Asymmetries in inclusive proton-nucleon scattering at 11.75 GeV/c

We have measured the left-right asymmetry for the inclusive production of ${\pi }^{\pm }$, $K^{\pm }$, and protons in proton-proton and proton-deuteron collisions at 11.75 GeV/c. The measurements, utilizing the polarized proton beam at the Argonne zero-gradient synchrotron, cover a wide range of kinematic variables [$u$ between 0.6 and -1.5 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ and $x$ between 0.1 and 0.9 for meson production, $t$ between -0.2 and -2.0 ${(\mathrm{G}\mathrm{e}\mathrm{V}/\mathit{c})}^2$ and $x$ between -0.25 and 0.75 for proton production]. There is considerable angular structure in the pion-production data but not in the kaon or proton processes. Proton production alone is clearly sensitive to the isotopic spin of the target particle. A simple phenomenological model of baryon-exchange dominance successfully relates the inclusive pion asymmetries to the asymmetries in backward pion-nucleon elastic scattering. A triple-Regge model for the inclusive proton asymmetries is also discussed.