Bounds on the Number of Light Neutrinos Species, <i>g'</i>₁ Coupling and <i>Z - Z′</i> Mixing Angle in a U(1)_B-L Model

Abstract

The constraints on the number of neutrinos generations, g' 1 coupling and Z - Z′ mixing angle through the invisible width method, and in the framework of a U(1) B-L model are obtained. Based on the experimental value reported by the LEP for the rate , we obtained a bound on the g' 1 coupling, . In addition, we derive 90% C.L. bounds on the Z - Z′ mixing angle , improving the existing bounds by one order of magnitude.