The engineering aspects of a nine-channel digital radiographic system developed for bioimaging research, based on high gas pressure ionography and kinestatic principles, are presented. The research imaging system uses a pulsed x-ray beam which allows one to study simultaneously the ionic signal characteristics at 10 different ionization sites along the drift axis. This research imaging detector system allows one to investigate methods to improve the detection and image quality parameters as part of the development of a large scale prototype medical imaging system.

In this paper, modulation transfer function and image noise measurements are presented for Kinestatic Charge Detectors employing high-pressure Kr gas doped with NH3 and CO2. Kr improves spatial resolution over Xe because, at equal x-ray mean free path, it has both reduced fluorescence reabsorption and reduced electron range. NH3 eliminates mobility dispersion (disparate ionic mobilities from multiple charge carriers) caused by gas impurities. CO2 reduces electron attachment and thus ion-ion recombination because it lowers the electron temperature, thereby increasing electron drift velocity via the Ramsauer effect.