Characterization of a bent Laue double-crystal beam-expanding monochromator
Abstract
A bent Laue double-crystal monochromator system has been designed for vertically expanding the X-ray beam at the Canadian Light Source's BioMedical Imaging and Therapy beamlines. Expansion by a factor of 12 has been achieved without deteriorating the transverse coherence of the beam, allowing phase-based imaging techniques to be performed with high flux and a large field of view. However, preliminary studies revealed a lack of uniformity in the beam, presumed to be caused by imperfect bending of the silicon crystal wafers used in the system. Results from finite-element analysis of the system predicted that the second crystal would be most severely affected and has been shown experimentally. It has been determined that the majority of the distortion occurs in the second crystal and is likely caused by an imperfection in the surface of the bending frame. Here, measurements were then taken to characterize the bending of the crystal using both mechanical and diffraction techniques. In particular, two techniques commonly used to map dislocations in crystal structures have been adapted to map local curvature of the bent crystals. One of these, a variation of Berg–Berrett topography, has been used to quantify the diffraction effects caused by the distortion of the crystalmore »
- Authors:
-
- Univ. of Saskatchewan, Saskatoon, SK (Canada). Physics and Engineering Physics
- Argonne National Lab. (ANL), Argonne, IL (United States). X-ray Science Division
- Canadian Light Sources, Inc., Saskatoon, SK (Canada)
- Publication Date:
- Research Org.:
- Argonne National Lab. (ANL), Argonne, IL (United States)
- Sponsoring Org.:
- USDOE Office of Science (SC); Natural Sciences and Engineering Research Council of Canada (NSERC); Canadian Institutes of Health Research (CIHR); Canada Foundation for Innovation; Government of Saskatchewan; Western Economic Diversification Canada
- OSTI Identifier:
- 1425211
- Grant/Contract Number:
- AC02-06CH11357
- Resource Type:
- Accepted Manuscript
- Journal Name:
- Journal of Synchrotron Radiation (Online)
- Additional Journal Information:
- Journal Name: Journal of Synchrotron Radiation (Online); Journal Volume: 24; Journal Issue: 6; Journal ID: ISSN 1600-5775
- Publisher:
- International Union of Crystallography
- Country of Publication:
- United States
- Language:
- English
- Subject:
- 72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; Lang topography; Berg-Barrett topography; beam expander; double bent Laue monochromator; finite element analysis; finite-element analysis
Citation Formats
Martinson, Mercedes, Samadi, Nazanin, Shi, Xianbo, Liu, Zunping, Assoufid, Lahsen, and Chapman, Dean. Characterization of a bent Laue double-crystal beam-expanding monochromator. United States: N. p., 2017.
Web. doi:10.1107/S1600577517014059.
Martinson, Mercedes, Samadi, Nazanin, Shi, Xianbo, Liu, Zunping, Assoufid, Lahsen, & Chapman, Dean. Characterization of a bent Laue double-crystal beam-expanding monochromator. United States. https://doi.org/10.1107/S1600577517014059
Martinson, Mercedes, Samadi, Nazanin, Shi, Xianbo, Liu, Zunping, Assoufid, Lahsen, and Chapman, Dean. Thu .
"Characterization of a bent Laue double-crystal beam-expanding monochromator". United States. https://doi.org/10.1107/S1600577517014059. https://www.osti.gov/servlets/purl/1425211.
@article{osti_1425211,
title = {Characterization of a bent Laue double-crystal beam-expanding monochromator},
author = {Martinson, Mercedes and Samadi, Nazanin and Shi, Xianbo and Liu, Zunping and Assoufid, Lahsen and Chapman, Dean},
abstractNote = {A bent Laue double-crystal monochromator system has been designed for vertically expanding the X-ray beam at the Canadian Light Source's BioMedical Imaging and Therapy beamlines. Expansion by a factor of 12 has been achieved without deteriorating the transverse coherence of the beam, allowing phase-based imaging techniques to be performed with high flux and a large field of view. However, preliminary studies revealed a lack of uniformity in the beam, presumed to be caused by imperfect bending of the silicon crystal wafers used in the system. Results from finite-element analysis of the system predicted that the second crystal would be most severely affected and has been shown experimentally. It has been determined that the majority of the distortion occurs in the second crystal and is likely caused by an imperfection in the surface of the bending frame. Here, measurements were then taken to characterize the bending of the crystal using both mechanical and diffraction techniques. In particular, two techniques commonly used to map dislocations in crystal structures have been adapted to map local curvature of the bent crystals. One of these, a variation of Berg–Berrett topography, has been used to quantify the diffraction effects caused by the distortion of the crystal wafer. This technique produces a global mapping of the deviation of the diffraction angle relative to a perfect cylinder. Finally, this information is critical for improving bending and measuring tolerances of imperfections by correlating this mapping to areas of missing intensity in the beam.},
doi = {10.1107/S1600577517014059},
journal = {Journal of Synchrotron Radiation (Online)},
number = 6,
volume = 24,
place = {United States},
year = {Thu Oct 19 00:00:00 EDT 2017},
month = {Thu Oct 19 00:00:00 EDT 2017}
}
Web of Science
Works referencing / citing this record:
Characterization and on-line adjustment of the sagittal-bent Laue crystal profile
journal, August 2018
- Dong, Weiwei; Cai, Quan; Yang, Fugui
- Journal of Synchrotron Radiation, Vol. 25, Issue 5