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The heavy-element abundances of AGB stars and the angular momentum conservation model of wind accretion for barium stars

Y. C. Liang·G. Zhao·B. Zhang
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Abstract

Adpoting new s-process nucleosynthesis scenario and branch s-process path, we calculate the heavy-element abundances and C/O ratio of solar metallicity 3M_sun TP-AGB stars. The evolutionary sequence from M to S to C stars of AGB stars is explained naturally by the calculated results. Then combining the angular momentum conservation model of wind accretion with the heavy-element abundances on the surface of TP-AGB stars, we calculate the heavy-element overabundances of barium stars via successive pulsed accreting and mixing. Our results support that the barium stars with longer orbital period, P>1600 days, form through wind accretion scenario.

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Y. C. Liang, G. Zhao, B. Zhang. 2000-11-06. The heavy-element abundances of AGB stars and the angular momentum conservation model of wind accretion for barium stars. https://arxiv.org/abs/astro-ph/0011118

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