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arXiv · 1203.0989

Calculation of nuclear matrix elements in neutrinoless double electron capture

Tomas R. Rodriguez·Gabriel Martinez-Pinedo
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Abstract

We compute nuclear matrix elements for neutrinoless double electron capture on $^{152}$Gd, $^{164}$Er and $^{180}$W nuclei. Recent precise mass measurements for these nuclei have shown a large resonance enhancement factor that makes them the most promising candidates for observing this decay mode. We use an advanced energy density functional method which includes beyond mean-field effects such as symmetry restoration and shape mixing. Our calculations reproduce experimental charge radii and $B(E2)$ values predicting a large deformation for all these nuclei. This fact reduces significantly the values of the NMEs leading to half-lives larger than $10^{29}$ years for the three candidates.

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Tomas R. Rodriguez, Gabriel Martinez-Pinedo. 2012-03-05. Calculation of nuclear matrix elements in neutrinoless double electron capture. https://doi.org/10.1103/physrevc.85.044310

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