Mass-to-light ratios in early-type galaxies and the dark matter content

M. Capaccioli; N. R. Napolitano; M. Arnaboldi

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arXiv · astro-ph/0211323

Mass-to-light ratios in early-type galaxies and the dark matter content

M. Capaccioli·N. R. Napolitano·M. Arnaboldi

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Abstract

The distribution of the radial trends of the mass-to-light ratios (M/L) within an assorted sample of early-type galaxies is discussed. Three classes of galaxies are identified according to their M/L gradients. Two such classes are characterized by the presence or by the absence of a radial gradient of the dark-matter (DM) distribution. A third class contains objects which are likely undergoing interaction; they exhibit steep M/L gradients which are possibly the result of a wrong assumption on their equilibrium conditions. Finally, a possible correlation between DM content and morphological types is briefly discussed.

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M. Capaccioli, N. R. Napolitano, M. Arnaboldi. 2002-11-14. Mass-to-light ratios in early-type galaxies and the dark matter content. https://arxiv.org/abs/astro-ph/0211323

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