An Attempt of improvement of positron lifetime measurement by use of - and digital methods

Hashi, Yohei; Hirade, Tetsuya  ; Suzuki, Takenori*

Positron Annihilation Lifetime was measured by - coincidence method with a digital storage cscilloscope(DSO). A photodiode was used to detect the positron injected into a sample from a source. Two sets of a photomultiplier tube and a scintillator were used to detect annihilation rays emitting to opposite directions from the sample. This - coincidence lifetime measurement was first attempt and the signal-to-noise ratio became better than the conventional lifetime measurement by - coincidence method.