The x-ray laser as a tool for imaging plasmas

The x‐ray laser is now being used at LLNL as a tool for measuring the behaviors of hot dense plasmas. In particular, we have used the 155A yttrium laser to study transient plasmas by both radiography and moire deflectometry. These techniques have been used to probe long scale length plasmas at electron densities exceeding 1022 cm−3. Recent advances in multilayer technology have made it possible to directly image ion densities in directly driven thin foils to an accuracy of 1–2 μm. In addition, we have constructed an x‐ray laser Mach‐Zehnder interferometer using multilayer beam‐splitters. This interferometer yields direct 2D projections of electron densities in plasmas with micron spatial resolution. In addition, this interferometer can be used to measure spectral line shapes to high accuracy. Among the subject plasmas under study are laser irradiated planar targets, gold hohlraums, and x‐ray lasers themselves.