Performance of thin long scintillator strips of GSO:Ce, LGSO:Ce and LuAG:Pr for low energy γ-rays

Abstract Interest in fibers or strips of single crystalline scintillators is increasing for their possible applications in fine-segmented particle detectors for particle physics experiments as well as γ-ray detectors for medical diagnoses. We compared 2×2×100 mm 3 strips of Gd 2 SiO 5 (GSO):Ce, Lu 1.9 Gd 0.1 SiO 5 (LGSO):Ce, and Lu 3 Al 5 O 12 (LuAG):Pr single crystals for 0.511 MeV γ-rays with respect to the effective light attenuation length λ a , light yield LY, FWHM energy resolution Δ E / E and rms position resolution σ ( z ) of the injection position z along the length. The obtained result was ( λ a , LY, Δ E / E , σ ( z ))=(128 mm, 380 phe/MeV, 17.7%, 8.7 mm) in GSO:Ce, (509 mm, 1760 phe/MeV, 12.2%, 10.9 mm) in LGSO:Ce, and (171 mm, 690 phe/MeV, 15.0%, 8.9 mm) in LuAG:Pr. The z position was obtained independently from the pulse height ratio as well as the timing difference between both ends of the strip. The latter method gave comparable or even smaller σ ( z ) than the former only in LGSO:Ce having both large LY and fast rise time. The λ a in the 100 mm long GSO:Ce strip was found to be twice as large as that in the 200 mm long one [1] with the same cross-section. To obtain good Δ E / E and σ ( z ), large light yield, fast rise time, and moderately large attenuation length are important for the scintillators.