High energy X-ray photon counting imaging using linear accelerator and silicon strip detectors

Abstract

A photon counting imaging detector system for high energy X-rays is developed for on-site non-destructive testing of thick objects. One-dimensional silicon strip (1mm pitch) detectors are stacked to form a two-dimensional edge-on module. Each detector is connected to a 48-channel application specific integrated circuit (ASIC). The threshold-triggered events are recorded by a field programmable gate array based counter in each channel. The detector prototype is tested using 950kV linear accelerator X-rays. The fast CR shaper (300ns pulse width) of the ASIC makes it possible to deal with the high instant count rate during the 2μs beam pulse. The preliminary imaging results of several metal and concrete samples are demonstrated.