Speaker
Description
The increased demand for neutron detection has prompted investigations of new techniques for achieving this goal. One method of realising this depends on neutron-induced reactions in a detector crystal with charged particles in the exit channel. Particle mass and charge influence its LET, which ultimately affects the dominant photo-emission mechanism in the used scintillator. This property can be leveraged in lanthanum-halide detectors, such as LaBr$_3$(Ce), in conjunction with pulse shape discrimination (PSD) and/or amplitude Fourier shape discrimination (AFSD). By analysing the waveform from LaBr$_3$(Ce) using PSD and AFSD, a distinction can be made between different particles. Regrettably, lanthanum halides are intrinsically contaminated with actinium-227, due to the similarities in chemical properties between Ac and La, making them difficult to separate. Actinium's decay chain contributes many alpha particles to the intrinsic spectrum of LaX detectors, making it more difficult to quantify neutron information with certainty, especially since the contamination is rarely reported by manufacturers.
In this study, the contamination of 10 separate LaBr$_3$(Ce) detectors from one manufacturer was investigated using PSD and AFSD to see the relative difference in the contamination levels between different crystals. Preliminary results will be presented alongside a brief explanation of both PSD and AFSD. Some experimental difficulties will be discussed, including the need for a sufficiently high digitiser sampling rate.