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A T-odd asymmetry in neutralino production and decay

A. Bartl·H. Fraas·S. Hesselbach·K. Hohenwarter-Sodek·G. Moortgat-Pick
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Abstract

We study CP-violating effects in neutralino production and subsequent decay within the Minimal Supersymmetric Standard Model with complex parameters M_1 and mu. The observable we propose is a T-odd asymmetry based on a triple product in neutralino production e^+ e^- -> tilde{chi}^0_i tilde{chi}^0_2, i = 1,...,4, with subsequent leptonic three-body decay tilde{chi}^0_2 -> tilde{chi}^0_1 l^+ l^-, l = e, mu, at an e^+ e^- linear collider with sqrt{s} = 500 GeV and polarised beams. We provide compact analytical formulae for the cross section and the T-odd asymmetry taking into account the complete spin correlations between production and decay. We give numerical predictions for the cross section and the T-odd asymmetry. The asymmetry can go up to 10 %.

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A. Bartl, H. Fraas, S. Hesselbach, K. Hohenwarter-Sodek, G. Moortgat-Pick. 2004-11-03. A T-odd asymmetry in neutralino production and decay. https://doi.org/10.1088/1126-6708%2F2004%2F08%2F038

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