Abstract
Recently gamma ray detection technologies become very important in the fields of medical application, space, and environment. Pixelated detectors and electronics are necessary to achieve high-resolution gamma ray detectors. Especially high resolution PET (positron emission tomography) system has been a driving force for developing pixel gamma-ray detectors. A pixel gamma detector is composed of granulated crystals and photo-detectors with highly integrated circuits (ASIC) to process the large number of channels. Recent development of these technologies is reviewed here.
