Search for excited taus from Z0 decays

Abstract We have searched for excited taus from Z 0 decay in the channels e + e − → τ ∗+ τ ∗− → τ + τ − γ γ and e + e − → ττ ∗ → τ + τ − γ , using the L3 detector at LEP. Using the τ ∗ pair production channel, we can exclude a τ ∗ up to a mass of 45.5 geV at 95% confidence level. We have also determined upper limits on the ττ ∗ Z 0 and ττ ∗ γ couplings as a function of m τ∗ up to 89.3 GeV.