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arXiv · hep-ex/0109011

Search for Lepton Flavour Violation in e+e- Collisions at sqrt(s) = 189 - 209 GeV

The OPAL collaboration·G. Abbiendi
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Abstract

We search for lepton flavour violating events (e mu, e tau and mu tau) 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 sqrt(s). A single e mu 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 sigma(e+e- -> e mu, e tau and mu tau) as a function of sqrt(s) at LEP2 energies.

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The OPAL collaboration, G. Abbiendi. 2001-09-10. Search for Lepton Flavour Violation in e+e- Collisions at sqrt(s) = 189 - 209 GeV. https://doi.org/10.1016/s0370-2693(01)01086-3

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