Advantages of off-line analysis of digitally recorded pulses in case of neutron-gamma discrimination in scintillators

Many modern digital analyzers offer the ability to record raw pulses from ionizing radiation detectors. We use this opportunity to investigate the effectiveness of Charge Comparison Method in Pulse Shape Discrimination of neutron and gamma radiation measured with organic glass scintillator and trans-stilbene. The idea of software for automated off-line analysis of digitally recorded data is briefly described. We discuss the difference between Leading Edge and Constant Fraction Discrimination triggering methods and we propose triggering on pulse maximum as an alternative. We observe that the starting point of charge integration gates has major impact on Figure of Merit values, therefore it is important to choose it carefully and report it with other Charge Comparison Method parameters to keep comparison between scintillators reliable. Figure of Merit has a limited usage, so Relative Height of Minimum is proposed as an additional indicator of neutron-gamma discrimination effectiveness in practical applications.