Scaling of Pressure with Intensity in Laser-Driven Shocks and Effects of Hot X-ray Preheat
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, <<10{sup 13} W/cm{sup 2}, 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 flashcoating 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.
- Research Organization:
- Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)
- Sponsoring Organization:
- USDOE
- DOE Contract Number:
- W-7405-ENG-48
- OSTI ID:
- 883506
- Report Number(s):
- UCRL-CONF-215123; IM #324333; TRN: US200615%%76
- Resource Relation:
- Journal Volume: 845; Conference: Presented at: American Physical Society Topical Conference on Shock Compression of Condensed Matter, Baltimore, MD, United States, Jul 31 - Aug 05, 2005
- Country of Publication:
- United States
- Language:
- English
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