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CP sensitive observables in e+e- -> neutralino_i neutralino_j and neutralino decay into the Z boson

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

We study CP sensitive observables in neutralino production e+e- -> neutralino_i neutralino_j and the subsequent two-body decays of the neutralino neutralino_i -> neutralino_n Z and of the Z boson Z -> l \bar l (q \bar q). We identify the CP odd elements of the Z boson density matrix and propose CP sensitive triple-product asymmetries. We calculate these observables and the cross sections in the Minimal Supersymmetric Standard Model with complex parameters μand M_1 for an e+e- linear collider with \sqrt{s}=800 GeV and longitudinally polarized beams. We show that the asymmetries can reach 3% for Z -> l \bar l and 18% for Z -> q \bar q and discuss the feasibility of measuring these asymmetries.

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A. Bartl, H. Fraas, O. Kittel, W. Majerotto. 2004-06-25. CP sensitive observables in e+e- -> neutralino_i neutralino_j and neutralino decay into the Z boson. https://doi.org/10.1140/epjc%2Fs2004-01893-2

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