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Search for right-handed W bosons in top quark decay

D0 Collaboration·V. Abazov
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Abstract

We present a measurement of the fraction f+ of right-handed W bosons produced in top quark decays, based on a candidate sample of $t\bar{t}$ events in the lepton+jets decay mode. These data correspond to an integrated luminosity of 230pb^-1, collected by the DO detector at the Fermilab Tevatron $p\bar{p}$ Collider at sqrt(s)=1.96 TeV. We use a constrained fit to reconstruct the kinematics of the $t\bar{t}$ and decay products, which allows for the measurement of the leptonic decay angle $θ^*$ for each event. By comparing the $\cosθ^*$ distribution from the data with those for the expected background and signal for various values of f+, we find f+=0.00+-0.13(stat)+-0.07(syst). This measurement is consistent with the standard model prediction of f+=3.6x10^-4.

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D0 Collaboration, V. Abazov. 2005-08-17. Search for right-handed W bosons in top quark decay. https://doi.org/10.1103/physrevd.72.011104

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