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Searching for RR Lyrae stars in the Canis Major Overdensity

Cecilia Mateu·A. Katherina Vivas·Robert Zinn·Lissa Miller·.
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Abstract

The Canis Major overdensity (CMa) was initially proposed to be the remnant of a tidally disrupting dSph galaxy. Since its nature is still subject of debate, the goal of the present work was to conduct a large-scale RR Lyrae survey in CMa, in order to see if there is an overdensity of these stars. The survey spans a total area of ~34 sq. deg. with observations in V and R filters, made with the 1.0m Jurgen Stock Schmidt telescope at the National Astronomical Observatory of Venezuela. Current results in a subregion, including spectroscopic observations, show that the small number of RR Lyrae stars found can be accounted for by the halo and thick disk components of our Galaxy.

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Cecilia Mateu, A. Katherina Vivas, Robert Zinn, Lissa Miller, .. 2007-02-06. Searching for RR Lyrae stars in the Canis Major Overdensity. https://doi.org/10.1017/s1743921307008459

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