On radiative decay of $Z^{\prime }$ boson

Abstract

In the framework of the extended $SU(2{)}_h\times SU(2{)}_l$ model we study the radiative decay of an extra gauge boson $Z^{\prime }$, $Z^{\prime }\to \gamma Z$. The data analysis results of the CDF collaboration at the Fermilab Tevatron allow one to establish not only the lower bound of the decay probability $Z^{\prime }\to \gamma Z$ normalized to Drell-Yan process $Z^{\prime }\to {\mu }^{+}{\mu }^{-}$, $R(Z^{\prime }\to \gamma Z/{\mu }^{+}{\mu }^{-})>1.4\times 10^{-5}{\cot }^2\varphi$, but also to estimate the mixing angle $\xi$ between the states $Z^{\prime }$ and $Z$, $|\xi |<5\times 10^{-2}$, taking into account the additional mixing angle $\varphi$ related to the extended gauge group $SU(2{)}_h\times SU(2{)}_l$. The comparison with the decays $Z^{\prime }\to {\tau }^{+}{\tau }^{-}$ and $Z^{\prime }\to \bar{b}b$, $Z^{\prime }\to \bar{t}t$ based on the LEP data is also presented.

Comments: 13 pages, 2 figures