Symmetric Laue Diffraction of Spherical Neutron Waves in Absorbing Crystals

  • A. Ya. Dzyublik Institute for Nuclear Research, Nat. Acad. of Sci. of Ukraine
  • V. I. Slisenko Institute for Nuclear Research, Nat. Acad. of Sci. of Ukraine
  • V. V. Mykhaylovskyy Institute for Nuclear Research, Nat. Acad. of Sci. of Ukraine

Abstract

Well-known Kato's theory of the Laue diffraction of spherical x-ray waves is generalized to the case of the neutron diffraction in strongly absorbing crystals, taking into consideration both the potential  and the resonant scattering of neutrons by nuclei. The saddle-point method is applied for estimation of the angular integrals, being more adequate in the case of strongly absorbing crystals than the stationary-phase approximation  used by Kato. It is found that the distribution of intensity of diffracted and refracted beams  along the basis of the Borrmann triangle strongly depends on the deviation of the neutron energy from the  nuclear resonant level.

Author Biography

V. I. Slisenko, Institute for Nuclear Research, Nat. Acad. of Sci. of Ukraine

Corresponding Member of National Academy of Sciences of Ukraine, 
Doctor of Sciences in Physics and Mathematics, 
Head of the Department of Research Reactor. 

Keywords thermal neutrons, Laue diffraction, dynamical scattering theory, spherical waves, Borrmann triangle

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Published
2018-03-02
How to Cite
Dzyublik, A., Slisenko, V., & Mykhaylovskyy, V. (2018). Symmetric Laue Diffraction of Spherical Neutron Waves in Absorbing Crystals. Ukrainian Journal Of Physics, 63(2), 174. Retrieved from https://ujp.bitp.kiev.ua/index.php/ujp/article/view/38/53
Section
Structure of materials