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.
@article{arxiv.1208.6006,
title = {Model-independent measurement of the top quark polarisation},
author = {J. A. Aguilar-Saavedra and R. V. Herrero-Hahn},
journal= {arXiv preprint arXiv:1208.6006},
year = {2015}
}
Comments
LaTeX 12 pages. Discussion expanded with a new plot, references added. Final version to appear in PLB