Theoretical analysis of the formation of η mesic nuclei in γ + A → N + ηA' reactions

A model that describes the formation of η mesic nuclei in the γ + A → N + ηA' reactions is formulated on the basis of the quasifree meson photoproduction on nuclei and the concept of a meson-nucleus optical potential. The amplitude of this reaction involving more than four nucleons is obtained in the general form within the nuclear shell model featuring intermediate coupling. The dependences of the cross sections for these reactions on the excitation levels of η mesic nuclei, on the discrete excitation levels of the nucleonic cores of these nuclei, on the type of emitted nucleon, and on the final-state interaction are analyzed for the incident-photon energies from the reaction threshold to 1 GeV