Strange Particle Production

Abstract

A great of papers is devoted to the investigation of the processes of the strange particle production. However, a major part of the results obtained is insufficiently accurate and may be considered as a rough preliminary estimate only. Further we shall consider in detail the part of the experimental information which concerns the cross sections for the strange particle production. At present the cross sections for the hyperon production in pion-nucleon collisions a t an energy T < 1,5 BeVl) and the relative probabilities of the K-meson pair production by the antinucleon annihilation are known most precisley. In other cases still few direct measurements of the cross sections have been made, and the conclusions about the magnitude of these cross sections can be drawn only on the basis of indirect data. I n what follows we shall use the following abbreviated notations for the methods by which the experimental data have been obtained:H-BC and P-BC the hydrogen and propan bubble chambers respectively ; H-DC and D-DC the hydrogen and deuterium diffusion chambers; C counters ; Em H-Em particles produced in irradiating the hydrogen target are N I n cases when in determining the cross sections one has essentially used theoretical assumptions, these will be given in the corresponding remarks. We shall aduce the same errors as indicated in the experimental papers. If the cross sections are determined from indirect data, the given errors can characterize only the accuracy of the experimental data used. The true errors of the cross sections in these cases are noticeably larger than the indicated ones but of the same order of magnitude. When the errors due to the recalculation are essentially larger than the experimental ones, one will indicate only the order of the cross section magnitude.the interaction of primary particles in the photoemulsion ; detected in the photoemulsion. method of measurement is not indicated. Two particle ReactionsTo check the derivations of theoretical models describing the strange particle production one uses the cross sections for two-particle reactions with strange I) Here and in the following T is the kinetic energy of particles in lab. system.