Published online by Cambridge University Press: 06 March 2019
Position-sensitive detectors (PSD's) are commonly available for X-ray diffraction, where they are used in the angle dispersive mode at fixed wavelength λ. They are sensitive to the scattering angle 2Θ. The resolution of such instruments is determined by the physical properties of the detector, and, of course, the distance from the sample. Using continuous radiation solid state detectors (Ge, Ge(Li), Si(Li)) are sensitive to energy (equivalent to λ) at fixed scattering angle 2Θo, They are being used for X-rays, especially with synchrotron radiation. Because X-rays travel with the speed of light, those two techniques cannot be combined. Thermal neutrons, on the other hand, are comparatively slowly traveling particles (2200 m/s at 300 K) and consequently time-of-flight (TOF) instruments with choppers at continuous neutron beams are known for a long time; they are being used as well for diff-actomet! y as for inelastic scattering.