X-ray phase-contrast techniques can measure electron density gradients in high-energy-density plasmas through refraction induced phase shifts. An 8 keV Talbot-Lau interferometer consisting of free standing ultrathin gratings was deployed at an ultra-short, high-intensity laser system using K-shell emission from a 1-30 J, 8 ps laser pulse focused on thin Cu foil targets. Grating survival was demonstrated for 30 J, 8 ps laser pulses. The first x-ray deflectometry images obtained under laser backlighting showed up to 25 image contrast and thus enabled detection of electron areal density gradients with a maximum value of 8.1 +/- 0.5 x 10(23) cm(-3) in a low-Z millimeter sized sample. An electron density profile was obtained from refraction measurements with an error of < 8. The 50 +/- 15 mu m spatial resolution achieved across the full field of view was found to be limited by the x-ray source-size, similar to conventional radiography. (C) 2016 AIP Publishing LLC.
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