Inelastic Electron-Proton Scattering and Vector-Meson Dominance

A simple phenomenological picture of scaling is proposed based on generalized vector-meson dominance. This picture may provide a possible mechanism of scaling in the context of an analytic-$S$-matrix approach such as the dual-resonance model. The present model suggests that a very weak spectral function in the large-photon-mass region is sufficient to give the magnitude and shape of scaling-limit functions. Thus the measurement of $\nu W_2$ explains why $\rho$-meson dominance works in high-energy photoreactions. Experimental implications of the model, in particular the expected missing-mass distribution, are also discussed.