High-resolution two-axis diffractometer
A typical neutron powder diffraction experiment with D2B:
- The polychromatic beam from the thermal beam H11 is collimated and is diffracted by the Ge monochromator at a large take-off angle to obtain high resolution.
- The sample - usually a cylinder of powder - diffracts the monochromatic incident beam. The sample is often placed inside a cryostat, a furnace, etc.
- The Bragg reflections are mesured by a bank of 128 detectors spaced at 1.25° intervals, covering the angular range about 4° to 160º. The detectors are moved so that counts are averaged over several detectors.
- Depending on the choosen wavelenght and/or resolution, the typical acquisition time for a pattern varies from 1h to 8h.