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Measurement of the Angular Distribution of Electrons from W to e nu Decays Observed in ppbar Collisions at sqrt(s) = 1.8 TeV

D0 Collaboration·B. Abbott
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Abstract

We present a preliminary measurement of the electron angular distribution parameter alpha2 in W to e nu events using data collected by the D0 detector during the 1994--1995 Tevatron run. We compare our results with next-to-leading order perturbative QCD, which predicts an angular distribution of 1 +/- alpha1 cos theta* +alpha_2 cos^2 theta*, where theta* is the angle between the charged lepton and the antiproton in the Collins-Soper frame. In the presence of QCD corrections, the parameters alpha1 and alpha2 become functions of pT(W), the W boson transverse momentum. We present the first measurement of alpha_2 as a function of pT(W). This measurement is of importance, because it provides a test of next-to-leading order QCD corrections which are a non-negligible contribution to the W mass measurement.

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D0 Collaboration, B. Abbott. 1999-07-15. Measurement of the Angular Distribution of Electrons from W to e nu Decays Observed in ppbar Collisions at sqrt(s) = 1.8 TeV. https://arxiv.org/abs/hep-ex/9907022

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