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arXiv · 1404.1585

New directions for top quark polarization in the $t$-channel process

J. A. Aguilar-Saavedra·S. Amor dos Santos
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Abstract

We define three orthogonal axes to investigate the top quark polarization in the $t$-channel single top process. We provide expressions for the polarization in these axes in terms of anomalous $Wtb$ couplings. It is found that the polarizations in the two axes orthogonal to the spectator quark axis are very sensitive to an anomalous coupling involving a $\bar b_L σ^{μν} t_R$ dipole term. In particular, an asymmetry based on the polarization normal to the production plane is more sensitive to the imaginary part of this coupling than previously studied observables.

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J. A. Aguilar-Saavedra, S. Amor dos Santos. 2014-06-20. New directions for top quark polarization in the $t$-channel process. https://doi.org/10.1103/physrevd.89.114009

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