J/A+A/652/A60ivo://CDS.VizieR/J/A+A/652/A60doi:10.26093/cds/vizier.36520060CDSFritzewski D.J.Barnes S.A.James D.J.Strassmeier K.G.2023-01-11T14:19:49Z2021-08-11T09:20:13ZCDS support team

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

cds-question@unistra.frlate-type-starsvariable-starsphotometryopen-star-clustersA very rich cluster intermediate in age between the Pleiades (150Myr) and the Hyades (600Myr) is needed to probe the rotational evolution, especially the transition between fast and slow rotation that occurs between the two ages. We study the rich 300Myr-old open cluster NGC 3532 to probe this important transition and to provide constraints on angular momentum loss. Measuring the rotation periods builds on our prior work of providing spectroscopic membership information for the cluster, and it supports the chromospheric activity measurements of cluster stars that we provide in a companion paper. Using 42d-long photometric time series observations obtained with the Yale 1m telescope at CTIO, we measured rotation periods for members of NGC 3532 and compared them with the predictions of angular momentum evolution models. We directly measured 176 photometric rotation periods for the cluster members. An additional 113 photometric rotation periods were identified using activity information, described fully in the companion paper, resulting in a total sample containing 279 rotation periods for FGKM stars in NGC 3532. The colour-period diagram constructed from this rich data set shows a well-populated and structured slow rotator sequence, and a fast rotator sequence evolved beyond zero-age main sequence age whose stars are in transition from fast to slow rotation. The slow rotator sequence itself is split into slightly slower and faster rotators, a feature we trace to photometric binary status. We also identify an extended slow rotator sequence extending to P~32d, apparently the analogue of the one we previously identified in NGC 2516. We compare our period distribution to rotational isochrones in colour-period space and find that all considered models have certain shortcomings. Using more detailed spin-down models, we evolve the rotation periods of the younger NGC 2516 forward in time and find that the spindown of the models is too aggressive with respect to the slow rotators. In contrast, stars on the evolved fast rotator sequence are not spun down strongly enough by these models. Our observations suggest a shorter crossing time for the rotational gap, one we estimate to be ~80Myr for early-K dwarfs.2021A&A...652A..60Fhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/652/A60CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/345 : Gaia DR2 (Gaia Collaboration, 2018)J/AJ/141/115 : BV(RI)c photometry on NGC 3532 (Clem+ 2011)J/A+A/622/A110 : Spectroscopic membership for NGC 3532 (Fritzewski+ 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/652/A60https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/652/A60http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/652/A60https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/652/A60https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/652/A60http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/652/A60GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/652/A60/table2 (Rotation periods and photometric colours for 279 solar-like members of the open cluster NGC 3532)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/652/A60/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/652/A60/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/652/A60/table2?GETtext/xml+votable180.050000true167.35092-58.727610.0055555555555555566/37933 37938 379443.322582951404819e-19 3.852589004194616e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/652/A60?format=asciidefaultJ/A+A/652/A60/table2Rotation periods and photometric colours for 279 solar-like members of the open cluster NGC 3532P90Variability amplitudemagsrc.var.amplitudefloatClass[0/3] Classification of period (2)meta.codeintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDID(s) from Fritzewski et al. (2019A&A...622A.110F, Cat. J/A+A/622/A110)meta.idcharGaiaDR2Gaia DR2 designationmeta.id;meta.mainCLHWID from Clem et al. (2011AJ....141..115C, Cat. J/AJ/141/115)meta.idintRA_ICRSRight ascension from Gaia DR2 (ICRS) at Ep=2015.5 (Cat. I/345)degpos.eq.ra;meta.mainSimbadSimbad column added by the CDSmeta.ref.urlchar_RA.icrsRight ascension (ICRS) at Epoch=J2015.5 (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.ranullableindexed_DE.icrsDeclination (ICRS) at Epoch=J2015.5 (computed by VizieR, not part of the original data. The format may include more digits than the original data because of internal accuracy requirements in VizieR and across other CDS services)degpos.eq.decnullableindexedProtRotation perioddtime.periodfloatDE_ICRSDeclination from Gaia DR2 (ICRS) at Ep=2015.5degpos.eq.dec;meta.main(B-V)0(B-V)_0 colour from Clem et al. (2011AJ....141..115C, Cat. J/AJ/141/115) (1)magphot.color;em.opt.B;em.opt.VfloatVmagV magnitude from Clem+ (2011AJ....141..115C, Cat. J/AJ/141/115)magphot.mag;em.opt.Vfloat(V-Ks)0? (V-Ks)_0 colour based on Vmag and 2MASS Ks (1)magphot.color;em.IR.H;em.IR.Kfloatnullablee_Protuncertainty in rotation perioddstat.errorfloatBinary[0/1] Binary status (1 for true)meta.codeint