Sbordone, L., Hansen, C. J., Monaco, L., Cristallo, S., Bonifacio, P., Caffau, E., et al. (2020). A wide angle view of the Sagittarius dwarf spheroidal galaxy II. A CEMP-r/s star in the Sagittarius dwarf spheroidal galaxy. Astron. Astrophys., 641, 9 pp.
Abstract: We report on the discovery and chemical abundance analysis of the first CEMP-r/s star detected in the Sagittarius dwarf spheroidal galaxy (Sgr dSph) by means of UVES high-resolution spectra. The star, found in the outskirts of Sgr dSph, along the major axis of the main body, is a moderately metal-poor giant (T-eff=4753 K, log g=1.75, [Fe/H] = -1.55) with [C/Fe] = 1.13, placing it in the so-called “high-carbon band”, and strong s-process and r-process enrichment ([Ba/Fe] = 1.4, [Eu/Fe] = 1.01). Abundances of 29 elements from C to Dy were obtained. The chemical pattern appears to be best fitted by a scenario where an r-process pollution event pre-enriched the material out of which the star was born as secondary in a binary system whose primary evolved through the AGB phase, providing C- and s-process enrichment.
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