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Nonlinear Mixing of Electromagnetic Waves in Plasmas INTEREST IN NONLINEAR MIXING OF ELECTROMAGNETIC waves in plasmas (particularly beat-wave plasma interaction) began more than two decades ago with the theoretical paper [...]

An analysis of the effects of ion trapping on ion acoustic waves excited by the stimulated Brillouin scattering of crossing intense laser beams is presented. Ion trapping alters the dispersion of ion acoustic waves by nonlinearly shifting the normal mode frequency and by reducing the ion Landau damping. This in turn can influence the energy transfer between two crossing laser beams in the presence of plasma flows such that stimulated Brillouin scattering (SBS) occurs. The same ion trapping physics can influence the saturation of SBS in other circumstances. A one-dimensional analytical model is presented along with reasonably successful comparisons of the theory to results from particle simulations and laboratory experiments. An analysis of the vulnerability of the National Ignition Facility Inertial Confinement Fusion point design [S. W. Haan et al., Fusion Sci. Technol. 41, 164 (2002)] is also presented. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Addresses theoretical issues associated with the use of pulsed reflectometry with particular emphasis on applications in the Sustained Spheromak Physics Experiment at the Lawrence Livermore National Laboratory. Simulation results presented for O- and X-mode mixed-polarization reflectometry and linear mode conversion in two spatial dimensions; Profile reconstruction algorithms.

Analyzes the resonant stimulated Brillouin interaction of opposed laser beams in a drifting plasma. Dependence of energy transfer and ion wave dynamics on laser intensities; Use of particle simulations and solutions of coupled mode equations for energy transfer analysis.

Examines the suppression of stimulated Brillouin backscattering (SBBS) by seeded ion wave mode coupling. Reduction of the primary ion wave and backscatter amplitude; Use of the BZOHAR two-dimensional hybrid simulation code; Importance of SBBS in laser fusion.

Reports on the generalization of a Landau-fluid model to the full range of ion and electron collisionality and its application to a fluid simulation code constructed to study laser filamentation in underdense plasmas. Expressions for linear susceptibilities in the presence of a finite-amplitude pump.

Presents results of studies on the scattering phase shift of S-polarized O modes in fluctuation reflectometry both within and beyond the Born approximation. Description of the HELM1D numerical one-dimensional Helmholtz equation solver; Integral representation for the scattering phase shift within the Born approximation.

This section presents abstracts of research and articles on international economics, published in the December 1966 issue of the Journal of Economic Abstracts. The article American Coal in Western Europe by M. A. Adelman studies the feasibility of exporting U.S. Steam coal to Western Europe. The article Fiscal Policy: Duties and Inducements by A. Bain concerns itself with the structure of Great Britain's tax system and its balance of payments. It concludes that major tax reforms are not the key to improving Great Britain's balance of payments, although some changes would probably be both justifiable and helpful. Authors R. J. Ball, J. R. Eaton and M. D. Steuer investigate the supply of the side of the hypothesis that internal pressure of demand affects export performance. The hypothesis suggests that at relatively high levels of internal demand, other things being equal, the quantity of resources devoted to exports is lower than would have been the case at lower levels of demand. G Basevi's article, The U.S. Tariff Structure: Estimates of Effective Rates of Protection of U.S. Industries and Industrial Labor, presents the theory of tariff structure, and extends this theory by arguing that for the U.S., and even for underdeveloped countries, effective protection should be referred to the share of value added by labor rather than to total value added.