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arXiv · 1208.6006

Model-independent measurement of the top quark polarisation

J. A. Aguilar-Saavedra·R. V. Herrero-Hahn
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Abstract

We introduce a new asymmetry in the decay t -> W b -> l nu b, which is shown to be directly proportional to the polarisation of the top quark along a chosen axis, times a sum of W helicity fractions. The latter have already been precisely measured at the Tevatron and the Large Hadron Collider. Therefore, this new asymmetry can be used to obtain a model-independent measurement of the polarisation of top quarks produced in any process at hadron or lepton colliders.

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J. A. Aguilar-Saavedra, R. V. Herrero-Hahn. 2012-11-20. Model-independent measurement of the top quark polarisation. https://doi.org/10.1016/j.physletb.2012.11.031

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