Measurements and Monte-Carlo simulations of the particle self-shielding effect of B4C grains in neutron shielding concrete. (June 2018)

• Record Type: Journal Article
• Authors: DiJulio, D.D.; Cooper-Jensen, C.P.; Llamas-Jansa, I.; Kazi, S.; Bentley, P.M.
• Is Part Of: Radiation physics and chemistry. Volume 147(2018:Jun.)
• Page Start: 40
• Page End: 44
• Publication Date: 2018-06
• Subjects: Neutron shielding concrete -- Particle Self-Shielding effect -- Geant4; Radiation chemistry -- Periodicals; Radiometry -- Periodicals; Radiation -- Periodicals; Chimie sous rayonnement -- Périodiques; 539.2
• DOI: 10.1016/j.radphyschem.2018.01.023
• Languages: English
• ISSNs: 0969-806X

Abstract

Abstract: A combined measurement and Monte-Carlo simulation study was carried out in order to characterize the particle self-shielding effect of B4 C grains in neutron shielding concrete. Several batches of a specialized neutron shielding concrete, with varying B4 C 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. Abstract : Highlights: Specialized shielding concrete, containing different B4 C grain sizes, was produced. The concrete was exposed to neutrons to study the particle self-shielding effect. A patch for Geant4 was created to include the particle self-shielding effect. Comparison between the simulations and measurements validates the use of this method.