Journal Article

FZJ-2015-00764

http://join2-wiki.gsi.de/foswiki/pub/Main/Artwork/join2_logo100x88.png The first prototype diamond monochromator at the Institut Laue-Langevin

Courtois, P. (Corresponding Author)Extern* ; Fernandez-Diaz, M. T. ; Nenert, G. ; Andersen, K. H. ; Freund, A. K. ; Gsell, S. ; Fischer, M. ; Schreck, M. ; Link, P.MLZ* ; Meven, M.FZJ*

2014
IOP Publ. Bristol

This record in other databases:  

Please use a persistent id in citations: http://hdl.handle.net/2128/9091  doi:10.1088/1742-6596/528/1/012001

Abstract: We report on the performance of the first diamond neutron monochromator built at the ILL. It has been designed for the hot neutron diffractometer D9 with the aim of improving significantly the instrument performance in particular for short wavelengths in the 0.3-0.9 Å wavelength range. Diamond crystal plates with dimensions of 1.5 x 1.5 x 0.18 cm3 and an average mosaic spread of 0.15° have been synthesized at the University of Augsburg. They exhibited excellent neutron diffraction properties when examined on a neutron double-crystal test setup. Sufficiently thick diamond elements with a controlled mosaic spread of 0.25° have been obtained by stacking several of these crystals. First tests runs carried out at the ILL confirmed the predicted high reflectivity of the diamond stacks. The diamond prototype monochromator uses the (220) reflection in transmission geometry replacing the Cu (220) monochromator on D9 that has the same d-spacing. The final performance studies on D9 showed that the diamond device did not perform better than the original copper crystal. This unexpected result could be explained by significant optical aberrations caused by nonuniformities of both the angular and spatial mosaic distribution in the individual diamond crystals, as revealed by a detailed characterisation study using high-energy X-ray diffraction.

Keyword(s): Instrument and Method Development (1st) ; Others (1st) ; Instrument and Method Development (2nd)

---

Contributing Institute(s):

1. JCNS-FRM-II (JCNS (München) ; Jülich Centre for Neutron Science JCNS (München) ; JCNS-FRM-II)
2. Streumethoden (JCNS-2)
3. Streumethoden (PGI-4)
4. JARA-FIT (JARA-FIT)

Research Program(s):

1. 54G - JCNS (POF2-54G24) (POF2-54G24)

Experiment(s):

1. HEiDi: Single crystal diffractometer on hot source (SR9b)
2. Neutron Optics

Appears in the scientific report 2014

---

Database coverage:
; ; ; ; Nationallizenz ; SCOPUS

---