Improved Neutron Diagnostics using Compton Suppression Gamma-ray Spectrometer with Self-absorption correction

Minimizing measurement error of the neutron activation system is very important, because the error of activation system must affect the measurement of other diagnostic systems. In this study, the encapsulated indium samples were installed and irradiated by the neutrons released from the nuclear fusion reactions in KSTAR. The Compton suppression gamma ray spectrometer, which can suppress the expected background, noise signal and Compton scatterings was used to measure the gamma rays of neutron activated samples. Additionally, indium sample gamma ray self-absorption effect has been estimated. The Compton suppression system has been used to detect the gamma rays from neutron activated indium foils for reducing the measurement errors. From the experimental results, the statistical error was decreased by Compton suppression system. It was found that the system could reduce the measurement error effectively. Therefore, it is concluded that introducing the Compton suppression system for NAS, more accurate measurement is possible