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arXiv · nucl-th/9802028

Direct capture astrophysical S factors at low energy

B. K. Jennings·S. Karataglidis·T. D. Shoppa
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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.

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B. K. Jennings, S. Karataglidis, T. D. Shoppa. 1998-04-14. Direct capture astrophysical S factors at low energy. https://doi.org/10.1103/physrevc.58.579

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