On the Energy Dependence of DIS in the Diffraction Region of Low X

Abstract

The energy dependence of the virtual photoabsorption cross section in deep inelastic scattering (DIS) at low $x = Q^2/W^2 < 0.1$ may be described in terms of the saturation scale that in our approach depends on the energy, $Λ^2_{sat} = Λ^2_{sat} (W^2)$. We briefly summarize our recent findings that allow us to predict the exponent $C_2$ of $Λ^2_{sat} (W^2) \sim (W^2)^{C_2}$ in agreement with the previous result obtained from fitting the experimental data. The exponent $C_2$ depending on the relative magnitude of the longitudinal and transverse contribution to the structure function, direct measurements of the longitudinal part are urgently needed.

To appear in the proceedings of the XIth International Conference on Elastic and Diffractive Scattering Chateau de Blois, France, May 15-20, 2005