SPONTANEOUS EMISSION EFFECTS IN NONLINEAR-INTERACTIONS OF NONRESONANTWAVES WITH RESONANT PLASMA FLUCTUATIONS

Spontaneous emission effects on propagation of nonresonant waves in pl asmas in the presence of resonant fluctuations are studied. It is demo nstrated that in closed plasma systems the number of nonresonant quant a is conserved as an adiabatic invariant. The conservation is due to t he vanishing polarizational contribution that resulted from the symmet ry of the system as well as to the balance of the direct nonlinear cou pling and reverse absorption by particle collisions. Energy of the non resonant waves as well as their amplitudes may vary with time even whe n the resonant field fluctuations are at the thermal level. (C) 1996 A merican Institute of Physics.