LAUSR

With the advent of the wavelength dispersive spectrometer WDS detecting X-rays with an incorporated high resolution silicon drift detector (SDD), referred to as SD-WDS [1-3], it is now possible to simultaneously measure the bremsstrahlung at the peak intensity by measuring the second order diffraction peak and applying an algorithm to calculate the equivalent background under the first order peak. This calculation is not necessarily available for every element in the spectrometer, but can be used along with the EDS background to calculate, reasonably accurately, the background under the peak. One of the biggest time consuming measures when using the WDS, is measuring the backgrounds by moving the spectrometers to both sides of the WDS peak. For trace elements this means at least double the collection time of the peak count. This talk discusses where a calculated background is possible and how it can be achieved. The SD-WDS spectra are taken from four different SD-WDS spectrometers using the crystals LIF, PET, TAP and STE at 20keV on a carbon coated Cu sample.