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CP-violating asymmetry in chargino decay into neutralino and W boson

H. Eberl·T. Gajdosik·W. Majerotto·B. Schrausser
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Abstract

In the MSSM with complex parameters, loop corrections to $\cha_i^\pm \to \neu_j^0 W^\pm$ lead to a CP violating asymmetry $\ACP = (Γ(\cha_i^+ \to \neu_j^0 W^+) - Γ(\cha_i^- \to \neu_j^0 W^-))/ (Γ(\cha_i^+ \to \neu_j^0 W^+) + Γ(\cha_i^- \to \neu_j^0 W^-))$. We calculate this asymmetry at full one-loop level. We perform a detailed numerical analysis for $\cha_1^\pm \to \neu_1^0 W^\pm$ and $\cha_2^\pm \to \neu_1^0 W^\pm$ analyzing the dependence on the parameters and phases involved. Asymmetries of several percent are obtained. We also discuss the feasability of measuring these asymmtries at LHC.

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H. Eberl, T. Gajdosik, W. Majerotto, B. Schrausser. 2005-06-03. CP-violating asymmetry in chargino decay into neutralino and W boson. https://doi.org/10.1016/j.physletb.2005.05.033

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