J/MNRAS/523/802ivo://CDS.VizieR/J/MNRAS/523/802CDSJeffries R.D.Jackson R.J.Wright N.J.Weaver G.Gilmore G.,Randich S.Bragaglia A.Korn A.J.Smiljanic R.Biazzo K.Casey A.R.,Frasca A.Gonneau A.Guiglion G.Morbidelli L.Prisinzano L.,Sacco G.G.Tautvaisiene G.Worley C.C.Zaggia S.2026-09-04T12:52:31Z2026-09-04T12:13:42ZCDS support team

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

cds-question@unistra.fropen-star-clustersg-starsmetallicitystellar-agesastrometryline-intensitiesspectroscopyvisible-astronomyeffective-temperaturephotometryWe present an empirical model of age-dependent photospheric lithium depletion, calibrated using a large homogeneously analysed sample of 6200 stars in 52 open clusters, with ages from 2 to 6000 Myr and -0.3 < [Fe/H] < 0.2, observed in the Gaia-ESO spectroscopic survey. The model is used to obtain age estimates and posterior age probability distributions from measurements of the Li I 6708 {AA} equivalent width for individual (pre) main-sequence stars with 3000 < Teff/K < 6500, a domain where age determination from the HR diagram is either insensitive or highly model-dependent. In the best cases, precisions of 0.1 dex in log age are achievable; even higher precision can be obtained for coeval groups and associations where the individual age probabilities of their members can be combined. The method is validated on a sample of exoplanet-hosting young stars, finding agreement with claimed young ages for some, but not others. We obtain better than 10 per cent precision in age, and excellent agreement with published ages, for seven well-studied young moving groups. The derived ages for young clusters (<1 Gyr) in our sample are also in good agreement with their training ages, and consistent with several published model-insensitive lithium depletion boundary ages. For older clusters, there remain systematic age errors that could be as large as a factor of 2. There is no evidence to link these errors to any strong systematic metallicity dependence of (pre) main-sequence lithium depletion, at least in the range -0.29 < [Fe/H] < 0.18. Our methods and model are provided as software - 'Empirical AGes from Lithium Equivalent widthS' (EAGLES).2023MNRAS.523..802Jhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/523/802CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/MNRAS/513/5727 : Lithium study with GESiDR6's PMS stars cluster (Binks+,2022)J/MNRAS/509/1664 : Membership study of 70 stars clusters (Jackson+, 2022)J/MNRAS/504/356 : Updated parameters of 1743 open clusters (Dias+, 2021)J/MNRAS/500/1158 : Rotation and lithium depletion of M35 dwarfsJ/MNRAS/328/45 : Late-type stars members of young groups (Montes+, 2001)J/A+A/676/A129 : Gaia-ESO catalogue version 5.1 (Hourihane+, 2023)J/A+A/668/A49 : Lithium curves of growth (Franciosini+, 2022)J/A+A/666/A121 : Cluster target Giraffe HR15N RV precision (Randich+, 2022)J/A+A/664/A70 : Lithium depletion boundary in stellar assoc.J/A+A/659/A85 : Membership and lithium of young clusters (Franciosini+,2022)J/A+A/653/A72 : Stellar parameters and Li abundances from GES iDR6J/A+A/643/A71 : Members for 20 open clusters (Gutierrez Albarran+, 2020)J/A+A/613/A63 : Lithium content for 148 Pleiades stars (Bouvier+, 2018)J/A+A/566/A50 : Classification of stellar spectra 644-681nm (Damiani+, 2014)J/A+A/564/A90 : M subdwarfs VLT/UVES high resolution spectraJ/A+A/541/A150 : Lithium in M67 and Hyades (Pace+, 2012)J/A+A/479/141 : Iz photometry, RV and EW(Li) in IC 4665 (Manzi+, 2008)J/A+A/442/961 : Lithium content of the Galactic Halo starsJ/A+A/372/862 : Lithium abundances in IC 2602 and IC 2391 (Randich+, 2001)J/ApJ/762/88 : Young stellar kinematic group candidate members (Malo+,2013)J/AJ/153/128 : WOCS. LXXV. Hyades&Praesepe stellar lithium datahttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/523/802https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/523/802http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/523/802https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/523/802https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/523/802http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/523/802GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/523/802/table1 (Training data drawn from 52 cluster ages and metallicities of literature references)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/523/802/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/523/802/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/523/802/table1?GETtext/xml+votable180.050000true271.1291667-24.35833330.005555555555555556Cone search capability for table J/MNRAS/523/802/table2 (*Training data used to calibrate the empirical relations of EWLi as a function of Teff and age for 6200 cluster members observed as part of the Gaia-ESO survey)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/523/802/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/523/802/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/523/802/table2?GETtext/xml+votable180.050000true80.701751.678860.005555555555555556Cone search capability for table J/MNRAS/523/802/table4 (Training and most probable estimated ages of GES clusters from model and fit work described in section 2 and 3)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/523/802/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/523/802/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/523/802/table4?GETtext/xml+votable180.050000true271.1291667-24.35833330.0055555555555555565/4122 5429 5514 5909 5934 9239 9282 9398 9838 6/1576 4298 4783 6148-6149 14336 16447 16576-16577 21372 21518-21519 21529 21550 22224-22225 22239 22249 22433 22499 22892 22894-22895 22980-22981 23612 23695 23704-23706 23717 23719 23728 23730 23745 24322 24330 24344-24345 28806-28807 28812 28822-28823 28890-28891 29523 30215 30635 31785 31787-31788 31790 31809 31812 36953 36955 37122-37123 37227 37229-37231 37240 37242 37279 37294 37313 37316-37318 37586-37587 37787-37788 37790 37809 37933 37944 38016 38018 38441 39181 39183 39192 39194 39205 39216-39218 39252 39254 39257 39259-39260 39358 39685 39696-39698 41466 41649 41678 42153 42156 42177 42374 42380 42464 42496 42959 42980-42981 42983 42992 42994 43034https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/523/802?format=asciiOpticaldefaultJ/MNRAS/523/802/table1Training data drawn from 52 cluster ages and metallicities of literature referencesSimbadNameSimbad column added by the CDSmeta.idcharnullablerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster name from Randich et al. (2022A&A...666A.121R, Cat. J/A+A/666/A121)meta.id.parentchar[Fe/H]Average metallicity of the cluster from Randich et al. (2022A&A...666A.121R, Cat. J/A+A/666/A121)log(Sun)phys.abund.Z;stat.meanfloatNstarThe number of members in each cluster used in our analysis (No.Stars)meta.numberintAgeJ22Cluster ages from three different sources from (2022MNRAS.509.1664J, Cat. J/MNRAS/509/1664) and Franciosini et al. (2022A&A...659A..85F, Cat. J/A+A/659/A85) (Lit_ages)Myrtime.agefloatAgeGESAge from table 3 in Randich et al. (2022A&A...666A.121R, Cat. J/A+A/666/A121) (GES_ages)Myrtime.agefloatAgeDias? Age from Dias et al. (2021MNRAS.504..356D, Cat. J/MNRAS/504/356) (Dias_ages)Myrtime.agefloatnullableAgeMeanThe geometric mean age for each cluster as seen in section 2.1 (Mean_ages)Myrtime.age;stat.meanfloatAssosDisplay the cluster catalogs of Randich et al. 2022A&A...666A.121R, Cat. J/A+A/666/A121, Jackson et al. 2022MNRAS.509.1664J, Cat. J/MNRAS/509/1664 and Dias et al. J/MNRAS/504/356meta.ref.urlchar_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/523/802/table2*Training data used to calibrate the empirical relations of EWLi as a function of Teff and age for 6200 cluster members observed as part of the Gaia-ESO surveyRAJ2000Right ascension (J2000) (RA)degpos.eq.ra;meta.mainSimbadSimbad column added by the CDSmeta.ref.urlcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintWaveWavelength filter value GIRAFFE (Filter = 665.0 nm) and UVES (Filter = 580.0 nm) measurements (FILTER)nmem.wl;instr.filterfloatDEJ2000Declination (J2000) (DEC)degpos.eq.dec;meta.mainAgeEstimated stellar age (AGE)Myrtime.agefloatMemProbability of cluster membership (MEM)stat.fit.goodnessfloat(BP-RP)0? The gaia (G_BP_-G_RP_)_0_ colour magnitude (BP_RPo)magphot.color;em.opt.B;em.opt.RdoublenullableTeffEffective temperature as described in section 2.1 (TEFF)Kphys.temperature.effectiveintEW(Li)Measured equivalent width as described in section 2.1 used to build empirical relations as a function of Teff and age (LiEW)0.0001nmspect.line.eqWidthfloate_EW(Li)Measurement uncertainty of EW(Li) (e_LiEW)0.0001nmstat.errorfloatAssosDisplay the cluster catalogs of Randich et al. 2022A&A...666A.121R, Cat. J/A+A/666/A121, Jackson et al. 2022MNRAS.509.1664J, Cat. J/MNRAS/509/1664 and Dias et al. J/MNRAS/504/356meta.ref.urlcharClusterCluster name (CLUSTER)meta.id.parentcharTargetTarget star name (TARGET)meta.id;meta.maincharRandich22Display the star target of cluster catalog from Randich et al. 2022A&A...666A.121Rmeta.ref.urlcharHourihane23Display the Gaia-ESO catalogue version 5.1 of Hourihane et al. 2023A&A...676A.129H, Cat. J/A+A/676/A129meta.ref.urlcharJ/MNRAS/523/802/table4Training and most probable estimated ages of GES clusters from model and fit work described in section 2 and 3SimbadNameSimbad column added by the CDSmeta.idcharnullableClusterCluster name (Cluster)meta.id.parentcharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlogAgeThe mean logage of the training data taken from the table1.dat (Logage)log(yr)time.age;stat.meanfloate_logAgeUncertainty of logAgelog(yr)stat.error;time.agefloatlogAgefitBest-fitting age or limiting value from model described in sections 2 and 3log(yr)time.agefloatE_logAgefit? Upper uncertainty of logAgefitlog(yr)stat.error;stat.maxfloatnullablee_logAgefit? Lower uncertainty of logAgefitlog(yr)stat.errorfloatnullableChi2? Reduced {chi}2 of best-fitting isochrone of EW_m_ relative to the the measured EW(Li) using model values of dispersion in EW and {rho}m_ (Reduced_{Chi}^2^)stat.fit.chi2floatnullableAssosDisplay the cluster catalogs of Randich et al. 2022A&A...666A.121R, Cat. J/A+A/666/A121, Jackson et al. 2022MNRAS.509.1664J, Cat. J/MNRAS/509/1664 and Dias et al. J/MNRAS/504/356meta.ref.urlchar_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.mainl_logAgefitUpper limit flag of logAgefitmeta.code.errorchar