Influence of axial field is developed only in the final stage of implosion when the magnitudes of azimuthal and axial fields became approximately equal.
The application of an axial magnetic field is the well-known method for stabilizing plasma z-pinch implosions.
This measured lack of a coherent plasma shell prior to the radial implosion of the array motivated the use of increased wire number.
This should be adequate for the cryogenic implosion experiments planned for the system.
However, in the low density foam region, the radiation energy can be confined and the implosion non-uniformity is smoothed.
Of course, such an implosion nonuniformity consists of both the velocity and position per turbations of the shell in a real implosion.
In order to regulate the implosion of shells by usual thermal ablation-compression, the selection of velocities around 4.5 x 107 cm s-1 is important.
The array then adopts a more azimuthally symmetric implosion.
