Chargino Production and Decay in Photon-Photon-Collisions

Abstract

We discuss the pair production of charginos in collisions of polarized photons $γγ\to \tildeχ_i^+ \tildeχ_i^-$, ($i=1,2$) and the subsequent leptonic decay of the lighter chargino $\tildeχ_1^+ \to \tildeχ_1^0 e^+ ν_e$ including the complete spin correlations. Analytical formulae are given for the polarization and the spin-spin correlations of the charginos. Since the production is a pure QED process the decay dynamics can be studied separately. For high energy photons from Compton backscattering of polarized laser pulses off polarized electron beams numerical results are presented for the cross section, the angular distribution and the forward-backward asymmetry of the decay positron. Finally we study the dependence on the gaugino mass parameter $M_1$ and on the sneutrino mass for a gaugino-like MSSM scenario.