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arXiv · 1211.4523

Measurement of W-Boson Polarization in Top-quark Decay using the Full CDF Run II Data Set

CDF Collaboration
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Abstract

We measure the polarization of W bosons from top-quark (t) decays into final states with a charged lepton and jets, tt --> WbWb --> lvbqqb, using the full Run II data set collected by the CDF II detector. A model-independent method simultaneously determines the fraction of longitudinal (f_0) and right-handed (f_+) W bosons to yield f_0 = 0.726 +/- 0.066 (stat) +/- 0.067 (syst) and f_+ = -0.045 +/- 0.044 (stat) +/- 0.058 (syst) with a correlation coefficient of -0.69. Additional results are presented under various standard model assumptions. No significant discrepencies with the standard model are observed.

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CDF Collaboration. 2013-01-29. Measurement of W-Boson Polarization in Top-quark Decay using the Full CDF Run II Data Set. https://doi.org/10.1103/physrevd.87.031104

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