Inclusive study of strange-particle production inppinteractions at 405 GeV/c

Abstract

We have studied inclusive $K_S^0$, $\Lambda$, and $\overline{\Lambda }$ production and strange-resonance production in the reactions $\mathrm{pp}\to (K_S^0, \Lambda , or \overline{\Lambda })+{\pi }^{\pm }+\mathrm{anything}$ at 405 GeV/c. The observed cross sections are 7.43 ± 0.45 mb for $K_S^0$, 4.01 ± 0.35 mb for $\Lambda$, and 0.63 ± 0.12 mb for $\overline{\Lambda }$. From the analyses of the effective-mass distributions for the ($K_S^0{\pi }^{\pm }$), ($\Lambda {\pi }^{\pm }$), and ($\overline{\Lambda }{\pi }^{\pm }$) systems, the resonance production cross sections are determined as 4.1 ± 1.0 mb for $K^{*+}\mathrm{}\left(890\right)\mathrm{}$, 3.6 ± 1.0 mb for $K^{*-}\mathrm{}\left(890\right)\mathrm{}$, 3.4 ± 1.7 mb for $K^{*\pm }\mathrm{}\left(1420\right)\mathrm{}$, 0.67 ± 0.12 mb for ${\Sigma }^{+}\mathrm{}\left(1385\right)\mathrm{}$, 0.45 ± 0.09 mb for ${\Sigma }^{-}\mathrm{}\left(1385\right)\mathrm{}$, and 0.25 ± 0.08 mb for ${\overline{\Sigma }}^{\pm }\mathrm{}\left(1385\right)\mathrm{}$. The inclusive total and differential cross sections are discussed in comparison with data at lower energies. The direct production cross sections for pseudoscalar, vector, and tensor $K$ mesons are estimated to be 2.3 ± 1.2, 3.4 ± 1.0, and 1.7 ± 0.8 mb, respectively. Direct pseudoscalar-$K$-meson production accounts for less than one-third of the total inclusive kaon production. Evidence of vector-meson dominance in inclusive meson production at high energy is indicated.