Chargino production and decay in photon–photon collisions

Abstract

We discuss the pair production of charginos in collisions of polarized photons γγ →χ + νe 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 M1 and on the sneutrino mass for a gaugino-like MSSM scenario.

Physics at the e+ e- Linear Collider

“…A linear collider running in γγ mode (two backscattered laser beams) has been considered in [1179,1180] for chargino pair production and in [1181] for sfermion production. For γγ collisions, the couplings are pure QED so that the production cross sections depend only on the mass of the charged sparticles which are being produced.…”

Physics at the $$e^+ e^-$$ e + e - linear collider

“…A linear collider running in mode (two back-scattered laser beams) has been considered in [ 1315 , 1316 ] for chargino pair production and in [ 1317 ] for sfermion production. For collisions, the couplings are pure QED so that the production cross sections depend only on the mass of the charged sparticles which are being produced.…”

New Results for a Photon-Photon Collider

“…3 However, chargino pair production at a photon collider can still be used to measure the chargino mass. In addition, the parameter independence of the production cross section allows one to study the chargino decay dynamics in a theoretically clean way and offers sensitivity, e.g., to M 1 and the sneutrino mass through the branching ratio and forward-backward asymmetry in the decay χ+ 1 → χ0 1 e + ν e [19]. Beyond the tree level, radiative corrections due to quark and squark loops can modify the cross section in γγ collisions by up to 3% [20].…”