Absorptive corrections to the reaction γp→nπ in the one pion exchange model with gauge invariant extension

Absorptive corrections have been calculated for photoproduction ofN ^*. Two versions for the uncorrected production amplitude are used. First, the one pion exchange Born approximation in the Coulomb gauge and second, a gauge invariant extension, restricted to the orbital electromagnetic current and to the isospinI=1-amplitude in thet-channel. We found the second restriction to be unimportant. Numerical values for cross sections and decay correlations in the BeV region are given in diagram form. Present day experimental accuracy does not allow to test the effects of absorption.