Author: Flechsig, U.
Paper Title Page
Grating Interferometry Applied to X-ray Wavefront Metrology at the SACLA  
  • Y. Kayser, Ch. David, U. Flechsig, S. Rutishauser
    PSI, Villigen PSI, Switzerland
  • T.K. Kameshima, T. Katayama
    JASRI/SPring-8, Hyogo, Japan
  • H. Ohashi
    Japan Synchrotron Radiation Research Institute (JASRI/SPring-8), Hyogo, Japan
  • M. Yabashi
    RIKEN SPring-8 Center, Sayo-cho, Sayo-gun, Hyogo, Japan
  Grating interferometry allows for spatially resolved studies of the local wavefront propagation direction with an angular sensitivity of tens of nanoradian. In this perspective the grating interferometry technique has found application in the metrology of X-ray optics at synchrotron facilities and was moreover used for the investigation of the X-ray wavefront properties at the LCLS(*). At the SACLA grating interferometry was applied to two different types of experiments. A first application was the study the wavefront preservation capabilities of the X-ray optics installed upstream of the end station of beam line 3 (two off-set mirror systems and a double crystal monochromator). The experimental results confirmed the excellent quality of the optical components and demonstrated the sensitivity of grating interferometry. In a second application the source point position was determined as the XFEL was driven into saturation. Grating interferometry permits, thus, to get a better understanding of the XFEL machine.
(*) S. Rutishauser, L. Samoylova, J. Krzywinski, et al., “Exploring the wavefront of hard X-ray free-electron laser radiation,” Nat. Commun. 3, 947 (2012).
Soft X-ray Self-seeding Setup and Results at LCLS  
  • D.F. Ratner, J.W. Amann, D.K. Bohler, M. Boyes, D. Cocco, F.-J. Decker, Y. Ding, D. Fairley, Y. Feng, J.B. Hastings, P.A. Heimann, Z. Huang, J. Krzywinski, H. Loos, A.A. Lutman, G. Marcus, A. Marinelli, T.J. Maxwell, S.P. Moeller, P.A. Montanez, D.S. Morton, H.-D. Nuhn, D.R. Walz, J.J. Welch, J. Wu
    SLAC, Menlo Park, California, USA
  • K. Chow, L.N. Rodes
    LBNL, Berkeley, California, USA
  • U. Flechsig
    PSI, Villigen PSI, Switzerland
  • S. Serkez
    DESY, Hamburg, Germany
  The soft X-ray self seeding program was designed to provide near transform-limited pulses in the range of 500 eV to 1000 eV. The project was a three-way collaboration between SLAC, Lawrence Berkeley National Lab, and the Paul Scherrer Institute in Switzerland. Installation finished in the Fall of 2013, and after the early stages of commissioning we have measured up to 0.5mJ pulse energy and resolving powers of up to 5000 across the design wavelength range, representing a several-fold increase in the brightness compared to the normal LCLS operating mode. Future work will aim to increase the total pulse energy and establish self-seeding as a robust user operation mode.  
slides icon Slides TUC02 [10.464 MB]