REALISTIC MODELS WITH A LIGHT U(1) GAUGE BOSON COUPLED TO BARYON NUMBER

We recently showed that a new gauge boson γB coupling only to baryon number is phenomenologically allowed, even if mB<mZ and αB0.2. In our previous work we assumed that kinetic mixing between the baryon number and hypercharge gauge bosons (via an FBμνFμνY term) was small enough to evade constraints from precision electroweak measurements. In this paper we propose a class of models in which this term is naturally absent above the electroweak scale. We show that the generation of a mixing term through radiative corrections in the low-energy effective theory does not lead to a conflict with precision electroweak measurements and may provide a leptonic signal for models of this type at an upgraded Fermilab Tevatron. © 1995 The American Physical Society.