Study on Thermal Neutron Sensitivity of Boron-Lined Ionization Chamber

With the development of science and technology, neutron detection plays an increasingly important role in many fields, such as national defense security, medical imaging and aerospace. Gas detector is a commonly used neutron detector. It takes gas as the working medium and produces electrical signal by ionization effect of incident particles. In recent years, as the expensive price of 3He gas detector, and environmental hazard of BF3 gas detector, the boron-lined ionization chamber, which is developed to replace BF3 gas detector, has been widely used. The structure size, thickness of boron lining and the composition of working gas greatly influence the sensitivity of the boron-lined ionization chamber, while the sensitivity is one of the important indicators to evaluate its application site and decide the choice of subsequent electronic analysis equipment. In this paper, Monte Carlo simulation software, Geant4, is used to study the variation of thermal neutron sensitivity of boron-lined ionization chamber under different technical parameters (detector structure size, boron lining thickness, composition of working gas), which provides reference for the structure design of boron-lined ionization chamber.