KWS-1

This instrument is focussed on cold neutrons. Therefore, please carefully check the “Technical data WITHOUT cold source” section. Deviating parameters are in bold. The instrument team is happy to answer any further questions!

Instrumentscheme KWS-1

KWS-1 is a small-angle scattering instrument with variable wavelength resolution dedicated to experiments with polarised neutrons and polarisation analysis [1].

A polariser with three cavities, each having a V-shaped supermirror, is placed in front of the collimation and covers the full wavelength band with min. 90 % (95 % typical) polarisation. A radio frequency spin flipper allows reverting the polarisation. The polarisation analysis is realised with an in-situ pumped ³He spin filter, which is optimised for the used wavelength and scattering angle. Horizontal and vertical magnets are provided to render the magnetic field at the sample position. The sample position of KWS-1 is equipped with a hexapod, capable of supporting up to half a ton of useful load enabling magnetic thin films to be investigated via grazing incidence small-angle neutron scattering (GISANS). The MgF₂ lenses are used for the high flux mode with large sample areas, while the resolution stays in the classical SANS range.

For operation without the cold source, the instrument will be equipped with a 20 % tiltable wavelength selector to gain flux, enabling experiments on larger colloids and concentrated soft matter systems together with certain experiments on magnetic materials.

[1] Feoktystov, A. et al., J. Appl. Cryst. 48, 61 (2015).