Multipion and strange-particle photoproduction on protons at energies up to 5.8-GeV

In a study of photoproduction at photon energies between 0.3 and 5.8 GeV in a hydrogen bubble chamber, approximately 1.7 million pictures containing about 31 000 events with three or more outgoing charged particles were analyzed. This is the second of two final reports on this experiment. Distributions of effective masses are given for the reactions γp→N3π, N4π, N5π. Cross sections for the production of Δ(1236) and ρ via γp→Δρ, Δ2π, Δ3π, Δ4π, Nπρ, and N2πρ and of various other reactions are reported. From the reaction γp→Δ++ρ−, an upper limit for the radiative decay width of ρ−, Γ(ρ−→π−γ)<0.24 MeV, is obtained (90% confidence). For the four-pion decay mode of the ρ0, an upper limit of Γ(ρ0→π+π+π−π−)Γ(ρ0→π+π−)<0.0015 is found (90% confidence). The photoproduction of strange particles is discussed and cross sections for γp→ΛK+, ΣK, ΛKπ, ΣKπ, and ΛKππ are presented. Production of Σ(1385) was observed.