Study on neutronics performance of the Soller collimator for neutron radiography based on Geant4

Soller collimators can efficiently produce thermal neutron beams with a high collimation ratio. In order to promote the application of Soller collimators in neutron radiography systems, different neutronics designs of Soller collimators are compared by using the GEANT4 program. The calculations show that the Soller collimator with square structure has best neutron beam compared with round and hexagon structure; The neutron flux is positively associated with the neutron emission area of collimator; B₄C/Al has best neutronics performance as wall material of collimator compared with Fe, Gd₂O₃ and Cd. Based on the above results, a Soller collimator with optimized parameters was compared with a traditional divergent collimator. The results show that the Soller collimator can provide higher-quality beam conditions for neutron radiography and has the potential to be used in miniaturized neutron radiography systems.