Experimental characterization of X-ray transverse coherence in the presence of beam transport optics

Research output: Contribution to journalJournal articleResearchpeer-review

  • O. Chubar
  • A. Fluerasu
  • Y.S. Chu
  • L. Berman
  • L. Wiegart
  • W.-K. Lee
  • J. Baltser
A simple Boron fiber based interference scheme [1] and other similar schemes are currently routinely used for X-ray coherence estimation at 3rd generation synchrotron radiation sources. If such a scheme is applied after a perfect monochromator and without any focusing / transport optics in the optical path, the interpretation of the measured interference pattern is relatively straightforward and can be done in terms of the basic parameters of the source [2]. However, if the interference scheme is used after some focusing optics, e.g. close to the X-ray beam waist, the visibility of fringes can be significantly affected by the new shape of the focused beam phase-space. At the same time, optical element imperfections still have a negative impact on the transverse coherence. In such situations, which are frequently encountered in experiments at beamlines, the quantitative interpretation of a measured interference pattern is not straightforward. Here we show that this can nevertheless be done by using partially-coherent synchrotron radiation wavefront propagation simulations. The results obtained from measurements, performed at the 32-ID undulator beamline of the Advanced Photon Source, and wavefront propagation based simulations show, in particular, that new generation 1D Beryllium Compound Refractive Lenses [3, 4] do not reduce the X-ray transverse coherence in any significant manner.
Original languageEnglish
Article number052028
Book seriesJournal of Physics: Conference Series (Online)
Volume425
Issue numberPART 5
Number of pages5
ISSN1742-6596
DOIs
Publication statusPublished - 1 Jan 2013

ID: 45576441