Extraction of Electrostrong Parameters of $N^{*}(1520)$ from Eta Photoproduction

Abstract

Recently obtained polarized target and photon asymmetry data in eta photoproduction are shown to be very powerful, in conjunction with the differential cross-section data, in yielding model-insensitive constraints on the electrostrong parameters for the excitation and decay of the $N^{*}(1520)$ resonance. The extracted ratio of its electromagnetic helicity amplitudes, $A_{3/2}/A_{1/2}$, provides a critical test for the QCD-inspired hadron models.