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arXiv · hep-ph/9812463

Neutrinoless double beta decay in Supersymmetry with bilinear R-parity breaking

M. Hirsch·J. W. F. Valle
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Abstract

We reanalyze the contributions to neutrinoless double beta ($\znbb$) decay from supersymmetry with explicit breaking of R-parity. Although we keep both bilinear and trilinear terms, our emphasis is put on bilinear R-parity breaking terms, because these mimic more closely the models where the breaking of R-parity is spontaneous. Comparing the relevant Feynman diagrams we conclude that the usual mass mechanism of double beta decay is the dominant one. From the non-observation of $\znbb$ decay we set limits on the bilinear R-parity breaking parameters of typically a (few) 100 $keV$. Despite such stringent bounds, we stress that the magnitude of R-parity violating phenomena that can be expected at accelerator experiments can be very large, since they involve mainly the third generation, while $\znbb$ decay constrains only the first generation couplings.

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M. Hirsch, J. W. F. Valle. 1999-06-08. Neutrinoless double beta decay in Supersymmetry with bilinear R-parity breaking. https://doi.org/10.1016/s0550-3213(99)00368-5

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