Previously, in the context of the minimal supersymmetric standard model (without a priori assumptions of parameter unification), we studied the constraints on weak-scale SUSY parameters from chargino production at CERN LEP II, using as observables $m_{{\tilde{\chi }}_1^{\pm }}{,m}_{{\tilde{\chi }}_1^0}$, 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; tanβ is constrained, the soft electroweak gaugino and electron sneutrino masses are determined to about 10%, and the sign of μ 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.

• Received 31 July 1996

DOI:https://doi.org/10.1103/PhysRevD.55.1326