ep - e x / 99 07 02 2 v 1 1 5 Ju l 1 99 9 Measurement of the Angular Distribution of Electrons from W →
نویسندگان
چکیده
We present a preliminary measurement of the electron angular distribution parameter α2 in W → eν events using data collected by the DØ detector during the 1994–1995 Tevatron run. We compare our results with next-toleading order perturbative QCD, which predicts an angular distribution of (1±α1 cosθ∗+α2 cosθ), where θ∗ is the angle between the charged lepton and the antiproton in the Collins-Soper frame. In the presence of QCD corrections, the parameters α1 and α2 become functions of p W T , the W boson transverse momentum. We present the first measurement of α2 as a function of p W T . 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. ∗Submitted to the International Europhysics Conference on High Energy Physics, EPS-HEP99, 15 – 21 July, 1999, Tampere, Finland.
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