  Nuclear shadowing and color glass condensate are possible only at
sufficiently small x where parton clouds of different nucleons overlap in the
longitudinal direction. Another condition vital for these effect, an overlap of
partons in impact parameters, is not easy to fulfill for gluons which are
located within small spots, as follows from the observed weakness of
diffractive gluon radiation (smallness of the triple-Pomeron coupling). The
predicted weakness of the leading twist gluon shadowing has been confirmed
recently by data for J/Psi production and Cronin effect in d-Au collisions at
RHIC. Smallness of gluonic spots also leads to a rather low value of the slope
of the Pomeron trajectory, confirmed by ZEUS data on elastic photoproduction of
J/Psi. At the same time, saturation of unitarity for central pp collisions
leads to a substantial increase of the Pomeron slope in good agreement with
elastic pp data.

High Energy Physics - Phenomenology