Search results for "High photon counting rate"
showing 6 items of 6 documents
Digital performance improvements of a CdTe pixel detector for high flux energy-resolved X-ray imaging
2015
Abstract Photon counting detectors with energy resolving capabilities are desired for high flux X-ray imaging. In this work, we present the performance of a pixelated Schottky Al/p-CdTe/Pt detector (4×4) coupled to a custom-designed digital readout electronics for high flux measurements. The detector (4×4×2 mm 3 ) has an anode layout based on an array of 16 pixels with a geometric pitch of 1 mm (pixel size of 0.6 mm). The 4-channel readout electronics is able to continuously digitize and process the signals from each pixel, performing multi-parameter analysis (event arrival time, pulse shape, pulse height, pulse time width, etc.) even at high fluxes and at different throughput and energy re…
Direct Measurement of Mammographic X-Ray Spectra with a Digital CdTe Detection System
2012
In this work we present a detection system, based on a CdTe detector and an innovative digital pulse processing (DPP) system, for high-rate X-ray spectroscopy in mammography (1–30 keV). The DPP system performs a height and shape analysis of the detector pulses, sampled and digitized by a 14-bit, 100 MHz ADC. We show the results of the characterization of the detection system both at low and high photon counting rates by using monoenergetic X-ray sources and a nonclinical X-ray tube. The detection system exhibits excellent performance up to 830 kcps with an energy resolution of 4.5% FWHM at 22.1 keV. Direct measurements of clinical molybdenum X-ray spectra were carried out by using a pinhole…
Experimental results from Al/p-CdTe/Pt X-ray detectors
2013
Recently, Al/CdTe/Pt detectors have been proposed for the development of high resolution X-ray spectrometers. Due to the low leakage currents, these detectors allow high electric fields and the pixellization of anodes with the possibility to realize single charge carrier sensing detectors. In this work, we report on the results of electrical and spectroscopic investigations on CdTe diode detectors with Al/CdTe/Pt electrode configuration (4.1×4.1×0.75 and 4.1×4.1×2 mm3). The detectors are characterized by very low leakage currents in the reverse bias operation: 0.3 nA at 25 °C and 2.4 pA at -25 °C under a bias voltage of -1000 V. The spectroscopic performance of the detectors at both low and…
High-rate x-ray spectroscopy in mammography with a CdTe detector: A digital pulse processing approach
2010
Purpose:Direct measurement of mammographic x-ray spectra under clinical conditions is a difficult task due to the high fluence rate of the x-ray beams as well as the limits in the development of high resolution detection systems in a high counting rate environment. In this work we present a detection system, based on a CdTe detector and an innovative digital pulse processing (DPP) system, for high-rate x-ray spectroscopy in mammography. Methods: The DPP system performs a digital pile-up inspection and a digital pulse height analysis of the detector signals, digitized through a 14-bit, 100 MHz digitizer, for x-ray spectroscopy even at high photon counting rates. We investigated on the respon…
Real time digital pulse processing for X-ray and gamma ray semiconductor detectors
2013
Abstract Digital pulse processing (DPP) systems, based on direct digitizing and processing of detector signals, have recently been favoured over analog electronics, ensuring higher flexibility, stability, lower dead time and better spectroscopic performance. In this work, we present the performance of a new real time DPP system for X-ray and gamma ray semiconductor detectors. The system is based on a commercial digitizer equipped with a custom DPP firmware, developed by our group, for on-line pulse height and shape analysis. X-ray and gamma ray spectra measurements with cadmium telluride (CdTe) and germanium (Ge) detectors highlight the excellent performance of the system both at low and hi…
Digital techniques for high-rate high-resolution radiation measurements
2014
Digital pulse processing (DPP) techniques are increasingly used in the development of modern spectroscopic systems. DPP systems, based on direct digitizing and processing of detector signals (preamplifier output signals), ensure higher flexibility, stability, lower dead time, higher throughput and better energy resolution than traditional pulse processing systems. In this work, we present our progress in the development of DPP systems for high-rate high-resolution radiation measurements. An innovative digital system, able to perform multi-parameter analysis (input counting rate, pulse height, pulse shape, event arrival time, etc.) even at high photon counting rates is presented. Experimenta…