Search for structure in $pi$$sup -$p $Yields$ $lambda$K$sup 0$ at $Sigma$K threshold

We have measured the cross section, the angular distribution, and the A polarization for the reaction pi p yields DELTA K/sup 0/. A spark-chamber spectrometer was used to collect 8400 DELTA K/sup )/ events at fourteen beam momenta near SIGMA K threshold. Our data do not show the prominent cross- section enhancement suggested by some previous experiments. However, detailed structure in the cross section and the angular distribution agrees well with a simple model which includes a cusp effect at SIGMA K threshold. (auth)