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arXiv · 1607.04258

Revision of the LHCb Limit on Majorana Neutrinos

Brian Shuve·Michael E. Peskin
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Abstract

We revisit the recent limits from LHCb on a Majorana neutrino N in the mass range 250 - 5000 MeV. These limits are among the best currently available, and they will be improved soon by the addition of data from Run 2 of the LHC. LHCb presented a model-independent constraint on the rate of like-sign leptonic decays, and then derived a constraint on the mixing angle V{\mu}4 based on a theoretical model for the B decay width to N and the N lifetime. The model used is unfortunately unsound. We revise the conclusions of the paper based on a decay model similar to the one used for the tau lepton and provide formulae useful for future analyses.

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Brian Shuve, Michael E. Peskin. 2016-07-14. Revision of the LHCb Limit on Majorana Neutrinos. https://doi.org/10.1103/physrevd.94.113007

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