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The r+s CEMP stars and AGB supernovae. Maria Lugaro University of Utrecht (NL). r + s CE MP stars. -3.1 < [Fe/H] < -2.1. [Eu/Fe] > 1. 1.7 < [C/Fe] < 2.6. [Ba/Fe] > 1. Similarity in the chemical composition: an homogenous sample. (see, e.g., Jonsell et al. 2006 A&A).
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The r+s CEMP stars and AGB supernovae Maria Lugaro University of Utrecht (NL)
r+sCEMP stars -3.1 < [Fe/H] < -2.1 [Eu/Fe] > 1 1.7 < [C/Fe] < 2.6 [Ba/Fe] > 1 Similarity in the chemical composition: an homogenous sample. (see, e.g., Jonsell et al. 2006 A&A) 17 r+s CEMP stars and 9 formationscenarios: Radiative levitation A r-rich ISM and self-pollution Binary system out of r-rich ISM and AGB pollution Triple system with SN- and AGB-pollution Binary system with AGB- and 1.5 or e-capture SN-pollution Binary system with AGB- and AIC-pollution Binary system with only AGB-pollution A relation to blue stragglers? Origin from a common cloud of r+s stars
Zijlstra (2004) MNRAS: “the initial-final mass relation steepens at low Z, due to low mass-loss efficiency” Yields from AGB stars (Karakas & Lattanzio 2007) At [Fe/H]=-2.3: 2.8 C>N C<N Hot bottom burning r+s CEMP stars: C>N Wanajo et al. (2006), ApJ: the case of an 8-10 M companion
Conclusion: Let’s not forget hot bottom burning in relation to r+s CEMP stars