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Reaching to the Edge of the Milky Way Halo with SDSS

Z. Ivezic·R. H. Lupton·D. Schlegel·V. Smolcic·D. Johnston·J. E. Gunn·G. R. Knapp·M. A. Strauss·C. M. Rockosi
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Abstract

We discuss a sample of over 3000 candidate RR Lyrae stars selected by various methods using Sloan Digital Sky Survey data for about 1000 deg^2 of sky. These stars probe the halo structure out to ~100 kpc from the Galactic center. Their spatial and radial velocity distributions are very inhomogeneous, with the most prominent features tracing the Sgr dwarf tidal stream. Outside the Sgr dwarf tidal stream, the spatial distribution in the 5-60 kpc range of Galactocentric radius R is well described by an R^{-3} power law.

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Z. Ivezic, R. H. Lupton, D. Schlegel, V. Smolcic, D. Johnston, J. E. Gunn, G. R. Knapp, M. A. Strauss, C. M. Rockosi. 2003-09-02. Reaching to the Edge of the Milky Way Halo with SDSS. https://arxiv.org/abs/astro-ph/0309074

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