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arXiv · hep-ph/9911298

Bounds on effective Majorana neutrino masses at HERA

Marion Flanz·Werner Rodejohann·Kai Zuber
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Abstract

The lepton-number violating process e p \to nu_e l l' X mediated by Majorana neutrinos is studied for the HERA collider for (l l') = (e tau), (mu tau), (mu mu) and (tau tau). Only the muonic decay of the tau is considered. The direct limit on the effective muon Majorana mass, is improved significantly to 4.0 times 10^3 GeV and for the first time direct limits on the analogous effective masses connected with the tau sector are given, namely 4.2 times 10^3 GeV for , 4.4 times 10^3 GeV for and 2.0 times 10^4 GeV for . We find that a more general analysis for an upgraded HERA could improve this values by a factor of up to 40, yet still being orders of magnitude worse than indirect limits.

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Marion Flanz, Werner Rodejohann, Kai Zuber. 2000-03-07. Bounds on effective Majorana neutrino masses at HERA. https://doi.org/10.1016/s0370-2693(99)01483-5

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