Transverse-momentum distribution of secondaries from high-energy nuclear interactions and interpretation by means of a statistical model

Abstract

An analysis of the experimental transverse momentumpt of secondary particles produced in high-energy nuclear interactions in the accelerator energy region is carried out. The average value ofpt for each kind of particle is almost constant for primary energy from 6 GeV up to cosmic-ray energy. Several theoreticalpt distributions are fitted to the experimentalpt distribution. The experimentalpt distributions of π-mesons, K-mesons, nucleons, Λ and Σ were well fitted by the theo-reticalpt distributions derived from the momentum distributions of Planck for mesons and of Fermi for baryons. The characteristic parameterkT involved in the theoreticalpt distribution is nearly constant for all kinds of particles and is ∼0.125 GeV. It is shown that thept distribution of protons from large-angle p-p elastic scattering and that of secondaries from inelastic interactions are similar in shape and are governed by the same statistical law. The relations between the above twopt distributions are discussed. On the basis of statistical theory, a derivation of the theoreticalPt distribution is given.