Timing performance of large area SiPMs coupled to LYSO using dark noise compensation methods

In this paper we show new coincidence resolving time measurements with large area SiPMs coupled to LYSO scintillators in which we compensate the baseline fluctuation generated by dark events. In particular, we present experimental data obtained with the Differential Leading Edge Discriminator (DLED) method in which the arrival time of the event is not extracted directly from the signal but rather from the difference between the signal and its delayed replica. Dark events are effectively compensated allowing very low thresholds to be set. Timing performances have been measured by the DLED method on different SiPM-scintillator configurations at various temperatures. As an example, coupling a 4×4mm² SiPM to a 3×3×5mm³ LYSO crystal, a coincidence resolving time of 190ps FWHM was obtained at room temperature.