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Cool carbon stars in the halo II. A study of 25 new objects

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

We present new results from an ongoing survey of carbon-rich asymptotic giant (AGB) stars in the halo of our Galaxy. After selecting candidates primarily through their 2MASS colours, slit spectroscopy was achieved at the ESO NTT telescope. Twenty-one new AGB carbon stars were discovered, increasing the total of presently known similar AGB C stars to about 120. A further four were observed again in order to confirm their carbon-rich nature and measure radial velocities. Two main findings emerge from this work. First, we found a C star located at about 130 kpc from the Sun and at b = -62 degrees. This distant star is remarkably close (5 kpc) to the principal plane of the Stream of the Sagittarius dwarf galaxy, and is likely to be a tracer of a distant poorly populated southern warp of the Stream. etc etc

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N. Mauron, T. R. Kendall, K. Gigoyan. 2005-06-22. Cool carbon stars in the halo II. A study of 25 new objects. https://doi.org/10.1051/0004-6361%3A20052820

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