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RR Lyrae search and stellar populations study in Canis Major: Preliminary Results

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

We present preliminary results of a RR Lyrae star search and stellar populations study performed in the Canis Major overdensity, spanning an area of 8.35sq deg. The observations were made in R and V bands, with the QUEST camera installed in the 1m Jurgen Stock Telescope, at the Venezuela National Observatory. The resulting Hess diagram shows a possible, but weak, red giant branch and no obvious horizontal branch, red clump or main sequence turnoff. After a multi--epoch photometric search, 6 RR Lyrae stars were confirmed with further observations obtained at the 1.0 and 1.3m telescopes of the SMARTS consortium at CTIO. Of these confirmed RR Lyrae stars, 5 have heliocentric distances between 5 and 7 kpc. Confirmation of their physsical association with the Canis Major system awaits for a study of their radial velocities.

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Cecilia E. Mateu, A. Katherina Vivas, Robert Zinn, Lissa Miller. 2005-04-14. RR Lyrae search and stellar populations study in Canis Major: Preliminary Results. https://arxiv.org/abs/astro-ph/0504333

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