Recent results in scintillation detection with silicon avalanche photodiodes

An investigation of silicon avalanche photodiodes (APDs) in scintillation detection for potential applications in medical imaging and nuclear spectroscopy is reported. Experimental measurements were performed on bismuth germanate (BGO), CdWO₄, plastic, NaI(Tl) and CsI(Tl) scintillators, geometrically optimized for light collection. Results show the advantages of a solid-state photodetector having an internal gain for the detection of low-energy gamma and X-rays. When coupled to CsI(Tl), X-ray energies as low as 5.9 keV can be discriminated from the noise. The results demonstrate the suitability of APDs for many applications in scintillation detection and, in particular, their distinct advantage over other unity gain photodiodes for the detection of low-energy radiation in scintillation spectroscopy: unequaled energy thresholds have been demonstrated