Neutron collimator design of neutron radiography based on the BNCT facility

TL;DR

This paper presents the design, simulation, and testing of a neutron collimator for neutron radiography based on BNCT reactor neutrons, demonstrating effective neutron flux and collimation ratio for imaging applications.

Contribution

It introduces a novel neutron collimator design optimized for BNCT reactor neutrons, validated through simulation and experimental testing.

Findings

Thermal neutron flux > 10^6 n/cm^2/s at collimator end

Maximum collimation ratio (L/D) is 58

Cd-ratio(Mn) is 160

Abstract

For the research of CCD neutron radiography, a neutron collimator was designed based on the exit of thermal neutron of the Boron Neutron Capture Therapy (BNCT) reactor. Based on the Geant4 simulations, the preliminary choice of the size of the collimator was determined. The materials were selected according to the literature data. Then, a collimator was constructed and tested on site. The results of experiment and simulation show that the thermal neutron flux at the end of theneutron collimator is greater than 10^6 n/cm^2/s, the maximum collimation ratio (L/D) is 58, the Cd-ratio(Mn) is 160 and the diameter of collimator end is 10 cm. This neutron collimator is considered to be applicable for neutron radiography.