Coherent production of energetic electrons in anomalous reflection and absorption of intense laser light

The rate at which electrons are transported from the body to the nonthermal tail of the distribution function in the nonlinear stage of reflective and absorptive parametric instabilities is computed. The calculation is performed by conserving energy and momentum between waves and particles in the nonlinear regime. For the case of reflection, the reflection coefficient and energy flux of nonthermal particles are computed. It is found that the principal effect of the trapped electrons is to increase the density gradient length scale by as much as a factor of twenty five, at given reflection coefficient. For absorption, the rate of production of energetic particles is found. Also, the transport of energetic particles into the core of a laser fusion plasma is examined.