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Title: High Resolution Sapphire Bragg Backscattering Monochromator

Abstract

We present a temperature stabilised high resolution sapphire backscattering monochromator. The device consists of a sapphire crystal inside a cold nitrogen gas cooled, temperature stabilised chamber with a passively temperature stabilised screen. The achieved temperature stability of {+-}2mK allows for an energy resolution of {delta}E/E {<=} 10-7 at energies in the range of 30-70 keV. The device was developed for nuclear resonant scattering above 30 keV, where appropriate solutions did not exist until now.

Authors:
;  [1];  [2]
  1. European Synchrotron Radiation Facility, B.P. 220, F-38043 Grenoble (France)
  2. Argonne National Laboratory, Advanced Photon Source, Argonne, Il-60439 (United States)
Publication Date:
OSTI Identifier:
21052669
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: 10.1063/1.2436210; (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; BACKSCATTERING; CRYSTALS; ENERGY RESOLUTION; KEV RANGE; MONOCHROMATORS; RESONANCE SCATTERING; SAPPHIRE; STABILITY; SYNCHROTRON RADIATION; SYNCHROTRON RADIATION SOURCES; X RADIATION; X-RAY DIFFRACTION

Citation Formats

Linden, P. van der, Wille, H.-C., and Shvyd'ko, Yu. V. High Resolution Sapphire Bragg Backscattering Monochromator. United States: N. p., 2007. Web. doi:10.1063/1.2436210.
Linden, P. van der, Wille, H.-C., & Shvyd'ko, Yu. V. High Resolution Sapphire Bragg Backscattering Monochromator. United States. doi:10.1063/1.2436210.
Linden, P. van der, Wille, H.-C., and Shvyd'ko, Yu. V. Fri . "High Resolution Sapphire Bragg Backscattering Monochromator". United States. doi:10.1063/1.2436210.
@article{osti_21052669,
title = {High Resolution Sapphire Bragg Backscattering Monochromator},
author = {Linden, P. van der and Wille, H.-C. and Shvyd'ko, Yu. V.},
abstractNote = {We present a temperature stabilised high resolution sapphire backscattering monochromator. The device consists of a sapphire crystal inside a cold nitrogen gas cooled, temperature stabilised chamber with a passively temperature stabilised screen. The achieved temperature stability of {+-}2mK allows for an energy resolution of {delta}E/E {<=} 10-7 at energies in the range of 30-70 keV. The device was developed for nuclear resonant scattering above 30 keV, where appropriate solutions did not exist until now.},
doi = {10.1063/1.2436210},
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}
}
  • The resolution function of a powder diffractometer at a synchrotron radiation source increases with increasing Bragg angle of the monochromator. Consequently, a monochromator close to backscattering has been designed and built. Two mosaic crystals of beryllium in nondispersive setting serve as optical elements. They are mounted on goniometer heads inside a tube-like housing which may be evacuated. Fine adjustment of one of the crystals is done with a micro-goniometer driven by a magnetostrictive actuator. The fact that the housing is a tube allows the use of the assembly as part of a multi-purpose monochromator system for powder diffraction.
  • Here, we report on a high resolution sapphire backscattering monochromator installed at the Dynamics beamline P01 of PETRA III. The device enables nuclear resonance scattering experiments on M ossbauer isotopes with transition energies between 20 and 60 keV with sub-meV to meV resolution. In a first performance test with 119Sn nuclear resonance at a X-ray energy of 23.88 keV an energy resolution of 1.34 meV was achieved. Moreover, the device extends the field of nuclear resonance scattering at the PETRA III synchrotron light source to many further isotopes like 151Eu, 149Sm, 161Dy, 125Te and 121Sb.
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