Characterization of a silicon photo-multiplier array with summing board as a photo-multiplier tube replacement in organic scintillator assemblies

Melinda Sweany; Peter Marleau; Chris Allwork; Gene Kallenbach; Steven Hammon

doi:10.1016/j.nima.2019.163118

paper

Characterization of a silicon photo-multiplier array with summing board as a photo-multiplier tube replacement in organic scintillator assemblies

arXiv:1906.08258 · doi:10.1016/j.nima.2019.163118

Abstract

We report on the energy, timing, and pulse-shape discrimination performance of cylindrical 5 cm diameter x 5 cm thick and 7 cm diameter x 7 cm thick {\it trans}-stilbene crystals read out with the passively summed output of three different commercial silicon photo-multiplier arrays. Our results indicate that using the summed output of an 8x8 array of SiPMs provides performance competitive with photo-multiplier tubes for many neutron imaging and correlated particle measurements: for the 5x5 cm crystal read out with SensL's ArrayJ-60035\_64P-PCB, which had the best overall properties, we measure the energy resolution as 13.6 $\pm$ 1.8\% at 341 keVee, the timing resolution in the 100--400 keVee range as 277 $\pm$ 34 ps, and the pulse-shape discrimination figure-of-merit as 2.21 $\pm$ 0.03 in the 230--260 keVee energy range. These results enable many scintillator-based instruments to enjoy the size, robustness, and power benefits of silicon photo-multiplier arrays as replacement for the photo-multiplier tubes that are predominantly used today.