2012-07 1 full-text file(s): application/pdf http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/145858 https://dipot.ulb.ac.be/dspace/bitstream/2013/145858/3/doi_129713.pdf en eng uri/info:doi/10.1051/0004-6361/201219324 uri/info:scp/84863668689 https://dipot.ulb.ac.be/dspace/bitstream/2013/145858/3/doi_129713.pdf http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/145858 1 full-text file(s): info:eu-repo/semantics/restrictedAccess Astronomy & Astrophysics, 543 Astrophysique stars: individual: 14 Ceti stars: magnetic field stars: late-type info:eu-repo/semantics/article info:ulb-repo/semantics/articlePeerReview info:ulb-repo/semantics/openurl/article 2012 ftunivbruxelles 2022-06-12T21:23:44Z Context. 14 Ceti is a subgiant star of F spectral class that displays variations in the S-index of its Ca II H & K lines and an X-ray emission that is stronger than the mean observed for its spectral class, which may be due to some magnetic activity. Aims. We attempt to Zeeman-detect and study the magnetic field of 14 Ceti and to infer its origin. Methods. We used the spectropolarimeter Narval at the Telescope Bernard Lyot, Pic du Midi Observatory, and the least squares deconvolution method to create high signal-to-noise ratio Stokes V profiles. We derived the surface-averaged longitudinal magnetic field B l. We also measured the S-index, and the radial velocity for each observation. Results. 14 Ceti is Zeeman-detected for the 30 observed dates spanning from August 2007 to January 2012. The average longitudinal magnetic field does not reverse its sign, reaches about-35 G, and shows some month-long-timescale variations in our 2008 and 2011-2012 observations. The S-index follows the same long-term trend as B l. 14 Ceti is confirmed as a single star without H-K emission cores. The strength of the observed surface magnetic field of 14 Ceti is one order of magnitude greater than the observed one for late F main-sequence stars, and is comparable to the values measured in the active late F pre-main-sequence star HR 1817. On the other hand, taking into account the post-main-sequence evolution of an Ap star, an oblique rotator model can explain the strength of the magnetic field of 14 Ceti. The variations with a timescale of months observed for both the B l and S-index could be due to the rotation. Conclusions. The most probable scenario to explain our observations appears to be that 14 Ceti is the descendant of a cool Ap star. © 2012 ESO. SCOPUS: ar.j info:eu-repo/semantics/published Article in Journal/Newspaper narval narval DI-fusion : dépôt institutionnel de l'Université libre de Bruxelles (ULB) |
institution |
Open Polar |
collection |
DI-fusion : dépôt institutionnel de l'Université libre de Bruxelles (ULB) |
op_collection_id |
ftunivbruxelles |
language |
English |
topic |
Astrophysique stars: individual: 14 Ceti stars: magnetic field stars: late-type |
spellingShingle |
Astrophysique stars: individual: 14 Ceti stars: magnetic field stars: late-type Aurière, Michel Konstantinova-Antova, Renada Petit, P. Charbonnel, Corinne Van Eck, Sophie Donati, Jean François Lignières, F. Roudier, Th 14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
topic_facet |
Astrophysique stars: individual: 14 Ceti stars: magnetic field stars: late-type |
description |
Context. 14 Ceti is a subgiant star of F spectral class that displays variations in the S-index of its Ca II H & K lines and an X-ray emission that is stronger than the mean observed for its spectral class, which may be due to some magnetic activity. Aims. We attempt to Zeeman-detect and study the magnetic field of 14 Ceti and to infer its origin. Methods. We used the spectropolarimeter Narval at the Telescope Bernard Lyot, Pic du Midi Observatory, and the least squares deconvolution method to create high signal-to-noise ratio Stokes V profiles. We derived the surface-averaged longitudinal magnetic field B l. We also measured the S-index, and the radial velocity for each observation. Results. 14 Ceti is Zeeman-detected for the 30 observed dates spanning from August 2007 to January 2012. The average longitudinal magnetic field does not reverse its sign, reaches about-35 G, and shows some month-long-timescale variations in our 2008 and 2011-2012 observations. The S-index follows the same long-term trend as B l. 14 Ceti is confirmed as a single star without H-K emission cores. The strength of the observed surface magnetic field of 14 Ceti is one order of magnitude greater than the observed one for late F main-sequence stars, and is comparable to the values measured in the active late F pre-main-sequence star HR 1817. On the other hand, taking into account the post-main-sequence evolution of an Ap star, an oblique rotator model can explain the strength of the magnetic field of 14 Ceti. The variations with a timescale of months observed for both the B l and S-index could be due to the rotation. Conclusions. The most probable scenario to explain our observations appears to be that 14 Ceti is the descendant of a cool Ap star. © 2012 ESO. SCOPUS: ar.j info:eu-repo/semantics/published |
format |
Article in Journal/Newspaper |
author |
Aurière, Michel Konstantinova-Antova, Renada Petit, P. Charbonnel, Corinne Van Eck, Sophie Donati, Jean François Lignières, F. Roudier, Th |
author_facet |
Aurière, Michel Konstantinova-Antova, Renada Petit, P. Charbonnel, Corinne Van Eck, Sophie Donati, Jean François Lignières, F. Roudier, Th |
author_sort |
Aurière, Michel |
title |
14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
title_short |
14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
title_full |
14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
title_fullStr |
14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
title_full_unstemmed |
14 Ceti: a probable Ap-star-descendant entering the Hertzsprung gap |
title_sort |
14 ceti: a probable ap-star-descendant entering the hertzsprung gap |
publishDate |
2012 |
url |
http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/145858 https://dipot.ulb.ac.be/dspace/bitstream/2013/145858/3/doi_129713.pdf |
genre |
narval narval |
genre_facet |
narval narval |
op_source |
Astronomy & Astrophysics, 543 |
op_relation |
uri/info:doi/10.1051/0004-6361/201219324 uri/info:scp/84863668689 https://dipot.ulb.ac.be/dspace/bitstream/2013/145858/3/doi_129713.pdf http://hdl.handle.net/2013/ULB-DIPOT:oai:dipot.ulb.ac.be:2013/145858 |
op_rights |
1 full-text file(s): info:eu-repo/semantics/restrictedAccess |
_version_ |
1766244619237982208 |