Electromagnetic Couplings of Nucleon Resonances

Abstract

An effective Lagrangian calculation of pion photoproduction including all nucleon resonances up to $\sqrt{s}=1.7$ GeV is presented. We compare our results to recent calculations and show the influence of different width parametrizations and offshell cutoffs on the photoproduction multipoles. We determine the electromagnetic couplings of the resonances from a new fit to the multipole data.

Comments: 20 pages, latex, 6 figures. Misprints corrected, text & 3 figures added