Comparison of the time resolution of a fine-mesh (HP R7761-70) to a standard linear (HP R2083) photomultiplier

This study compared the time-of-flight resolution of a scintillator counter equipped with magnetic-resistant fine-mesh R7761-70 photomultipliers with that of ordinary fast R2083 photomultipliers. The data was obtained using the 45 MeV proton beam of the MC50 Cyclotron at the Korea Institute of Radiological and Medical Sciences. The R7761-70 and R2083 time-of-flight resolutions were determined using two different methods to be 18.3±0.064 and 17.4±0.049 ps (18.3±0.064 and 17.1±0.049 ps). The average ratio was σTOFR7761‐70/σTOFR2083≈1.06±0.064. The results demonstrate that fine-mesh photomultipliers can be used for precise timing.