title: Timing and Energy Resolution of new near-UV SiPMs coupled to LaBr3:Ce for TOF-PET.
abstract: The high light output and fast decay time of LaBr3:Ce scintillation detectors leads to excellent timing performance. To realize the potential of timing resolution with LaBr3:Ce we have investigated the performance with SiPMs, which enable 1-to-1 coupling to individual crystals, and which have been optimized for the near-ultraviolet (NUV) scintillation light emission of LaBr3:Ce. Coincidence timing resolution (CTR) of 100 ps was measured for a 4×4×5 mm3LaBr3:30%Ce crystal directly coupled to a large-area 4×4 mm2NUV-SiPM. Results show very little dependence on temperature, in the range of -20° to 20°C, and bias voltage, from 2 V to 5 V over breakdown. Optimal performance was achieved at an over-voltage (OV) range of 3 V - 5 V, at which high gain and high photon detection efficiency are achieved. Though saturation was evident at 511 keV, an energy resolution of 6.8% was measured after correcting for non-linearity. We also measured a CTR of 110 ps for a 4×4×5mm3LaBr3:5%Ce crystal and 245 ps for a 4×4×30 mm3LaBr3:5%Ce crystal using the NUV-SIPM. The poorer timing measurement for the 30-mm long crystal is due mainly to a systematic shift in the time pick-off as a function of the depth-of-interaction. The excellent temperature stability, fast rise time, high gain, and low noise of the NUV-SiPM make it a practical and highly appealing photodetector for the readout of a LaBr3:Ce TOF-PET detector.
authors.affiliation: University of Pennsylvania, Philadelphia, PA 19104 (telephone: 215-662-6964).
authors.forename: Jeffrey P
authors.initials: JP
authors.lastname: Schmall
authors.affiliation: University of Pennsylvania, Philadelphia, PA 19104 (telephone: 215-662-6964).
authors.forename: Rony I
authors.initials: RI
authors.lastname: Wiener
authors.affiliation: University of Pennsylvania, Philadelphia, PA 19104 (telephone: 215-662-6964).
authors.forename: Suleman
authors.initials: S
authors.lastname: Surti
authors.affiliation: Fondazione Bruno Kessler, Trento, Italy (telephone: +39 0461314428).
authors.forename: Alessandro
authors.initials: A
authors.lastname: Ferri
authors.affiliation: Fondazione Bruno Kessler, Trento, Italy (telephone: +39 0461314428).
authors.forename: Alberto
authors.initials: A
authors.lastname: Gola
authors.affiliation: Fondazione Bruno Kessler, Trento, Italy (telephone: +39 0461314428).
authors.forename: Alessandro
authors.initials: A
authors.lastname: Tarolli
authors.affiliation: Fondazione Bruno Kessler, Trento, Italy (telephone: +39 0461314428).
authors.forename: Claudio
authors.initials: C
authors.lastname: Piemonte
authors.affiliation: University of Pennsylvania, Philadelphia, PA 19104 (telephone: 215-662-6964).
authors.forename: Joel S
authors.initials: JS
authors.lastname: Karp