Relativistic wave-induced splitting of the Langmuir mode in a magnetized plasma.
A relativistic effect that occurs in a magnetized plasma irradiated by a circularly polarized wave is identified and analyzed: the usual plasma frequency associated with longitudinal oscillations splits into two new frequencies. We set up a Hamiltonian description of the plasma dynamic in order to identify this effect that results from the coupling between the plasma oscillation and the transverse circular motion driven by both the magnetic and wave fields. Within the small oscillations approximation, we compute for right- and left-handed polarization the two characteristics frequencies of the electron oscillations as functions of the field and wave parameters. We also describe the electron trajectories in the wave, magnetic, and restoring plasma fields. This new class of oscillations is rotational and therefore radiate suggesting a method for the diagnostics of strong static magnetic field in laser-plasma experiments.
Robiche
J
J
Laboratoire de Physique et Technologie des Plasmas, Ecole Polytechnique, Palaiseau, 91 128 Cedex, France. robiche@greco2.polytechnique.fr
Rax
J M
JM