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تسجيل مستخدم جديدMeasuring SUSY Parameters at LEP II Using Chargino Production and Decay
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Previously, in the context of the minimal supersymmetric standard model (without {em a priori} assumptions of parameter unification), we studied the constraints on weak-scale SUSY parameters from chargino production at LEP II, using as observables $mch$, $mLSP$, the cross section and the leptonic branching fraction. Here, exploiting the high degree of polarization in chargino production, we add to our earlier work the forward-backward asymmetries of the visible hadrons and leptons in chargino decays. For a chargino that is mostly gaugino, the parameter space can now be restricted to a small region; $tanb$ is constrained, the soft electroweak gaugino and electron sneutrino masses are determined to about 10%, and the sign of $mu$ may be determined. Constraints for a chargino that is mostly Higgsino are much weaker, but still disfavor the hypothesis that the chargino is mostly gaugino. For a chargino which is a roughly equal mixture of Higgsino and gaugino, we find intermediate results.
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