Geometric Scaling for the Totalγ*pCross Section in the LowxRegion

We observe that the saturation model of deep inelastic scattering predicts a geometric scaling of the total ${\gamma }^{*}p$ cross section in the region of small Bjorken variable $x$. The geometric scaling in this case means that the cross section is a function of only one dimensionless variable $\tau {=Q}^2{R}_0^2\left(x\right)$, where the function $R_0\left(x\right)$ decreases with decreasing $x$. We show that the experimental data from HERA in the region $x<\mathrm{}0.01\mathrm{}$ confirm the expectations of this scaling over a very broad region of $Q^2$. We suggest that the geometric scaling is more general than the saturation model.