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Fig. 7.


[Sr/Ba] vs. [Ba/Fe] in normal very metal-poor stars in our Galaxy (blue filled circles), in the stars in the dwarf galaxy Sculptor (black open circles), and in Tuc II (blue open circles). The green open squares represent a sample of Galactic CEMP stars studied from high-resolution spectra. The black dotted line at [Sr/Ba] ≈ −0.5 represents the pure r-process production as observed for example in the EMP star CS 31082-001 (Cayrel et al. 2001; Hill et al. 2002) and the CEMP star CS 22892-52 (Sneden et al. 2000, 2003). The CEMP stars with a high value of [Ba/Fe] and a low value of [Sr/Ba] have been enriched in neutron-capture elements by the ejecta of an AGB. Many CEMP stars have the same range of [Sr/Ba] as the normal EMP stars. They are CEMP-no. The red star represents Pisces II 10694. It is very similar to the galactic C-rich giant CS 22949-037 (filled green square).

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