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Chemical abundances of RGB-Tip stars in the Sagittarius dwarf Spheroidal galaxy

Lorenzo Monaco
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Abstract

We present preliminary iron abundances and $α$ element (Ca, Mg) abundance ratios for a sample of 22 Red Giant Branch (RGB) Stars in the Sagittarius dwarf spheroidal galaxy (Sgr), selected near the RGB-Tip. The sample is representative of the Sgr dominant population. The mean iron abundance is [Fe/H]=-0.49. The $α$ element abundance ratios are slightly subsolar, in agreement with the results recently prensented by Bonifacio et al.(2004, A&A, 414, 503).

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Lorenzo Monaco. 2004-10-29. Chemical abundances of RGB-Tip stars in the Sagittarius dwarf Spheroidal galaxy. https://arxiv.org/abs/astro-ph/0410749

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