To achieve this exceptional performance, the XEPOS combines a unique excitation system comprising of closely coupled, Optimised Excitation by Target geometry, and a state-of-the-art Silicon Drift detector (SDD). A choice of up to 8 polarising and secondary metal targets gives optimal excitation for the application. This results in high sensitivity together with low background signals which therefore dramatically improves detection limits. A 50W X-ray tube allows the use of preferred spectral lines, even for heavy elements. The SDD, which does not require liquid nitrogen cooling, has good spectral resolution at high count rates for reduced measuring times and improved accuracy, coupled with excellent signal-to-noise characteristics, again contributing to improved detection limits.
The software and user interface have been developed to make this analytical power easily accessible to the user. Only three simple steps are needed to perform a routine analysis using a stored method, and only five to create a new one. For unknown samples, SPECTRO ANALYTICAL has developed TurboQuant, an expert system package that automatically calculates and corrects for matrix effects.
The detection limits achievable with XEPOS have made it especially popular for environmental analyses like screening soils for contamination by heavy metals where low fractions of parts per million detection limits are routinely achievable, or the measurement of sulphur, chlorine and trace metals in waste oils, where its speed and simplicity mean that these analyses can be done in real time.
This ability is essential in techniques like Chemostratigraphy, used in oil exploration to correlate oil and gas reservoirs. Geoscience consultancy Ichron Limited use a XEPOS to carry out analysis directly at wellsite, where, the company says “the small size, robust construction and rapid turnaround of data make the XEPOS the ideal tool for near ‘real-time’ chemostratigraphic analyses.”