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arXiv · 1711.06742

Measurements and Monte-Carlo simulations of the particle self-shielding effect of B4C grains in neutron shielding concrete

D. D. DiJulio·C. P. Cooper-Jensen·I. Llamas-Jansa·S. Kazi·P. M. Bentley
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Abstract

A combined measurement and Monte-Carlo simulation study was carried out in order to characterize the particle self-shielding effect of B4C grains in neutron shielding concrete. Several batches of a specialized neutron shielding concrete, with varying B4C grain sizes, were exposed to a 2 Å neutron beam at the R2D2 test beamline at the Institute for Energy Technology located in Kjeller, Norway. The direct and scattered neutrons were detected with a neutron detector placed behind the concrete blocks and the results were compared to Geant4 simulations. The particle self-shielding effect was included in the Geant4 simulations by calculating effective neutron cross-sections during the Monte-Carlo simulation process. It is shown that this method well reproduces the measured results. Our results show that shielding calculations for low-energy neutrons using such materials would lead to an underestimate of the shielding required for a certain design scenario if the particle self-shielding effect is not included in the calculations.

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D. D. DiJulio, C. P. Cooper-Jensen, I. Llamas-Jansa, S. Kazi, P. M. Bentley. 2019-07-15. Measurements and Monte-Carlo simulations of the particle self-shielding effect of B4C grains in neutron shielding concrete. https://doi.org/10.1016/j.radphyschem.2018.01.023

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