Development of a compact vacuum flat-crystal spectrometer for X-ray studies of L-shell multi-ionized atoms

Abstract

We present the development of a highly compact vacuum flat-crystal spectrometer designed for the precise analysis of X-ray spectra of L-shell multi-ionized atoms. The design incorporates a mathematical framework to elucidate the influence of geometrical parameters on spectral bandwidth, energy resolution, and detection efficiency. The spectrometer operates over an energy range of 0.53–19.3 keV, achieving a single-exposure spectral bandwidth of 0.04–6.58 keV. This performance is achieved by the combination of multiple flat crystals and a design featuring linear target motion synchronized with crystal rotation, allowing Bragg angle modulation from 25° to 65°. The spectrometer was calibrated using L-series X-ray generated by 10 keV electron beam interactions with a solid silver target. Comparative performance tests indicated that the resolving power of the mosaic HOPG(002) crystal exceeds 400, while the perfect Si(111) crystal approaches 500. However, the mosaic HOPG exhibited over 20 times higher detection efficiency, making it especially effective for detecting rare transitions in high-sensitivity X-ray spectroscopy. This spectrometer offers broad applicability across diverse fields, including chemical effects on X-ray parameters, synchrotron radiation experiments, laser plasma diagnostics, and laboratory astrophysics.