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arXiv · 0811.0344

Measurement of W-Boson Helicity Fractions in Top-Quark Decays Using costheta*

T. Aaltonen
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Abstract

Fully reconstructed top-antitop-events are used to determine the fractions of right-handed and longitudinally polarized W bosons produced in top-quark decays. The helicity fractions are sensitive to the couplings and the Dirac structure of the Wtb vertex. This paper reports measurements of the W-boson helicity fractions from two different methods using data corresponding to an integrated luminosity of 1.9 fb-1 of proton-antiproton collisions collected by the CDF II detector operating at the Fermilab Tevatron.

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T. Aaltonen. 2009-04-06. Measurement of W-Boson Helicity Fractions in Top-Quark Decays Using costheta*. https://doi.org/10.1016/j.physletb.2009.02.040

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