Positron annihilation lifetime measurement by use of LSO scintillators

Hirade, Tetsuya  ; Minei, Shuntaro; Sakai, Hiroaki

LSO scintillators have high density, short lifetime of light emission and high light strength, and that are applied for PET. The commonly used positron annihilation lifetime measurement system has BaF scintillators, because BaF scintillator has very fast light emission which is a great advantage for a good time resolution. On the other hand, LSO has a advantage on the high counting rate. We have tried to use LSO scintillators for the positron annihilation lifetime measurements. The system with LSO scintillators gave 5 times higher counting rate than with BaF scintillators, and 315ps time resolution (FWHM) which is just 50 ps worth than BaF. The irradiation effects on the sample for long measurement time is not negligible and then LSO scintillators provide a better system for these measurements.