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Are "dwarf" Ellipticals genuine Ellipticals?

Helmut Jerjen·Bruno Binggeli
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Abstract

We review the systematic properties of ``dwarf'' elliptical (dE) galaxies, focussing on the relation between ``normal'' and ``dwarf'' ellipticals. In recent years, this relation has been described as ``dichotomy'' -- based essentially on a discontinuity in central surface brightness. We show that, outside of 300 pc from the centre, the Sérsic profile parameters vary continuously from ``normal'' to ``dwarf'' ellipticals. The ``dichotomy'' is indeed restricted to the very central part, where differences also exist among ``normal'' ellipticals (E). Bright, nucleated dE's closely resemble ``normal'' E's also in their clustering and flattening properties. They may be genuine ellipticals, having no present-day late-type dwarf precursor from which they could have been manufactured. The non-nucleated dE's ("dwarf spheroidals") may be a different breed.

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Helmut Jerjen, Bruno Binggeli. 1997-01-29. Are "dwarf" Ellipticals genuine Ellipticals?. https://arxiv.org/abs/astro-ph/9701221

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