Impact parameter dependence of parton densities at low x

We consider impact parameter dependence of the polarized and unpolarized parton densities. Unitarity does not allow factorization of these structure functions over the Bjorken x and the impact parameter b variables. On the basis of the particular geometrical model approach we conclude that spin of constituent quark may have a significant orbital angular momentum component which can manifest itself through the peripherality of the spin dependent structure functions.Comment: 4 pages, to appear in the Proceedings of the Workshop Diffraction 2000, Cetraro, Italy, 2-7 September 200

On the extreme behaviour of g1(x,Q2)g_1(x,Q^2) at x→0x\to 0

On the basis of the U-matrix form of s-channel unitarization, we consider constraints unitarity provides for the spin structure function $g_1(x,Q^2)$ at $x\to 0$. Corresponding constraint for the spin structure function $h_1(x, Q^2)$ is given along.Comment: 4 pages, latex, enlarged, to be published in Phys. Lett.

Energy dependence of gap survival probability and antishadowing

We discuss energy dependence of gap survival probability which follows from rational form of amplitude unitarization. In contrast to eikonal form of unitarization which leads to decreasing energy dependence of gap survival probability, we predict a non-monotonous form for this dependence.Comment: 9 pages, 3 figures, revised and extended versio

Indication on the universal hadron substructure - constituent quarks

The universality of single-spin asymmetry on inclusive pi-meson production is discussed. This universality can be related to the hadron substructure - constituent quarks.Comment: 3 pages, 3 figures, references adde