Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-Ray Preheat
- Lawrence Livermore National Laboratory, L-356, P.O. Box 808, Livermore, CA 94551 (United States)
To drive shocks into solids with a laser we either illuminate the material directly, or to get higher pressures, illuminate a plastic ablator that overlays the material of interest. In both cases the illumination intensity is low, <<1013 W/cm2, compared to that for traditional laser fusion targets. In this regime, the laser beam creates and interacts with a collisional, rather than a collisionless, plasma. We present scaling relationships for shock pressure with intensity derived from simulations for this low-intensity collisional plasma regime. In addition, sometimes the plastic-ablator targets have a thin flash-coating of Al on the plastic surface as a shine-through barrier; this Al layer can be a source of hot x-ray preheat. We discuss how the preheat affects the shock pressure, with application to simulating VISAR measurements from experiments conducted on various lasers on shock compression of Fe.
- OSTI ID:
- 20875706
- Journal Information:
- AIP Conference Proceedings, Vol. 845, Issue 1; Conference: American Physical Society Topical Group conference on shock compression of condensed matter, Baltimore, MD (United States), 31 Jul - 5 Aug 2005; Other Information: DOI: 10.1063/1.2263589; (c) 2006 American Institute of Physics; Country of input: International Atomic Energy Agency (IAEA); ISSN 0094-243X
- Country of Publication:
- United States
- Language:
- English
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