Phase-space models of the dwarf spheroidals★
نویسندگان
چکیده
منابع مشابه
Dark Matter in Dwarf Spheroidals I: Models
This paper introduces a new two-parameter family of dwarf spheroidal (dSph) galaxy models. The mass distribution has a Plummer profile and falls like R−4 in projection in agreement with the star-count data. The first free parameter controls the velocity anisotropy, the second controls the dark matter content. The dark matter distribution can be varied from one extreme of mass-follows-light thro...
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The spatial distributions of the most recently discovered ultra faint dwarf satellites around the Milky Way and the Andromeda galaxy are compared to the previously reported discs-of-satellites (DoS) of their host galaxies. In our investigation we pay special attention to the selection bias introduced due to the limited sky coverage of SDSS. We find that the new Milky Way satellite galaxies foll...
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We consider the problem of determining the structure of the dark halo of nearby dwarf spheroidal galaxies (dSphs) from the spherical Jeans equations. Whether the dark halos are cusped or cored at the centre is an important strategic problem in modern astronomy. The observational data comprise the line-of-sight velocity dispersion of a luminous tracer population. We show that when such data are ...
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ژورنال
عنوان ژورنال: Monthly Notices of the Royal Astronomical Society
سال: 2010
ISSN: 0035-8711
DOI: 10.1111/j.1365-2966.2010.17715.x