Abstract
In order to describe diffractive excitation of hadrons, a vector-vector form for the imaginary amplitude is proposed. The vector transition operator is related to the ordinary vector current. This description gives approximate s-channel helicity conservation in elastic πN scattering and a differential cross section for elastic NN scattering proportional to the fourth power of the magnetic form factor of the nucleon. All inelastic cross sections for excitation of hadron resonances should dip in the very near forward direction. Calculating the matrix elements of the diffractive transition operator in a relativistic quark model with essentially no free parameters, we get quantitative results which are not in obvious disagreement with experiment for most nucleon and pion resonances.