Theory of the electromagnetic structure functions of the proton

The knowledge of the wave function of a relativistic composite system constitutes a complete description of its intrinsic properties such as mass spectrum, elastic and inelastic form factors, and structure functions. The wave functions of the proton obtained from the O(4,2) infinite-multiplet model, which were used previously to calculate mass spectra and form factors, are applied to reevaluate in a more complete manner the structure functions in closed form. The resultant scaling functions obey the Drell-Yan relation $F_2\left(\xi \right)\sim {(1-\xi )}^3$ and, under certain conditions, the Callan-Cross relation $F_2\left(\xi \right)\approx 2\xi F_1\left(\xi \right)$.