Photodisintegration of Quasifree Nucleon-Nucleon System in the Beryllium Nucleus

Momentum spectra of protons in the reaction of γ+Be→p + anything in the incident energy range from 180 to 420 MeV were measured. The spectrum obtained shows two peaks which are interpreted to be due to the protons in reactions γ+``N''→p+π and γ+``d''→p+n, where $``N''$ and $``d''$ are the quasifree nucleons and neutron-proton systems, respectively, in the beryllium nucleus.