skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: A sagittally focusing double-multilayer monochromator for ultrafast x-ray imaging applications.

Abstract

The development of a sagittally focusing double-multilayer monochromator is reported, which produces a spatially extended wide-bandpass X-ray beam from an intense synchrotron bending-magnet source at the Advanced Photon Source, for ultrafast X-ray radiography and tomography applications. This monochromator consists of two W/B4C multilayers with a 25 {angstrom} period coated on Si single-crystal substrates. The second multilayer is mounted on a sagittally focusing bender, which can dynamically change the bending radius of the multilayer in order to condense and focus the beam to various points along the beamline. With this new apparatus, it becomes possible to adjust the X-ray beam size to best match the area detector size and the object size to facilitate more efficient data collection using ultrafast X-ray radiography and tomography.

Authors:
; ; ; ; ; ; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC); EE
OSTI Identifier:
939312
Report Number(s):
ANL/XSD/JA-50874
Journal ID: ISSN 0909-0495; JSYRES; TRN: US0806746
DOE Contract Number:
DE-AC02-06CH11357
Resource Type:
Journal Article
Resource Relation:
Journal Name: J. Synchrotron Radiat.; Journal Volume: 14; Journal Issue: 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
43 PARTICLE ACCELERATORS; ADVANCED PHOTON SOURCE; BENDING; FOCUSING; MONOCHROMATORS; SUBSTRATES; SYNCHROTRONS; TOMOGRAPHY; X-RAY RADIOGRAPHY

Citation Formats

Wang, Y., Narayanan, S., Shu, D., Mashayekhi, A., Qian, J., Liu, J., Wang, J., and X-Ray Science Division. A sagittally focusing double-multilayer monochromator for ultrafast x-ray imaging applications.. United States: N. p., 2007. Web. doi:10.1107/S0909049506050205.
Wang, Y., Narayanan, S., Shu, D., Mashayekhi, A., Qian, J., Liu, J., Wang, J., & X-Ray Science Division. A sagittally focusing double-multilayer monochromator for ultrafast x-ray imaging applications.. United States. doi:10.1107/S0909049506050205.
Wang, Y., Narayanan, S., Shu, D., Mashayekhi, A., Qian, J., Liu, J., Wang, J., and X-Ray Science Division. Mon . "A sagittally focusing double-multilayer monochromator for ultrafast x-ray imaging applications.". United States. doi:10.1107/S0909049506050205.
@article{osti_939312,
title = {A sagittally focusing double-multilayer monochromator for ultrafast x-ray imaging applications.},
author = {Wang, Y. and Narayanan, S. and Shu, D. and Mashayekhi, A. and Qian, J. and Liu, J. and Wang, J. and X-Ray Science Division},
abstractNote = {The development of a sagittally focusing double-multilayer monochromator is reported, which produces a spatially extended wide-bandpass X-ray beam from an intense synchrotron bending-magnet source at the Advanced Photon Source, for ultrafast X-ray radiography and tomography applications. This monochromator consists of two W/B4C multilayers with a 25 {angstrom} period coated on Si single-crystal substrates. The second multilayer is mounted on a sagittally focusing bender, which can dynamically change the bending radius of the multilayer in order to condense and focus the beam to various points along the beamline. With this new apparatus, it becomes possible to adjust the X-ray beam size to best match the area detector size and the object size to facilitate more efficient data collection using ultrafast X-ray radiography and tomography.},
doi = {10.1107/S0909049506050205},
journal = {J. Synchrotron Radiat.},
number = 2007,
volume = 14,
place = {United States},
year = {Mon Jan 01 00:00:00 EST 2007},
month = {Mon Jan 01 00:00:00 EST 2007}
}
  • We report the development of a sagittally focusing double multilayer monochromator to produce a spatially extended, wide-bandpass x-ray beam from intense synchrotron bending-magnet source at the Advanced Photon Source for ultrafast x-radiography and -tomography applications. This monochromator consists of the two W/B4C multilayers with a 25-Aa periodicity coated on Si single-crystal substrates. The second crystal is mounted on a saggitally focusing bender which can; dynamically change the bending radius of the crystal in order to focus the beam to various points along the beamline. With this new apparatus, it becomes possible to adjust the x-ray beam size to best matchmore » the area detector size and the object size to facilitate a more efficient data collection using ultrafast x-radiography and -tomography.« less
  • We present a double multilayer monochromator (DMM) design which has been realized for the BAMline(BESSY-II light source, Germany) as well as in an updated version for the TopoTomo beamline (ANKA light source. Germany)[1-4]. The latter contains two pairs of multilayer stripes in order to avoid absorption edges of the coating material. For both DMMs, the second multilayer offers a meridional bending option for beam compression to increase the available photon flux density. Each multilayer mirror is equipped with a vertical stage for height adjustments allowing for compensation of varying incoming beam heights and giving a certain flexibility choosing the offset.more » The second multilayer can be moved in the beam direction in order to cover the full energy range available. Furthermore, a white beam option is available.« less
  • The X-11A beamline at the NSLS has been upgraded to include a dynamic sagittally focusing second crystal in the monochromator, currently operating in the range 5.5--11 keV. The monochromator maintains a constant focus at the sample by adjustment of the bent crystal radius during the XAFS scan. The monochromator accepts 3.3 mrad of horizontal radiation and a spot size of {similar to}1.5 mm{sup 2} is achieved at the sample. The sagittally focusing mechanism in the monochromator is described and the results are presented of intensity profiles, spatial stability, and energy resolution between the energy ranges 6 and 10 keV, wheremore » the system performs most favorably. Intensity gains over unfocused operation are substantial and XAFS studies of dilute fluorescence samples reveal the expected {ital S}/{ital N} improvements, without any introduction of additional noise from the bending process. The mechanism operates with close to 100% efficiency between the energy ranges 6 and 8 keV. Bending errors hinder the performance at higher energies and also preclude effective harmonic rejection, by piezocrystal detuning, over the entire energy range.« less
  • Establishment of the parallelism between two axes, that of x rays and that of the cylinder made by a bent crystal, is found to be important when a sagittally focusing double-crystal monochromator is used. Detectable increase of reflection width and decrease of output intensity is observed when the angle between the above two axes becomes only 0.1{degree}. With the help of rotation stages to adjust the axis of the cylinder, the focus smaller than 1 mm is obtained up to 11 keV at BL-6B of the Photon Factory and about 3 mm is established up to 28 keV at NE1more » of the Accumulation Ring.« less
  • In the production of x-ray microbeams a trade-off between flux and beam size must often be made, particularly when using a bending magnet synchrotron source since the radiation emitted in the horizontal direction is not collimated. To circumvent this problem we have combined the diffraction from a sagitally-bent crystal with the meridional focusing of a Kirkpatrick-Baez (KB) system composed of two reflective surfaces coated with a platinum layer (1st mirror, vertical deflection) and with a Ni/B4C multilayer (2nd mirror, horizontal deflection). The experiments were performed at the ESRF BM5 beamline, for which the most favorable arrangement consisted of illuminating amore » KB system located faraway from the source with a horizontally converging or diverging beam produced by a sagittally-bent crystal located closer to the source. The 1st mirror demagnified the vertical dimension of the source whilst the 2nd further decreased the beam in the horizontal direction. Several flux/ spot-size configurations were tested by changing the position of the image of the sagittal crystal. The best (preliminary) results gave a focus of 2.6 {mu}m (vertical) x 6.8 {mu}m (horizontal) and an irradiance gain of 2.6 104. These figures were limited by the aberrations of the sagittally-bent crystal.« less