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cD Galaxies
•Kormendy (1982) distinguishes these from being merely giant ellipticals.
–Extensive stellar envelope up to 100 kpc
–Only in regions of enhanced galaxy density (a factor of 100 denser than the average)
–Mutiple nuclei in 25-50% of cDs (a very rare thing)
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•Regular cD clusters are systems that have relaxed into dynamical equilibirum.
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