J/A+A/580/A121ivo://CDS.VizieR/J/A+A/580/A121doi:10.26093/cds/vizier.35800121CDSVasquez S.Zoccali M.Hill V.Gonzalez O.A.Saviane I.Rejkuba M.,Battaglia G.2015-12-29T11:39:25Z2015-08-19T11:08:48ZCDS support team

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

cds-question@unistra.frmilky-way-galaxyk-starsspectroscopymetallicityWe present a new calibration of the calcium II triplet equivalent widths versus [Fe/H], constructed upon K giant stars in the Galactic bulge. This calibration will be used to derive iron abundances for the targets of the GIBS survey, and is in general especially well suited for solar and supersolar metallicity giants, which are typical of external massive galaxies. To obtain the calibration, about 150 bulge K giants were observed with the GIRAFFE spectrograph at the VLT with a resolution of R~20000 and at R~6000. In the first case, the spectra allowed us to directly determine the Fe abundances from several unblended Fe lines, deriving what we call here high-resolution [Fe/H] measurements. The low-resolution spectra allowed us to measure equivalent widths of the two strongest lines of the near-infrared calcium II triplet at 8542 and 8662{AA}. By comparing the two measurements, we derived a relation between calcium equivalent widths and [Fe/H] that is linear over the metallicity range probed here, -1<[Fe/H]<+0.7. By adding a small second-order correction based on literature globular cluster data, we derived the unique calibration equation [Fe/H]_CaT_=-3.150+0.432W'+0.006W'^2^, with an rms dispersion of 0.197dex, valid across the whole metallicity range -2.3<[Fe/H]<+0.7.2015A&A...580A.121Vhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/A+A/580/A121CatalogResearchIsServedByTAP VizieR generic serviceIsServedByConesearch servicehttps://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/A+A/580/A121https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/A+A/580/A121http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/A+A/580/A121https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/A+A/580/A121https://vizier.iucaa.in/viz-bin/votable?-source=J/A+A/580/A121http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/A+A/580/A121GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/A+A/580/A121/table2 (Calcium triplet metallicity calibration for bulge stars)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/A+A/580/A121/table2?https://vizier.iucaa.in/viz-bin/conesearch/J/A+A/580/A121/table2?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/A+A/580/A121/table2?GETtext/xml+votable180.050000true271.0736667-30.008250.0055555555555555566/28778https://cdsarc.cds.unistra.fr/viz-bin/moc/J/A+A/580/A121?format=asciiOpticaldefaultJ/A+A/580/A121/table2Calcium triplet metallicity calibration for bulge starsrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintField[RGB RC] Bulge field: Red Giant Branch or Red Clumpmeta.id;obs.fieldcharID[44560/596502] Identification numbermeta.id;meta.mainintRAJ2000Right ascension (J2000)pos.eq.ra;meta.mainDEJ2000Declination (J2000)pos.eq.dec;meta.maindKmag[-1.77/0.28] K-K_RC_ magnitude differencemagphot.mag;em.IR.KfloatEW2Equivalent width at 8542.09{AA}0.1nmspect.line.eqWidthfloate_EW2Uncertainty for EW20.1nmstat.errorfloatEW3Equivalent width at 8662.14{AA}0.1nmspect.line.eqWidthfloate_EW3Uncertainty for EW30.1nmstat.errorfloat[Fe/H][-1.44/0.62] High resolution metallicitylog(Sun)phys.abund.Fefloate_[Fe/H][0.08/0.49] Uncertainty for [Fe/H]log(Sun)stat.error;phys.abund.Fefloat