Neutral-strange-particle production in 200-Gev/cpπ+K+

Abstract

We have used the Fermilab 30-in. bubble-chamber-hybrid spectrometer to study neutral-strangeparticle production in the interactions of 200-GeV/c protons and a+ and K + mesons with nuclei of gold, silver, and magnesium. Average multiplicities and inclusive cross sections for KO and A 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 KO and A production, and also the same for proton and at beams. Average KO and A multiplicities, as well as their ratio, have been measured as functions of the numbers of projectile collisions v, and secondary collisions v, in the nucleus, and indicate that rescattering contributes significantly to enhancement of A production but not to KO production. The properties of events with multiple KO' s or A's also corroborate this conclusion. KO rapidities are in the central region and decrease gently with increasing v,, while A rapidities are in the targetfragmentation region and are independent of v,. KO and A multiplicities increase with the rapidity loss of the projectile, but their rapidities do not.PACS number(s): 13.85. Ni, 25.40.Ve,

Strangeness production in nuclear interactions at 200 A GeV and the number of nucleon-nucleon collisions

“…It should be noted here that data of three experiments [9,10,11] are not consistent. This can be seen by comparing kaons in pAg from [11] with kaons in pXe in [10], kaons in pAr in [10] and kaons in pS [9]. Quoted number of kaons in the same experiment has also changed with increased statistics by more then 30% [8,9].…”

“…These assumptions require a few comments. Data [10,11] on Λ production in pA interactions has been parametrized [10,11] as…”

“…Ratios of mean numbers of Λ and K 0 s per event over negative hadrons h − , denoted as < Λ > / < h − > and < K 0 s > / < h − > has been measured by NA-35 Collaboration [8,9] and found to be about twice as large as the same ratios in pA collisions [8,9,10,11]. Compilations of data can be found in Refs.…”

Overview, goals, and preliminary results of E910 laboratory directed research and development at Lawrence Livermore National Laboratory

“…AyvVt -rapidity loss of incident proton [11,12,13] collisions suffered by incident proton (slow proton distribution) [8,9,10] total collisions with target nucleons (net charge) [5,6,7] Studies of this kind have been performed before, but with very low statistics data sets by present standards.…”