Q2dependence of nuclear shadowing

We reexamine the predictions of a two-phase model of shadowing in nuclear deep-inelastic scattering in light of new NMC data on the x, A, and ${\mathit{Q}}^2$ dependence of the ratios of structure functions. The model, which combines vector meson dominance at low ${\mathit{Q}}^2$ with diffractive Pomeron exchange for large ${\mathit{Q}}^2$, agrees with the observed small, but nonzero, slopes in log${\mathit{Q}}^2$, which indicate the importance of higher twist shadowing effects in the transition region, 0.1≲${\mathit{Q}}^2$≲1 ${\mathrm{GeV}}^2$. We note also that the latest E665 data on the deuteron to proton ratio suggests the presence of a small amount of shadowing in the deuteron.