Analysis of neutron beam quality control test items in boron neutron capture therapy (BNCT) equipment / 中华放射医学与防护杂志

ABSTRACT

Objective:To provide reference for establishing the testing method for quality control of neutron beam in boron neutron capture therapy (BNCT) equipment in China by testing the radiation characteristic parameters and dosimetry characteristic parameters of epithermal neutron beam in hospital neutron irradiator (IHNI).Methods:By comparing the uncertainties in the result of various test items with the deviation values recommended by the European Joint Research Center (EC-JRC), the feasibility of the relevant of testing method was analyzed and evaluated.Results:The uncertainty in epithermal neutron fluence rate was 2.7%. The uncertainty in ratio of thermal to epithermal neutron fluence rate was 3.1%. The uncertainty in ratio of fast neutron air kerma to epithermal neutron fluence rate was 9.3%. The uncertainty in ratio of gamma air kerma to epithermal neutron fluence rate was 8.7%. The uncertainty in spatial distribution of neutron fluence rate was 2.7%. The uncertainty in thermal neutron fluence rate in phantom was 1.8%. The uncertainty in neutron and gamma-ray dose rate in phantom was 17.1% and 4.0%, respectively.Conclusions:The uncertainty in neutron dose rate measurement result in phantom is higher, and further research is needed to improve the accuracy of the testing method. The uncertainty in the measurement result of other test items is lower, and the accuracy of the test result is expected to meet the allowable deviation value recommended by the European Joint Research Center, and the test method is feasible.