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SMMC method for two-neutrino double beta decay

P. B. Radha·D. J. Dean·S. E. Koonin·T. T. S. Kuo·K. Langanke·A. Poves·J. Retamosa·P. Vogel
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Abstract

Shell Model Monte Carlo (SMMC) techniques are used to calculate two-neutrino double beta decay matrix elements. We validate the approach against direct diagonalization for $^{48}$Ca in the complete $pf$-shell using the KB3 interaction. The method is then applied to the decay of $^{76}$Ge in the $(0f_{5/2},1p,0g_{9/2})$ model space using a newly calculated realistic interaction. Our result for the matrix element is $0.13\pm0.05$ MeV$^{-1}$, in agreement with the experimental value.

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P. B. Radha, D. J. Dean, S. E. Koonin, T. T. S. Kuo, K. Langanke, A. Poves, J. Retamosa, P. Vogel. 1995-10-25. SMMC method for two-neutrino double beta decay. https://doi.org/10.1103/physrevlett.76.2642

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