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Measurement of gauge boson couplings and W spin density matrix

Evelyne Delmeire
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Abstract

During the LEP2 period the e+e- collider increased its center of mass energy from 161 GeV to 209 GeV and a total integrated luminosity of approximately 700 pb-1 was recorded per experiment. Pairs of W bosons are produced and allow the study of gauge boson couplings involving W, Z and photon. The coupling of the W boson to the neutral gauge bosons have been measured and are in agreement with the Standard Model prediction. Limits are set on CP-violating couplings by a Spin Density Matrix analysis of the W decay products. No evidence has been found for couplings of three neutral gauge bosons. Limits are derived on couplings of four gauge bosons.

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Evelyne Delmeire. 2003-05-13. Measurement of gauge boson couplings and W spin density matrix. https://arxiv.org/abs/hep-ex/0305025

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