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Realistic Calculation of the hep Astrophysical Factor

L. E. Marcucci·R. Schiavilla·M. Viviani·A. Kievsky·S. Rosati
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Abstract

The astrophysical factor for the proton weak capture on 3He is calculated with correlated-hyperspherical-harmonics bound and continuum wave functions corresponding to a realistic Hamiltonian consisting of the Argonne v18 two-nucleon and Urbana-IX three-nucleon interactions. The nuclear weak charge and current operators have vector and axial-vector components, that include one- and many-body terms. All possible multipole transitions connecting any of the p-3He S- and P-wave channels to the 4He bound state are considered. The S-factor at a p-3He center-of-mass energy of 10 keV, close to the Gamow-peak energy, is predicted to be 10.1 10^{-20} keV b, a factor of five larger than the standard-solar-model value. The P-wave transitions are found to be important, contributing about 40 % of the calculated S-factor.

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L. E. Marcucci, R. Schiavilla, M. Viviani, A. Kievsky, S. Rosati. 2000-03-29. Realistic Calculation of the hep Astrophysical Factor. https://doi.org/10.1103/physrevlett.84.5959

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