The cross sections of the reactions (γ,p), (γ,pn), and (γ,pp) are measured for ${}_{}{}^1{}_{}{}^{}\mathrm{H}$, ${}_{}{}^2{}_{}{}^{}\mathrm{H}$, ${}_{}{}^9{}_{}{}^{}\mathrm{Be}$, ${}_{}{}^{12}{}_{}{}^{}\mathrm{C}$, and ${}_{}{}^{16}{}_{}{}^{}\mathrm{O}$ in the Δ(1232) resonance region by use of a tagged photon beam. Protons emitted at ${\theta }_{\mathrm{p}=30\mathrm{}}$° are measured by a magnetic spectrometer, and the other neutrons or protons are measured by an array of scintillation counter hodoscopes. From the present experiment, it is concluded that the reactions, γ+‘‘N’’→p+π and γ+‘‘pn’’→p+n, contribute dominantly to the (γ,p) reaction in this energy region, where ‘‘N’’ denotes the nucleon and ‘‘pn’’ denotes the pn system in the nucleus.

• Received 30 June 1986

DOI:https://doi.org/10.1103/PhysRevC.35.1828