Analysis and implementation of a space resolving spherical crystal spectrometer for x-ray Thomson scattering experiments

Abstract

The application of a space-resolving spectrometer to X-ray Thomson Scattering (XRTS) experiments has the potential to advance the study of warm dense matter. This has motivated the design of a spherical crystal spectrometer, which is a doubly focusing geometry with an overall high sensitivity and the capability of providing high-resolution, space-resolved spectra. A detailed analysis of the image fluence and crystal throughput in this geometry is carried out and analytical estimates of these quantities are presented. This analysis informed the design of a new spectrometer intended for future XRTS experiments on the Z-machine. The new spectrometer collects 6 keV x-rays with a spherically bent Ge (422) crystal and focuses the collected x-rays onto the Rowland circle. The spectrometer was built and then tested with a foam target. The resulting high-quality spectra prove that a spherical spectrometer is a viable diagnostic for XRTS experiments.

Constraining preheat energy deposition in MagLIF experiments with multi-frame shadowgraphy

“…Finally, an axially resolved (along the ZBL propagation direction), temporally integrated Ar Kshell spectrum is recorded using a spherical crystal spectrometer. 14 Because the gas cell targets use the same LEH foil design and only minimal dopants in the D 2 gas fill, they are thought to be good surrogates for laser preheat in integrated MagLIF targets. The primary difference is the absence of an applied axial (along the direction of laser propagation) magnetic field which is present in integrated experiments but not in Pecos.…”

Benchmark Experiment for Photoionized Plasma Emission from Accretion-Powered X-Ray Sources

“…The Z-pinch radiation is ~10 7 times brighter than the Si emission and the discharge produces high energy background X-rays, mechanical shock, and plasma debris that can ruin data and destroy spectrometer crystals. This problem was overcome by developing a concave spherical crystal (quartz 10-10) spectrometer in the FSSR-1D [49] configuration, achieving high sensitivity (<0.25 [1.85 keV]-photon/µm 2 on detector) and high spectral resolution (λ/δλ=2800-4400).…”

X-ray focusing properties of doubly bent crystals

“…Sagittal focusing properties related to spherical curved crystals (case 3 in Table 1) have been investigated by several authors, and some equations in relation to sagittal focusing position, focal length and magnification have been derived and introduced (Harding et al, 2015;Blasco et al, 2001;Wang et al, 2016;Sinars et al, 2003). It has been also mentioned that, for a spherical curved crystal, the sagittal position lies on the line passing through the point source, S, and the horizontal curvature centre of the diffracting plane, O, which (a) Illustrating the two groups of solutions to equations (13) and 14for the detector plane position indicated by C in Fig.…”