Dependence of S-Process Nucleosynthesis in Massive Stars on Triple-Alpha and 12C(a,g)16O Reaction Rate Uncertainties

Abstract

We have studied the sensitivity of s-process nucleosynthesis in massive stars to +/- 2 sigma variations in the rates of the triple alpha and 12C(a,g)16O 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 58Fe and 96Zr change strongly with changes in the He burning reaction rates; using the Lodders (2003) solar abundances rather than those of Anders and Grevesse (1989) reduces s-process nucleosynthesis; later burning phases beyond core He burning and the 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.

Submitted to the Astrophysical Journal

References in corpus (4)

• Nucleosynthesis and Remnants in Massive Stars of Solar Metallicity
• Nucleosynthesis in the Early Galaxy
• s-Process Nucleosynthesis in Advanced Burning Phases of Massive Stars
• On the Sensitivity of Massive Star Nucleosynthesis and Evolution to Solar Abundances and to Uncertainties in Helium Burning Reaction Rates

Cited by in corpus (13)

• The 12C(a,g)16O reaction and its implications for stellar helium burning
• Pair decay width of the Hoyle state and carbon production in stars
• Galactic Chemical Evolution: the Impact of the 13C-pocket Structure on the s-process Distribution
• Neutron capture cross section of unstable 63Ni: implications for stellar nucleosynthesis
• Code dependencies of pre-supernova evolution and nucleosynthesis in massive stars: Evolution to the end of core helium burning
• 11B and Constraints on Neutrino Oscillations and Spectra from Neutrino Nucleosynthesis
• $\theta$-dependence of light nuclei and nucleosynthesis
• Realistic 3D hydrodynamics simulations find significant turbulent entrainment in massive stars
• The s-Process Enrichment of the Globular Clusters M4 and M22
• A chemical signature from fast-rotating low-metallicity massive stars: ROA 276 in omega Centauri
• Signature of a massive rotating metal-poor star imprinted in the Phoenix stellar stream
• Impacts of the ${}^{12}\mathrm{C}{\left(\alpha ,\gamma \right)}^{16}\mathrm{O}$ reaction rate on ${}^{56}\mathrm{Ni}$ nucleosynthesis in pair-instability supernovae
• The impact of new ($\alpha$, n) reaction rates on the weak s-process in metal-poor massive stars