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  • LIGHT, ALPHA, AND Fe-PEAK E...
    Johnson, Christian I; Rich, R Michael; Kobayashi, Chiaki; KUNDER, ANDREA; Koch, Andreas

    The Astronomical journal, 10/2014, Letnik: 148, Številka: 4
    Journal Article

    We present radial velocities and chemical abundances of O, Na, Mg, Al, Si, Ca, Cr, Fe, Co, Ni, and Cu for a sample of 156 red giant branch stars in two Galactic bulge fields centered near (l, b) = (+ 5.25,-3.02) and (0,-12). The (+ 5.25,-3.02) field also includes observations of the bulge globular cluster NGC 6553. However, we only selected a subset of the original observations that included spectra with both high S/N and that did not show strong TiO absorption bands. This work extends previous analysis of this data set beyond Fe and the alpha -elements Mg, Si, Ca, and Ti. For most elements, the NGC 6553 stars exhibit abundance trends nearly identical to comparable metallicity bulge field stars. However, the star-to-star scatter and mean Na/Fe ratios appear higher in the cluster, perhaps indicating additional self-enrichment.