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arXiv · 1306.6187

Two-neutrino double-beta decay Fermi transition and two-nucleon interaction

Dusan Stefanik·Fedor Simkovic·Kazuo Muto·Amand Faessler
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Abstract

An exactly solvable model for a description of the two-neutrino double beta decay transition of the Fermi type is considered. By using perturbation theory an explicit dependence of the two-neutrino double beta decay matrix element on the like-nucleon pairing, particle-particle and particle-hole proton-neutron interactions by assuming a weak violation of isospin symmetry of Hamiltonian expressed with generators of the SO(5) group. It is found that there is a dominance of double beta decay transition through a single state of the intermediate nucleus. Then, an energy weighted sum rule connecting Delta Z=2 nuclei is presented and discussed. It is suggested that this sum rule can be exploited to study the residual interactions of the nuclear Hamiltonian.

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Dusan Stefanik, Fedor Simkovic, Kazuo Muto, Amand Faessler. 2013-06-26. Two-neutrino double-beta decay Fermi transition and two-nucleon interaction. https://doi.org/10.1103/physrevc.88.025503

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