CP violation in selectron cascade decays e_L -> e X_2^0 -> e X_1^0 mu+ mu-

J. A. Aguilar-Saavedra

doi:10.1016/j.physletb.2004.06.088

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CP violation in selectron cascade decays e_L -> e X_2^0 -> e X_1^0 mu+ mu-

J. A. Aguilar-Saavedra

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Abstract

Selectron decays constitute a source of 100% polarised neutralinos, whose helicity is fixed by the charge and "chirality" of the decaying selectron. In SUSY scenarios where the second neutralino X_2^0 has three-body decays, the cascade decay e_L -> e X_2^0 -> e X_1^0 mu+ mu- provides a clean place to study CP violation in the neutralino sector, through the analysis of CP-violating asymmetries involving the X_2^0 spin s and the momenta of the muons. We show that a CP-violating asymmetry in the triple product s . (p_mu- x p_mu+) could be observable at a 800 GeV linear collider provided the gaugino mass M_1 has a large phase at the electroweak scale. We compare our results with X_1^0 X_2^0 production, where a CP asymmetry is also observable within these scenarios.

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J. A. Aguilar-Saavedra. 2004-06-28. CP violation in selectron cascade decays e_L -> e X_2^0 -> e X_1^0 mu+ mu-. https://doi.org/10.1016/j.physletb.2004.06.088

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