Magnetoparametric instabilities in the Crab Nebula: II.
Abstract
Results of a previous linear analysis of parametric instabilities of electromagnetic waves in a onefluid coldplasma model with immobile ions are extended by relaxing the assumption of immobile ions, treating the ion motion in a fully relativistic way, and examining the nonlinear evolution of the magnetoparametric instabilities computed in the linearized analysis. Two types of twofluid model are considered: electronproton and electronpositron. A dispersion relation is derived which describes the evolution of mixed electromagnetic and spacecharge perturbations to a strong circularly polarized electromagnetic wave propagating along a magnetostatic field in a twofluid cold plasma, assuming that the perturbations propagate parallel to the driving field. The dispersion relation is shown to result in a twelfthorder polynomial, which is investigated for instabilities. The nonlinear development of these instabilities is analyzed by means of a numerical simulation, the linear and nonlinear analyses are compared, and the results are discussed in the context of the Crab Nebula where applicable. The twofluid results are then extensively compared with those for the onefluid model.
 Publication:

Astronomy and Astrophysics
 Pub Date:
 May 1978
 Bibcode:
 1978A&A....66..139S
 Keywords:

 Cold Plasmas;
 Crab Nebula;
 Magnetohydrodynamic Stability;
 PlasmaElectromagnetic Interaction;
 Wave Propagation;
 Ion Motion;
 Magnetic Fields;
 Nonlinear Equations;
 Relativistic Particles;
 Two Fluid Models;
 Astrophysics;
 Crab Nebula:Instabilities;
 Plasma: Wave Propagation