J/MNRAS/498/2456ivo://CDS.VizieR/J/MNRAS/498/2456doi:10.26093/cds/vizier/bg-fj-2crCDSSikora J.Wade G.A.Rowe J.2026-08-03T07:30:07Z2023-11-03T10:34:41ZCDS support team

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

cds-question@unistra.frearly-type-starsvariable-starsmilky-way-galaxyeffective-temperaturestellar-radiistellar-massesradial-velocityphotometryspectroscopyvisible-astronomyHigh-precision space-based photometry obtained by the Kepler and TESS missions has revealed evidence of rotational modulation associated with main-sequence (MS) A- and late B-type stars. Generally, such variability in these objects is attributed to inhomogeneous surface structures (e.g. chemical spots), which are typically linked to strong magnetic fields (B>~100G) visible at the surface. It has been reported that ~44 per cent of all A-type stars observed during the Kepler mission exhibit rotationally modulated light curves. This is surprising considering that =<10 per cent of all MS A-type stars are known to be strongly magnetic (i.e. they are Ap/Bp stars). We present a spectroscopic monitoring survey of 44 A- and late B-type stars reported to exhibit rotational modulation in their Kepler light curves. The primary goal of this survey is to test the hypothesis that the variability is rotational modulation by comparing each star's rotational broadening (vsini) with the equatorial velocities (v_eq_) inferred from the photometric periods. We searched for chemical peculiarities and binary companions in order to provide insight into the origin of the apparent rotational modulation. We find that 14 stars in our sample have vsini>v_eq_ and/or have low-mass companions that may contribute to or be responsible for the observed variability. Our results suggest that more than 10 per cent of all MS A- and late B-type stars may exhibit inhomogeneous surface structures; however, the incidence rate is likely =<30 per cent.2020MNRAS.498.2456Shttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/498/2456CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/498/2456https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/498/2456http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/498/2456https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/498/2456https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/498/2456http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/498/2456GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/498/2456/spparam (Various parameters derived from the spectroscopic observations of the 44 stars in our sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/498/2456/spparam?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/498/2456/spparam?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/498/2456/spparam?GETtext/xml+votable180.050000true291.155356437.13093940.0055555555555555566/14578-14579 14583 14587 14589 14744 14754-14755 14759 14761-14762 14765 14768 14770 14772-14773 14777 14779 14825 14917 14921 14925-14926 14929 14948 14962-14964 14967 15105 15108-15109 15120 15122 15129 15132 15135 15141 15149-15150https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/498/2456?format=asciiOpticaldefaultJ/MNRAS/498/2456/spparamVarious parameters derived from the spectroscopic observations of the 44 stars in our samplee_TeffError on TeffKstat.error;phys.temperature.effectiveintSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintMoreLink to tables rv1, rv2 and rv3meta.ref.urlcharKICKIC identifiermeta.id;meta.mainintprimaryTeffEffective temperatureKphys.temperature.effectiveintl_logg[=< ] Limit flag on loggmeta.code.errorcharloggSurface gravitylog(cm.s**-2)phys.gravityfloate_logg? Error on logglog(cm.s**-2)stat.errorfloatnullablel_[M/H][=<> ] Limit flag on [M/H]meta.code.error;phys.abundchar[M/H]Metallicityphys.abund.Zfloate_[M/H]? Error on [M/H]stat.error;phys.abundfloatnullablevsiniProjected rotational broadeningkm/sphys.veloc.rotatinte_vsiniError on vsinikm/sstat.error;phys.veloc.rotatintl_xi[=< ] Limit flag on vtmeta.code.errorcharxi? Microturbulence broadeningkm/sphys.veloc.microTurbfloatnullablee_xi? Error on xikm/sstat.errorfloatnullableRV1indicates data in rv1.dat filemeta.codecharRV2indicates data in rv2.dat filemeta.codecharRV3indicates data in rv3.dat filemeta.codechar_RARight Ascension (J2000) from SIMBAD (not part of the original data)degpos.eq.ra;meta.main_DEDeclination (J2000) from SIMBAD (not part of the original data)degpos.eq.dec;meta.mainJ/MNRAS/498/2456/hrdparamVarious fundamental parameters associated with 43 of the 44 stars in our with known distancesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC identifiermeta.id;meta.mainintE(B-V)Reddeningmagphot.color.excessfloatlogTeffLogarithm of the effective temperaturelog(K)phys.temperature.effectivefloate_logTeffError on logTefflog(K)stat.error;phys.temperature.effectivefloatlogLLogarithm of the star luminositylog(solLum)phys.luminosityfloate_logLError on logglog(solLum)stat.errorfloatRStar radiussolRadphys.size.radiusfloate_RError on RsolRadstat.errorfloatMassStar masssolMassphys.massfloate_MassLower error on MasssolMassstat.error;phys.massfloatE_MassError on MasssolMassstat.error;stat.maxfloatlogtLogarithm of the absolute agelog(Gyr)time.agefloate_logtLower error on logtlog(Gyr)stat.errorfloatE_logtUpper error on logtlog(Gyr)stat.error;stat.maxfloattauFractional main sequence agetime.agefloate_tauLower error on taustat.errorfloatE_tauUpper error on taustat.error;stat.maxfloatJ/MNRAS/498/2456/rv1Radial velocities for those targets with one stellar component that was identified in the LSD profilesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC identifiermeta.id;meta.mainintHJDHeliocentric Julian Date (HJD-2458000)dtime.epochfloatRVARadial velocity of the primary component derived from the spectral fitskm/sphys.veloc;pos.heliocentricfloate_RVAError on RVAkm/sstat.errorfloatRVALSD? Radial velocity of the primary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloatnullablee_RVALSD? Error on RVALSDkm/sstat.errorfloatnullableJ/MNRAS/498/2456/rv2Radial velocities for those targets with two stellar components that were identified in the LSD profilesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC identifiermeta.id;meta.mainintHJDHeliocentric Julian Date (HJD-2458000)dtime.epochfloatRVARadial velocity of the primary component derived from the spectral fitskm/sphys.veloc;pos.heliocentricinte_RVAError on RVAkm/sstat.errorintRVALSD? Radial velocity of the primary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloatnullablee_RVALSD? Error on RVALSDkm/sstat.errorfloatnullableRVBLSDRadial velocity of the secondary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloate_RVBLSDError on RVBLSDkm/sstat.errorfloatJ/MNRAS/498/2456/rv3Radial velocities for those targets with three stellar components that were identified in the LSD profilesrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC identifiermeta.id;meta.mainintHJDHeliocentric Julian Date (HJD-2458000)dtime.epochfloatRVARadial velocity of the primary component derived from the spectral fitskm/sphys.veloc;pos.heliocentricfloate_RVAError on RVAkm/sstat.errorfloatRVALSD? Radial velocity of the primary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloatnullablee_RVALSD? Error on RVALSDkm/sstat.errorfloatnullableRVBLSD? Radial velocity of the secondary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloatnullablee_RVBLSD? Error on RVBLSDkm/sstat.errorfloatnullableRVCLSD? Radial velocity of the tertiary component derived from the LSD profileskm/sphys.veloc;pos.heliocentricfloatnullablee_RVCLSD? Error on RVCLSDkm/sstat.errorfloatnullable