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تسجيل مستخدم جديدOpen Clusters in the log Age vs. M_V plane
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M. Bellazzini
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In the log Age vs. integrated absolute magnitude (M_V) plane, the open clusters of the Milky Way form a well-defined band parallel to theoretical sequences decribing the passive evolution of Simple Stellar Populations and display a pretty sharp upper threshold in mass (M ~ 2X 10^4 M_{sun}) over a 4 dex range of ages.
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