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Weak capture of protons by protons

R. Schiavilla·V. G. J. Stoks·W. Gloeckle·H. Kamada·A. Nogga·J. Carlson·R. Machleidt·V. R. Pandharipande·R. B. Wiringa·A. Kievsky·S. Rosati·M. Viviani
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Abstract

The cross section for the proton weak capture reaction $^1H(p,e^+ν_e)^2H$ is calculated with wave functions obtained from a number of modern, realistic high-precision interactions. To minimize the uncertainty in the axial two-body current operator, its matrix element has been adjusted to reproduce the measured Gamow-Teller matrix element of tritium $β$ decay in model calculations using trinucleon wave functions from these interactions. A thorough analysis of the ambiguities that this procedure introduces in evaluating the two-body current contribution to the pp capture is given. Its inherent model dependence is in fact found to be very weak. The overlap integral $Λ^2(E=0)$ for the pp capture is predicted to be in the range 7.05--7.06, including the axial two-body current contribution, for all interactions considered.

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R. Schiavilla, V. G. J. Stoks, W. Gloeckle, H. Kamada, A. Nogga, J. Carlson, R. Machleidt, V. R. Pandharipande, R. B. Wiringa, A. Kievsky, S. Rosati, M. Viviani. 1998-08-06. Weak capture of protons by protons. https://doi.org/10.1103/physrevc.58.1263

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