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Choopan Dastjerdi M.H.,Mokhtari J.,Toghyani M. 한국원자력학회 2023 Nuclear Engineering and Technology Vol.55 No.12
In this research, a prompt gamma neutron activation analysis (PGNAA) system is designed and constructed based on the use of a low power research reactor. For this purpose, despite the fact that this reactor did not include beam tubes, a thermal neutron beam line is installed inside the reactor tank. The extraction of the beam line from inside the tank made it possible to provide the neutron flux from the order of 106 n.cm-2.s-1. Also, because the beam line is installed in a tangential position to the reactor core, its gamma level has been minimized. Also, a suitable radiation shield is considered for the detector to minimize the background radiation and prevent radiation damage to the detector. Calculations and measurements are done in order to characterize this system, as well as spectrometry of several samples. The results of evaluations and experiments show that this system is suitable for performing PGNAA
Z. Gholamzadeh, E. Bavarnegin,E. Bavarnegin,M.Lamehi Rachti,S.M. Mirvakili,M.H.Choopan Dastjerdi,H. Ghods,A. Jozvaziri,M. Hosseini 한국원자력학회 2018 Nuclear Engineering and Technology Vol.50 No.1
The neutron powder diffractometer (NPD) is used to study a variety of technologically important andscientifically driven materials such as superconductors, multiferroics, catalysts, alloys, ceramics, cements,colossal magnetoresistance perovskites, magnets, thermoelectrics, zeolites, pharmaceuticals,etc. Monte Carloebased codes are powerful tools to evaluate the neutronic behavior of the NPD. In thepresent study, MCNPX 2.6.0 and Vitess 3.3a codes were applied to simulate NPD facilities, which couldbe equipped with different optic devices such as pyrolytic graphite or neutron chopper. So, the MonteCarloebased codes were used to simulate the NPD facility of the 5 MW Tehran Research Reactor. Thesimulation results were compared to the experimental data. The theoretical results showed goodconformity to experimental data, which indicates acceptable performance of the Vitess 3.3a code in theneutron optic section of calculations. Another extracted result of this work shows that application ofneutron chopper instead of monochromator could be efficient to keep neutron flux intensity higherthan 106 n/s/cm2 at sample position.