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Relativistic Two-Body Processes in Axial-Charge Transitions

E. D. Izquierdo·G. Barenboim·A. O. Gattone
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Abstract

We study the contribution of two-body meson-exchange processes to axial charge transitions for nuclei in the lead, tin and oxygen regions. We conduct calculations in the Dirac-Hartree (the Walecka model) and the relativistic Hartree (where the full one-nucleon-loop effects are included) approximations. We present results indicating that one- and two-body processes enhance the matrix elements of the axial-charge operator by some (100+-20)% in all three regions studied. This agrees well with the fit of eighteen first-forbidden beta-decay transitions conducted by Warburton in the lead region. We also discuss some sensitivities present in the calculation.

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E. D. Izquierdo, G. Barenboim, A. O. Gattone. 1995-04-07. Relativistic Two-Body Processes in Axial-Charge Transitions. https://doi.org/10.1016/s0375-9474(96)00276-x

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