Trimuon production in \nu N-scattering as a probe of massive neutrinos

Abstract

The lepton-number violating process \nu_\mu N \to \mu^- \mu^+ \mu^+ X is studied for the first time in connection with Majorana neutrino masses of the second generation. The sensitivity for light and heavy Majorana neutrinos is investigated. The ratio with respect to the standard model charged current process is improved by some orders of magnitude if compared to previously discussed Majorana induced \Delta L_{\mu} = 2 processes. Non-observation of this process in previous experiments allows to demand the effective mass to be < m_{\mu \mu} > \ls 10^4 GeV, being more stringent than previously discussed direct bounds, however still unnaturally high. Therefore, in the forseeable future, indirect bounds on effective masses other than m_{ee} will be more stringent.