In X-ray diffraction and wavelength dispersive X-ray fluorescence, it is necessary to determine the intensity of a coherently diffracted X-ray peak with respect to its position, two-theta. To accomplish this, most X-ray diffractometers are provided with a scanning goniometer mounted X-ray detector that scans the angular two-theta region of interest and obtains X-ray Intensity as a function of time and therefore two-theta.