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تسجيل مستخدم جديدA necessary condition for perpendicular electric field control in magnetized plasmas
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The electrostatic model proposed by Poulos [Phys. Plasmas (2019), $mathbf{26}$, 022104] to describe the electric potential distribution across and along a magnetized plasma column is used to shed light onto the ability to control perpendicular electric fields. The effective electrical connection between facing end-electrodes is shown to be conditioned upon the smallness of a dimensionless parameter $tau$ function of the plasma column aspect ratio and the square root of the conductivity ratio $sigma_perp/sigma_{parallel}$. The analysis of a selected set of past end-electrodes biasing experiments confirms that this parameter is small in experiments that have successfully demonstrated perpendicular electric field tailoring. On the other hand, this parameter is $mathcal{O}(1)$ in experiments that failed to demonstrate control, pointing to an excessively large ion-neutral collision frequency. A better understanding of the various contributions to $sigma_perp$ is needed to gain further insights into end-biasing experimental results.
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