collisions the wavefunction of the incoming hadron is, except for a very small part, in the soft physics region. If the $S$-matrix is near zero for central collisions then the inelastic reaction will feed into elastic scattering as a shadow. In deep inelastic scattering at small-x when $S$ becomes black there will certainly be a similar phenomenon which occurs, and which has been described in Sec.3.1, but, in addition, blackness in the small $k_\perp$ region will allow higher values of $k_\perp$ to become effective thus making the process semihard.

If central impact parameter collisions of $\gamma^*$-proton collisions are indeed black for $k_\perp \approx \mu$ then we would expect the x-dependence of the single diffractive cross section, $x_P{d\sigma\over d x_P},$ to vary more strongly with  x than suggested by the soft pomeron. If one writes

$$x_P{d\sigma\over dx_P} \propto x^{-n}\eqno(3.8)$$

then both ZEUS\[6\] and H1\[7\] now suggest that $n \approx 0.4$ rather than the $n=2(\alpha_P-1) \approx 0.2$ predicted by the soft pomeron. If the ZEUS and H1 measurements hold up, and  n really is near 0.4 in the small $\beta$ region, then I think it becomes clear that semihard physics is dominating the physics of large mass diffraction dissociation. In that case 