Numerical Simulation of 2-D Density Cavitons in a Two-Fluid Electromagnetic Plasma

This article presents a 2-D generalization of the 1-D simulation (J. Phys. Soc. Jpn. vol. 90, 114501, 2021) of density cavitons formed in a two-fluid plasma induced by a Gaussian perturbed perpendicular magnetic field. It is shown that the mechanism for caviton formation employed before can also be used to generate the corresponding higher-dimensional structures. Here, the two-fluid electron-ion model is numerically integrated by means of a finite volume numerical scheme to evolve the system of equations in time over several ion plasma periods. Additionally, it demonstrates how the long-duration stability of the numerical process can be maintained by including a mechanism for satisfying the divergence constraints in Maxwell’s equations. Analysis of the dominant wave modes undertaken by 2-D FFT analysis provides useful information on how the caviton structures relate to the linear modes.