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Structure of the Draco Dwarf Spheroidal Galaxy

Slawomir Piatek·Carlton Pryor·Taft E. Armandroff·Edward W. Olszewski
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Abstract

This article studies the structure of the Draco dwarf spheroidal galaxy with an emphasis on the question of whether the spatial distribution of its stars has been affected by the tidal interaction with the Milky Way, using R- and V-band CCD photometry for eleven fields. The article reports coordinates for the center, a position angle of the major axis, and the ellipticity. It also reports the results of searches for asymmetries in the structure of Draco. These results, and searches for a ``break'' in the radial profile and for the presence of principal sequences of Draco in a color-magnitude diagram for regions more than 50 arcmin from the center, yield no evidence that tidal forces from the Milky Way have affected the structure of Draco.

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Slawomir Piatek, Carlton Pryor, Taft E. Armandroff, Edward W. Olszewski. 2002-01-17. Structure of the Draco Dwarf Spheroidal Galaxy. https://doi.org/10.1086/339698

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