Multiplicity distribution and mechanisms of the high-energy hadron collisions

We discuss the multiplicity distribution for the highest accessible energies of {ital pp} and {bar p}p interactions from the point of view of multiparton collisions. The inelastic cross sections for single {sigma}{sub 1} and multiple (double and, presumably, triple) {sigma}{sub 2} parton collisions are calculated from the analysis of experimental data on the multiplicity distribution up to Fermilab Tevatron energies. It is found that {sigma}{sub 1} becomes energy independent while {sigma}{sub 2} increases with {radical} (s) for {radical} (s) {ge}200 GeV. The observed growth of {l_angle}p{sub {perpendicular}}{r_angle} with multiplicity is attributed to the increasing role of multiparton collisions for the high-energy {bar p}p(pp)-inelastic interactions. {sigma}{sub 2+3} reproduces quite well the cross section for minijet production. {copyright} {ital 1999} {ital The American Physical Society}