Atomic parity violation in cesium and implications for the 3-3-1 models

Abstract

The parity violation in cesium atom is analysed in the framework of the models based on the SU(3) C ×SU(3) L ×U(1) N gauge group. It is shown that in the minimal version, the main contribution to a deviation of weak charge ΔQ W due to direct Z′ exchange is negative. New data on parity violation in the cesium atom seems not favour to the minimal version, while it gets a positive value in the version with right-handed neutrinos. We obtain a bound on the Z′ mass at a range from 1.4 TeV to 2.6 TeV. The allowed regions for the Z– Z′ mixing angle are also derived.