Diffractive dissociation from non-linear evolution in DIS on nuclei

The process of single diffractive dissociation off nuclei is considered on a basis of solutions to the nonlinear evolution equation. The relevant saturation scales $Q_{s A}^D(x,x_0)$ are determined and their dependences on Bjorken $x$, atomic number $A$, and minimal rapidity gap $Y_0\equiv \ln 1/x_0$ are investigated. The solutions are shown to posses the geometrical scaling in a broad kinematic region for $x$ well below $x_0$. A detailed theoretical discussion of saturation scale and scaling is presented. The ratio $\sigma^{diff}/\sigma^{tot}$ is computed for several nuclei. We predict that at $x\simeq 10^{-4}$ this ratio is of the order 25% which is much larger to the one of proton. This result indicates a possibility to observe a very strong nuclear shadowing.