Quasianapole Interaction of Charged Fermions

We obtain the analytic expression for the total cross section of the reaction $e^-e^+\to l^-l^+$ ($l=\mu,\tau$) taking possible quasianapole interaction effects into account. We find numerical restrictions on the interaction parameter value from data for the reaction $e^-e^+\to\mu^-\mu^+$ in the energy domain below the $Z^0$ peak.