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arXiv · 0709.3000

Cool carbon stars in the halo: new very red or distant objects

N. Mauron·K. S. Gigoyan·T. R. Kendall
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Abstract

The goal of this paper is to present and analyse a new sample of cool carbon (C)stars located in the halo. Twenty three new C stars were discovered. Spectra are typical of N-type stars with C2 and CN bands and sometimes Halpha in emission. ... Four objects are particularly red with J-K > 3, with 2 located at more than 5 kpc. from the Galactic plane. Eight additional objects with similar properties are found in the literature and our previous works. These 12 C stars could be useful to study mass loss at low metallicity. Two objects are at distances of 95 and 110 kpc. They are located in the region with galactocentric Z < -60 kpc in which the model of Law et al. predicts the Sgr stream to have a loop. (Abstact abridged)

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N. Mauron, K. S. Gigoyan, T. R. Kendall. 2007-09-19. Cool carbon stars in the halo: new very red or distant objects. https://doi.org/10.1051/0004-6361:20078181

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