Diffraction off nuclei in color singlet models of shadowing

The assumption that only color singlet interactions between projectiles and nucleons in nuclei are relevant for the nuclear shadowing and the AGK cutting rules are used to estimate the cross section of diffraction and the multiplicity fluctuations for eA scattering at HERA energies. We find that for sufficiently light nuclei, A ≤ 20, the result only weakly depends on the details of the model, and that a large fraction of events is expected to be of diffractive nature. At the same time, a significant fraction of non-diffractive events should have multiplicities much larger than those observed in ep scattering.