An experimental set-up for analysis of materials using prompt gamma neutron activation

The paper presents an experimental set-up destined to provide the main features of PGNAA equipment and to clarify many design parameters that give the performance of the method. All these considerations are valid in general, but a special attention was paid to coal. The experimental set-up consists of an Am-Be neutron source (10⁷ n/s) placed in a cylindrical vessel and a semiconductor Ge-Li detector outside the vessel. The prompt gamma spectrum is recorded and analyzed using an integrated computerized system. The MCA soft provides the digital spectrum stabilization (DSS) by choosing some reference peaks. In the second variant, the sample is placed between neutron source and detector. This arrangement was used in the case of solutions in a parallelepiped vessel. The prompt gamma spectra generally consist of two types of lines: inelastic scattering lines produced from the fast neutron reactions and capture lines produced by thermal and epithermal neutrons, Monte Carlo simulations were devoted to mapping the space and energy distributions of the neutrons produced by an Am-Be source in different media