GPD modules for scintillating fiber readouts

Scintillating and wavelength shifting (WLS) scintillating fibers have increasingly demonstrated advantages over traditional radiation detection/tracking in high-energy physics (HEP) experiments. High-gain, Geiger avalanche optical detectors, operated at bias voltage compatible with digital CMOS, may provide scintillating fiber readouts with single-photon sensitivity and digital-like output that may eliminate low-noise, analog amplification electronics. Using innovative designs based on high-volume manufacturing CMOS, we have recently demonstrated the feasibility of Geiger photodiode (GPD) modules with output drivers as high-detection efficiency readouts of scintillating fibers. These modules, with moderate dark count rate at room temperature, have demonstrated sub-nanosecond timing resolution and capability of detecting photon events from less than 1 Hz to 100 kHz when operated in gated mode. Using these GPD modules, low-rate cosmic muon detection with WLS fibers was demonstrated on a MINOS-style setup. Reliability evaluation showed no degradation over almost two years of operation at room temperature. Accelerated aging reliability testing predicts lifetimes up to seven years of operation at room temperature.