Limits on the Electromagnetic and Weak Dipole Moments of the Tau-Lepton in E_6 Superstring Models

Abstract

We obtain limits on the electromagnetic and weak dipole moments of the tau-lepton in the framework of a Left-Right symmetric model (LRSM) and a class of $E_6$ inspired models with an additional neutral vector boson $Z_{\theta }$. Using as an input the data obtained by the L3 and OPAL Collaborations for the reaction $e^{+}{e}^{-}\to {\tau }^{+}{\tau }^{-}\gamma$, we get a stringent limit on the LRSM mixing angle $\varphi$, $-1.66\times 10^{-3}<\varphi <1.22\times 10^{-3}$, which in turn induces bounds on the tau weak dipole moments which are consistent with the bounds obtained recently by the DELPHI and ALEPH Collaborations from the reaction $e^{+}{e}^{-}\to {\tau }^{+}{\tau }^{-}$. We also get similar bounds for the weak dipole moments of the tau lepton in the framework of $E_6$ superstring models.

18 pages, 5 figures

Cited by in corpus (2)

• Constraints on Left-Right Symmetric and $E_6$ Superstring Models from the Number of Light Neutrino Species
• The effects of lepton KK modes on the lepton electric dipole moments in the Randall Sundrum scenario