Time resolution of stilbene coupled to silicon photomultipliers for use in a handheld dual particle scatter camera

Two stilbene crystals were coupled to low-noise silicon photomultipliers (SiPMs) to assess the assemblies' time resolution for use as elements in a handheld dual-particle scatter camera. Pulses were digitized from a measurement of Na-22 and digital constant fraction discrimination (CFD) was performed to determine the time of each pulse. The crystals were then coupled to photomultiplier tubes (PMTs) and the measurement was repeated. The full width at half max (FWHM) of the time-difference distributions was used to determine the time resolution of the detector assemblies. The time resolution when using the SiPMs was better than 1 ns and comparable to that of assemblies using PMTs.