We analyse the light elements C, N, O, Na and Mg, as well as the two s-process indicators, (where ls = is the the light-s peak at N = 50 and hs = the heavy-s peak at N = 82) and. The secondary observed low-mass companion became CEMP-s by the mass transfer of C- and s-rich material from the primary AGB. The s-process enhancement detected in these objects is associated with binary systems: the more massive companion evolved faster through the thermally pulsing AGB phase (TP-AGB), synthesizing s-elements in the inner He intershell, which are partly dredged up to the surface during the third dredge-up (TDU) episode. High-resolution spectroscopic observations of 100 metal-poor carbon and s-rich stars (CEMP-s) collected from the literature are compared with the theoretical nucleosynthesis models of the asymptotic giant branch (AGB) presented in Paper I (M AGB ini= 1.3, 1.4, 1.5, 2 M ⊙, - 3.6 ≲ ≲- 1.5).
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