Features of pulse shape discrimination capability of organic heterogeneous scintillators

This work studies the PSD (pulse shape discrimination) capability of organic heterogeneous (polycrystalline and composite) scintillation materials, i.e. their ability to separate ionizing radiations by the difference in the form of scintillation pulses generated by the radiations with different specific energy losses (dE/dx). It analyses the parameters describing the formation of a scintillation pulse, the knowledge of which is useful for the design and creation of electronic units optimally solving the PSD problem for a given scintillator. The comparative analysis of the results shows that the PSD capability of organic heterogeneous scintillators is close to the corresponding values for reference single crystals. Stilbene-based materials have the best PSD capability to a separate detection of the ionizing radiations with different values of dE/dx. Organic heterogeneous scintillators based on stilbene and p-terphenyl are promising candidates for development of effective detectors for the ionizing radiations with high dE/dx-values (e.g., fast neutrons and alpha particles) in a presence of gamma background.