Neutral-strange-particle Production In 200-gev/c P/pi+/k+ Interactions On Au, Ag, and Mg

We have used the Fermilab 30-in. bubble-chamber-hybrid spectrometer to study neutral-strange-particle production in the interactions of 200-GeV/c protons and pi+ and K+ mesons with nuclei of gold, silver, and magnesium. Average multiplicities and inclusive cross sections for K0 and LAMBDA are measured, and a power law is found to give a good description of their A dependence. The exponent characterizing the A dependence is consistent with being the same for K0 and LAMBDA-production, and also the same for proton and pi+ beams. Average K0 and LAMBDA-multiplicities, as well as their ratio, have been measured as functions of the numbers of projectile collisions-nu(p) and secondary collisions-nu(s), in the nucleus, and indicate that rescattering contributes significantly to enhancement of LAMBDA-production but not to K0 production. The properties of events with multiple K0's or LAMBDA's also corroborate this conclusion. K0 rapidities are in the central region and decrease gently with increasing nu(p), while LAMBDA-rapidities are in the target-fragmentation region and are independent of nu(p). K0 and LAMBDA-multiplicities increase with the rapidity loss of the projectile, but their rapidities do not.