Thin YAP:Ce and LaBr3:Ce scintillators as proton detectors of a thin-film proton recoil neutron spectrometer for fusion and spallation sources applications

Two thin inorganic scintillators based on YAP and LaBr3 crystals (1 in. diameter × 0.1 in. height) have been used for proton measurements at the Uppsala tandem accelerator in the energy range 4–8 MeV. Measurements show a comparable good energy resolution for the two detectors, better than 2% (FWHM) for 8 MeV protons, which compares to 3.8% (LaBr3) and 3.7% (YAP) obtained at the 1.3 MeV peak of a 60Co γ-ray source. The main advantages of these crystals are a fast scintillation time (less than 30 ns), an excellent light yield and the capability to operate in large neutron background, which make them ideal candidates as proton detectors of a thin-film proton recoil neutron spectrometer for application on fusion experiments and fast neutron spallation sources.