Dipole moments of the tau-neutrino from the process e+e−→νν¯γ

Abstract

In the framework of a Simplest Little Higgs Model (SLHM), we calculate the total cross section for the reaction $e^{+}{e}^{-}\to \nu \overline{\nu }\gamma$ and thereafter we get a limit on the characteristic energy scale of the model f, $f\ge 5.5TeV$, which in turn induces bounds on the anomalous Magnetic Moment (MM) and the Electric Dipole Moment (EDM) of the tau-neutrino. We consider initial-state radiation, and neglect W and photon exchange diagrams. The results are based on the data reported by the L3 Collaboration at LEP, and compare favorably with the limits obtained in other models, complementing previous studies on the dipole moments.