Radiative Preheat in Strongly Coupled, Laser Accelerated Plasmas
Abstract
A 1-D radiation hydrodynamics code is employed to model the interaction of the NIKE KrF laser with a planar CH target. Three cases are compared to demonstrate the effects of radiative preheat: (1) the hydrodynamics of the laser target interaction with a high density equation-of-state (EOS) but without radiation; (2) the inclusion of radiation production and transport using collisional radiative equilibrium for the ionization dynamics; and (3) the addition of an approximate model for the pressure ionization and continuum lowering in the ionization dynamics. These last aspects are shown to significantly affect the results due to the strongly coupled plasma state of the compressed, accelerated target. As one moves from case (1) to (3) the density gradient near the ablation front is substantially reduced, implying a decrease in the Rayleigh-Taylor instability growth rates, but at the consequence of a hot and broad accelerating target. Furthermore, the photon spectra emerging from the rearside of the target is shifted in case (3) as compared to (2) toward higher energies and away from the absorption peak of neutral DT fuel.
Document Details
- Document Type
- Technical Report
- Publication Date
- May 14, 1993
- Accession Number
- ADA265442
Entities
People
- Jack Davis
- John L. Giuliani Jr.
- Margaret Mulbrandon
Organizations
- United States Naval Research Laboratory