ENHANCED SCATTERING IN MAGNETIZED LASER-PRODUCED PLASMA

A simple model of Bernstein mode parametric excitation near the electr on plasma frequency in a subcritical laser-produced plasma is presente d. It is argued that the instability threshold of such modes might bec ome much lower than the usual thresholds for both convective and absol ute Raman scattering, in particular, near the so-called ''omega(qn)'' resonances. This would occur in high-temperature plasmas (2-5 keV) and over very small (about ten microns long) regions of flat magnetic fie ld and plasma density, corresponding to hot spot locations. A special emphasis is placed on a simplified formulation of the growth rates and thresholds for parameters domains wherein Bernstein mode parametric e xcitation might be of importance, to allow applications in any experim ental situation. Many features of the resulting backscatter compare fa vorably with experimental observations. (C) 1997 American Institute of Physics.