Disentangling detector data in XFEL studies of temporally resolved solution state chemistry

Tim Brandt van Driel, Kasper Skov Kjær, Elisa Biasin, Kristoffer Haldrup, Henrik Till Lemke, Martin Meedom Nielsen

Research output: Contribution to journalJournal articleResearchpeer-review

Abstract

With the arrival of X-ray Free Electron Lasers (XFELs), 2D area detectors with a large dynamic range for detection of hard X-rays with fast readout rates are required for many types of experiments. Extracting the desired information from these detectors has been challenging due to unpredicted fluctuations in the measured images. For techniques such as time-resolved X-ray Diffuse Scattering (XDS), small differences in signal intensity are the starting point for analysis. Fluctuations in the total detected signal remain in the differences under investigation, obfuscating the signal. To correct such artefacts, Singular Value Decomposition (SVD) can be used to identify and characterize the observed detector fluctuations and assist in assigning some of them to variations in physical parameters such as X-ray energy and X-ray intensity. This paper presents a methodology for robustly identifying, separating and correcting fluctuations on area detectors based on XFEL beam characteristics, to enable the study of temporally resolved solution state chemistry on the femtosecond timescale.
Original languageEnglish
JournalFaraday Discussions
Volume177
Pages (from-to)443-465
Number of pages23
ISSN1359-6640
DOIs
Publication statusPublished - 2015

Keywords

  • CHEMISTRY,
  • X-RAY-SCATTERING
  • FREE-ELECTRON LASER
  • SINGULAR-VALUE DECOMPOSITION
  • EXCITED-STATE
  • SPECTROSCOPY
  • DYNAMICS
  • TRACKING

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