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Mass-to-light ratios of ellipticals in LCDM

N. R. Napolitano·the PN. S team
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Abstract

We use the mass-to-light gradients in early-type galaxies to infer the global dark matter fraction, f_d=M_d/M_*, for these systems. We discuss implications about the total star formation efficiency in dark-matter halos and show that the trend of $f_{\rm d}$ with mass produces virial mass-to-light ratios which are consistent with semi-analitical models. Preliminary kurtosis analysis of the quasi-constant M/L galaxies in Romanowsky et al. seems at odd with Dekel et al. simulations.

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N. R. Napolitano, the PN. S team. 2005-10-19. Mass-to-light ratios of ellipticals in LCDM. https://doi.org/10.1051/eas%3A2006059

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