Measurements of the Spectral and Dose Characteristics of the Neutron Field Behind the Biological Shielding of the IREN Source for 60-MeV Electrons

Results of the measurements of neutron spectra at two points at the intense resonance neutron source (IREN) of the JINR’s Laboratory of Neutron Physics are presented. Powerful neutron fluxes are obtained using an electron accelerator and the thick tungsten target, in which neutrons are produced by bremsstrahlung gamma-quanta of electrons hitting the target. The tungsten target is placed in a cylindrical vessel filled with water. Neutron spectra were obtained using a multisphere Bonner spectrometer at two points behind biological shielding. Based on the spectra obtained, the effective neutron dose rates at the measurement points were determined, which is of importance both for assessing the radiation situation at IREN and for comparison with the readings of neutron dosimeters of the automated radiation monitoring system.