Direct capture astrophysical S factors at low energy

Abstract

We investigate the energy dependence of the astrophysical S factors for the reactions 7Be(p,gamma)8B, the primary source of high-energy solar neutrinos in the solar pp chain, and 16O(p,gamma)17F, an important reaction in the CNO cycle. Both of these reactions have predicted S factors which rise at low energies; we find the source of this behavior to be a pole in the S factor at a center-of-mass energy E = -E_B, the point where the energy of the emitted photon vanishes. The pole arises from a divergence of the radial integrals.

8 pages including 2 figures

Cited by in corpus (11)

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• Uncertainties in extracting $S_{17}$ from transfers
• Low Energy Behavior of the \protect(^{7}\protect) Be \protect( (p,γ)^{8}\protect) B reaction
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• Nuclear astrophysics from direct reactions