The Field of Streams: Sagittarius and its Siblings

V. Belokurov; D. B. Zucker; N. W. Evans; G. Gilmore; S. Vidrih; D. M. Bramich; H. J. Newberg; R. F. G. Wyse; M. J. Irwin; M. Fellhauer; P. C. Hewett; N. A. Walton; M. I. Wilkinson; N. Cole; B. Yanny; C. M. Rockosi; T. C. Beers; E. F. Bell; J. Brinkmann; Z. Ivesic; R. Lupton

doi:10.1086/504797

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The Field of Streams: Sagittarius and its Siblings

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Abstract

We use Sloan Digital Sky Survey (SDSS) Data Release 5 (DR5) u,g,r,i,z photometry to study Milky Way halo substructure in the area around the North Galactic Cap. A simple color cut (g-r < 0.4) reveals the tidal stream of the Sagittarius dwarf spheroidal, as well as a number of other stellar structures in the field. Two branches (A and B) of the Sagittarius stream are clearly visible in an RGB-composite image created from 3 magnitude slices, and there is also evidence for a still more distant wrap behind the A branch. A comparison of these data with numerical models suggests that the shape of the Galactic dark halo is close to spherical.

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V. Belokurov, D. B. Zucker, N. W. Evans, G. Gilmore, S. Vidrih, D. M. Bramich, H. J. Newberg, R. F. G. Wyse, M. J. Irwin, M. Fellhauer, P. C. Hewett, N. A. Walton, M. I. Wilkinson, N. Cole, B. Yanny, C. M. Rockosi, T. C. Beers, E. F. Bell, J. Brinkmann, Z. Ivesic, R. Lupton. 2006-05-01. The Field of Streams: Sagittarius and its Siblings. https://doi.org/10.1086/504797

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