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Paper: Dark Matter in Groups and Clusters of Galaxies
Volume: 209, Small Galaxy Groups, IAU Colloquium 174
Page: 360
Authors: Einasto, Jaan; Einasto, Maret
Abstract: We compare the characteristics of stellar populations with those of dark halos. Dark matter around galaxies, and in groups, clusters and voids is discussed. Modern data suggest that the overall density of matter in the Universe is ΩM = 0.3 +/- 0.1, about 80% of this matter is non-baryonic dark matter, and about 20% is baryonic, mostly in the form of hot intra-cluster and intragroup gas, the rest in stellar populations of galaxies. All bright galaxies are surrounded by dark matter halos of external radii 200 - 300 kpc; halos consist mostly of non-baryonic matter with some mixture of hot gas. The Universe is dominated by dark energy (cosmological constant) term. Dark matter dominates in the dynamical evolution of galaxies in groups and clusters.
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