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arXiv · 0709.2431

$ΔL=2$ hyperon semileptonic decays

C. Barbero·Ling-Fong Li·G. Lopez Castro·A. Mariano
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Abstract

We compute the rates of semileptonic B_A \to B_Bl^-l^- (l=e or μ) hyperon transitions in a model where intermediate states involve loops of baryons and a Majorana neutrino. These rates turn out to be well below present experimental bounds and other theoretical estimates. From the experimental upper limit on the Ξ^- \to pμ^-μ^- decay, we derive the bound < 22 TeV for the effective Majorana mass of the muon neutrino. Also, an estimate of background contributions for these decays due to the allowed B_A \to B_Bl^-l^-\barν\barν decays are provided.

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C. Barbero, Ling-Fong Li, G. Lopez Castro, A. Mariano. 2007-09-17. $ΔL=2$ hyperon semileptonic decays. https://doi.org/10.1103/physrevd.76.116008

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