Galaxies. Группа авторов

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Galaxies - Группа авторов


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brightness as a function of galactocentric distance, with no inflections or other apparent structure. Type E+ galaxies are considered as “late” ellipticals showing some traces of structure. The structure can be in the form of a subtle lens, a feature that when more apparent is seen to have a shallow brightness gradient interior to a sharp edge (Sandage 1961; Kormendy 1979). In the Third Reference Catalogue of Bright Galaxies (RC3; de Vaucouleurs et al. 1991), the E+ classification was also applied to brightest cluster members having a shallow brightness gradient (or an apparent extended envelope) in the outer regions. In the Morgan (1958) classification system, such objects are classified as type cD. Examples of E and E+ galaxies are shown in Figures 1.5 and 1.6. Other aspects of E galaxy morphology include the following:

Photos depict E plus galaxies are generally elliptical galaxies with very subtle traces of structure, usually in the form of a lens, a feature with a shallow brightness gradient interior to a sharp edge. Schematic illustration of examples of dusky and boxy elliptical galaxies. Schematic illustration of twelve examples of dust-lane early-type galaxies, including ellipticals and S0s.

      The fundamental plane of E galaxies: Elliptical galaxies are characterized by a well-defined interconnectedness of their physical parameters. In the three-dimensional space defined by the parameters Re, the effective radius that transmits half the total luminosity; Ie, the average surface brightness within this radius; and σo, the central velocity dispersion,


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