Photoneutrons–neutrons produced through photonuclear reactions–play a critical role in radiation transport scenarios involving high-energy gamma sources, electron accelerators, and nuclear reactors. Accurate modeling of photoneutron production and transport is still a challenging problem, due to limitations in photonuclear data and the sensitivity of simulations to the choice of physics models. In this study, we present a comprehensive investigation of photoneutron generation using three state-of-the-art Monte Carlo codes–MCNP6®, PHITS, and TRIPOLI-4®–each coupled with two major nuclear data libraries: ENDF/B-VIII.1 and JENDL-5. Photon-induced neutron production is analyzed across 49 elemental targets for incident photon energies from the photonuclear threshold up to 30 MeV, encompassing the Giant Dipole Resonance (GDR) region. Key observables–photoneutron currents, energy spectra, and angular distributions–are systematically evaluated as a function of atomic number. The resulting dataset serves as a reference benchmark for simulation validation, informs future improvements in photonuclear modeling and nuclear data, and supports broader applications in theoretical and experimental nuclear physics.
Garnaud et al. (2026) studied this question.