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A general view of the instrument D17 is an extremely powerful vertical axis (polarised) reflectometer with a high flux and low background capable of measuring reflectivities down to 10 -7 . It is designed

energy transfer). A velocity selector selects a rather broad Δλ/λ bandwidth (typically 15%) from the incident polychromatic neutron beam. The monochromatic beam is then polarised by a supermirror polariser ... of the spin of the neutron in a magnetic field as un extremely accurate stopwatch. Counting the number of precessions made by the neutron ...

A simulated experiment The incoming polychromatic neutron beam (wavelength around 2.2 Å) is backscattered on the monochromator (Bragg reflexion on a crystal lattice) with a high monochromaticity (energy ... beam is reflected so as to hit the sample. The scattered neutrons are analysed by a Bragg reflexion on the analysers. A chopper creates ...

A general view of the instrument

A general view of IN12 The IN12 instrument - On the left: End of guide shielding with lead tunnel, movable polyethylen shielding of the monochromator castle (blue) as well as the lead exit tunnel (yellow)

A simulated experiment Basics of the so called time-focussing technique Three intense neutron beams are extracted from a neutron guide by an assembly of three monochromators and are focused horizontally ... sample. Each monochromator delivers a beam of distinct energy and, thus, of distinct velocity due to different Bragg-scattering conditions. The ...

studied on a depth of 1 to 300 nm (5 to 1500 atomic layers). If the incident angle is lower than the critical angle, the material acts like a mirror and reflects all neutrons. If it is wider, only a part of ... reflected. Measuring the proportion of reflected neutrons for a reflection angle equal to the incident angle makes it possible to explore ...

A general view of the instrument D23 is shown with the 12 Tesla cryomagnet mounted on.

higher, only a part of the neutrons are reflected. Measuring the proportion of reflected neutrons for a reflection angle equal to the incident angle makes it possible to explore the sample in a direction ... Layer stacking can be studied on a thickness scale of 1 to 500 nm (5 to 2500 atomic layers). If the incident angle is lower than the critical ...