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تسجيل مستخدم جديدAbout Synchronized Globular Cluster Formation over Supra-galactic Scales
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Juan C. Forte
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Observational and theoretical arguments support the idea that violent events connected with $AGN$ activity and/or intense star forming episodes have played a significant role in the early phases of galaxy formation at high red shifts. Being old stellar systems, globular clusters seem adequate candidates to search for the eventual signatures that might have been left by those energetic phenomena. The analysis of the colour distributions of several thousands of globular clusters in the Virgo and Fornax galaxy clusters reveals the existence of some interesting and previously undetected features. A simple pattern recognition technique, indicates the presence of colour modulations, distinctive for each galaxy cluster. The results suggest that the globular cluster formation process has not been completely stochastic but, rather, included a significant fraction of globulars that formed in a synchronized way and over supra-galactic spatial scales.
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An analysis of globular cluster systems associated with galaxies included in the Virgo and Fornax HST Advanced Camera Surveys reveals distinct (g-z) colour modulation patterns. These features appear on composite samples of globular clusters and, most
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Globular clusters are compact, gravitationally bound systems of up to a million stars. The GCs in the Milky Way contain some of the oldest stars known, and provide important clues to the early formation and continuing evolution of our Galaxy. More ge
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