<?xml version="1.0" encoding="UTF-8"?><xml><records><record><source-app name="Biblio" version="7.x">Drupal-Biblio</source-app><ref-type>17</ref-type><contributors><authors><author><style face="normal" font="default" size="100%">Da Costa, G. S.</style></author><author><style face="normal" font="default" size="100%">Hatzidimitriou, D.</style></author></authors></contributors><titles><title><style face="normal" font="default" size="100%">Ca II Triplet Spectroscopy of Giants in Small Magellanic Cloud Star Clusters: Abundances, Velocities, and the Age-Metallicity Relation</style></title><short-title><style face="normal" font="default" size="100%">The Astronomical Journal</style></short-title></titles><keywords><keyword><style  face="normal" font="default" size="100%">Astrophysics</style></keyword><keyword><style  face="normal" font="default" size="100%">GALAXIES: ABUNDANCES</style></keyword><keyword><style  face="normal" font="default" size="100%">GALAXIES: INDIVIDUAL: NAME: SMALL MAGELLANIC CLOUD</style></keyword><keyword><style  face="normal" font="default" size="100%">GALAXIES: KINEMATICS AND DYNAMICS</style></keyword><keyword><style  face="normal" font="default" size="100%">GALAXIES: MAGELLANIC CLOUDS</style></keyword><keyword><style  face="normal" font="default" size="100%">galaxies: star clusters</style></keyword></keywords><dates><year><style  face="normal" font="default" size="100%">1998</style></year><pub-dates><date><style  face="normal" font="default" size="100%">1998/05/1</style></date></pub-dates></dates><urls><web-urls><url><style face="normal" font="default" size="100%">https://ui.adsabs.harvard.edu/abs/1998AJ....115.1934D</style></url></web-urls></urls><volume><style face="normal" font="default" size="100%">115</style></volume><pages><style face="normal" font="default" size="100%">1934 - 1945</style></pages><isbn><style face="normal" font="default" size="100%">0004-6256</style></isbn><language><style face="normal" font="default" size="100%">eng</style></language><abstract><style face="normal" font="default" size="100%">We have obtained spectra at the Ca ii triplet of individual red giants in seven Small Magellanic Cloud (SMC) star clusters whose ages range from ~4 to 12 Gyr. The spectra have been used to determine mean abundances for six of the star clusters to a typical precision of 0.12 dex. When combined with existing data for other objects, the resulting SMC age-metallicity relation is generally consistent with that for a simple model of chemical evolution, scaled to the present-day SMC mean abundance and gas mass fraction. Two of the clusters (Lindsay 113 and NGC 339), however, have abundances that are ~0.5 dex lower than that expected from the mean age-metallicity relation. It is suggested that the formation of these clusters, which have ages of ~5 Gyr, may have involved the infall of unenriched gas, perhaps from the Magellanic Stream. The spectra also yield radial velocities for the seven clusters. The resulting velocity dispersion is 16 +/- 4 km s^-1, consistent with those of the SMC planetary nebula and carbon star populations.</style></abstract></record></records></xml>