XUV probing of warm dense matter

The measurements were significantly higher than the predictions by Shaffer et al, and were not consistent with the predictions of a weak dependence on photon energy in this range. Refractive index measurements were inconclusive due to ambiguity in the measurements of the phase shift, though this proved valuable as a proof-of-concept for future work.<br><br>The analysis methods used here are a significant advancement over those used in previous work.

One of these is to the diffraction modelling code; the ability to model phase shift of the light passing through the sample has been developed and allows the real part of the sample's refractive index to be measured for the first time. The error analysis methods are now done in a more systematic manner, allowing for more confidence in the error estimates at each stage of the process. The experiment design was also improved, resulting in additional data being collected that was not possible previously, more samples being measured, and more confidence in some of the assumptions that were required for the analysis.

These factors allow for higher confidence in the final bulk property measurements than in the previous work on this project by Kettle et al., despite the similar error estimates.