Extreme ultraviolet probing of laser imprint in a thin foil using an x-ray laser backlighter

Conference item

For direct drive inertial confinement fusion, a capsule is imploded by directly illuminating the surface with laser light. Beam smoothing and uniformity of illumination affect the seeding of instabilities at the ablation front. We have developed a technique for studying the imprint of a laser beam on a thin foil using an x-ray laser as an extreme ultraviolet (XUV) backlighter. We use multilayer XUV optics to relay the x-ray laser onto the directly driven foil, and then to image the foil modulation onto a charged coupled device camera. This technique allows us to measure small fractional variations in the foil thickness. We have measured the modulation due to imprint from a low intensity 0.35 mu m drive beam incident on a 3 mu m Si foil using an yttrium x-ray laser on Nova. We present results from a similar technique to measure the imprinted modulation due to a low intensity 0.53 mu m drive beam incident on a 2 mu m Al foil using a germanium x-ray laser at the Vulcan facility. (C) 1997 American Institute of Physics.

Authors: Kalantar, D; DaSilva, L; Glendinning, S; Remington, B; Weber, F

• Publication status: Published
• Journal: REVIEW OF SCIENTIFIC INSTRUMENTS
• Volume: 68
• Issue: 1
• Pages: 802-805
• Publication date: 1997-01-01
• Event title: 11th Topical Conference on High-Temperature Plasma Diagnostics
• DOI: 10.1063/1.1147747
• ISSN: 0034-6748
• Keywords: BEAM; INDUCED SPATIAL INCOHERENCE