TY - CONF
T1 - Digital CZT detector system for high flux energy-resolved X-ray imaging
AU - Principato, Fabio
AU - Gerardi, Gaetano
AU - Abbene, Leonardo
AU - Veale, Matthew C.
AU - Benassi, null
AU - Seller, Paul
AU - Bettelli, null
AU - Zappettini, null
AU - Zambelli, null
PY - 2017
Y1 - 2017
N2 - Photon counting arrays with energy resolving capabilities are recently desired for the next-generation X-ray imaging systems. In this work, we present the performance of a 2 mm thick CZT pixel detector, with pixel pitches of 500 μm and 250 μm, coupled to a fast and low noise ASIC (PIXIE ASIC), characterized by only the preamplifier stage. A 16-channel digital readout electronics was used to continuously digitize and process each output channel from the PIXIE ASIC, performing multi-parameter analysis (event arrival time, pulse shape, pulse height) at low and high input counting rates (ICRs). The spectroscopic response of the system to monochromatic X-ray and gamma ray sources, at both low and high ICRs, is presented with particular attention to the mitigation of some typical spectral distortions (pile-up and charge sharing). The detector allows good energy resolution at moderate cooling (3% FWHM 59.5 keV, -1200 V, T = 5 C) by using fast shaped pulses (i.e. pulses with time widths of 300 ns). Charge sharing investigations were performed by using a fine time coincidence analysis (TCA) and a pulse shape analysis (PSA). The potentialities of the PSA for charge sharing detection even at high photon counting rates were also shown.
AB - Photon counting arrays with energy resolving capabilities are recently desired for the next-generation X-ray imaging systems. In this work, we present the performance of a 2 mm thick CZT pixel detector, with pixel pitches of 500 μm and 250 μm, coupled to a fast and low noise ASIC (PIXIE ASIC), characterized by only the preamplifier stage. A 16-channel digital readout electronics was used to continuously digitize and process each output channel from the PIXIE ASIC, performing multi-parameter analysis (event arrival time, pulse shape, pulse height) at low and high input counting rates (ICRs). The spectroscopic response of the system to monochromatic X-ray and gamma ray sources, at both low and high ICRs, is presented with particular attention to the mitigation of some typical spectral distortions (pile-up and charge sharing). The detector allows good energy resolution at moderate cooling (3% FWHM 59.5 keV, -1200 V, T = 5 C) by using fast shaped pulses (i.e. pulses with time widths of 300 ns). Charge sharing investigations were performed by using a fine time coincidence analysis (TCA) and a pulse shape analysis (PSA). The potentialities of the PSA for charge sharing detection even at high photon counting rates were also shown.
KW - Nuclear Medicine and Imaging; Instrumentation; Nuclear and High Energy Physics; Electronic
KW - Optical and Magnetic Materials
KW - Radiology
KW - Nuclear Medicine and Imaging; Instrumentation; Nuclear and High Energy Physics; Electronic
KW - Optical and Magnetic Materials
KW - Radiology
UR - http://hdl.handle.net/10447/271787
M3 - Other
SP - 1
EP - 7
ER -