Speaker
Description
Conventional X-ray human inspection systems – security scanners – in airports, prisons, and other special guarded places are based on an integration mode scintillation detector. Usually, it consists of an array of PIN-photodiodes coupled with scintillators. The detector accumulates scintillation signals during the integration time. Thus, the output detector response represents an integral or average measure of all detected X-ray photons, i.e. all direct and scattered events with different energies. SiPM-based scintillation detectors have already been considered as potential candidates for X-ray imaging of integration and counting modalities [1], [2].
We assume that an ability to count X-ray photons with high efficiency and energy resolution is of high importance for precise and comprehensive imaging based on the spectral analysis in a number of security applications, especially with respect to the low dose human inspection.
Therefore, we proposed and developed the SiPM-based fast scintillation detector operateing in counting mode to increase the image quality and decrease the absorbed dose for the human body.
Prototyping the detector, we developed 1D 16 channel array of 3x3x5 mm2 GAGG scintillators coupled with 3x3 mm2 KETEK SiPMs. The array is connected to our homemade 18 channel front-end analog electronics board. It provides a voltage supply for SiPMs and the SiPM pulse shaping. Finally, the whole signal waveforms are digitized by the 4 channel Spectrum M2i.2031 analog-to-digital streaming PCI board [3] and analyzed by a specially developed software.
The first results of characterization, experimental studies, and measurements of SiPM-based X-ray spectral counting detector with a conventional X-ray tube and Am-241 source will be presented.
[1] S. Vinogradov, A. Arodzero, and R. C. Lanza, “Performance of X-ray detectors with SiPM readout in cargo accelerator-based inspection systems,” in 2013 IEEE Nuclear Science Symposium and Medical Imaging Conference (2013 NSS/MIC), 2013, pp. 1–6.
[2] Prekas, G.; Sabet, H.; Bhandari, H.H.; Derderian, G.; Robertson, F.; Kudrolli, H.; Stapels, C.J.; Christian, J.; Kleinfelder, S.; Cool, S.; D'Aries, L.J.; Nagarkar, V.V., "Direct and indirect detectors for X-ray photon counting systems," in Nuclear Science Symposium and Medical Imaging Conference (NSS/MIC), 2011 IEEE, pp.1487-1493, 23-29 Oct. 2011.
[3] http://spectrum-instrumentation.com/en/m2i2031
