Ýçindekiler
Görüntüler
Resim Yükleyin
DSS Images Other Images
Ýlgili Makaleler
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.
| Variable and Potential Variable Stars in the Bright Star Catalogue Not Available
|
Yeni bir Makale Öner
Ýlgili Baðlantýlar
Yeni Bir Baðlantý Öner
sonraki gruplarýn üyesi:
|
Gözlemler ve gökölçümü verileri
Takýmyýldýz: | Karina |
Sað Açýklýk: | 07h06m30.71s |
Yükselim: | -57°46'42.4" |
Görünürdeki Parlaklýk: | 7.71 |
Uzaklýk: | 172.414 parsek |
özdevim Sað Açýklýk: | -1.1 |
özdevim Yükselim: | 1.9 |
B-T magnitude: | 7.979 |
V-T magnitude: | 7.733 |
Kataloglar ve belirtme:
|