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arXiv · 1405.1441

The 13C-Pocket Structure in AGB Models: Constraints from Zirconium Isotope Abundances in Single Mainstream SiC Grains

Nan Liu·Roberto Gallino·Sara Bisterzo·Andrew M. Davis·Michael R. Savina·Michael J. Pellin
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Abstract

We present postprocess AGB nucleosynthesis models with different $^{13}$C-pocket internal structures to better explain zirconium isotope measurements in mainstream presolar SiC grains by Nicolussi et al. (1997) and Barzyk et al. (2007). We show that higher-than-solar $^{92}$Zr/$^{94}$Zr ratios can be predicted by adopting a $^{13}$C-pocket with a flat $^{13}$C profile, instead of the previous decreasing-with-depth $^{13}$C profile. The improved agreement between grain data for zirconium isotopes and AGB models provides additional support for a recent proposal of a flat $^{13}$C profile based on barium isotopes in mainstream SiC grains by Liu et al. (2014).

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Nan Liu, Roberto Gallino, Sara Bisterzo, Andrew M. Davis, Michael R. Savina, Michael J. Pellin. 2014-05-06. The 13C-Pocket Structure in AGB Models: Constraints from Zirconium Isotope Abundances in Single Mainstream SiC Grains. https://doi.org/10.1088/0004-637x/788/2/163

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