The scaling in \sigma \gamma *p (W2, Q2) cross sections (for Q2/W2 \ll 1) in terms of the scaling variable \eta = (Q2 + m20)/ \Lambda 2 (W2) is interpreted in the Generalized Vector Dominance/Color-Dipole Picture (GVD/CDP). The quantity \Lambda 2 (W2) is identified as the average gluon transverse momentum absorbed by the q \bar q state, (\vec l\bot 2\rangle = (1/6) \Lambda 2 (W2 ). At any Q2, for W2 \to \infty , the cross sections for virtual and real photons become universal, \sigma \gamma *p (W2,Q2)/ \sigma \gamma p (W2) \to 1. The gluon density corresponding to the color-dipole cross section in the appropriate limit is found to be consistent with the results from QCD fits.
PACS numbers: 12.38.--t, 12.40.--y, 13.60.--r
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