![]() Low dose (809 ± 6 Gy) and high dose (6230 ± 20 Gy) experiments were performed at a Medipix3RX single chip detector, bonded to a 200 □m thick silicon chip. Thus, it was possible to verify their correlation and support the feasibility of using the deposited dose obtained via Monte Carlo simulation as an estimation of the deposited dose value. This correction enabled a comparison between the experimentally obtained image and detected spectrum with the ones resulting from the Monte Carlo simulation. The effects of charge dispersion in the sensor, which are relevant in pixelated detectors, were implemented in the code. This parameter was chosen once there is a consensus in the literature that the phenomena related to damage in the considered energy range of 2 to 100 keV corresponds to dose deposition in these layers. The dose values in the oxide layers of the CMOS transistors were obtained through Monte Carlo simulation, based on the PENELOPE code. This work aimed to understand the phenomena behind the effect of radiation on image data, recognize patterns among the possible effects and quantitatively relate the deposited dose with damages in the data provided by the detector, seeking to establish limits for a data quality assurance for the various applications, as well as the frequency of possible maintenance procedures to ensure the best performance of the detector. In the case of the modern synchrotron applications, this radiation tends to high intensities, compromising the detector’s Higher energies and smaller efficiency, can be partially transmitted by the sensor, reaching the reading electronics of each pixel, which is located behind it. The radiation incident on the sensor, in the case of In both applications, detector failures can result in severe data loss. Hybrid pixel detectors are being consolidated as one of the best approaches for X-ray imaging techniques, addressing synchrotron and medical applications. As a possible consequence, the model can be used to predict precisely the behavior of photon counting detection systems as a function of the design parameters. The actual contributions of the charge sharing and of the electronic noise are identified and estimated. The fitting performances of the model has been assessed on a set of experimental integral pulse height spectra measured with an IBEX photon counting ASIC bonded to a 450μm thick Silicon sensor with 75μm×75μm pixel size, irradiated with monochromatic X-rays in the energy range 6–12.4 keV, with excellent agreement between model and measurement. The equations describing the pixel point spread function and the integral pulse height spectrum are derived preserving the genuine 2D nature of the charge collection process. It is based only on geometrical and physical parameters such as the pixel size, the charge cloud size at the pixel depth and the total electronic noise of the front-end circuitry. We present a simple fitting model for the pixel response to monochromatic X-rays in single photon counting pixelated detectors that takes into account the 2D effects of the charge sharing and of the electronic noise on the photon counting process. (NNPS) and by assessing the Noise Equivalent number of Quanta (NEQ). We characterize the imaging performance for different combinations of acquisition modes and thresholdsīy measuring the presampling Modulation Transfer Function (MTF), the Normalized Noise Power Spectrum Measured energy resolution of the three acquisition modes for different energies are here reported. Modes: a pure photon counting mode and two modes specially designed to correct charge-sharing effects. The Pixie-III readout system includes programmable energy thresholds and it implements three acquisition Pixirad-1/Pixie-III device, a XPCD carrying a 650 □□ thick CdTe sensor with a small pixel (62 × 62 □□2). In this paper we present the results of the characterization of the Multiple counts can be removedīy acting on the discriminator threshold or they can be corrected by means of specific acquisition modalities Not only the energy resolution, but it also worsens the spatial resolution. ![]() X-ray Photon Counting Detectors (XPCDs) with thick semiconductor sensors and small pixel sizes suffer from aĬharge-sharing effect which can induce multiple counts from a single interacting photon.
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