Implications for dwarf spheroidal mass content from interloper removal
نویسندگان
چکیده
We use Diaferio (1999)'s caustic method to identify the member stars of five dwarf spheroidal (dSph) galaxies of the Milky Way, the smallest dark matter (DM) dominated systems in the Universe. We show that, after successful rejection of interlopers, the line-of-sight velocity dispersions are substantially smaller than previous calculations. With this, we use Jeans modelling to show that the DM content interior to 300 pc appears to increase with satellite luminosity. Moreover, if we assume that MOND provides the true law of gravity, a correct identification of interlopers implies that these dSphs have reasonable values for their mass-to-light ratios, alleviating one of the claimed problems of MOND.
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