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arXiv · hep-ph/9506354

New vector-scalar contributions to neutrinoless double beta decay and constraints on R-parity violation

K. S. Babu·R. N. Mohapatra
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Abstract

We show that in minimal supersymmetric standard model (MSSM) with R-parity breaking as well as in the left-right symmetric model, there are new observable contributions to neutrinoless double beta decay arising from hitherto overlooked diagrams involving the exchange of one W boson and one scalar boson. In particular, in the case of MSSM, the present experimental bounds on neutrinoless double beta decay lifetime improves the limits on certain R-parity violating couplings by about two orders of magnitude. It is shown that similar diagrams also lead to enhanced rates for $μ^-\rightarrow e^+$ conversion in nuclei, which are in the range accessible to ongoing experiments.

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K. S. Babu, R. N. Mohapatra. 1995-06-18. New vector-scalar contributions to neutrinoless double beta decay and constraints on R-parity violation. https://doi.org/10.1103/physrevlett.75.2276

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