A novel gamma-ray detector with submillimeter resolutions using a monolithic MPPC array with pixelized Ce:LYSO and Ce:GGAG crystals

摘要: Abstract We have developed a large-area monolithic Multi-Pixel Photon Counter (MPPC) array consisting of 4×4 channels with three-side buttable package. Each channel has photosensitive area 3×3 mm2 and 3600 Geiger mode avalanche photodiodes (APDs). For typical operational gain 7.5×105 at +20 °C, fluctuation over the entire MPPC device is only ± 5.6 % , dark count rates (as measured 1 p.e. level) amount to ≤ 400 kcps per channel. first fabricated gamma-ray camera one-to-one coupling Ce-doped ( Lu Y ) 2 SiO 4 O (Ce:LYSO) crystal (4×4 3×3×10 mm3 crystals). Energy time resolutions 11.5 0.5 (FWHM 662 keV) 493 22 ps were obtained, respectively. When using charge division resistor network, which compiles signals into four position-encoded analog outputs, ultimate positional resolution estimated as 0.19 mm in both X directions, while energy 10.2 0.4 (FWHM) was obtained. Finally, we submillimeter Ce:LYSO Gd 3 Ga Al 12 (Ce:GGAG) scintillator matrices each 1.0×1.0, 0.7×0.7 0.5×0.5 mm2 pixels, further improve spatial resolution. In all types Ce:GGAG matrices, clearly resolved position histograms when irradiated by 137Cs source. The for 662 keV gamma-rays matrix 14.3 . These results suggest excellent potential its use high medical imaging device, particularly positron emission tomography (PET).