Inclusive study of strange-particle production in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>pp</mml:mi></mml:math>interactions at 405 GeV/<i>c</i>

Abstract

We have studied inclusive ${K}_{S}^{0}$, $\ensuremath{\Lambda}$, and $\overline{\ensuremath{\Lambda}}$ production and strange-resonance production in the reactions $\mathrm{pp}\ensuremath{\rightarrow}({K}_{S}^{0}, \ensuremath{\Lambda}, or \overline{\ensuremath{\Lambda}})+{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}+\mathrm{anything}$ at 405 GeV/c. The observed cross sections are 7.43 \ifmmode\pm\else\textpm\fi{} 0.45 mb for ${K}_{S}^{0}$, 4.01 \ifmmode\pm\else\textpm\fi{} 0.35 mb for $\ensuremath{\Lambda}$, and 0.63 \ifmmode\pm\else\textpm\fi{} 0.12 mb for $\overline{\ensuremath{\Lambda}}$. From the analyses of the effective-mass distributions for the (${K}_{S}^{0}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$), ($\ensuremath{\Lambda}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$), and ($\overline{\ensuremath{\Lambda}}{\ensuremath{\pi}}^{\ifmmode\pm\else\textpm\fi{}}$) systems, the resonance production cross sections are determined as 4.1 \ifmmode\pm\else\textpm\fi{} 1.0 mb for ${K}^{*+}(890)$, 3.6 \ifmmode\pm\else\textpm\fi{} 1.0 mb for ${K}^{*\ensuremath{-}}(890)$, 3.4 \ifmmode\pm\else\textpm\fi{} 1.7 mb for ${K}^{*\ifmmode\pm\else\textpm\fi{}}(1420)$, 0.67 \ifmmode\pm\else\textpm\fi{} 0.12 mb for ${\ensuremath{\Sigma}}^{+}(1385)$, 0.45 \ifmmode\pm\else\textpm\fi{} 0.09 mb for ${\ensuremath{\Sigma}}^{\ensuremath{-}}(1385)$, and 0.25 \ifmmode\pm\else\textpm\fi{} 0.08 mb for ${\overline{\ensuremath{\Sigma}}}^{\ifmmode\pm\else\textpm\fi{}}(1385)$. 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 \ifmmode\pm\else\textpm\fi{} 1.2, 3.4 \ifmmode\pm\else\textpm\fi{} 1.0, and 1.7 \ifmmode\pm\else\textpm\fi{} 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.