A self-consistent model of the magnetosphere with centrifugal wind, II

Abstract

In order to construct an axisymmetric model of magnetospheres with centrifugal wind, especially of the type II magnetosphere in Paper I (Shibata and Kaburaki, 1984), we present a numerical iterative scheme, in which a tenuous plasma with conspicuous trans-field motion are treated self-consistently with the electromagnetic field. Since the characteristic equations of the flow are solved, we are free from numerical diffusion terms obscuring the cause of the trans-field motion. The obtained properties of type II magnetosphere are as follows. (1) Plasma particles in fact flow out across the closed magnetic field lines. (2) The centrifugal force is exerted powerfully on the positive particles to form a disk-like structure, and the strong electric force makes the negative particles drift to the disk. (3) There appears the electric field parallel to the magnetic field,E _‖, which is shown to be necessary for the steady wind to exist. Within the range of the model-parameters selected in this study we find two reasons for the appearance ofE _‖: (1) plasma density decreases owing to the centrifugal acceleration, and it becomes insufficient to shieldE _‖; (2) the plasma with large inertia moves so as to reduce the charge separation, which would be necessary to shieldE _‖.

The notation and definitions are the same as in Paper I.