Kinetic mixing effect in the 3-3-1-1 model

TL;DR

This paper investigates how kinetic mixing between gauge bosons in the 3-3-1-1 model affects electroweak parameters and fermion interactions, providing constraints from flavor-changing neutral currents.

Contribution

It identifies the kinetic mixing as a new source of gauge boson mixing in the 3-3-1-1 model and analyzes its impact on physical observables.

Findings

Kinetic mixing modifies the ta-parameter and Z-fermion couplings.

Constraints from flavor-changing neutral currents are derived.

Gauge boson mixings influence fermion interactions.

Abstract

We show that the mixing effect of the neutral gauge bosons in the 3-3-1-1 model comes from two sources. The first one is due to the 3-3-1-1 gauge symmetry breaking as usual, whereas the second one results from the kinetic mixing between the gauge bosons of U(1)_X and U(1)_N groups, which are used to determine the electric charge and baryon minus lepton numbers, respectively. Such mixings modify the \rho-parameter and the known couplings of Z with fermions. The constraints that arise from flavor-changing neutral currents due to the gauge boson mixings and non-universal fermion generations are also given.