Prompt gamma ray analysis of Portland cement sample using keV neutrons with a Maxwellian energy spectrum - A Monte Carlo study

Monte Carlo calculations have been carried out to determine the prompt gamma ray yield from a Portland cement sample using keV neutrons from a ³H(p,n) reaction with a Maxwellian energy distribution with kT=52keV. This work is a part of wider Monte Carlo studies being conducted at the King Fahd University of Petroleum and Minerals (KFUPM) in search of a more efficient neutron source for its D(d,n) reaction based (2.8MeV neutrons) Prompt Gamma Ray Neutron Activation Analysis (PGNAA) facility. In this study a ³H(p,n) reaction based prompt gamma ray PGNAA setup was simulated. For comparison purposes, the diameter of a cylindrical external moderator of the ³H(p,n) reaction based PGNAA setup was assumed to be similar to the one used in the KFUPM PGNAA setup. The results of this study revealed that the optimum geometry of the ³H(p,n) reaction based setup is different from that of the KFUPM PGNAA facility. The performance of the ³H(p,n) reaction based setup is also better than that of the 2.8MeV neutrons based KFUPM facility and its prompt gamma ray yield is about 60-70% higher than that from the 2.8MeV neutrons based facility. This study has provided a theoretical base for experimental test of a ³H(p,n) reaction based setup.