High-resolution Dante spectrometer based on quasi-monochromatic multilayer mirror array for soft X-ray spectral measurement in plasma diagnostics

Soft X-ray spectroscopic diagnostics based on Dante spectrometers are essential for evaluating plasma conditions driven by Z-pinch or laser fusion. A Dante spectrometer configuration capable of achieving low spectral measurement uncertainty remains a bottleneck problem at present. This paper develops a quantitative uncertainty-analysis framework for Dante spectrometers employing an array of quasi-monochromatic multilayer mirrors. Accordingly, we further developed a set of practical methods, including the precise synchrotron radiation calibration and optimized spectrometer installation, to effectively suppress these measurement uncertainties. For implementation, we developed a Dante spectrometer covering 100-1000 eV and validated it on a Z-pinch platform. The relative expanded uncertainty of individual channels was maintained within 2%-3%, and the reconstructed spectral-distribution uncertainty was better than 3.2%.