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Stroemgren photometry of F- and G-type stars brighter than V = 9.6. I. UVBY photometry
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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: | Gru |
| Ascensione retta: | 22h15m18.04s |
| Declinazione: | -52°42'04.5" |
| Magnitudine apparente: | 7.911 |
| Distanza: | 242.131 parsec |
| Moto proprio RA: | 14.3 |
| Moto proprio Dec: | -2.8 |
| B-T magnitude: | 8.769 |
| V-T magnitude: | 7.982 |
Cataloghi e designazioni:
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