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تسجيل مستخدم جديدMetallicity distribution of Omega Cen Red Giants based on the Stroemgren m1 metallicity index
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We adopted uvby Stroemgren photometry to investigate the metallicity distribution of Omega Cen Red Giant (RG) stars. We provided a new empirical calibration of the Stroemgren m1 = (v-b)-(b-y) metallicity index based on cluster stars. The new calibration has been applied to a sample of Omega Cen RGs. The shape of the estimated metallicity distribution is clearly asymmetric, with a sharp cut-off at low metallicities ([Fe/H] < -2.0) and a metal-rich tail up to [Fe/H] ~ 0.0. Two main metallicity peaks have been identified, around [Fe/H] ~ -1.9 and -1.3 dex, and a metal-rich shoulder at ~ 0.2 dex.
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