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Title: Compact Fixed-exit UHV DCM for XAFS

Abstract

A double-crystal, UHV-compatible monochromator for XAFS applications at bending magnet beamlines has been designed. It uses two crystal sets, Si(111) and (311), on a common central rotation axis driven by an ex-vacuo goniometer. All mechanical and electrical components are mounted on a 400 mm UHV flange which is attached to a compact vacuum chamber. The first crystals are water cooled using connector- and bellowless tubing through the fluidic sealed feedthrough of the central rotation. The first crystal set is mounted off-axis and can be translated vertically to keep the fixed exit condition. The second crystal set uses small crystals of the same size as the first. In order to accept the reflected beam of the first crystal at small Bragg angles, it is tangentially translated along the beam. The angle can be varied from 5 deg. to 55.5 deg. resulting in a total energy range 2.4 - 43.4 keV for Si(111)/(311). Crystal sets are interchangeable by translating the vacuum chamber. Angle encoding is achieved by a Renishaw incremental optical encoder in vacuo.

Authors:
; ; ; ; ; ; ;  [1]
  1. Hamburger Synchrotronstrahlungslabor HASYLAB am Deutschen Elektronen-Synchrotron DESY, Notkestr. 85, D-22607 Hamburg (Germany)
Publication Date:
OSTI Identifier:
21052667
Resource Type:
Journal Article
Resource Relation:
Journal Name: AIP Conference Proceedings; Journal Volume: 879; Journal Issue: 1; Conference: 9. international conference on synchrotron radiation instrumentation, Daegu (Korea, Republic of), 28 May - 2 Jun 2006; Other Information: DOI: 10.1063/1.2436208; (c) 2007 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
43 PARTICLE ACCELERATORS; ABSORPTION SPECTROSCOPY; BEAM BENDING MAGNETS; BEAM PRODUCTION; BRAGG REFLECTION; CRYSTALS; FINE STRUCTURE; KEV RANGE; MONOCHROMATORS; PHOTON BEAMS; ROTATION; X RADIATION; X-RAY SPECTRA; X-RAY SPECTROSCOPY

Citation Formats

Rickers, K., Brueggmann, U., Drube, W., Herrmann, M., Heuer, J., Welter, E., Schulte-Schrepping, H., and Schulz-Ritter, H. Compact Fixed-exit UHV DCM for XAFS. United States: N. p., 2007. Web. doi:10.1063/1.2436208.
Rickers, K., Brueggmann, U., Drube, W., Herrmann, M., Heuer, J., Welter, E., Schulte-Schrepping, H., & Schulz-Ritter, H. Compact Fixed-exit UHV DCM for XAFS. United States. doi:10.1063/1.2436208.
Rickers, K., Brueggmann, U., Drube, W., Herrmann, M., Heuer, J., Welter, E., Schulte-Schrepping, H., and Schulz-Ritter, H. Fri . "Compact Fixed-exit UHV DCM for XAFS". United States. doi:10.1063/1.2436208.
@article{osti_21052667,
title = {Compact Fixed-exit UHV DCM for XAFS},
author = {Rickers, K. and Brueggmann, U. and Drube, W. and Herrmann, M. and Heuer, J. and Welter, E. and Schulte-Schrepping, H. and Schulz-Ritter, H.},
abstractNote = {A double-crystal, UHV-compatible monochromator for XAFS applications at bending magnet beamlines has been designed. It uses two crystal sets, Si(111) and (311), on a common central rotation axis driven by an ex-vacuo goniometer. All mechanical and electrical components are mounted on a 400 mm UHV flange which is attached to a compact vacuum chamber. The first crystals are water cooled using connector- and bellowless tubing through the fluidic sealed feedthrough of the central rotation. The first crystal set is mounted off-axis and can be translated vertically to keep the fixed exit condition. The second crystal set uses small crystals of the same size as the first. In order to accept the reflected beam of the first crystal at small Bragg angles, it is tangentially translated along the beam. The angle can be varied from 5 deg. to 55.5 deg. resulting in a total energy range 2.4 - 43.4 keV for Si(111)/(311). Crystal sets are interchangeable by translating the vacuum chamber. Angle encoding is achieved by a Renishaw incremental optical encoder in vacuo.},
doi = {10.1063/1.2436208},
journal = {AIP Conference Proceedings},
number = 1,
volume = 879,
place = {United States},
year = {Fri Jan 19 00:00:00 EST 2007},
month = {Fri Jan 19 00:00:00 EST 2007}
}
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