The x-region of shadowing corrections in nucleon structure functions

We discuss the experimental indications on the behaviour of F2(x, Q2) at small x both in proton and nuclear targets. By comparing the parametrizations of the data we conclude that shadowing correction effects in a proton target can appear at a noticeable level for x = (2–4) × 10−4 and Q2 ∼ 101GeV2, namely inside the HERA regime.