Dynamics of a charged particle in a linearly polarized traveling wave: applications to laser-matter interaction at very high intensities

Summary form only given. In order to understand laser-plasma interaction at intensities above 10/sup 18/ W/cm, the stability of the single particle motion in the fields of ultra-high-intensity laser waves has been studied. A 4-potential perturbation is considered to describe the influence of the plasma collective response and other waves, in order to discuss the validity of the adiabatic approximation.