ρ-A2 Exchange Degeneracy and the Adler Sum Rule

On the basis of ρ-A₂ exchange degeneracy, the structure functions for virtual Compton scattering with I=1 and C=+/-1 in the t channel are assumed proportional to one another. The constant of proportionality is determined by the threshold relation of Bloom and Gilman. The Adler sum rule (I=1, C=-1) is found to be consistent with the observed behavior of the structure function (I=1, C=+1) in the scaling region. A simple proportionality relation between ν(W^ν¯p₂-W^νp₂) and ν(W^γp₂-W^γn₂) is obtained in the scaling limit.