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arXiv · hep-ex/9709027

Search for Unstable Heavy and Excited Leptons in e^+e^- Collisions at sqrt{s} = 170-172 GeV

The OPAL Collaboration·K. Ackerstaff et al
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Abstract

We have searched for unstable neutral and charged heavy leptons, N and L^+/-, and for excited states of neutral and charged leptons, nu*, e*, mu* and tau*, in e^+e^- collisions at centre-of-mass energies of 170 and 172 GeV using the OPAL detector at LEP. No evidence for their existence was found. From the analysis of charged-current decays of pair-produced unstable heavy leptons, and of charged-current and photonic decays of pair-produced excited leptons, lower limits on their masses are derived. From the analysis of charged-current and photonic decays of singly-produced excited leptons, upper limits on the ratio of the coupling to the compositeness scale, f/Lambda, are determined for masses up to the kinematic limit.

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The OPAL Collaboration, K. Ackerstaff et al. 1997-09-23. Search for Unstable Heavy and Excited Leptons in e^+e^- Collisions at sqrt{s} = 170-172 GeV. https://doi.org/10.1007/s100520050061

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