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The chemical evolution of the solar neighborhood. I - A bias-free reduction technique and data sample The possible ways of measuring the age-metallicity relation for thegalactic disk in the neighborhood of the sun are discussed. It is shownthat the use of a field star sample chosen on the basis of effectivetemperature introduces a bias which results in a monotonic increase inthe metal abundance of the disk with time. However, if theage-metallicity relation for the disk can be shown to satisfy certaincriteria, the bias introduced in such a sample can be neglected: thegalactic disk apparently satisfies the criteria. It is concluded that asample analyzed through the use of uvby and H(beta) photometry inconjunction with a self-consistent set of theoretical isochronesprovides the least biased, most accurate estimate of the age-metallicityrelation for the disk.
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Osservazione e dati astrometrici
Costellazione: | Altare |
Ascensione retta: | 17h51m05.40s |
Declinazione: | -54°15'54.7" |
Magnitudine apparente: | 8.316 |
Distanza: | 186.567 parsec |
Moto proprio RA: | 4.6 |
Moto proprio Dec: | -48 |
B-T magnitude: | 8.769 |
V-T magnitude: | 8.354 |
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