DEPENDENCE OF s-PROCESS NUCLEOSYNTHESIS IN MASSIVE STARS ON TRIPLE-ALPHA AND {sup 12}C({alpha}, {gamma}){sup 16}O REACTION RATE UNCERTAINTIES

Journal Article · Thu Sep 10 04:00:00 EDT 2009 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/702/2/1068; COUNTRY OF INPUT: INTERNATIONAL ATOMIC ENERGY AGENCY (IAEA)· OSTI ID:21336046

Tur, Clarisse; Austin, Sam M ^[1]; Heger, Alexander ^[2]

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1. National Superconducting Cyclotron Laboratory, Michigan State University, 1 Cyclotron Laboratory, East Lansing, MI 48824-1321 (United States)
2. School of Physics and Astronomy, University of Minnesota, Twin Cities, Minneapolis, MN 55455-0149 (United States)

We have studied the sensitivity of s-process nucleosynthesis in massive stars to {+-}2{sigma} variations in the rates of the triple-{alpha} and {sup 12}C({alpha}, {gamma}){sup 16}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 {sup 58}Fe and {sup 96}Zr change strongly with changes in the He burning reaction rates; using the Lodders solar abundances rather than those of Anders and Grevesse 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.

• OSTI ID: 21336046
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 702; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
ABUNDANCE
ALPHA REACTIONS
CARBON 12 TARGET
GAMMA RADIATION
HELIUM BURNING
IRON 58
NEUTRON REACTIONS
NUCLEOSYNTHESIS
OXYGEN 16
REACTION KINETICS
S PROCESS
SIMULATION
SUPERNOVAE
ZIRCONIUM 96