Electronic property measurements of solid density plasmas with x-ray scattering

Summary form only given, as follows. We have recently succeeded measuring the temperature and ionization balance of a previously unexplored regime of high density matter with a proof-of-principal experiment at the Omega laser facility. We used spectrally-resolved 4.75-keV x-ray scattering from solid-density beryllium and carbon plasmas. Spectrally resolved x-ray scattering provides for the first time detailed information on electron densities, temperature, and velocity distributions. In our experiments, we observe the Compton-downshifted spectral line that is broadened by the thermal motion of the electrons in the plasma. These are the first measurements from a solid-density plasma close to the Fermi degenerate state that is a fundamental state of matter occurring in many high energy density laboratory experiments. We compare our results with calculations of the ionization balance using the activity expansion method and an averaged atom model. In this regime, we find that the experimental data test models of electronic properties at high density. These results also suggest that the full range of dense plasmas, from Fermi degenerate, to strongly coupled, to high temperature ideal gas plasmas will now be accessible.