Abstract
The nanometer length-scale holds precious information on several dynamical processes that develop from picoseconds to seconds. In the past decades, X-ray scattering techniques have been developed to probe the dynamics at such length-scales on either ultrafast (sub-nanosecond) or slow ((milli-)second) time scales. With the start of operation of the European XFEL, thanks to the MHz repetition rate of its X-ray pulses, even the intermediate μs range have become accessible. Measuring dynamics on such fast timescales requires the development of new technologies such as the Adaptive Gain Integrating Pixel Detector (AGIPD). μs-XPCS is a promising technique to answer many scientific questions regarding microscopic structural dynamics, especially for soft condensed matter systems. However, obtaining reliable results with complex detectors at free-electron laser facilities is challenging and requires more sophisticated analysis methods compared to experiments at storage rings. Here, we discuss challenges and possible solutions to perform XPCS experiments with the AGIPD at European XFEL; in particular, at the Materials Imaging and Dynamics (MID) instrument. We present our data analysis pipeline and benchmark the results obtained at the MID instrument with a well-known sample composed by silica nanoparticles dispersed in water.
Highlights
Free-electron laser facilities in the hard X-ray regime (XFELs) bear the potential for studying molecular dynamics utilizing time-domain methods such as X-ray photon correlation spectroscopy (XPCS) and the related technique X-ray speckle visibility spectroscopy (XSVS)
We explain the steps of our XPCS data analysis pipeline in detail starting with the data calibration
XPCS experiments typically deal with relatively low intensity signals, since the speckle patters produced by amorphous systems are several orders of magnitude less intense than the Bragg reflections produced bycrystalline samples
Summary
Free-electron laser facilities in the hard X-ray regime (XFELs) bear the potential for studying molecular dynamics utilizing time-domain methods such as X-ray photon correlation spectroscopy (XPCS) and the related technique X-ray speckle visibility spectroscopy (XSVS). Both techniques are based on coherent X-rays and enable probing dynamics between femtoseconds and several hours. These techniques have been developed at synchrotron radiation sources since the 1990s [1,2,3,4]. The intensity fluctuations of the speckles reflect the change of the spatial arrangement of the sample where the length scale is selected by choosing a particular momentum transfer q
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
