WE-G-204-03: Photon-Counting Hexagonal Pixel Array CdTe Detector: Optimal Resampling to Square Pixels

Using X-ray energies higher than those normally used (5–15 keV) for macromolecular X-ray crystallography (MX) at synchrotron sources can theoretically increase the achievable signal as a function of dose and reduce the rate of radiation damage. In practice, a major stumbling block to the use of higher X-ray energy has been the reduced quantum efficiency of silicon detectors as the X-ray energy increases, but hybrid photon-counting CdTe detectors are optimized for higher X-ray energies, and their performance has been steadily improving. Here the potential advantages of using higher incident beam energy together with a CdTe detector for MX are explored, with a particular focus on the advantages that higher beam energies may have for MX experiments with microbeams or microcrystals. Monte Carlo simulations are presented here which for the first time include the efficiency responses of some available X-ray detectors, as well as the possible escape of photoelectrons from the sample and their entry from surrounding material. The results reveal a `sweet spot' at an incident X-ray energy of 26 keV, and show a greater than factor of two improvement in diffraction efficiency at this energy when using microbeams and microcrystals of 5 µm or less.

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Photon counting readout pixel array in 0.18-μm CMOS technology for on-line gamma-ray imaging of103palladium seeds for permanent breast seed implant (PBSI) brachytherapy

10.1117/12.770766 ◽

2008 ◽

Cited By ~ 1

Author(s):

A. H. Goldan ◽

K. S. Karim ◽

A. Reznik ◽

C. B. Caldwell ◽

J. A. Rowlands

Keyword(s):

Gamma Ray ◽

Photon Counting ◽

Cmos Technology ◽

Pixel Array ◽

Gamma Ray Imaging ◽

On Line

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Linear fitting of multi-threshold counting data with a pixel-array detector for spectral X-ray imaging

Journal of Synchrotron Radiation ◽

10.1107/s1600577514014167 ◽

2014 ◽

Vol 21 (5) ◽

pp. 1180-1187 ◽

Cited By ~ 1

Author(s):

Ryan D. Muir ◽

Nicholas R. Pogranichney ◽

J. Lewis Muir ◽

Shane Z. Sullivan ◽

Kevin P. Battaile ◽

...

Keyword(s):

Photon Counting ◽

Array Detector ◽

X Ray ◽

Spectral Fitting ◽

Counting Data ◽

X Ray Imaging ◽

Pixel Array ◽

Multi Wavelength ◽

Pixel Array Detector ◽

Corner Effects

Experiments and modeling are described to perform spectral fitting of multi-threshold counting measurements on a pixel-array detector. An analytical model was developed for describing the probability density function of detected voltage in X-ray photon-counting arrays, utilizing fractional photon counting to account for edge/corner effects from voltage plumes that spread across multiple pixels. Each pixel was mathematically calibrated by fitting the detected voltage distributions to the model at both 13.5 keV and 15.0 keV X-ray energies. The model and established pixel responses were then exploited to statistically recover images of X-ray intensity as a function of X-ray energy in a simulated multi-wavelength and multi-counting threshold experiment.

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The CirPAD, a circular 1.4 M hybrid pixel detector dedicated to X-ray diffraction measurements at Synchrotron SOLEIL

Journal of Synchrotron Radiation ◽

10.1107/s1600577521012492 ◽

2022 ◽

Vol 29 (1) ◽

Author(s):

Kewin Desjardins ◽

Cristian Mocuta ◽

Arkadiusz Dawiec ◽

Solenn Réguer ◽

Philippe Joly ◽

...

Keyword(s):

Reference Sample ◽

Photon Counting ◽

Array Detector ◽

Pixel Detector ◽

X Ray Diffraction ◽

High Count ◽

X Ray ◽

Pixel Array ◽

Diffraction Imaging ◽

Pixel Array Detector

One of the challenges of all synchrotron facilities is to offer the highest performance detectors for all their specific experiments, in particular for X-ray diffraction imaging and its high throughput data collection. In that context, the DiffAbs beamline, the Detectors and the Design and Engineering groups at Synchrotron SOLEIL, in collaboration with ImXPAD and Cegitek companies, have developed an original and unique detector with a circular shape. This detector is based on the hybrid pixel photon-counting technology and consists of the specific assembly of 20 hybrid pixel array detector (XPAD) modules. This article aims to demonstrate the main characteristics of the CirPAD (for Circular Pixel Array Detector) and its performance – i.e. excellent pixel quality, flat-field correction, high-count-rate performance, etc. Additionally, the powder X-ray diffraction pattern of an LaB6 reference sample is presented and refined. The obtained results demonstrate the high quality of the data recorded from the CirPAD, which allows the proposal of its use to all scientific communities interested in performing experiments at the DiffAbs beamline.

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