Rapidity density distributions in antiproton-proton collisions

Abstract Data on the density of charged particles in rapidity space for annihilation and non-annihilation pp interactions at 7.3 and 12 GeV/ c are reported. It is shown that the central rapidity density for non-annihilation processes is a simple linear function of ln ( s ) from these low energies up to pp collider energies ( s =540 GeV ). Significant differences in density distributions for pp and e − e + annihilations at comparable energies are found.