Comparison of Lu 3Al 5O 12:Pr 3+ and Bi 4Ge 3O 12 scintillators for gamma-ray detection

• Published in: Radiation measurements Vol. 47; no. 1; pp. 1 - 5
• Main Authors: Chewpraditkul, Weerapong, Sreebunpeng, Krittiya, Nikl, Martin, Mares, Jiri A., Nejezchleb, Karel, Phunpueok, Akapong, Wanarak, Chalerm
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 2012
• Subjects: BGO; Energy resolution; Light yield; LuAG:Pr; Scintillation detectors; Energy resolution; LuAG:Pr; Scintillation detectors; BGO; Light yield
• ISSN: 1350-4487; 1879-0925
• DOI: 10.1016/j.radmeas.2011.08.023

The scintillation properties of Lu 3Al 5O 12:Pr 3+ (LuAG:Pr) single crystal grown by the Czochralski method with praseodymium concentration of 0.19 mol% were investigated. For a comparison, a good quality Bi 4Ge 3O 12 (BGO) single crystal grown by Bridgman method was also studied. The light yield and energy resolution were measured using photomultiplier tube (XP5200B PMT) readout. Moderate light yield of 15,900 photons per MeV was measured for the LuAG:Pr(0.19%) crystal. For 662 keV gamma rays ( 137Cs source), an energy resolution of 6.5% obtained for LuAG:Pr(0.19%) is much better than that of 9.0% obtained for BGO. The light yield non-proportionality and energy resolution versus energy of gamma rays were measured and the intrinsic resolution of the crystals was determined after correcting the measured energy resolution for PMT statistics. The LuAG:Pr(0.19%) showed a good proportionality of the light yield within 5% over the energy range from 1274.5 keV down to 32 keV, which is much better than that of 14% for BGO. The photofraction was determined at 320 and 662 keV for both crystals and compared with the ratio of the cross-sections for the photoelectric effect to the total one calculated using WinXCOM program. ► Gamma-ray detection properties of LuAG:Pr(0.19%) were compared with those of BGO. ► It shows light yield of 15,900 ph/MeV with a very good proportionality. ► At 662 keV, its energy resolution of 6.5% is better than that of 9.0% for BGO. ► Photofraction was determined at 320 and 662 keV for both crystals. ► BGO shows higher photofraction due to its higher Z eff and density.