A model for deep inelastic structure functions

Abstract

We calculate the electromagnetic structure functions from an infinite component wave equation which is a relativistic generalization of the Schrödinger equation of the H atom. The elastic form factor has a dipole structure leading to the threshold behavior of F 2 ( ξ) α(1− ξ 3 at ξ = 1. Apart from that, F 2 ( ξ) differs from the structure function of the proton by being larger and by having a zero at ξ = 0. While our amplitude appears at first sight to be typical resonance model for the structure functions, all properties of the result allow for a direct interpretation in terms of the parton picture. A specific choice of the mass parameters reduces our model to that of the H atom. In this limiting case we show that the result is almost identical to what one would obtain from the parton approximation.