X-ray microanalysis near an absorption edge using synchrotron radiation: How to obtain quantitative results

X-ray absorption microanalysis by contact microscopy with synchrotron radiation potentially offers the advantages of high resolution and large fields. However, difficulties appear when quantitative results are required, due in particular to the image detectors that are used. The degree of confidence in quantitative results is examined for photographic detectors. Computer processing is performed taking into account several factors such as the recording process, emulsion response, alignment of image pairs for subtraction, presence of harmonics in the synchrotron beam. As an example we show the analysis of nickel in 20 μm thick polymetallic nodule section on an area of 5.1 × 5.1 mm².