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Influence of Hipparcos on Hyades age estimates from three binary systems

E. Lastennet·D. Valls-Gabaud·T. Lejeune·E. Oblak
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Abstract

Three independent sets of stellar theoretical models are tested with well-detached systems of the Hyades open cluster: 51 Tau, V818 Tau, and $θ^2$ Tau. The choice of these objects is discussed and a statistical method is described and applied to the colour-magnitude diagram (CMD) of the selected stars, giving rise to contour levels in the metallicity-age plane. The effects of the Hipparcos parallaxes on these confidence regions, with influence on both age and metallicity, are studied for the V818 Tau system through a comparison with very accurate but older orbital parallaxes. Finally, theoretical simultaneous age-metallicity estimates are given for the three binaries and compared with observational constraints.

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E. Lastennet, D. Valls-Gabaud, T. Lejeune, E. Oblak. 1999-07-30. Influence of Hipparcos on Hyades age estimates from three binary systems. https://arxiv.org/abs/astro-ph/9907443

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