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Approximate symmetries in nuclei and the $2νββ$-decay rate

O. A. Rumyantsev·M. H. Urin
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Abstract

A nonstandard method for calculating the nuclear $2νββ$ - decay amplitude is proposed. The method is based on the explicit use of those approximate symmetries of a nuclear hamiltonian, which correspond to the operators of allowed $β$ -- transitions. Within the framework of the proposed method the mentioned amplitude is calculated for a wide range of nuclei. The model parameters used in calculations are taken from independent data. Calculated \bb half-lifes are compared with known experimental data.

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O. A. Rumyantsev, M. H. Urin. 1996-08-22. Approximate symmetries in nuclei and the $2νββ$-decay rate. https://arxiv.org/abs/nucl-th/9608051

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