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For single pulsed laser-matter interactions at sufficiently high intensity, the electron density in the ablated
vapor is large enough to absorb the laser radiation before it can reach the dense target material. The resulting
interaction can be described in terms of energy flows: laser energy is absorbed in the plasma in front of the target
and reappears as thermal electron energy and secondary radiation, part of which impinges upon and heats the dense
target material at the dense material-vapor interface. This heating in turn drives ablation, thereby providing a selfconsistent
mass source for the laser absorption, energy conversion, and transmission. Under typical conditions of
laser intensity, pulse width and spot size, the flow patterns can be strongly two-dimensional. We have modified the
inertial confinement fusion code LASNEX to simulate gaseous and some dense material aspects for the relatively
low intensity, long pulse-length conditions of interest in many laser-related applications. The unique aspect of
our treatment consists of an ablation model which defines a dense material-vapor interface and then calculates
the mass flow across this interface. The model, at present, treats the dense material as a rigid, two-dimensional
simulational mass and heat reservoir, suppressing all hydrodynamical motion in the dense material. The modeling
is being developed and refined through simulation of experiments, as well as through the investigation of internal
inconsistencies, and some simulation of model problems. The computer simulations and additional post-processors
provide a wealth of predictions for possible measurements, including impulse given to the target, pressures at
the target interface, electron temperatures and densities, and ion densities in the vapor-plasma plume region,
transmission and emission of radiation along chords through the plume, total mass ablation from the target and
burn-through of the target material at selected radial locations. We will present an analysis of some relatively
well-diagnosed experimental behavior which has been useful in development of our modeling.
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