Talbot-Lau x-ray density diagnostic for High Energy Density plasmas

Abstract

Phase-contrast x-ray diagnostics can detect density gradients in low-Z matter with the sensitivity and spatial resolution required in High Energy Density (HED) plasma experiments. Talbot-Lau interferometry measures x-ray beam deviations due to refraction index gradients in its path. It can simultaneously provide x-ray attenuation, refraction, elemental composition, and scatter images of a low-Z object. We have developed the Talbot-Lau Moire X-ray Deflectometry (TXD) single image technique based on phase-retrieval. The results obtained at 8 and 17 keV with high magnification using low-Z test objects suggest a clear advantage of TXD as HED electron density diagnostic over conventional radiography. The Moire technique can detect sharp and smooth density gradients with source-limited spatial resolution. Also, TXD can use extended, incoherent, line or continuum x-ray sources, allowing for a wide range of backlighters.