Four-circle diffractometer with three-axis energy analysis

Simulated experiment (TAS geometry)

Here D10 is set in the 3-axis geometry (TAS geometry) for an inelastic scattering experiment.

  • The polychromatic beam from the thermal neutron guide H24 arrives on the monochromator, which selects a given wavelength.
  • The monochromatic beam passes through slits to limit its size before reaching the sample.
  • The sample, usually a single crystal in a gas flow helium cryostat, is at the centre of the Eulerian cradle.
  • The sample is first rotated to the desired orientation.
  • The scattered beam, which may have a different wavelength from the incident beam, arrives on the analyser.

To obtain the wavelength (or energy) of the scattered beam, a scan is performed by the analyser and detector.

This makes it possible to study the dynamics of materials and also to measure very small signals, e.g. diffuse scattering, and very weak magnetic peaks.