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CP asymmetries in neutralino production

A. Bartl·H. Fraas·O. Kittel·W. Majerotto
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Abstract

We study two CP sensitive triple-product asymmetries for neutralino production e+e- \to \tildeχ^0_i \tildeχ^0_j and the subsequent leptonic two-body decays \tildeχ^0_i \to \tilde{l} l of one of the neutralinos and of the slepton \tilde{l} \to \tildeχ^0_1 l at an e+e--linear collider with \sqrt{s} = 500 GeV. We calculate the asymmetries in the Minimal Supersymmetric Standard Model with complex parameters μand M_1. We show that the largest asymmetries are 10% or 25% and estimate the event rates which are necessary to measure the asymmetries. Polarized electron and positron beams can significantly enhance the asymmetries and cross sections. In addition, we show how the two decay leptons can be distinguished by making use of their energy distributions.

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A. Bartl, H. Fraas, O. Kittel, W. Majerotto. 2003-08-13. CP asymmetries in neutralino production. https://arxiv.org/abs/hep-ph/0308143

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