J/MNRAS/475/3633ivo://CDS.VizieR/J/MNRAS/475/3633doi:10.26093/cds/vizier.74753633CDSWu Y.Xiang M.Bi S.Liu X.Yu J.Hon M.Sharma S.Li T.Huang Y.,Liu K.Zhang X.Li Y.Ge Z.Tian Z.Zhang J.Zhang J.2024-08-18T20:18:06Z2021-05-05T10:09:53ZCDS support team

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

cds-question@unistra.frgiant-starsstellar-massesstellar-ageschemical-abundancesObtaining accurate and precise masses and ages for large numbers of giant stars is of great importance for unraveling the assemblage history of the Galaxy. In this paper, we estimate masses and ages of 6940 red giant branch (RGB) stars with asteroseismic parameters deduced from Kepler photometry and stellar atmospheric parameters derived from LAMOST spectra. The typical uncertainties of mass is a few per cent, and that of age is ~20 per cent. The sample stars reveal two separate sequences in the age-[{alpha}/Fe] relation - a high-{alpha} sequence with stars older than ~8Gyr and a low-{alpha} sequence composed of stars with ages ranging from younger than 1Gyr to older than 11Gyr. We further investigate the feasibility of deducing ages and masses directly from LAMOST spectra with a machine learning method based on kernel based principal component analysis, taking a sub-sample of these RGB stars as a training data set. We demonstrate that ages thus derived achieve an accuracy of ~24 per cent. We also explored the feasibility of estimating ages and masses based on the spectroscopically measured carbon and nitrogen abundances. The results are quite satisfactory and significantly improved compared to the previous studies.2018MNRAS.475.3633Whttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/MNRAS/475/3633CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toV/133 : Kepler Input Catalog (Kepler Mission Team, 2009)V/164 : LAMOST DR5 catalogs (Luo+, 2019)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/MNRAS/475/3633https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/MNRAS/475/3633http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/MNRAS/475/3633https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/MNRAS/475/3633https://vizier.iucaa.in/viz-bin/votable?-source=J/MNRAS/475/3633http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/MNRAS/475/3633GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/MNRAS/475/3633/table1 (Deduced parameters of the 3726 uniq RGB stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/MNRAS/475/3633/table1?https://vizier.iucaa.in/viz-bin/conesearch/J/MNRAS/475/3633/table1?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/MNRAS/475/3633/table1?GETtext/xml+votable180.050000true286.305772246.98989970.0055555555555555564/922-923 933-935 944-945 5/3645-3647 3683 3704 3706 3730-3731 3760 3784-3786 3788-3789 3792 6/14567 14573 14575 14577-14579 14731 14738 14744 14746-14747 14750-14751 14792 14794-14795 14822 14828 14830-14831 14914-14915 14917-14919 15044-15045 15057 15059-15062 15148-15150 15160-15161 15172 15174 15176 15178 15200 15232-15233https://cdsarc.cds.unistra.fr/viz-bin/moc/J/MNRAS/475/3633?format=asciidefaultJ/MNRAS/475/3633/table1Deduced parameters of the 3726 uniq RGB starsMassMasssolMassphys.massdouble[C/H]Abundance [C/H]phys.abunddoublerecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintspIDLAMOST spectrum identifiermeta.idcharKICKIC numbermeta.id;meta.mainintTeffEffective temperatureKphys.temperature.effectivedoublee_Teffrms uncertainty on TeffKstat.error;phys.temperature.effectivedoubleloggSurface gravitylog(cm.s**-2)phys.gravitydoublee_loggrms uncertainty on logglog(cm.s**-2)stat.errordouble[Fe/H]Metallicityphys.abund.Zdoublee_[Fe/H]rms uncertainty on [Fe/H]stat.error;phys.abund.Fedouble[alpha/Fe]Abundance [alpha/Fe]phys.abunddoublee_[alpha/Fe]rms uncertainty on [alpha/Fe]stat.error;phys.abunddoublee_[C/H]rms uncertainty on [C/H]stat.error;phys.abunddouble[N/H]Abundance [N/H]phys.abunddoublee_[N/H]rms uncertainty on [N/H]stat.error;phys.abunddoublednuFrequency separation of two modes of the same spherical degree and consecutive radial orderuHzem.freq;src.vardoublee_dnurms uncertainty on dnuuHzstat.errordoublenumaxFrequency with the maximal oscillation poweruHzem.freq;src.vardoublee_numaxrms uncertainty on numaxuHzstat.errordoublee_Massrms uncertainty on MasssolMassstat.error;phys.massdoubleAgeAgeGyrtime.agedoublee_Agerms uncertainty on AgeGyrstat.error;time.agedoubleLAMOST-DR4Display the LAMOST DR4 data (Cat. V/153)meta.ref.urlcharSimbadSimbad column added by the CDSmeta.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.main