Article (Scientific journals)
Detecting and modelling the magnetic field of the β Cephei star V 2052 Ophiuchi
Neiner, C.; Alecian, E.; Briquet, Maryline et al.
2012In Astronomy and Astrophysics, 537, p. 148
Peer Reviewed verified by ORBi
 

Files


Full Text
aa17941-11.pdf
Publisher postprint (1.1 MB)
Download

All documents in ORBi are protected by a user license.

Send to



Details



Keywords :
stars: magnetic field; stars: early-type; stars: individual: V 2052 Oph; starspots
Abstract :
[en] <BR /> Aims: Following the indirect detection of a magnetic field in the β Cephei star <ASTROBJ>V 2052 Oph</ASTROBJ> by Neiner and collaborators in 2003 with the Musicos spectropolarimeter, we remeasured the magnetic field of this star to attempt to directly confirm the detection of a magnetic field and study its configuration in greater detail. <BR /> Methods: We used the Narval spectropolarimeter installed at TBL (Pic du Midi, France), which is about 20 times more efficient than the Musicos spectropolarimeter. We applied the least-squares deconvolution (LSD) technique to various groups of lines to measure the circular polarisation of the light coming from <ASTROBJ>V 2052 Oph</ASTROBJ>. We synthesized the measured Stokes V profiles with a centred and off-centred dipole model. <BR /> Results: For the first time, we clearly detect the Zeeman signature in the Stokes V profiles of <ASTROBJ>V 2052 Oph</ASTROBJ> and thus directly prove the presence of a magnetic field in this star. The modulation with the rotation period is also confirmed and reflects an oblique dipole field. Thanks to the small error bars on the measurements, we are able to study the behaviour of different groups of lines and the centring of the dipole in the star. We find that the dipole is most likely off-centred along the magnetic axis and that He spots are present at the surface next to the magnetic axis. <BR /> Conclusions: We conclude that <ASTROBJ>V 2052 Oph</ASTROBJ> is a magnetic He-strong β Cep star, with a dipole field, probably off-centred, with B[SUB]pol[/SUB] ~ 400 G and He patches close to the magnetic poles. Based on observations obtained with the Narval spectropolarimeter at the Télescope Bernard Lyot, Observatoire du Pic du Midi, France.
Disciplines :
Space science, astronomy & astrophysics
Author, co-author :
Neiner, C.;  LESIA, Observatoire de Paris, CNRS UMR 8109, UPMC, Université Paris Diderot, 5 place Jules Janssen, 92190, Meudon, France
Alecian, E.;  LESIA, Observatoire de Paris, CNRS UMR 8109, UPMC, Université Paris Diderot, 5 place Jules Janssen, 92190, Meudon, France
Briquet, Maryline ;  Université de Liège - ULiège > Département d'astrophys., géophysique et océanographie (AGO) > Astrophysique stellaire théorique et astérosismologie
Floquet, M.;  GEPI, Observatoire de Paris, CNRS UMR 8111, Université Paris Diderot, 5 place Jules Janssen, 92190, Meudon, France
Frémat, Y.;  Royal Observatory of Belgium, 3 avenue circulaire, 1180, Brussels, Belgium
Martayan, C.;  ESO, Alonso de Cordova 3107, Vitacura, Casilla 19001, Santiago 19, Chile
Thizy, O.;  Shelyak Instruments, Les Roussets, 38420, Revel, France
Language :
English
Title :
Detecting and modelling the magnetic field of the β Cephei star V 2052 Ophiuchi
Publication date :
01 January 2012
Journal title :
Astronomy and Astrophysics
ISSN :
0004-6361
eISSN :
1432-0746
Publisher :
EDP Sciences, Les Ulis, France
Volume :
537
Pages :
148
Peer reviewed :
Peer Reviewed verified by ORBi
Available on ORBi :
since 31 January 2012

Statistics


Number of views
49 (5 by ULiège)
Number of downloads
62 (0 by ULiège)

Scopus citations®
 
34
Scopus citations®
without self-citations
8
OpenCitations
 
31

Bibliography


Similar publications



Contact ORBi