MLZ is a cooperation between:
> Technische Universität München
> Helmholtz-Zentrum Geesthacht
> Forschungszentrum Jülich
MLZ (eng)
Lichtenbergstr.1
85748 Garching
KWS-1
Small angle scattering diffractometer
The KWS-1 is dedicated to high resolution measurements [1] due to its 10% wavelength selector. This property is interesting for highly ordered or highly monodisperse samples. With the foreseen chopper the wavelength uncertainty can be reduced further to ca. 1%. The scientific background of KWS-1 is placed in magnetic thin films. Magnetic samples will be studied with the full polarisation analysis including incident beam polarisation and polarisation analysis of the scattered neutrons. In front of the collimation, a 3-cavity polariser with V-shaped mirrors is placed. The full bandwidth of 4.5 to 20 Å will be covered with min. 90% (95% typical) polarisation. A radio frequency spin flipper allows for changing the polarisation. The polarisation analysis will be realised with 3He-cells which will be optimised for the used wavelength and scattering angle. Vertical magnets will be provided to render the magnetic field at the sample position. Thin films can be well studied in the grazing incidence geometry – the method is called grazing incidence small angle neutron scattering (GISANS). A newly installed hexapod will allow for positioning the sample with 0.01 mm and 0.01° precision.
Classical soft-matter systems will be investigated on KWS-1 if the resolution is needed. Biological samples can be handled due to the detector distance of ca. 1 m, which will allow for maximal scattering angles of Q = 0.5 Å-1.
The MgF2 lenses are used for the high flux mode with large sample areas, while the resolution stays in the classical SANS range. These enhanced intensities allow for real time measurements in the 1/10 second region (typical 1 s).
The chopper in parallel allows for studying faster dynamics in the ms range. The so-called TISANE mode interlocks the chopper frequency with the excitation field frequency and with the detection binning. The precise consideration of the flight times allows for higher precision compared to classical stroboscopic illuminations
[1] Feoktystov, A. et al., J. Appl. Cryst. 48 (2015), 61-70
- Grain boundaries
- Alloys
- Magnetic structures
- Flow lines
- Soft matter and biology (as for KWS-2)
- Complex fluids near surfaces
- Polymer films
- Magnetic films
- Nanostructured films
- Rheometer shear sandwich
- Rheowis-fluid rheometer (max. shear rate 10000 s-1)
- Anton-Paar fluid rheometer
- Stopped flow cell
- Sample holders: 9 horizontal x 3 vertical (temperature controlled) for standard Hellma cells 404-QX and 110-QX
- Oil & water thermostats (range -40 – +250°C), electric thermostat (RT – 200°C)
- 8-positions thermostated (Peltier) sample holder (-40°C – 150°C)
- Magnet (horizontal, vertical)
- Cryostat with sapphire windows
- High temperature furnace
- Pressure cells (500 bar, 2000 bar, 5000 bar)
Overall performance
- Q = 0.0007 – 0.5 Å-1
- Maximal flux: 1.5·108 n cm-2 s-1
- Typical flux: 8·106 n cm-2 s-1 (collimation 8 m, aperture 30 x 30 mm², λ = 7 Å)
Velocity selector
- Dornier, FWHM 10%, λ = 4.5 Å – 12 Å, 20 Å
Chopper
- For TOF-wavelength analysis, FWHM 1%
Polariser
- Cavity with V-shaped supermirror, all wavelengths
- Polarisation better 90%, typical 95%
Spin-flipper
- Radio-Frequency (spin flip probability better than 99.8%)
Active apertures
- 2 m, 4 m, 8 m, 14 m, 20 m
Aperture sizes
- Rectangular 1 x 1 mm2 – 50 x 50 mm2
Sample aperture
- Rectangular 1 x 1 mm2 – 50 x 50 mm2
Neutron lenses
- MgF2, diameter 50 mm, curvature 20 mm
- Packs with 4, 6, 16 lenses
Sample stage
- Hexapod, resolution better than 0.01°, 0.01 mm
Detector 1
- Detection range: continuous 1.5 m – 20 m
- 6Li-Scintillator 1 mm thickness + photomultiplier
- Efficiency better than 95%
- Spatial resolution 5.3 x 5.3 mm2,
- 128 x 128 channels
- Max. countrate 0.6 MHz (τdead = 0.64 μs)
Instrument Scientists
Dr. Henrich Frielinghaus
Phone: +49 (0)89 289-10706
E-Mail: h.frielinghaus@fz-juelich.de
Dr. Artem Feoktystov
Phone: +49 (0)89 289-10746
E-Mail: a.feoktystov@fz-juelich.de
Dr. Lester Barnsley
Telefon: +49 (0)89 289-13805
E-Mail: l.barnsley@fz-juelich.de
KWS-1
Phone: +49 (0)89 289-14324
Operated by
Publications
Find the latest publications regarding KWS-1 in our publication database iMPULSE:
Citation of the instrument
Heinz Maier-Leibnitz Zentrum. (2015). KWS-1: Small-angle scattering diffractometer. Journal of large-scale research facilities, 1, A28. http://dx.doi.org/10.17815/jlsrf-1-26
For citation please always include the DOI.
Gallery
MLZ is a cooperation between:
> Technische Universität München> Helmholtz-Zentrum Geesthacht> Forschungszentrum Jülich