Energy Dependence of Pion Production by Protons on Nuclei

Abstract

The reactions $^{10}\mathrm{B}$($p$,${\ensuremath{\pi}}^{+}$)$^{11}\mathrm{B}$(g.s.) and $^{40}\mathrm{Ca}$($p$,${\ensuremath{\pi}}^{+}$)$^{41}\mathrm{Ca}$(g.s.) have been studied with proton beams in the energy range 140 to 200 MeV. Angular distributions at several energies, supplemented with fixed-angle cross-section data at several other energies, establish for the first time the energy dependence of these reactions in the near-threshold region.