Study of scalar top quarks in the neutralino and chargino decay channel

The scalar top discovery potential has been studied with a full-statistics background simulation at s=500 GeV and L=500 fb−1 for the TESLA project. The beam polarization is very important to measure the scalar top mixing angle and to determine its mass. The latest estimation of the beam polarization parameters is applied. This study includes e+ polarization, which improves the sensitivity. For a 180 GeV scalar top at minimum production cross section, we obtain Δm=0.8 GeV and Δ cos θt=0.008 in the neutralino decay channel, and Δm=0.5 GeV and Δ cos θt=0.004 in the chargino decay channel.