J/MNRAS/390/567ivo://CDS.VizieR/J/MNRAS/390/567doi:10.26093/cds/vizier.73900567CDSMorin J.Donati J.-F.Petit P.Delfosse X.Forveille T.Albert L.,Auriere M.Cabanac R.Dintrans B.Fares R.Gastine T.Jardine M.M.,Lignieres F.Paletou F.Ramirez Velez J.C.Theado S.2024-07-07T20:17:10Z2010-07-05T15:47:48ZCDS support team

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

cds-question@unistra.frm-starsmagnetic-fieldsWe present in this paper, the first results of a spectropolarimetric analysis of a small sample (~20) of active stars ranging from spectral type M0 to M8, which are either fully convective or possess a very small radiative core. This study aims at providing new constraints on dynamo processes in fully convective stars. This paper focuses on ve stars of spectral type ~M4, i.e. with masses close to the full convection threshold (0.35M_{sun}_), and with short rotational periods. Tomographic imaging techniques allow us to reconstruct the surface magnetic topologies from the rotationally modulated time-series of circularly polarized profiles. We find that all stars host mainly axisymmetric large-scale poloidal fields. Three stars were observed at two different epochs separated by 1yr; we find the magnetic topologies to be globally stable on this time-scale. We also provide an accurate estimation of the rotational period of all stars, thus allowing us to start studying how rotation impacts the large-scale magnetic field.2008MNRAS.390..567Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/390/567CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toB/cfht : Log of CFHT Exposures (CADC, 1979-)I/239 : The Hipparcos and Tycho Catalogues (ESA 1997)II/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)III/198 : Palomar/MSU nearby star spectroscopic survey (Hawley+ 1997)J/A+A/331/581 : Rotation and activity in field M dwarfs (Delfosse+ 1998)J/A+A/417/651 : NEXXUS ROSAT survey of coronal X-ray (Schmitt+ 2004)J/MNRAS/390/545 : Magnetic topologies of early M dwarfs (Donati+ 2008)J/MNRAS/407/2269 : Magnetic topologies of late M dwarfs (Morin+, 2010)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/390/567https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/390/567http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/390/567https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/390/567https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/390/567http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/390/567GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/390/567/table1 (Fundamental parameters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/390/567/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/390/567/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/390/567/table1?GETtext/xml+votable180.050000true154.901166719.87002780.0055555555555555566/4444 13451 13743 20071 22289https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/390/567?format=asciidefaultJ/MNRAS/390/567/table1Fundamental parametersl_RadLimit flag on error on Rad (10)meta.code.errorcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameDesignations of the starmeta.idcharprimarySNameGJ namemeta.idcharRAJ2000Simbad Hour of Right Ascension (J2000.0)pos.eq.ra;meta.mainDEJ2000Simbad Degree of Declination (J2000.0)pos.eq.dec;meta.mainSpTMK spectral type (1)src.spTypecharMassMass of the star (2)solMassphys.massfloatl_MassLimit flag on e_Mass (2)meta.code.error;phys.masschare_MassFormal 1-{sigma} error bar on Mass (2)solMassstat.error;phys.massfloatLbolLogarithmic bolometric luminosity (3)log(1e-07W)phys.luminosityfloatLX/LbolRatio of X-ray to bolometric luminosity (4)phys.luminosity;arith.ratiofloatvsiniEquatorial rotational velocity along line of sight (5)km/sphys.veloc.rotatfloatr_vsini[a] a: vsini from Reiners & Basri, 2007ApJ...656.1121Rmeta.refcharl_BfLimit flag on Bf (6)meta.code.errorcharBf? Magnetic flux (6)0.1Tphot.fluxfloatnullabler_Bf[a] a: Bf from Reiners & Basri, 2007ApJ...656.1121Rmeta.ref;pos.framecharProtRotation period (7)dtime.perioddoublee_Prot3-{sigma} error bar on Prot (7)dstat.errordoubletaucEmpirical convective turnover time (8)dtime.epochintRoEmpirical Rossby number (8)stat.paramfloatRsini?Stellar radius times sini (9)solRadphys.size.radiusfloatnullablel_RsiniLimit flag on error on Rsini (9)meta.code.errorchare_RsiniFormal 1-{sigma} error bar on Rsini (9)solRadstat.errorfloatRadTheoretical stellar radius (10)solRadphys.size.radiusfloate_RadFormal 1-{sigma} error bar on Rad (10)solRadstat.errorfloatiInclination of the stellar rotation axis (11)degphys.angSizeintTab? Number of the corresponding table with observations in the papermeta.numberintnullableSimbadSimbad column added by the CDScharJ/MNRAS/390/567/tablesDates, magnetic field and radial velocity (tables 2-6 of the paper)recnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNameDesignation of the starmeta.id;phys.atmol.configurationcharObsUT date of observationstime.epoch;obsnullableHJDUT heliocentric Julian date of observationdtime.epochdoubleSiteObservation site (CFHT or TBL = Telescope Bernard Lyot)meta.id;instr.obstycharTexpExposure time (NxNNNN.N in s)stime.duration;obs.exposurecharS/NSignal to noise ratiostat.snrintsigmarms noise level in polarisation profile (4)instr.det.noisefloatBlLongitudinal magnetic field (Gauss) (1)0.0001Tphys.magFieldfloate_Blrms uncertainty on Bl (1)0.0001Tstat.errorfloatERotation cycle (3)meta.number;time.periodfloatRVRadial velocity (2)km/sphys.veloc;pos.heliocentricfloat