J/A+A/628/A41ivo://CDS.VizieR/J/A+A/628/A41doi:10.26093/cds/vizier.36280041CDSPizzocaro D.Stelzer B.Poretti E.Raetz S.Micela G.Belfiore A.,Marelli M.Salvetti D.De Luca A.2020-11-24T08:07:24Z2019-11-12T15:01:41ZCDS support team

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

cds-question@unistra.frx-ray-sourcesphotometryThe relation between magnetic activity and rotation in late-type stars provides fundamental information on stellar dynamos and angular momentum evolution. Rotation-activity studies found in the literature suffer from inhomogeneity in the measurement of activity indexes and rotation periods. We overcome this limitation with a study of the X-ray emitting, late-type main-sequence stars observed by XMM-Newton and Kepler. We measured rotation periods from photometric variability in Kepler light curves. As activity indicators, we adopted the X-ray luminosity, the number frequency of white-light flares, the amplitude of the rotational photometric modulation, and the standard deviation in the Kepler light curves. The search for X-ray flares in the light curves provided by the EXTraS (Exploring the X-ray Transient and variable Sky) FP-7 project allows us to identify simultaneous X-ray and white-light flares. A careful selection of the X-ray sources in the Kepler field yields 102 main-sequence stars with spectral types from A to M. We find rotation periods for 74 X-ray emitting main-sequence stars, 20 of which do not have period reported in the previous literature. In the X-ray activity-rotation relation, we see evidence for the traditional distinction of a saturated and a correlated part, the latter presenting a continuous decrease in activity towards slower rotators. For the optical activity indicators the transition is abrupt and located at a period of ~10d but it can be probed only marginally with this sample, which is biased towards fast rotators due to the X-ray selection. We observe seven bona-fide X-ray flares with evidence for a white-light counterpart in simultaneous Kepler data. We derive an X-ray flare frequency of ~0.15d^-1^, consistent with the optical flare frequency obtained from the much longer Kepler time-series.2019A&A...628A..41Phttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/628/A41CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toI/322 : UCAC4 Catalogue (Zacharias+, 2012)V/133 : Kepler Input Catalog (Kepler Mission Team, 2009)IX/46 : XMM-Newton Serendipitous Source Catalogue 3XMM-DR5J/ApJS/199/30 : Effective temperature scale for KIC stars (Pinsonneault+, 2012)J/ApJ/775/L11 : Stellar rotation periods for KOIs (McQuillan+, 2013)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/628/A41https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/628/A41http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/628/A41https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/628/A41https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/628/A41http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/628/A41GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/628/A41/tablea1 (*KIC (Brown et al. 2011, J/AJ/142/112) photometry all the 125 stars in the Kepler/XMM-Newton sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/628/A41/tablea1?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/628/A41/tablea1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/628/A41/tablea1?GETtext/xml+votable180.050000true295.061140.083270.0055555555555555565/3688 6/14738 14744 14751 14772-14773 14777 14816 14949 14960 15106 15112 15120-15121 15169 15171-151728.650015785639275e-20 1.4134638842407062e-18https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/628/A41?format=asciiX-raydefaultJ/A+A/628/A41/tablea2Fundamental stellar parameters for all 125 stars in the Kepler/XMM-Newton sampleKICKIC IDmeta.id;meta.mainintdDistancepcpos.distancefloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintAVAbsorption in V bandmagphot.magfloatn_AV[=] = for adopted valuemeta.notecharloggSurface gravity in solar unitlog(cm.s**-2)phys.gravityfloatn_logg[=] = for adopted valuemeta.notechar[Fe/H]Metallicity in solar unitlog(Sun)phys.abund.Zfloatn_[Fe/H][=] = for adopted valuemeta.notecharTeffEffective temperatureKphys.temperature.effectiveinte_Teffrms uncertainty on effective temperatureKstat.error;phys.temperature.effectiveinte_drms uncertainty on Distancepcstat.errorfloatr_dReference for Distancemeta.ref;pos.framecharM*Stellar masssolMassphys.massfloate_M*rms uncertainty on Stellar masssolMassstat.errorfloatlogLbolBolometric luminositylog(solLum)phys.luminosityfloate_logLbolrms uncertainty on Bolometric luminositylog(solLum)stat.errorfloatSpTypeMK spectral typesrc.spTypecharVarVariability classification code (1)meta.code.classcharFlagFlag (2)meta.code.errorcharJ/A+A/628/A41/tablea3Rotation and flaring parameters derived from the Kepler light curves for all 74 rotationally-variable main-sequence stars in the Kepler/XMM-Newton samplerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC IDmeta.id;meta.mainintProtRotation period from ACFdtime.periodfloatR0? Rossby number from Eq. (36) in Cranmer & Saar (2011ApJ...741...54C)stat.paramfloatnullablelogRperPercentile amplitude of the rotation cycle after McQuillan et al. (2013, J/ApJ/775/L11)%src.var.amplitudefloatSphStandard deviation of the whole lightcurve(10-6)stat.stdevintSph5Average of the standard deviation for 5 rotation cycles after Mathur et al. (2014, Space Weather Space Climate, 4, A15)(10-6)stat.stdevintSflatMinimum of the standard deviations from all quarters for the "flattened" lightcurves(10-6)stat.stdevfloatlogApeak? Median of relative flare peak amplitudeslog(mag)src.var.amplitudefloatnullableb_logApeak? Minimum relative flare peak amplitudelog(mag)src.var.amplitude;stat.min;stat.maxfloatnullableB_logApeak? Maximum relative flare peak amplitudelog(mag)src.var.amplitude;stat.maxfloatnullableFlarerate? Flare rated**-1meta.numberfloatnullableJ/A+A/628/A41/tablea4X-ray luminosity (in the 0.2-2keV energy band), observed NUV and FUV luminosity, and NUV and FUV chromospheric excess luminosityrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC IDmeta.id;meta.mainintLXX-ray luminosity (in the 0.2-2keV energy band) (in 10+29^erg/s)1e+12Wphys.luminosity;em.X-rayfloate_LXrms uncertainty on LX (in 10+29^erg/s)1e+12Wstat.errorfloatLNUV? Observed NUV luminosity (in 10+29^erg/s)1e+12Wphys.luminosity;em.UV.200-300nmfloatnullablee_LNUV? rms uncertainty on LNUV (in 10+29^erg/s)1e+12Wstat.errorfloatnullableLFUV? Observed FUV luminosity (in 10+29^erg/s)1e+12Wphys.luminosity;em.UV.100-200nmfloatnullablee_LFUV? rms uncertainty on LFUX (in 10+29^erg/s)1e+12Wstat.errorfloatnullableLNUVexc? NUV chromospheric excess luminosity (in 10+29^erg/s)1e+12Wphys.luminosity;em.UV.200-300nmfloatnullableLFUVexc? FUV chromospheric excess luminosity (in 10+29^erg/s)1e+12Wphys.luminosity;em.UV.100-200nmfloatnullableJ/A+A/628/A41/tablea1*KIC (Brown et al. 2011, J/AJ/142/112) photometry all the 125 stars in the Kepler/XMM-Newton sampleSimbadNameSimbad column added by the CDSmeta.idcharKICKIC IDmeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintJmag2MASS J magnitudemagphot.mag;em.IR.JfloatHmag2MASS H magnitudemagphot.mag;em.IR.HfloatKsmag2MASS Ks magnitudemagphot.mag;em.IR.KfloatUmag? U magnitudemagphot.mag;em.opt.UfloatnullableBmag? B magnitudemagphot.mag;em.opt.BfloatnullableVmag? V magnitudemagphot.mag;em.opt.VfloatnullableKpmagKepler magnitudemagphot.mag;em.optfloatgmag? SDSS g magnitudemagphot.mag;em.opt.Bfloatnullablermag? SDSS r magnitudemagphot.mag;em.opt.Rfloatnullableimag? SDSS i magnitudemagphot.mag;em.opt.Ifloatnullablezmag? SDSS z magnitudemagphot.mag;em.opt.IfloatnullableFUVmag? GALEX FUV magnitudemagphot.mag;em.UV.100-200nmfloatnullableNUVmag? GALEX NU magnitudemagphot.mag;em.UV.200-300nmfloatnullablekicDisplay the KIC (Cat. V/133) datameta.ref.urlchar_RAPositions form KIC (Cat. V/133) (right ascension part)degpos.eq.ra;meta.main_DEPositions form KIC (Cat. V/133) (declination part)degpos.eq.dec;meta.main