Multiwave Picosecond Laser Interferometry of CO2-Laser-Produced Plasmas
Recently there has been much discussion centered around the production of fast ions and electrons in laser-produced plasmas. Malone et al.,1 at Los Alamos, found that the observed particle distributions could be explained by anomalously low thermal conductivity which would lead to decoupling of the corona from the dense core, overheating of the corona, and thus producing very non-Maxwellian particle distributions. Kidder2 actually speculated on this same type of decoupling for different reasons much earlier. The crucial assumption being made was that the density changed slowly in space from the underdense portion of the plasma to well above critical. The role of photon pressure or ponderomotive forces was probably underestimated in this earlier work. More recent theoretical work3 indicates that many of the same effects can be obtained if one speculates that severe density profile modifications occur due to the photon pressure exceeding the plasma pressure.
KeywordsOptical Pulse Ruby Laser Laser Produce Plasma Pockels Cell Abel Inversion
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