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arXiv · hep-ex/0107046

Angular Analysis of the Muon Pair Asymmetry at LEP 1

The OPAL collaboration·G. Abbiendi
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Abstract

Data on muon pair production obtained by the OPAL collaboration at centre of mass energies near the Z peak are analysed. Small angular mismatches between the directions of the two muons are used to assess the effects of initial state photon radiation and initial-final-state radiation interference on the forward-backward asymmetry of muon pairs. The dependence of the asymmetry on the invariant mass of the pair is measured in a model-independent way. Effective vector and axial-vector couplings of the Z boson are determined and compared to the Standard Model expectations.

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The OPAL collaboration, G. Abbiendi. 2001-07-19. Angular Analysis of the Muon Pair Asymmetry at LEP 1. https://doi.org/10.1016/s0370-2693(01)00896-6

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