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arXiv · 1509.05157

Neutrinoless double positron decay and positron emitting electron capture in the interacting boson model

J. Barea·J. Kotila·F. Iachello
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Abstract

Neutrinoless double-$\beta$ decay is of fundamental importance for determining the neutrino mass. Although double electron ($\beta^-\beta^-$) decay is the most promising mode, in very recent years interest in double positron ($\beta^+\beta^+$) decay, positron emitting electron capture ($EC\beta^+$), and double electron capture ($ECEC$) has been renewed. We present here results of a calculation of nuclear matrix elements for neutrinoless double-$\beta^+$ decay and positron emitting electron capture within the framework of the microscopic interacting boson model (IBM-2) for $^{58}$Ni, $^{64}$Zn, $^{78}$Kr, $^{96}$Ru, $^{106}$Cd, $^{124}$Xe, $^{130}$Ba, and $^{136}$Ce decay. By combining these with a calculation of phase space factors we calculate expected half-lives.

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J. Barea, J. Kotila, F. Iachello. 2015-09-17. Neutrinoless double positron decay and positron emitting electron capture in the interacting boson model. https://doi.org/10.1103/physrevc.87.057301

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