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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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Gözlemler ve gökölçümü verileri
| Takýmyýldýz: | Cennet Kusu |  
    | Sað Açýklýk: | 13h51m26.68s |  
    | Yükselim: | -73°08'37.4" |  
    | Görünürdeki Parlaklýk: | 7.109 |  
    
        | Uzaklýk: | 78.555 parsek |  
        
    
    | özdevim Sað Açýklýk: | 36.1 |  
    | özdevim Yükselim: | -8.5 |  
    | B-T magnitude: | 7.445 |  
    | V-T magnitude: | 7.137 |  
    
 
 
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