Dependence of S-process Nucleosynthesis in Massive Stars on Triple-alpha and C(α, Γ)o Reaction Rate Uncertainties
نویسندگان
چکیده
We have studied the sensitivity of s-process nucleosynthesis in massive stars to ±2σ variations in the rates of the triple-α and C(α, γ)O reactions. We simulated the evolution of massive stars from H-burning through Fe-core collapse, followed by a supernova explosion. We found that: the production factors of s-process nuclides between Fe and Zr change strongly with changes in the He burning reaction rates; using the Lodders (2003) solar abundances rather than those of Anders & Grevesse (1989) reduces s-process nucleosynthesis; later burning phases beyond core He burning and shell C burning have a significant effect on post-explosive production factors. We also discuss the implications of the uncertainties in the helium burning rates for evidence of a new primary neutron capture process (LEPP) in massive stars. Subject headings: nuclear reactions, nucleosynthesis, abundances, Supernovae:General
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