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The Draco dwarf in CDM and MOND

Ewa L. Lokas·Gary A. Mamon·Francisco Prada
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Abstract

We present interpretations of the line-of-sight velocity distribution of stars in the Draco dwarf spheroidal galaxy in terms of CDM and MOND assuming constant mass-to-light ratio and anisotropy. We estimate the two parameters by fitting the line-of-sight velocity dispersion and kurtosis profiles for stellar samples differing by a number of stars rejected as interlopers. The results of the fitting procedure for CDM, high mass-to-light ratio (131-141 solar units in V-band) and weakly tangential orbits, are similar for different samples, but the quality of the fit is much worse when fewer interlopers are removed. For MOND, the derived mass-to-light ratio (21 solar units) is too large to be explained by the stellar content of the galaxy.

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Ewa L. Lokas, Gary A. Mamon, Francisco Prada. 2005-09-02. The Draco dwarf in CDM and MOND. https://doi.org/10.1051/eas%3A2006056

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