Energy-dispersive Laue diffraction by means of a frame-store pnCCD

Abstract

A frame‐store pn‐junction CCD detector was applied to the energy‐dispersive X‐ray Laue diffraction study of a γ‐LiAlO2 crystal with white synchrotron radiation. Exploiting the simultaneous spatial and energy resolution of the detector the crystallographic unit cell of γ‐LiAlO2 could be determined without any a priori information about the sample. The potential for application in X‐ray structure analysis is tested by comparing experimental structure factors taken under a single exposure with those calculated from the known crystal structure. After correcting the measured spot intensities by angular and energy‐dependent parameters, the agreement between experimental and theoretical kinematical structure factors is better than 10%.

Fast GPU-based absolute intensity determination for energy-dispersive X-ray Laue diffraction

“…Every observed peak is an integer multiple of the base energy (see section 3.3). 4. Spot spectrum and background spectrum are extracted.…”

“…The possibility of unit-cell calculation without additional information and the need for sample rotation is a clear advantage of the Laue method compared to monochromatic applications. Moreover, absolute intensity determination allows to extract kinematical structure-factor moduli of individual position-and energy-resolved Bragg peaks of the crystal from the pnCCD-generated data sets with adequate accuracy [4]. Recently, energydispersive Laue diffraction with a pnCCD was considered in the ultra-hard X-ray regime between 40 keV and 140 keV providing a sufficiently large Laue spot density to investigate inorganic crystals in one single measurement [5].…”

Local strain redistribution in a coarse-grained nickel-based superalloy subjected to shot-peening, fatigue or thermal exposure investigated using synchrotron X-ray Laue microdiffraction

“…Three methods were developed for that purpose: switching from polychromatic mode to tunable-energy monochromatic beam mode [37], using 1D or 2D energy dispersive detectors [31,38] and a crystal filter [39] while remaining in the polychromatic mode. In this study, an energy dispersive point detector was used (see Fig.…”

Energy-dispersive in-house Laue diffraction experiments with a Pilatus detector

“…The use of position sensitive detectors with capability of energy resolution measurements (e.g. hybrid pixel Pilatus detector [2], frame store pnCCD [3] etc.) allows overcoming such problems as the energy-dispersive analysis of Bragg peaks enables a unique determination of the lattice and resolution of higher harmonics without any a priory information [3].…”

“…hybrid pixel Pilatus detector [2], frame store pnCCD [3] etc.) allows overcoming such problems as the energy-dispersive analysis of Bragg peaks enables a unique determination of the lattice and resolution of higher harmonics without any a priory information [3]. Energy-dispersive Laue diffraction (EDLD) experiments are usually done at synchrotron sources with high intense x-ray irradiation.…”