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Structural properties of dwarf elliptical galaxies and the connection with (ordinary) elliptical galaxies

Alister W. Graham
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Abstract

This article reviews the popular reasons for the belief that dwarf elliptical galaxies and (ordinary) elliptical galaxies are distinct and separate species. They include: light-profile shape (or similarly image concentration); the magnitude-central surface brightness diagram; the magnitude-effective surface brightness diagram (or similarly the magnitude-effective radius diagram); and the Fundamental Plane. It is shown how a continuous trend between luminosity and a) light-profile shape, and b) central surface brightness (until the onest of core formation at M_B ~ -20.5 mag, results in a unification of the dwarf elliptical and (ordinary) elliptical galaxies. Neither the above four reasons, nor the luminosity function (at least in the Virgo cluster) provide evidence for a division at M_B = -18 mag between the dwarf elliptical and (ordinary) elliptical galaxies. Instead, they appear to be continuous extensions of each other.

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Alister W. Graham. 2005-05-20. Structural properties of dwarf elliptical galaxies and the connection with (ordinary) elliptical galaxies. https://doi.org/10.1017/s1743921305003960

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