Single pion production in π+p interactions at 895, 945, 995 and 1040 MeV/c

Cross sections for pion production processes are presented. For the π+πop and π+π+n channels resonance fractions, determined using simple models which ignore interference effects, are given and the significance of the observed low peak of the Δ (1236) is discussed. Strong production of the πΔ intermediate state in P and D wave orbital angular momentum states seems to be required.