Energy resolution of the CdTe-XPAD detector: calibration and potential for Laue diffraction measurements on protein crystals

Abstract

The XPAD3S-CdTe, a CdTe photon-counting pixel array detector, has been used to measure the energy and the intensity of the white-beam diffraction from a lysozyme crystal. A method was developed to calibrate the detector in terms of energy, allowing incident photon energy measurement to high resolution (approximately 140 eV), opening up new possibilities in energy-resolved X-ray diffraction. In order to demonstrate this, Laue diffraction experiments were performed on the bending-magnet beamline METROLOGIE at Synchrotron SOLEIL. The X-ray energy spectra of diffracted spots were deduced from the indexed Laue patterns collected with an imaging-plate detector and then measured with both the XPAD3S-CdTe and the XPAD3S-Si, a silicon photon-counting pixel array detector. The predicted and measured energy of selected diffraction spots are in good agreement, demonstrating the reliability of the calibration method. These results open up the way to direct unit-cell parameter determination and the measurement of high-quality Laue data even at low resolution. Based on the success of these measurements, potential applications in X-ray diffraction opened up by this type of technology are discussed.

Tomography and imaging at the PSICHE beam line of the SOLEIL synchrotron

“…The tomography rotation axis can be used to select the orientation of the scattering vector, or can be oscillated to sample a larger selection of grains, depending on the sample and the requirements of the measurement. Furthermore the white beam allows Laue diffraction approaches to be used (Medjoubi et al, 2012).…”

Detective quantum efficiency model of single-X-ray-photon counting hybrid pixel detectors

“…Consequently, 1-k is the probability for an X-ray to deposit fully its Gaussian-distributed energy in one pixel. Therefore, under these approximations, the expression of the energy deposition spectrum simplifies into the model proposed by Ponchut [11,20].…”

Fast pole figure acquisition using area detectors at the DiffAbs beamline – Synchrotron SOLEIL

“…The development of large area X-ray detectors with high sensitivity, large dynamic range, low noise and fast response makes possible this kind of measurement at synchrotron facilities (Brö nnimann et al, 2003;Ponchut et al, 2005Ponchut et al, , 2007Ejdrup et al, 2009;Henrich et al, 2009;Basolo et al, 2007;Rossi et al, 1999;Delpierre et al, 2007). The X-ray pixel area detector (XPAD) (Delpierre et al, 2007;Medjoubi et al, 2010Medjoubi et al, , 2012Fertey et al, 2013, and references therein) used for this study has a 500 mm-thick Si sensor and is composed of eight modules (each of them of size 15.6 Â 72.8 mm, pixelated silicon sensor); it is shown schematically in Fig. 2.…”