J/ApJ/879/49ivo://CDS.VizieR/J/ApJ/879/49doi:10.26093/cds/vizier.18790049CDSCurtis J.L.Agueros M.A.Douglas S.T.Meibom S.2021-09-10T07:32:41Z2021-01-12T15:42:43ZCDS support team

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

cds-question@unistra.fropen-star-clustersstellar-massesstellar-spectral-typesphotometryvisible-astronomyStellar rotation was proposed as a potential age diagnostic that is precise, simple, and applicable to a broad range of low-mass stars (<=1M_{sun}_). Unfortunately, rotation period (P_rot_) measurements of low-mass members of open clusters have undermined the idea that stars spin down with a common age dependence (i.e., P_rot{propto}age^0.5^): K dwarfs appear to spin down more slowly than F and G dwarfs. Agueros+ (2018, J/ApJ/862/33) interpreted data for the ~1.4Gyr-old cluster NGC 752 differently, proposing that after having converged onto a slow-rotating sequence in their first 600-700Myr (by the age of Praesepe), K dwarf P_rot_ stall on that sequence for an extended period of time. We use data from Gaia DR2 to identify likely single-star members of the ~1Gyr-old cluster NGC 6811 with Kepler light curves. We measure P_rot_ for 171 members, more than doubling the sample relative to the existing catalog and extending the mass limit from ~0.8 to ~0.6M_{sun}_. We then apply a gyrochronology formula calibrated with Praesepe and the Sun to 27 single G dwarfs in NGC 6811 to derive a precise gyrochronological age for the cluster of 1.04+/-0.07Gyr. However, when our new low-mass rotators are included, NGC 6811's color-P_rot_ sequence deviates away from the naive 1Gyr projection down to T_eff_~4295K (K5V, 0.7M_{sun}), where it clearly overlaps with Praesepe's. Combining these data with P_rot_ for other clusters, we conclude that the assumption that mass and age are separable dependencies is invalid. Furthermore, the cluster data show definitively that stars experience a temporary epoch of reduced braking efficiency where P_rot_ stall, and that the duration of this epoch lasts longer for lower-mass stars.2019ApJ...879...49Chttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/879/49CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/PAZh/25/115 : A study of the open cluster NGC 6811 (Glushkova+, 1999)J/AJ/134/2340 : Praesepe & Coma Berenices cluster membership (Kraus+, 2007)J/ApJ/695/679 : Stellar rotation in M35 (Meibom+, 2009)J/MNRAS/408/475 : HATNet Pleiades Rotation Period Catalogue (Hartman+, 2010)J/ApJ/733/L9 : Stellar rotation for 71 NGC 6811 members (Meibom+, 2011)J/ApJ/733/115 : Rotation periods and membership in M34 (Meibom+, 2011)J/other/RMxAA/47.309 : NGC 6811 & NGC 6830 uvby-{beta} photometry (Pena+, 2011)J/ApJ/757/112 : Stellar diameters. II. K and M-stars (Boyajian+, 2012)J/AJ/145/134 : RVs of 108 stars in Ruprecht 147 (Curtis+, 2013)J/AJ/145/7 : UBVRI CCD photom. of the open cluster NGC 6811 (Janes+, 2013)J/ApJ/776/67 : Rotational tracks (van Saders+, 2013)J/AJ/148/51 : WIYN Open Cluster. LXI. NGC6819 phot. (Anthony-Twarog+, 2014)J/ApJS/211/24 : Rotation periods of Kepler MS stars (McQuillan+, 2014)J/ApJ/804/64 : Empirical and model parameters of 183 M dwarfs (Mann+, 2015)J/other/ApSS/355.267 : NGC 6811 CCD UBVRI photometry (Yontan+, 2015)J/ApJS/225/32 : Extended abundance analysis of cool stars (Brewer+, 2016)J/ApJ/822/47 : K2 rotation periods for 65 Hyades members (Douglas+, 2016)J/AJ/152/113 : Pleiades members with K2 LCs. I. Periods (Rebull+, 2016)J/ApJ/831/11 : KIC 9777062 RVs & NGC6811 asteroseismology (Sandquist+, 2016)J/ApJ/838/115 : Asteroseismic data of 8 Kepler red giants (Arentoft+, 2017)J/ApJ/842/83 : Praesepe members rot. periods from K2 LCs (Douglas+, 2017)J/ApJ/862/33 : Expanded membership cat. for NGC752 (Agueros+, 2018)J/A+A/616/A10 : 46 open clusters GaiaDR2 HR diag. (Gaia Collaboration, 2018)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/879/49https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/879/49http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/879/49https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/879/49https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/879/49http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/879/49GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/879/49/table1 (Data for the NGC 6811 benchmark sample)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/879/49/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/879/49/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/879/49/table1?GETtext/xml+votable180.050000true294.410721146.48685640.0055555555555555566/14778 14779 14782 15120 15121 151241.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/879/49?format=asciiOpticaldefaultJ/ApJ/879/49/table1Data for the NGC 6811 benchmark samplePer[0.6/19] Rotational period (2)dtime.periodfloatrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeq[1/171] Sequential running numbermeta.idintKIC[9095289/10018969] Kepler Input Catalog IDmeta.id;meta.mainintGaiaGaia DR2 Source IDmeta.id.crossGmag[13.3/19] Gaia DR2 G magnitudemagphot.mag;em.optfloatBP-RP[0.5/2.1] Gaia BP-RP color indexmagphot.color;em.opt.B;em.opt.RfloatTeff[3740/6507] Effective temperature (1)Kphys.temperature.effectiveintMass[0.5/1.3] MasssolMassphys.massfloatSpTSpectral Typesrc.spTypechare_Per[0.0006/1]? 1{sigma} Uncertainty in Per (3)dstat.errorfloatnullableNQ[1/15] Number of Quartersmeta.numberintf_SeqStar code (4)meta.codecharSimbadSimbad column added by the CDSmeta.ref.urlchar_RABarycentric positions (ICRS) at Ep=2000.0 from Gaia DR2 (I/345) (right ascension part)degpos.eq.ra;meta.main_DEBarycentric positions (ICRS) at Ep=2000.0 from Gaia DR2 (I/345) (declination part)degpos.eq.dec;meta.main