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The galactic disc age-metallicity relation

Y. K. Ng·G. Bertelli·G. Carraro·L. Portinari
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Abstract

New ages are computed for stars in the Solar Neighbourhood from the Edvardsson et al. (1993) data set. Distances derived from the Hipparcos parallaxes were adopted to obtain reliable ages (uncertainty less than 12%) for a subset of stars. There is no apparent age-metallicity relation for stars with an age less than 10 Gyr. Only if we consider older stars a slope of ~0.07 dex/Gyr appears. This relation is compared with those obtained from other methods, i.e. galactic open clusters, stellar population synthesis (star counts), and chemical evolution models.

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Y. K. Ng, G. Bertelli, G. Carraro, L. Portinari. 1997-09-18. The galactic disc age-metallicity relation. https://arxiv.org/abs/astro-ph/9709182

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