The Mini Labyrinth Benchmark for Radiation Protection and Shielding Analysis

Abstract

The Mini Labyrinth experiment is a neutron and gamma shielding experiment currently being developed at the Slovak University of Technology, Bratislava (STU). The STU Mini Labyrinth consists of NEUTRONSTOP shielding blocks, water tank, PuBe neutron source, and graphite prism. This article describes the second construction version of the Mini Labyrinth experiment and presents the newest results of the neutron and gamma fields’ simulation and measurement. The PuBe neutron source with the emission rate of 1.06E7 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\text{n}\cdot \text{s}^{-1}$ </tex-math></inline-formula> was used in the experiment. The measurement of gamma ambient dose equivalent H*(10) and neutron count rates is performed by the Thermo Scientific RadEye portable survey meter and the SNM-11 BF3-filled corona detector. The simulation part was carried out using the state-of-the-art MCNP6 and SCALE6 MONACO stochastic calculation tools, considering the detailed geometry of the Mini Labyrinth and a combined neutron and gamma source of particles. The comparisons were performed between codes and the experiment. The propagation of cross-sectional uncertainties was investigated through the shielding analysis. Almost perfect agreements between simulation codes were achieved. The comparison with measurement suggests the further needs of room effect assessment.