Density and temperature profiles in strongly absorbing plasma with distributed absorption

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Abstract
A model is presented of the spatial structure of a laser‐heated, strongly absorbing, planar plasma. Inverse bremsstrahlung is very strong so that laser light absorption is not localized. Absorption is distributed over densities from well below critical to the critical density. It is shown that the spatial structure of the plasma is self‐consistent with laser energy deposition and heat transport so measurement of the plasma structure can be used as diagnostic of absorption and transport. Nonphysical discontinuities in density and temperature at the critical surface that are predicted by previous local absorption models for strongly flux‐limited heat transport are reduced. These jumps persist in the present model. It is shown that an improved flux‐limited heat transport model, strongly limited in the underdense plasma and weakly limited in the overdense plasma, results in continuous density and temperature profiles.