The Study of Second-order Contamination Caused by Multiple Diffraction in a Ge(113) Monochromator

Article type: Research Article

Authors: Seong, B.S. | Shin, E. | Lee, C.H. | Em, V.T. | Shim, H.S.

Affiliations: HANARO Center, Korea Atomic Energy Institute, Taejeon 305-600, South Korea

Note: [] Corresponding author. Tel.: +82-424684441, Fax: +82-42-868-8448. E-mail: it-sej@kaeri.re.kr

Abstract: Neutron intensities of the main wavelength (λ), the second-order (λ/2) and the third-order (λ/3) components in the Ge(113) reflecJed reactor beam were measured by the time-of-flight method for wavelength λ from 1.6 up to 2.41 Å. The measurements have been made as a function of the azimuthal angle Ψ of a Ge(113) monochromator rotation around the scattering vector. It is shown that the secondorder component caused by multiple diffraction is present over a wide interval of angle Ψ and its maximum value increases with wavelength. The second-order contamination can be avoided or decreased by the proper orientation of the monochromator.

Keywords: Multiple diffraction, Ge monochromator, Second-order contamination, Neutron diffraction

DOI: 10.1080/10238160108200164

Journal: Journal of Neutron Research, vol. 9, no. 2-4, pp. 363-371, 2001