Muon decay process in the framework of the leptons with four-component neutrino and the restriction on neutrino mass

Considered is muon decay in the framework of the leptons scheme with four-component neutrino, in which only one lepton charge is introduced and μ+, ν, e- are leptons. The electron (positron) energy spectrum taking into account the possible neutrino mass is calculated and the formula for the rho Michel parameter is found. The rho parameter as a neutrino mass function are determined by the least square method. The existing experimental data are analyzed relative to the rho parameter and the permissible values of neutrino mass are found. Among the experimental restrictions the strongest is msub(ν) < or equal to 0.21 MeV resulting from rho=0.7523+-0.0024