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A theoretical model is presented describing the spatial structure and scaling laws of laser driven ablative implosions. The effect of inhibited electron thermal transport is explicitly included. The theory is in excellent agreement with results from a computer hydrodynamics code, under conditions when heat flow is flux-limited at the critical surface and suprathermal electrons do not form a dominant energy transport mechanism.

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Gold disks have been irradiated with 1.06 μm laser light at intensities between 7 × 1013 and 3 × 1015 W/cm2, and pulse lengths between 200 and 1000 psec. Due to the high Z and long pulse, inverse bremsstrahlung becomes an important absorption mechanism and competes strongly with resonance absorption and stimulated scattering. In addition to measured absorptions, data on the temporal, spatial, angular, and spectral characteristics of the x-ray emission are presented. Temporally and spectrally resolved back-reflected light, and polarization-dependent sidescattered light are detected, providing estimates for the amount of stimulated scattering and of the coronal electron temperature. Inhibited electron thermal conduction and nonlocal thermodynamic equilibrium ionization physics play key roles in bringing numerical simulations of these experiments into agreement with all of the above-mentioned data.

There is a large region of density-temperature space in which the effects of a magnetic field on heat transport and alpha-particle mobility are significant and the magnetic pressure is small compared with the pressure of a deuterium-tritium plasma. Spherical fusion burn in this regime is examined. It is found that for volume burn, magnetic fields can greatly increase the yield. In regimes where propagating burn does not occur, the burn can be enhanced by a magnetic field. In regimes where propagating deflagration would normally occur in the absence of a magnetic field, magnetic fields actually degrade the cross-field propagation. A detonation wave is harder to ignite in the presence of a magnetic field. Once a detonation wave is ignited, no change in the propagation speed is produced by applying a magnetic field.