Neutron/gamma pulse shape discrimination in plastic scintillators: Preparation and characterization of various compositions

Pauline Blanc (1, 2) , Matthieu Hamel (1) , Chrystèle Dehé-Pittance (1) , Licinio Rocha (1) , Robert B. Pansu (2) , Stéphane Normand (1)

1 LCAE (CEA, LIST) - Laboratoire Capteurs et Architectures Electroniques (CEA, LIST)
2 PPSM - Laboratoire de Photophysique et Photochimie Supramoléculaires et Macromoléculaires

This work deals with the preparation and evaluation of plastic scintillators for neutron/gamma pulse shape discrimination (PSD). We succeeded in developing a plastic scintillator with good neutron/gamma discrimination properties in the range of what is already being commercialized. Several combinations of primary and secondary fluorophores were implemented in chemically modified polymers. These scintillators were fully characterized by fluorescence spectroscopy and under neutron irradiation. The materials proved to be stable for up to 5 years without any degradation of PSD properties. They were then classified in terms of their PSD capabilities and light yield. Our best candidate, 28.6 wt% of primary fluorophore with a small amount of secondary fluorophore, shows promising PSD results and is particularly suited to industrial development, because its preparation does not involve the use of expensive or exotic compounds. Furthermore, even at the highest prepared concentration, high stability over time was observed. As a proof of concept, one sample with dimensions 109 mm ∅ × 114 mm height (approx 1 L) was prepared.

Mots clés: Gamma ray; plastic scintillator; neutron/gamma discrimination; instrumentation; nuclear detector; pulse shape discrimination (PSD); neutron detection; fluorescence; scintillation 26

Domaines: Instrumentations et Détecteurs [physics.ins-det]; Physique Nucléaire Expérimentale [nucl-ex]

Pauline Blanc, Matthieu Hamel, Chrystèle Dehé-Pittance, Licinio Rocha, Robert B. Pansu, et al.. Neutron/gamma pulse shape discrimination in plastic scintillators: Preparation and characterization of various compositions. Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, 2014, 750, pp.1-11. ⟨10.1016/j.nima.2014.02.053⟩. ⟨hal-01082176⟩