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Title: Time-resolved ion imaging at free-electron lasers using TimepixCam

In this paper, the application of a novel fast optical-imaging camera, TimepixCam, to molecular photoionization experiments using the velocity-map imaging technique at a free-electron laser is described. TimepixCam is a 256 × 256 pixel CMOS camera that is able to detect and time-stamp ion hits with 20 ns timing resolution, thus making it possible to record ion momentum images for all fragment ions simultaneously and avoiding the need to gate the detector on a single fragment. This allows the recording of significantly more data within a given amount of beam time and is particularly useful for pump–probe experiments, where drifts, for example, in the timing and pulse energy of the free-electron laser, severely limit the comparability of pump–probe scans for different fragments taken consecutively. Finally, in principle, this also allows ion–ion covariance or coincidence techniques to be applied to determine angular correlations between fragments.
 [1] ;  [2] ;  [3] ;  [4] ;  [4] ;  [4] ;  [5] ;  [6] ;  [3]
  1. Brookhaven National Lab. (BNL), Upton, NY (United States); Princeton Univ., NJ (United States)
  2. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany); European X-ray Free-Electron Laser (XFEL), Hamburg (Germany)
  3. Kansas State Univ., Manhattan, KS (United States). J. R. Macdonald Lab. Dept. of Physics
  4. Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
  5. CNRS Lab. of Physical Chemistry - Matter and Radiation (LCPMR), Paris (France)
  6. Brookhaven National Lab. (BNL), Upton, NY (United States)
Publication Date:
Report Number(s):
Journal ID: ISSN 1600-5775
Grant/Contract Number:
SC0012704; FG02-86ER13491
Accepted Manuscript
Journal Name:
Journal of Synchrotron Radiation (Online)
Additional Journal Information:
Journal Name: Journal of Synchrotron Radiation (Online); Journal Volume: 25; Journal Issue: 2; Journal ID: ISSN 1600-5775
International Union of Crystallography
Research Org:
Kansas State Univ., Manhattan, KS (United States); Brookhaven National Lab. (BNL), Upton, NY (United States); Deutsches Elektronen-Synchrotron (DESY), Hamburg (Germany)
Sponsoring Org:
USDOE Office of Science (SC), Basic Energy Sciences (BES) (SC-22); BNL Laboratory Directed Research and Development (LDRD) Program; Helmholtz Association of German Research Centres
Country of Publication:
United States
47 OTHER INSTRUMENTATION; 71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSICS; time-stamping camera; velocity map imaging; VMI; free-electron laser; FEL; ultrafast laser; pump-probe experiments; mass spectrometry
OSTI Identifier: