J/A+A/586/A51ivo://CDS.VizieR/J/A+A/586/A51doi:10.26093/cds/vizier.35860051CDSMassari D.Fiorentino G.McConnachie A.Bono G.Dall'Ora M.,Ferraro I.Iannicola G.Stetson P.B.Turri P.Tolstoy E.2016-01-26T06:19:48Z2016-01-26T07:19:24ZCDS support team

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

cds-question@unistra.frglobular-star-clustersinfrared-photometryGlobular clusters are the oldest stellar systems in the Milky Way, and they probe the early epoch of the Galaxy formation. However, the uncertainties on their absolute age are still too large to soundly constrain how the Galactic structures have assembled. The aim of this work is to obtain an accurate estimate of the absolute age of the globular cluster NGC 2808 using deep IR data obtained with the multi-conjugate adaptive optics system operating at the Gemini South telescope (GeMS). This exquisite photometry, combined with that obtained in V and I-bands with HST, allowed us to detect the faint Main Sequence Knee feature in NGC 2808 colour magnitude diagram. The difference between this point and the main sequence turn-off is a good age estimator that provides ages with unprecedented accuracy.2016A&A...586A..51Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/586/A51CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/586/A51https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/586/A51http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/586/A51https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/586/A51https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/586/A51http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/586/A51GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/586/A51/photom (Photometric data)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/586/A51/photom?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/586/A51/photom?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/586/A51/photom?GETtext/xml+votable180.050000true137.9824006-64.86961250.0055555555555555566/372947.952274030004205e-20 1.7798557115773645e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/586/A51?format=asciiInfrareddefaultJ/A+A/586/A51/table1Observing conditionsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintNightNight of observation (Month Day)obs.param;obscharFilter[KJ] Filter usedinstr.setup;instr.filtercharTexpExposure timetime.duration;obs.exposurecharSeeingSeeingarcsecinstr.obsty.seeingfloatJ/A+A/586/A51/photomPhotometric dataDEJ2000Declination (J2000) (1)degpos.eq.dec;meta.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIDStar identification numbermeta.id;meta.mainintRAJ2000Right ascension (J2000) (1)degpos.eq.ra;meta.mainJmagJ-band magnitudemagphot.mag;em.IR.JfloatKmagK-band magnitudemagphot.mag;em.IR.Kfloat