J/A+A/490/777ivo://CDS.VizieR/J/A+A/490/777doi:10.26093/cds/vizier.34900777CDSLind K.Korn A.J.Barklem P.S.Grundahl F.2018-02-01T11:50:43Z2010-04-22T16:20:30ZCDS support team

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

cds-question@unistra.frglobular-star-clusterspopulation-ii-starschemical-abundancesEvolutionary trends in the surface abundances of heavier elements have recently been identified in the globular cluster NGC 6397 ([Fe/H]=-2), indicating the operation of atomic diffusion in these stars. Such trends constitute important constraints for the extent to which diffusion modifies the internal structure and surface abundances of solar-type, metal-poor stars. We perform an independent check of the reality and size of abundance variations within this metal-poor globular cluster. Observational data covering a large stellar sample, located between the cluster turn-off point and the base of the red giant branch, are homogeneously analysed. The spectroscopic data were obtained with the medium-high resolution spectrograph FLAMES/GIRAFFE on VLT-UT2 (R~27000). We derive independent effective-temperature scales from profile fitting of Balmer lines and by applying colour-Teff calibrations to Stroemgren uvby and broad-band BVI photometry. An automated spectral analysis code is used together with a grid of MARCS model atmospheres to derive stellar surface abundances of Mg, Ca, Ti, and Fe.2008A&A...490..777Lhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/490/777CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicerelated-toJ/A+A/287/769 : UV photometry of NGC 6397 (Burgarella+ 1994)J/ApJS/99/637 : Equivalent widths for 54 red giants (Norris+ 1995)J/PASP/108/682 : Low-Mass Stars in Outer Field in NGC 6397 (Mould+, 1996)J/A+AS/122/1 : BV photometry of variables in NGC 6397 (Kaluzny, 1997)J/A+A/425/509 : VI photometry of NGC 6397 (Andreuzzi+, 2004)J/A+A/503/545 : Equivalent widths of Li, Na, Fe, Ca in NGC 6397 (Lind+, 2009)J/A+A/505/L13 : Lithium in globular NGC 6397 (Gonzalez Hernandez+, 2009)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/490/777https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/490/777http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/490/777https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/490/777https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/490/777http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/490/777GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/490/777/table4 (Stellar abundances derived for the sample stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/490/777/table4?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/490/777/table4?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/490/777/table4?GETtext/xml+votable180.050000true265.044553.62813890.0055555555555555566/100673.352923723967259e-19 3.9105737390043815e-19https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/490/777?format=asciiOpticaldefaultJ/A+A/490/777/table4Stellar abundances derived for the sample starsn_Seq[*] * for the targets of Korn et al. (2007ApJ...671..402K)meta.notecharRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.mainTHaH{alpha} temperatureKphys.temperatureintloggGravity surfacelog(cm.s**-2)phys.gravityfloatxiMicroturbulent velocitykm/sphys.velocfloatlog(Mg)Magnesium abundance (1)phys.abundfloatlog(Ca)Calcium abundance(1)phys.abundfloatlog(Ti)Titanium abundance(1)phys.abundfloatlog(Fe)Iron abundance(1)phys.abundfloatv-yv-y colour index (Stroemgren)magphot.color;em.opt.B;em.opt.VfloatT(v-y,D)Dwarf temperature from v-y colour indexKphys.temperatureintT(v-y,G)Giant temperature from v-y colour indexKphys.temperatureintV-IV-I colour indexmagphot.color;em.opt.V;em.opt.IfloatT(V-I,D)Dwarf temperature from V-I colour indexKphys.temperatureintT(V-I,G)Giant temperature from V-I colour indexKphys.temperatureintrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintSeqSequential number, Cl* NGC 6397 KGR NNNNNN in Simbadmeta.recordintVmagV magnitudemagphot.mag;em.opt.VfloatJ/A+A/490/777/table5List of lines used in the abundance analysis, with references to the oscillator strengths usedrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintIonIonphys.atmol.ionStagecharlambdaWavelength0.1nmem.wldoublechiExcitation potentialeVphys.atmol.excitationfloatloggfOscillator strengthphys.atmol.oscStrengthfloatr_loggfReference for loggf (1)meta.ref;pos.frameintParam? van der Waals damping data (2)phys.dampingfloatnullableWaals? van der Waals logarithm of FWHM per unit perturber number density at 10000Klog(rad.s**-1.cm**-3)phys.dampingfloatnullableStarkStark logarithm of FWHM per unit perturber number density at 10000Klog(rad.s**-1.cm**-3)phys.dampingfloatlog(FWHM)Radiative damping datalog(rad.s**-1)phys.dampingfloatdlblueExtent of the spectral windows used for fitting of each line, blue-wards of the central wavelength (3)0.1pminstr.bandwidthintdlrefExtent of the spectral windows used for fitting of each line, red-wards of the central wavelength (3)0.1pminstr.bandwidthint