DIELECTRIC THEORY OF COLLISIONAL ABSORPTION IN INTENSE LASER FIELDS

Collisional absorption of superintense laser pulses in dense plasmas c an be described by the classical linear dielectric theory in a wide ra nge of parameters. For electron oscillation velocities largely exceedi ng their thermal motion a linear oscillator model is presented and nea rly exact solutions in terms of Anger functions are given for the time -averaged electron-ion collision frequency. A possible extension of th e dielectric theory into higher density and/or lower temperature regio ns is indicated and the need for time-dependent collision frequencies is stressed.