J/ApJ/705/1481ivo://CDS.VizieR/J/ApJ/705/1481doi:10.26093/cds/vizier.17051481CDSDa Costa G.S.Held E.V.Saviane I.Gullieuszik M.2017-06-01T08:53:00Z2012-01-03T15:24:48ZCDS support team

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

cds-question@unistra.frchemical-abundancesglobular-star-clustersgiant-starsspectroscopyline-intensitiesradial-velocityIntermediate resolution spectra at the CaII triplet have been obtained for 55 candidate red giants in the field of the globular cluster M22 with the VLT/FORS2 instrument. Spectra were also obtained for a number of red giants in standard globular clusters to provide a calibration of the observed line strengths with overall abundance [Fe/H]. For the 41 M22 member stars that lie within the V-V_HB_ bounds of the calibration, we find an abundance distribution that is substantially broader than that expected from the observed errors alone. We argue that this broad distribution cannot be the result of differential reddening. Instead, we conclude that, as has long been suspected, M22 is similar to {omega} Cen in having an intrinsic dispersion in heavy element abundance. The observed M22 abundance distribution rises sharply to a peak at [Fe/H]~-1.9 with a broad tail to higher abundances: the highest abundance star in our sample has [Fe/H] ~-1.45dex. If the unusual properties of {omega} Cen have their origin in a scenario in which the cluster is the remnant nucleus of a disrupted dwarf galaxy, then such a scenario likely also applies to M22.2009ApJ...705.1481Dhttps://cdsarc.cds.unistra.fr/viz-bin/cat/J/ApJ/705/1481CatalogResearchIsServedByTAP VizieR generic serviceIsPreviousVersionOfJ/A+A/540/A27IsServedByConesearch servicerelated-toJ/ApJ/698/2048 : Abundances of red giants in {omega} Cen (Johnson+, 2009)J/ApJ/681/1505 : Abundances of red giants in {omega} Cen (Johnson+, 2008)J/ApJ/682/1217 : Abundances in red giants in 7 globular clusters (Kirby+,J/AJ/130/2140 : Abundances and velocities in globular clusters (Pritzl+,J/MNRAS/349/1278 : BVI photometry of M22 (Monaco+, 2004)J/A+A/373/899 : New variables in M22 globular cluster (Kaluzny+, 2001)J/ApJS/99/637 : Equivalent widths for 54 red giants (Norris+ 1995)J/PASP/107/32 : uvby-hk photometry in M22 (Anthony-Twarog+ 1995)J/ApJ/420/612 : Proper motions + radial velocities in M22 (Peterson+ 1994)J/A+A/540/A27 : RV & EWCAII of Galactic globular clusters (Saviane+, 2012)https://cds.unistra.fr/vizier-org/licences_vizier.htmlhttps://vizier.cds.unistra.fr/viz-bin/VizieR-2?-source=J/ApJ/705/1481https://vizier.iucaa.in/viz-bin/VizieR-2?-source=J/ApJ/705/1481http://vizieridia.saao.ac.za/viz-bin/VizieR-2?-source=J/ApJ/705/1481https://vizier.cds.unistra.fr/viz-bin/votable?-source=J/ApJ/705/1481https://vizier.iucaa.in/viz-bin/votable?-source=J/ApJ/705/1481http://vizieridia.saao.ac.za/viz-bin/votable?-source=J/ApJ/705/1481GETtext/xml+votablehttps://tapvizier.cds.unistra.fr/TAPVizieR/tapCone search capability for table J/ApJ/705/1481/stars (Stars observed in the globular clusters)https://vizier.cds.unistra.fr/viz-bin/conesearch/J/ApJ/705/1481/stars?https://vizier.iucaa.in/viz-bin/conesearch/J/ApJ/705/1481/stars?http://vizieridia.saao.ac.za/viz-bin/conesearch/J/ApJ/705/1481/stars?GETtext/xml+votable180.050000true245.93-26.5316670.0055555555555555566/12405 12943 28972 28973 31019 42076 42955https://cdsarc.cds.unistra.fr/viz-bin/moc/J/ApJ/705/1481?format=asciiOpticaldefaultJ/ApJ/705/1481/starsStars observed in the globular clustersrecnoRecord number assigned by the VizieR team. Should Not be used for identification.meta.recordintClusterCluster name (1)meta.id.parentcharNameSource identification (N_NNNNN) (2)meta.id;meta.maincharRAJ2000Hour of Right Ascension (J2000)pos.eq.ra;meta.mainDEJ2000Degree of Declination (J2000)pos.eq.dec;meta.mainHRVHeliocentric radial velocitykm/sspect.dopplerVeloc;pos.heliocentricintDelVDifferential magnitude from horizontal branch (V-V_HB_)magphot.mag;em.opt.VfloatW8542Equivalent width of CaII 8542{AA} line (3)0.1nmspect.line.eqWidthfloate_W8542Uncertainty in W8542 (3)0.1nmstat.errorfloatW8662Equivalent width of CaII 8662{AA} line (3)0.1nmspect.line.eqWidthfloate_W8662Uncertainty in W8662 (3)0.1nmstat.errorfloatW(Ca)Sum of W8542 and W8662 (3)0.1nmspect.line.eqWidthfloate_W(Ca)Uncertainty in W(Ca) (3)0.1nmstat.errorfloat