The bent crystal diffraction spectrometer at the BR2 reactor in Mol

https://doi.org/10.1016/0168-9002(88)90488-3Get rights and content

Abstract

The DuMond-type bent crystal diffraction spectrometer installed at the BR2 reactor in Mol is presented. The spectrometer is mainly designed to study nuclear γ-transitions following thermal neutron capture. It covers the energy interval 25 ≦ Eγ ≦ 1500 keV. Instead of the traditionally used quartz crystals, a highly perfect silicium crystal is chosen as analysing crystal. Diffraction occurs from the (220) plane. The “quasi-mosaic” width, introduced by bending the crystal, is as small as 0.2″. The integrated reflecting power R of the bent crystal stays constant up to 1.5 MeV in first, 680 keV in second and 300 keV in third diffraction order. For higher photon energies, only an E−1 energy dependence is observed in second and third diffraction order. Consequently, besides improving the energy resolution, the use of these silicium crystals substantially increases the spectrometer efficiency and extends the high energy limit of bent crystal diffraction spectrometers.

The diffraction angles are measured with a symmetrical interferometer system which covers an angular range of −6° to +6° with a precision of about 0.01″. Minimum diffraction line widths of 0.9″ have been measured, corresponding to an energy resolution ΔE = 1.35 × 10−6E2n−1 keV−1. The dominant contribution to the observed line widths arises from the finite extent of the source.

References (18)

  • O. Piller et al.

    Nucl. Instr. and Meth.

    (1973)
  • G.L. Borchert et al.

    Nucl. Instr. and Meth.

    (1975)
  • H.R. Koch et al.

    Nucl. Instr. and Meth.

    (1980)
  • L. Jacobs et al.

    Nucl. Instr. and Meth.

    (1977)
  • W. Schwitz

    Nucl. Instr. and Meth.

    (1978)
  • E. Kaerts et al.

    Nucl. Instr. and Meth.

    (1987)
  • Y. Cauchois

    J. Phys. Radium

    (1932)
  • J.W.M. DuMond

    Rev. Sci. Instr.

    (1947)
  • J.W. Knowles

    Nucl. Instr. and Meth.

    (1979)
There are more references available in the full text version of this article.

Cited by (9)

  • Nuclear Data Sheets for A = 165

    2006, Nuclear Data Sheets
View all citing articles on Scopus

Mailing address: SCK/CEN (BRI), Boeretang 200, 2400 Mol, Belgium.

∗∗

Present address: Lens Diamond Industries, De Beerslaan, 2590 Berlaar, Belgium.

+

Present address: Commission of the European Communi-ties, Jean Monnet Building, Kirchberg, Luxembourg.

View full text