The classifications compare roughly as follows

The classifications compare roughly as follows - Galaxy...

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The classifications compare roughly as follows, based on an early Annual Reviews article: Property/Class Regular (Early) Intermediate Irregular (Late) Zwicky type Compact Medium-Compact Open Bautz-Morgan type I, I-II, II (II), II-III (II-III), III Rood-Sastry type cD,B, (L,C) (L),(F),(C) (F), I Content Elliptical-rich Spiral-poor Spiral-rich E:S0:S ratio 3:4:2 1:4:2 1:2:3 Symmetry Spherical Intermediate Irregular shape Central concentration High Moderate Very little Central profile Steep Intermediate Flat Mass segregation? Marginal Marginal None Radio emission? 50% 50% 20% X-ray luminosity High Intermediate Low Examples A2199, Coma A194,A539 Virgo, A1228 Is the implied sequence one of total mass, mass concentration, or status of dynamical evolution? These are probably correlated too. Some additional properties of clusters vary with concentration (or extent of relaxation or richness, all of which are related). These include:
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Unformatted text preview: Galaxy content: the fraction of E/S0 galaxies depends on local galaxy density (Dressler 1980 ApJ 236, 351) and thus changes markedly from the outskirts to a cluster core (see the environmental-impact lecture . Only loose or subcluster environments have many spirals. As we've already seen, this changes with cosmic epoch in the Butcher-Oemler effect. Symmetry: the most concentrated clusters are most symmetric and regular, approaching in some cases an equipartition distribution. One may seek substructure in position or velocity space. Mass segregation: If the cluster evolves far enough dynamically, energy will be equally distributed among members, so that the more massive ones move more slowly and sink to the center. There is some evidence for this effect in a few clusters....
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