Carlos Vera-Ciro, Amina Helmi
We propose a new model for the dark matter halo of the Milky Way that fits the properties of the stellar stream associated with the Sagittarius dwarf galaxy. Our dark halo is oblate with q = 0.9 for r < 10 kpc, and follows the Law & Majewski (2010) model at large radii, the transition between these regimes occurring at ~30 kpc. The outer halo can be made mildly triaxial, with minor-to-major axis ratio (c/a)_\Phi = 0.8 and intermediate-to-major axis ratio (b/a)_\Phi = 0.9, if the effect of the Large Magellanic Cloud is taken into account. Therefore this new model takes into account the flattening induced by the presence of the Galactic disk and is also more consistent with cosmological expectations.
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http://arxiv.org/abs/1304.4646
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