Would unitarity slow down the rise of $F_2(x,Q^2)$ at $x\to 0$?

Abstract

On the grounds of the $U$--matrix form of $s$--channel unitarization, we consider constraints unitarity provides for the total cross--section of the virtual photon--induced reactions and discuss the preasymptotic nature of hadron and photon scatterings at $\sqrt{s}\le 0.5$ TeV.

Comments: 8 pages, LaTeX, no figures