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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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Сазвежђа: | Часовник |
Ректацензија: | 03h10m22.63s |
Deклинација: | -63°15'14.0" |
Apparent магнитуда: | 8.217 |
Даљина: | 181.818 parsecs |
Proper motion RA: | 2.7 |
Proper motion Dec: | -11.7 |
B-T magnitude: | 8.599 |
V-T magnitude: | 8.249 |
Каталог и designations:
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