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Weak Magnetism in Two Neutrino Double Beta Decay

C. Barbero·F. Krmpotić·A. Mariano·D. Tadić
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Abstract

We have extended the formalism for the two-neutrino double beta decay by including the weak-magnetism term, as well as other second-forbidden corrections. The weak magnetism diminishes the calculated half-lives in $\sim 10%$, independently of the nuclear structure. Numerical computations were performed within the pn-QRPA, for $^{76}Ge$, $^{82}Se$, $^{100} Mo$, $^{128}Te$ and $^{130}Te$ nuclei. No one of the second-forbidden corrections modifies significantly the spectrum shapes. The total reduction in the calculated half lives varies from 6% up to 32%, and strongly depend on the nuclear interaction in the particle-particle $S=1,T=0$ channel. We conclude that the higher order effects in the weak Hamiltonian would hardly be observed in the two-neutrino double beta experiments.

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C. Barbero, F. Krmpotić, A. Mariano, D. Tadić. 1998-10-27. Weak Magnetism in Two Neutrino Double Beta Decay. https://doi.org/10.1016/s0370-2693(98)01391-4

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