K-0-SIGMA(+) PHOTOPRODUCTION WITH SAPHIR

Preliminary results of the analysis of the reaction gamma + p --> K-0 + Sigma(+) are presented. We show the first measurement of the differe ntial cross section and data for the total cross section, which are mu ch improved with respect to previous measurements. The data are compar ed with model predictions from different isobar and quark models that give a good description of gamma + p --> K+ + Lambda and gamma + p --> K+ + Sigma(0) data in the same energy range. Results of ChPT describe the data adequately et threshold, while isobar models that include ha dronic form factors reproduce the data at intermediate energies.