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Two-dimensional electromagnetic particle simulation is performed to investigate the profile relaxation from a magnetohydrodynamic (MHD) equilibrium to a kinetic one and the physical property of the kinetic equilibrium in the field-reversed configuration. The radial oscillation is excited in order to relax an excess energy in the MHD equilibrium. After this profile oscillation, the system spontaneously relaxes toward a kinetic equilibrium, in which the electron current profile becomes hollow as a result of the combined effects of the gradient-B drift near the field-null line and the EXB drift generated by the ion finite Larmor radius effect near the magnetic separatrix. On the other hand, the ion current profile becomes peaked due to the effect of the ion meandering orbit near the field-null line. The stability of the obtained kinetic equilibrium against the tilt mode is also studied by means of three-dimensional full electromagnetic particle simulation. It is found that the growth rate of the tilt instability in the case of the hollow current profile and high separatrix beta value is smaller than that in the case of the peaked current profile. [ABSTRACT FROM AUTHOR]

Investigates an electromagnetic instability in a magnetic neutral sheet by means of a two-and-one-half dimensional semi-implicit particle simulation code. Excitation of electromagnetic waves in a field null region after saturation of the lower hybrid drift waves; Characteristic properties of the instability.

A central theme of ``Complexity?? is the question of the creation of ordered structure in nature (self-organization). The assertion is made that self-organization is governed by three key processes, i.e., energy pumping, entropy expulsion and nonlinearity. Extensive efforts have been done to confirm this assertion through computer simulations of plasmas. A system exhibits markedly different features in self-organization, depending on whether the energy pumping is instantaneous or continuous, or whether the produced entropy is expulsed or reserved. The nonlinearity acts to bring a nonequilibrium state into a bifurcation, thus resulting in a new structure along with an anomalous entropy production. As a practical application of our grand view of self-organization a preferential generation of a dipole magnetic field is successfully demonstrated. [ABSTRACT FROM AUTHOR]

Discusses the simulation of a 'super' ion acoustic double layer. Illustration of self-organization in an open system, where fresh, constant flux of electrons is continuously supplied from the upstream boundary and distorted particles are discharged from the downstream boundary; Amplitude of the potential jump in super double layers.

Describes a computer simulation of a magnetohydrodynamic dynamo in a rapidly rotating spherical shell. Influence of resistivity on total magnetic energy and total kinetic energy of convection motion; Comparison of the two ways in which the magnetic field is organized.

Presents a type of self-organization where a system evolves intermittently and undergoes a self-adaptively local self maxima and minima of energy state. Numerical study of nonlinear interactions of twisting multiple flux tubes; Stimulation of the reconnection with a neighboring flux tube.

Investigates the formation of a wave-front pattern accompanied by an electrostatic ion-cyclotron instability driven by electrons drifting along a magnetic field. Use of two-and-half dimensional particle simulations; Appearance of a clear spatial wave-front pattern due to the instability; Description of the wave fronts.

Investigates a self-organization process of a magnetohydrodynamic (MHD) plasma with a finite thermal conductivity, by means of a three-dimensional MHD simulation. Smoothing of the perpendicular component of electric current and the nonuniformity of thermal pressure generated by driven reconnection.