Journal article
Search for lepton flavour violation in e( )e(-) collisions at root s=189-209 GeV
G Abbiendi, C Ainsley, PF Akesson, G Alexander, J Allison, G Anagnostou, KJ Anderson, S Arcelli, S Asai, D Axen, G Azuelos, I Bailey, E Barberio, RJ Barlow, RJ Batley, T Behnke, KW Bell, PJ Bell, G Bella, A Bellerive Show all
PHYSICS LETTERS B | ELSEVIER | Published : 2001
Abstract
We search for lepton flavour violating events (eμ, eτ and μτ) that could be directly produced in e+e- annihilations, using the full available data sample collected with the OPAL detector at centre-of-mass energies between 189 GeV and 209 GeV. In general, the Standard Model expectations describe the data well for all the channels and at each √s. A single eμ event is observed where according to our Monte Carlo simulations only 0.019 events are expected from Standard Model processes. We obtain the first limits on the cross-sections σ (e+e- → eμ, eτ and μτ) as a function of √s at LEP2 energies. © 2001 Elsevier Science B.V. All rights reserved.