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Title: Characterising the large coherence length at diamond’s beamline I13L

Abstract

I13 is a 250 m long hard x-ray beamline (6 keV to 35 keV) at the Diamond Light Source. The beamline comprises of two independent experimental endstations: one for imaging in direct space using x-ray microscopy and one for imaging in reciprocal space using coherent diffraction based imaging techniques [1]. An outstanding feature of the coherence branch, due to its length and a new generation of ultra-stable beamline instrumentation [2], is its capability of delivering a very large coherence length well beyond 200 μm, providing opportunities for unique x-ray optical experiments. In this paper we discuss the challenges of measuring a large coherence length and present quantitative measurement based on analyzing diffraction patterns from a boron fiber [3]. We also discuss the limitations of this classical method in respect to detector performance, very short and long coherence lengths. Furthermore we demonstrate how a Ronchi grating setup [4] can be used to quickly establish if the beam is coherent over a large area.

Authors:
;  [1]; ;  [2];  [1];  [3]
  1. Diamond Light Source Ltd, Didcot, UK, OX11 0DE (United Kingdom)
  2. KTH Royal Institute of Technology, Stockholm, Sweden, SE-100 44 (Sweden)
  3. (United States)
Publication Date:
OSTI Identifier:
22608446
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 1741; Journal Issue: 1; Conference: SRI2015: 12. international conference on synchrotron radiation instrumentation, New York, NY (United States), 6-10 Jul 2015; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; BEAMS; BORON; COHERENCE LENGTH; DIAMONDS; DIFFRACTION; FIBERS; HARD X RADIATION; KEV RANGE; MICROSCOPY; PERFORMANCE

Citation Formats

Wagner, U. H., E-mail: ulrich.wagner@diamond.ac.uk, Parsons, A., Rahomaki, J., Vogt, U., Rau, C., and Northwestern University, Chicago, IL 60611-3008. Characterising the large coherence length at diamond’s beamline I13L. United States: N. p., 2016. Web. doi:10.1063/1.4952942.
Wagner, U. H., E-mail: ulrich.wagner@diamond.ac.uk, Parsons, A., Rahomaki, J., Vogt, U., Rau, C., & Northwestern University, Chicago, IL 60611-3008. Characterising the large coherence length at diamond’s beamline I13L. United States. doi:10.1063/1.4952942.
Wagner, U. H., E-mail: ulrich.wagner@diamond.ac.uk, Parsons, A., Rahomaki, J., Vogt, U., Rau, C., and Northwestern University, Chicago, IL 60611-3008. 2016. "Characterising the large coherence length at diamond’s beamline I13L". United States. doi:10.1063/1.4952942.
@article{osti_22608446,
title = {Characterising the large coherence length at diamond’s beamline I13L},
author = {Wagner, U. H., E-mail: ulrich.wagner@diamond.ac.uk and Parsons, A. and Rahomaki, J. and Vogt, U. and Rau, C. and Northwestern University, Chicago, IL 60611-3008},
abstractNote = {I13 is a 250 m long hard x-ray beamline (6 keV to 35 keV) at the Diamond Light Source. The beamline comprises of two independent experimental endstations: one for imaging in direct space using x-ray microscopy and one for imaging in reciprocal space using coherent diffraction based imaging techniques [1]. An outstanding feature of the coherence branch, due to its length and a new generation of ultra-stable beamline instrumentation [2], is its capability of delivering a very large coherence length well beyond 200 μm, providing opportunities for unique x-ray optical experiments. In this paper we discuss the challenges of measuring a large coherence length and present quantitative measurement based on analyzing diffraction patterns from a boron fiber [3]. We also discuss the limitations of this classical method in respect to detector performance, very short and long coherence lengths. Furthermore we demonstrate how a Ronchi grating setup [4] can be used to quickly establish if the beam is coherent over a large area.},
doi = {10.1063/1.4952942},
journal = {AIP Conference Proceedings},
number = 1,
volume = 1741,
place = {United States},
year = 2016,
month = 7
}
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