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W pair production cross-section and W branching fractions in e+e- interactions at 189 GeV

The DELPHI Collaboration·P. Abreu
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Abstract

The cross-section for the process e+e- -> W+W- has been measured with the data sample collected by DELPHI at an average centre-of-mass energy of 189 GeV and corresponding to an integrated luminosity of 155 pb^{-1}. Based on the 2392 events selected as WW candidates, the cross-section for the doubly resonant process e+e- -> W+W- has been measured to be 15.83 +- 0.38 (stat) +- 0.20 (syst) pb. The branching fractions of the W decay were also measured and found to be in good agreement with the Standard Model expectation. From these a value of the CKM mixing matrix element |V_{cs}| = 1.001 +- 0.040 (stat) +- 0.020 (syst) was derived.

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The DELPHI Collaboration, P. Abreu. 2001-03-12. W pair production cross-section and W branching fractions in e+e- interactions at 189 GeV. https://doi.org/10.1016/s0370-2693(00)00314-2

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