Gauge-invariant meson photoproduction with extended nucleons

Abstract

The general gauge-invariant photoproduction formalism given by Haberzettl is applied to kaon photoproduction off the nucleon at the tree level, with form factors describing composite nucleons. Numerical results show that this gauge-invariance procedure, when compared to Ohta's, leads to a much improved description of experimental data. Predictions for the new Bonn SAPHIR data for $p(\gamma ,K^{+})\Lambda$ are given.

Comments: 4 pages; Contribution to the Proceedings of Baryons '98, Bonn, September 22-26, 1998