J/A+A/409/275ivo://CDS.VizieR/J/A+A/409/275doi:10.26093/cds/vizier.34090275CDSNeiner C.Hubert A.M.Fremat Y.Floquet M.Jankov S.Preuss O.,Henrichs H.F.Zorec J.2003-11-13T20:22:13Z2003-11-13T21:22:08ZCDS support team

CDS, Observatoire de Strasbourg, 11 rue de l'Universite, F-67000 Strasbourg, France

cds-question@unistra.frbe-starsmagnetic-fieldsOmega Ori is a B2IIIe star for which rotational modulation and non-radial pulsations (NRP) have been recently investigated from two independent observational campaigns in 1998 and 1999. Putting the data of these 2 campaigns together, and adding data obtained in 2001, we search for multiperiodicity in the line profile variations and evidence for outbursts. From new spectropolarimetric data obtained at the Telescope Bernard Lyot (TBL, Pic du Midi, France) in 2001 we also measure the Stokes V parameter in the polarised light. We find evidence for the presence of a weak magnetic field in Omega Ori sinusoidally varying with a period of 1.29d. The equivalent widths (EW) of the wind sensitive UV resonance lines also show a variation with the same period, which we identify as the rotational period of the star. We propose an oblique rotator model and derive B_pol_=530+/-230G to explain the observations. Moreover, we carry out an abundance analysis and find the star to be N-enriched, a property which is shared with other magnetic stars. We propose Omega Ori as the first known classical Be star hosting a magnetic field.2003A&A...409..275Nhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/409/275CatalogResearchIsServedByTAP VizieR generic servicerelated-toJ/A+A/368/912 : Be stars polarization and rotational velocities (Yudin, 2001)J/A+AS/111/399 : Polarization variability in Herbig Ae/Be stars (Jain+, 1995)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/409/275https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/409/275http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/409/275https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/409/275https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/409/275http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/409/275GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapdefaultJ/A+A/409/275/table7Longitudinal magnetic field measurementsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNexpNumber of the exposuremeta.numberintHJDHeliocentric Julian Date at mid-exposuredtime.epochdoublePhase[0/1[ Phase with f=0.78c/d and HJD_0_=2452265.1time.phasefloatBLongitudinal field (in Gauss)1e-07Tphys.magFieldinte_Brms uncertainty on B1e-07Tstat.errorintNNull polarisation (1)1e-07Tphys.magFieldinte_Nrms uncertainty on N1e-07Tstat.errorint