Source, optical and detector requirements for X-ray diffraction and scattering

The standard curves used to describe the properties of synchrotron radiation sources usually consist of a plot of the flux or brightness from the source as a function of wavelength. These curves are useful for the case where a high flux or brightness is required. Many experiments do not fall into this category. An alternative description of the source requirements is to provide the maximum flux into the phase space volume defined by the specimen. A diagrammatic way of illustrating how this can be achieved is derived. This illustrates how the source, optics and detectors can be matched to the requirements of a particular experiment. This approach is illustrated using, as examples, a beamline on the SRS and two beamlines planned for DIAMOND, the proposed new UK third-generation source.