Constraints on leptophobic Z′ models from electroweak experiments -: art. no. 115008

We study the constraints from updated electroweak data on the three leptophobic Z' models, the eta model with an appropriate U(1)'-U(1)(Y) kinetic mixing, a Z' model motivated by the flipped SU(5) X U(1) unification, and the phenomenological Z' model of Agashe. Graesser, and Hinchliffe. The Z-Z' mixing effects are parametrized in terms of a positive contribution to the T parameter, T-new, and the effective mass mixing parameter, <(xi)over bar>. All the theoretical predictions for the T boson parameters, the W boson mass and the observables in low-energy neutral current experiments are presented together with the standard model radiative corrections. The allowed region in the (<(xi)over bar>,T-new) plane is shown for the three models. The 95% C.L. lower limit on the heavier mass eigenstate Z(2) is given as a function of the effective Z-Z' mixing parameter zeta. [S0556-2821(98)09921-4].