J/ApJ/912/72ivo://CDS.VizieR/J/ApJ/912/72doi:10.26093/cds/vizier.19120072CDSMatsuno T.Aoki W.Casagrande L.Ishigaki M.N.Shi J.Takata M.,Xiang M.Yong D.Li H.Suda T.Xing Q.Zhao J.2022-12-09T13:22:09Z2022-11-23T13:39:19ZCDS support team

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

cds-question@unistra.frhalo-starschemical-abundancesradial-velocityline-intensitiesvisible-astronomyspectroscopygiant-starsWe combine asteroseismology, optical high-resolution spectroscopy, and kinematic analysis for 26 halo red giant branch stars in the Kepler field in the range of -2.5<[Fe/H]{<}-0.6. After applying theoretically motivated corrections to the seismic scaling relations, we obtain an average mass of 0.97+/-0.03M_{sun}_ for our sample of halo stars. Although this maps into an age of ~7Gyr, significantly younger than independent age estimates of the Milky Way stellar halo, we considered this apparently young age to be due to the overestimation of stellar mass in the scaling relations. There is no significant mass dispersion among lower red giant branch stars (logg>2), which constrains the relative age dispersion to <18%, corresponding to <2Gyr. The precise chemical abundances allow us to separate the stars with [Fe/H]{>}-1.7 into two [Mg/Fe] groups. While the [{alpha}/Fe] and [Eu/Mg] ratios are different between the two subsamples, [s/Eu], where s stands for Ba, La, Ce, and Nd, does not show a significant difference. These abundance ratios suggest that the chemical evolution of the low-Mg population is contributed by Type Ia supernovae, but not by low- to intermediate-mass asymptotic giant branch stars, providing a constraint on its star formation timescale as 100Myr<{tau}<300Myr. We also do not detect any significant mass difference between the two [Mg/Fe] groups, thus suggesting that their formation epochs are not separated by more than 1.5Gyr.2021ApJ...912...72Mhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/912/72CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toII/246 : 2MASS All-Sky Catalog of Point Sources (Cutri+ 2003)I/345 : Gaia DR2 (Gaia Collaboration, 2018)V/117 : Geneva-Copenhagen Survey of Solar neighbourhood (Holmberg+, 2007)J/AJ/120/1841 : Abundances & Kinematics of Halo & Disk Stars (Fulbright 2000)J/ApJ/530/783 : The r-process enriched giant HD 115444 (Westin+, 2000)J/A+A/416/1117 : Abundances in the early Galaxy (Cayrel+, 2004)J/ApJ/645/613 : Abundances of HD 221170 (Ivans+, 2006)J/A+A/505/117 : Abundances of red giants in 15 GCs (Carretta+, 2009)J/AJ/137/4377 : List of SEGUE plate pairs (Yanny+, 2009)J/A+A/511/L10 : Abundances and space velocities of 94 stars (Nissen+, 2010)J/A+A/512/A54 : Teff and Fbol from Infrared Flux Method (Casagrande+, 2010)J/A+A/523/A17 : Individual stars in Fornax dSph center (Letarte+, 2010)J/A+A/528/A92 : HERES VI. Gal. chemical evolution of Si & C (Zhang+, 2011)J/A+A/530/A15 : Abundances of 94 stars (Nissen+, 2011)J/ApJ/765/L41 : Asteroseismic classification of KIC objects (Stello+, 2013)J/ApJ/771/67 : Abundances for 97 metal-poor stars. II. (Ishigaki+, 2013)J/MNRAS/444/392 : Synthetic Stellar Photometry. I. (Casagrande+, 2014)J/A+A/568/A25 : C and O abundances in stellar populations (Nissen+, 2014)J/AJ/147/136 : Stars of very low metal abundance. VI. (Roederer+, 2014)J/ApJS/215/19 : APOKASC catalog of Kepler red giants (Pinsonneault+, 2014)J/ApJS/220/19 : LAMOST obs. in the Kepler field. I. (De Cat+, 2015)J/MNRAS/450/397 : Spectroscopic study of RGs in Kepler field (Takeda+, 2015)J/MNRAS/456/3655 : Masses and ages of red giants (Martig+, 2016)J/ApJ/817/40 : High-resolution NIR spectra of local giants (Feuillet+, 2016)J/ApJ/823/114 : The Cannon: a new approach to determine masses (Ness+, 2016)J/ApJ/827/50 : Kepler faint red giants (Mathur+, 2016)J/ApJ/832/121 : 4-yr RV survey of red giant in EBs. (Gaulme+, 2016)J/A+A/585/A102 : Copper abundances in solar neighborhood stars (Yan+, 2016)J/A+A/589/A115 : Na and Al abundances of 1303 stars (Smiljanic+, 2016)J/MNRAS/465/3203 : GALAH observational overview (Martell+, 2017)J/A+A/597/A30 : Seismology and sp. of CoRoGEE red giants (Anders+, 2017)J/A+A/608/A46 : Constraining cosmic scatter (Reggiani+, 2017)J/A+A/618/A133 : Non standard s-process in massive rot. stars (Choplin+, 2018)J/ApJ/865/68 : Abundances for 79 Sun-like stars within 100pc (Bedell+, 2018)J/ApJ/860/49 : Opt. sp. of young {alpha}-rich stars (Matsuno+, 2018)J/ApJ/868/110 : R-Process Alliance: 1st release in Gal. halo (Sakari+, 2018)J/ApJS/236/42 : Asteroseismology of ~16000 Kepler red giants (Yu+, 2018)J/ApJS/239/32 : APOKASC-2 Kepler evolved stars (Pinsonneault+, 2018)J/MNRAS/475/5487 : Stellar properties of KIC stars (Silva Aguirre+, 2018)J/MNRAS/474/2580 : Evolution of neutron-capture elements (Spina+, 2018)J/MNRAS/475/3633 : Mass and age of red giant branch stars (Wu+, 2018)J/A+A/624/A19 : GALAH survey, chemodynamical analyse with TGAS (Buder+, 2019)J/A+A/624/A78 : Masses and ages of 1059 HARPS-GTO stars (Delgado Mena+, 2019)J/A+A/625/A33 : Radial velocity time series of HD 122563 (Creevey+, 2019)J/A+A/626/A15 : Sculptor Red Giant Branch stars abundances (Hill+, 2019)J/A+A/627/A173 : Abundances for 4 metal-poor stars (Valentini+, 2019)J/A+A/631/A171 : Neutron-capture elements in dwarf gal. (Skuladottir+, 2019)J/MNRAS/482/965 : Age of the Galactic stellar halo from Gaia WDs (Kilic+, 2019)J/AJ/157/70 : Sodium-rich stars among metal-poor stars (Pereira+, 2019)J/MNRAS/493/5195 : Milky Way halo stars ages and kinematics (Das+, 2020)J/A+A/644/A83 : Jurassic structure (Fernandez-Trincado+, 2020)J/A+A/645/A85 : Age dissection of the Milky Way discs (Miglio+, 2021)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/912/72https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/912/72http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/912/72https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/912/72https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/912/72http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/912/72GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/912/72/stars (Observation log (Table 1) and adopted stellar parameters (Table 6))https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/912/72/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/912/72/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/912/72/stars?GETtext/xml+votable180.050000true290.909756440.30789140.0055555555555555566/14762 14765 14782 14818 14828 14929-14934 14940 14948 14963-14964 14973 15115-15116 15118 15124 15139-15140 15158 15168 15170-151711.9867573869263685e-19 3.916500758235022e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/912/72?format=asciiOpticaldefaultJ/ApJ/912/72/starsObservation log (Table 1) and adopted stellar parameters (Table 6)HRV-L[-387/-13.5]? LAMOST DR5 radial velocity (4)km/sphys.veloc;pos.heliocentricfloatnullable[Fe/H]-L[-2.5/-0.6]? LAMOST DR5 [Fe/H] abundancephys.abund.FefloatnullableHRV-A[-381/-7]? APOGEE DR16 radial velocitykm/sphys.veloc;pos.heliocentricfloatnullable[Fe/H]-A[-2.15/-0.51]? APOGEE DR16 [Fe/H] abundance (4)phys.abund.FefloatnullableHRV-G[-379.3/-6.6]? Gaia DR2 radial velocitykm/sphys.veloc;pos.heliocentricfloatnullablee_HRV-G[0.37/4.3]? HRV-G uncertaintykm/sstat.errorfloatnullableGmag[10.14/13.21]? Gaia DR2 G-band magnitudemagphot.mag;em.optfloatnullablen_KIC? -17 = 2017 observation for KIC 12017985 (G1)meta.notecharTeff[4644/5154]? Effective temperatureKphys.temperature.effectiveintnullablee_Teff[31/74]? Teff uncertaintyKstat.error;phys.temperature.effectiveintnullablelogg[1.65/3.15]? Log of surface gravitylog(cm.s**-2)phys.gravityfloatnullableEWsDisplay the equivalent widths for this star (link to Table 5)meta.ref.urlcharLAMOSTDisplay data from the LAMOST DR4 catalog (V/153)meta.ref.urlcharAPOGEEDisplay data from the APOGEE DR16 catalog (III/284)meta.ref.urlcharGaiaDisplay data from Gaia DR2 (I/345)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.mainrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintKICKIC number (G1)meta.id;meta.mainintprimaryf_KICe = Flag on KIC 10992126; flag added by CDS (1)meta.codecharDateDate of observation (UT) (2)time.epochnullableDate2[11]? Second date of observation if anydtime.epoch;obsintnullableExp[600/5400] Exposure timestime.duration;obs.exposureintS/N[107/265] Signal-to-noise ratio from the continuum around 5765{AA} per 0.024{AA} pixelstat.snrfloatHRV[-381/-7]? Heliocentric radial velocity from Subaru/HDS (3)km/sphys.veloc;pos.heliocentricfloatnullablee_logg[0.004/0.03]? logg uncertaintylog(cm.s**-2)stat.errorfloatnullableVt[1.2/1.92]? Microturbulent velocitykm/sphys.velocfloatnullablee_Vt[0.03/0.12]? Vt uncertaintykm/sstat.errorfloatnullable[Fe/H][-2.5/-0.62]? Log of Fe/H abundancelog(Sun)phys.abund.Fefloatnullablee_[Fe/H][0.016/0.06]? [Fe/H] uncertaintylog(Sun)stat.error;phys.abund.FefloatnullableNabDisplay the abundance measurements for this star (link to Table 7)meta.numberintnullableJ/ApJ/912/72/table5Line list and measured equivalent widthsKIC9335536[5.4/161]? KIC9335536 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC9339711[2.8/173.6]? KIC9339711 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableIonSpecies identifierphys.atmol.ionStagecharrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintlambda[4053.8/6771.1] Wavelength in Angstroms0.1nmem.wldoubleExPot[0/5.11] Excitation potentialeVphys.atmol.excitationfloatlog(gf)[-9.72/0.6] Log oscillator strengthphys.atmol.oscStrengthfloatSyn"syn"=Lines to which spectral synthesis appliedmeta.codecharKIC5184073[5.5/181.2]? KIC5184073 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC5439372[3.7/145]? KIC5439372 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC5446927[9.8/194.3]? KIC5446927 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC5698156[7/193]? KIC5698156 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC5858947[2.6/238.6]? KIC5858947 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC5953450[4.6/195.6]? KIC5953450 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.VfloatnullableKIC6279038[2.7/144]? KIC6279038 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.RfloatnullableKIC6520576[1.7/149.1]? KIC6520576 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.RfloatnullableKIC6611219[7/201.5]? KIC6611219 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.RfloatnullableKIC7191496[4/139.1]? KIC7191496 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.RfloatnullableKIC7693833[1.7/116]? KIC7693833 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC7948268[4/163]? KIC7948268 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC10460723[3.7/163.7]? KIC10460723 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.50-100nmfloatnullableKIC10737052[3.8/187.6]? KIC10737052 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.50-100nmfloatnullableKIC11563791[4.8/189]? KIC11563791 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.100-200nmfloatnullableKIC8350894[7.4/187.4]? KIC8350894 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC9583607[8.6/189]? KIC9583607 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC9696716[2.6/146.3]? KIC9696716 equivalent width (1)1e-13mspect.line.eqWidth;em.opt.IfloatnullableKIC10083815[9.4/191]? KIC10083815 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.50-100nmfloatnullableKIC10096113[8/241.5]? KIC10096113 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.50-100nmfloatnullableKIC10328894[3/140]? KIC10328894 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.50-100nmfloatnullableKIC11566038[3/167]? KIC11566038 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.100-200nmfloatnullableKIC12017985[2.7/192.3]? KIC12017985 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.100-200nmfloatnullableKIC12017985-17[3.8/144.2]? KIC12017985 equivalent width from the 2017 observation (1)1e-13mspect.line.eqWidth;em.UV.100-200nmfloatnullableKIC12253381[2/152.7]? KIC12253381 equivalent width (1)1e-13mspect.line.eqWidth;em.UV.100-200nmfloatnullableHD122563[0.7/164.2]? HD122563 equivalent width (1)1e-13mspect.line.eqWidthfloatnullableJ/ApJ/912/72/table7AbundancesKICKIC numbermeta.id;meta.mainintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintn_KIC? -17 = 2017 observation for KIC 12017985 (G1)meta.notecharIonSpecies identifierphys.atmol.ionStagechar[X/H][-3.52/-0.09]? log number abundance relative to hydrogenmeta.idfloatnullablee_[X/H][0/0.17]? Uncertainty in [X/H]stat.error;phys.abundfloatnullable[X/Fe][-1.1/0.99]? log number abundance relative to ironphys.abundfloatnullablee_[X/Fe][0/0.16]? Uncertainty in [X/Fe]stat.error;phys.abundfloatnullable