Hadronic properties of the S11(1535) resonance studied by electroproduction off the deuteron

We propose a new method for studying properties of excited states of hadrons based on electroproduction of baryon resonances from the deuteron. The measurement is capable of distinguishing between competing models of a specific resonance by exploiting the sensitivity of the cross section to the radius and compositeness of the resonances. These studies are made feasible, in part, by the strong hadronic reinteraction of the resonance with the spectator neutron in specific kinematic situations. We establish our claims by studying the reaction d[e,e'S11(1535)]N for Q2≥1 GeV2, where the S11 suffers a prominent final state interaction. Sensitivity to the model is established by comparing numerical results obtained from a constituent quark model and an effective chiral Lagrangian model of the S11. copyright 1999 The American Physical Society