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Two-neutrino double beta decay within Fully-Renormalized QRPA: Effect of the restoration of the Ikeda sum rule

L. Pacearescu·V. Rodin·F. Simkovic·Amand Faessler
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Abstract

The recently proposed Fully-Renormalized QRPA (FR-QRPA), which fullfils the Ikeda sum rule (ISR) exactly, is applied to the two-neutrino double beta decay of $^{76}$Ge, $^{82}$Se, $^{100}$Mo, $^{116}$Cd, $^{128}$Te and $^{130}$Xe. The results obtained are compared with those of other approaches, standard QRPA and self-consistent QRPA (SCQRPA). The similarities and the differences among the methods are discussed. The influence of the restoration of the Ikeda sum rule on the $2νββ$-decay amplitude is analyzed.

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L. Pacearescu, V. Rodin, F. Simkovic, Amand Faessler. 2003-08-12. Two-neutrino double beta decay within Fully-Renormalized QRPA: Effect of the restoration of the Ikeda sum rule. https://doi.org/10.1103/physrevc.68.064310%2010.1103%2Fphysrevc.75.059902

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