Search for the Δ++ component in the C ground state using the C(γ,π+p) reaction

Abstract The differential cross section for the 12 C( γ , π + p ) reaction has been measured in the Δ (1232) resonance region at high recoil momenta of the residual nuclear system. The data are analyzed under the assumption that the formation of the π + p pairs may be interpreted as a γΔ ++ → π + p process which takes place on a Δ ++ preexisting in the target nucleus. Estimates of the Δ ++ momentum distribution ρ Δ ++ ( p )=0.17 fm 3 for a mean momentum p =300±49 MeV/ c as well as the number of Δ isobars per nucleon N Δ =0.017 were obtained for 12 C.