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arXiv · hep-ph/0312168

An anomalous Wtb coupling at a linear collider

K. Kolodziej
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Abstract

Differential cross sections of secondary particles in a process of top quark pair production and decay into six fermions at a linear collider with an unpolarized and a longitudinally polarized electron beam are computed to the lowest order in the standard model and in the presence of an anomalous Wtb coupling. It is illustrated that the latter has a little impact on the differential cross sections. In particular, it is shown that the angular distribution of a secondary lepton receives practically no contribution from the anomalous Wtb coupling, even if the top quark is produced off shell and the non-double resonance background contributions are taken into account. This finding is in accordance with the decoupling theorem that has been proven in literature in the narrow top quark width approximation.

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K. Kolodziej. 2003-12-12. An anomalous Wtb coupling at a linear collider. https://doi.org/10.1016/j.physletb.2004.01.017

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