High Energy-Resolution, Low Power XRF and XAFS Spectrometers of Washington University

Abstract

Two types of spectrometers developed in Seidler's Laboratory at University of Washington, Seattle, are explained. These two types are now commercially available. The X-ray tube power is from 20 to 50 watts, forced air cooled. The author of the present paper (Jun Kawai) visited Seidler's laboratory in August 2017. Seidler's XRF spectrometer is high resolution in energy and can measure one sulfur spectrum within 15 minutes, which is a similar energy resolution and sensitivity to a double-crystal spectrometer made by Gohshi 40 years ago with kW water cooled X-ray tube. The key elements are focusing analyzing crystal and cheap 2D CMOS X-ray detector with 200 eV energy resolution. Seidler's XAFS spectrometer is high resolution and again an XANES-EXAFS spectrum can be measured within 30 minutes. This XAFS spectrometer can also measure XRF spectra. An important technique of developing these spectrometers is the 3D printer.