A laboratory-based tender X-ray spectrometer for X-ray absorption fine structure measurements

摘要: This paper describes the design and performance of a laboratory-based tender X-ray spectrometer for X-ray absorption spectroscopy. The system enables effective absorption spectra measurement within the 2.0-9.0 keV range using Rowland circle geometry: it covers the K edge of 3d transition metals, the L edge of lanthanides and the M edge of actinides. The spectrometer is configured with a 500 mm diameter Rowland circle and integrates a 250 W liquid metal-jet X-ray source, a spherical bent crystal analyzer, and an energy-resolving silicon drift detector. The X-ray source is installed outside the vacuum chamber and remains fixed, while the analyzer crystals and detector are adjusted to change the Bragg angle while maintaining the Rowland condition. The energy resolution is 0.36 - 1.30 eV at 2.0 - 9.0 keV, and the monochromatic flux is approximately 5×105 counts/s at 7040 eV. This paper highlights the main characteristics of the spectrometer and demonstrates its capabilities through selected experimental examples. The successful development of this spectrometer especially facilitates research on actinide elements, which are often constrained in synchrotron radiation experiments due to their radioactivity, thus fostering advancements in related nuclear energy fields.