Analysis of the energy spectrum of photoneutrons for the $(\gamma, xn)$ reaction within the formalism of statistical multistep compound processes

The energy spectra of photoneutrons generated in the $(\gamma, xn)$ reaction on medium and heavy nuclei in the region of dipole giant resonance were analyzed. The analysis was carried out within tl1e framework of the generalized model of multipole giant resonance decay using the formalism of statistical multistep compound processes and allowing for the yield multiplicity. The nucleons were explicitly separated into two types (neutrons and protons). The emission of two neutrons was correctly taken into account. The results of calculations of photoneutron spectra for the nuclei $^{115}In (E_{\gamma}^{max} = 28 MeV)$, $^{181}Та (E_{\gamma}^{max} = 19 MeV)$, and $^{209}Bi (E_{\gamma}^{max} =20 MeV)$ are presented and compared with experiment.