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arXiv · hep-ex/0301027

Measurement of W Polarisation at LEP

L3 Collaboration
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Abstract

The three different helicity states of W bosons produced in the reaction e+ e- -> W+ W- -> l nu q q~ at LEP are studied using leptonic and hadronic W decays. Data at centre-of-mass energies \sqrt s = 183-209 GeV are used to measure the polarisation of W bosons, and its dependence on the W boson production angle. The fraction of longitudinally polarised W bosons is measured to be 0.218 \pm 0.027 \pm 0.016 where the first uncertainty is statistical and the second systematic, in agreement with the Standard Model expectation.

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L3 Collaboration. 2003-01-16. Measurement of W Polarisation at LEP. https://doi.org/10.1016/s0370-2693(03)00172-2

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