Photo- and electroproduction of nonstrange baryon resonances in the relativized quark model

Photoproduction amplitudes for the nonstrange baryons are calculated in a quark model with an electromagnetic transition operator containing relativistic corrections, and relativized-quark-model wave functions. A one-parameter fit to the photocouplings shows significant improvements over models using the nonrelativistic transition operator or nonrelativistic wave functions. Helicity asymmetries and other ratios in the electroproduction of some low-lying resonances are also predicted.