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Shell Model Study of the Double Beta Decays of $^{76}$Ge, $^{82}$Se and $^{136}$Xe

E. Caurier·F. Nowacki·A. Poves·J. Retamosa
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Abstract

The lifetimes for the double beta decays of $^{76}$Ge, $^{82}$Se and $^{136}$Xe are calculated using very large shell model spaces. The two neutrino matrix elements obtained are in good agreement with the present experimental data. For $ <1$ eV we predict the following upper bounds to the half-lives for the neutrinoless mode: $T^{(0ν)}_{1/2}(Ge) > 1.85\,10^{25} yr.$, $T^{(0ν)}_{1/2}(Se) > 2.36\,10^{24} yr.$ and $T^{(0ν)}_{1/2}(Xe) > 1.21\,10^{25} yr$. These results are the first from a new generation of Shell Model calculations reaching O(10$^{8}$) dimensions.

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E. Caurier, F. Nowacki, A. Poves, J. Retamosa. 1996-01-12. Shell Model Study of the Double Beta Decays of $^{76}$Ge, $^{82}$Se and $^{136}$Xe. https://doi.org/10.1103/physrevlett.77.1954

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