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تسجيل مستخدم جديدAn Empirical View to the Early Chemical Evolution of Bulge/Disk Galaxies
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تأليف
Alvio Renzini
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Scaling from the empirical metal yield as measured in clusters of galaxies, it is inferred that early in the evolution of the Galaxy the bulge stellar population has produced $sim 10^9msun$ of metals, at least 5 times more than the total metal content of the bulge today. It is argued that an early galactic wind from the starbursting bulge has pre-enriched a vast region around it, with these metals being able to enrich to $sim 1/10$ solar of order of $5times 10^{11}msun$ of pristine material. From the empirical evidence that bulges come before disks, it is inferred that the Milky Way disk formed out of this pre-enriched material, which accounts for the scarcity of metal poor stars in the solar neighborhood, the so-called `G-Dwarf Problem. High redshift observations are now becoming able to efficiently explore the $1.2lsim zlsim 3$ region of the universe, when disk formation and morphological differentiation may have taken place.
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