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arXiv · 1001.4714

Normal tau polarisation as a sensitive probe of CP violation in chargino decay

Herbi K. Dreiner·Olaf Kittel·Anja Marold
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Abstract

CP violation in the spin-spin correlations in chargino production and subsequent two-body decay into a tau and a tau-sneutrino is studied at the ILC. From the normal polarisation of the tau, an asymmetry is defined to test the CP-violating phase of the higgsino mass parameter μ. Asymmetries of more than \pm70% are obtained, also in scenarios with heavy first and second generation sfermions. Bounds on the statistical significances of the CP asymmetries are estimated. As a result, the normal tau polarisation in the chargino decay is one of the most sensitive probes to constrain or measure the phase ϕ_μat the ILC, motivating further detailed experimental studies.

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Herbi K. Dreiner, Olaf Kittel, Anja Marold. 2010-01-26. Normal tau polarisation as a sensitive probe of CP violation in chargino decay. https://doi.org/10.1103/physrevd.82.116005

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