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arXiv · 1910.01577

DC vacuum breakdown in an external magnetic field

S. Lebedynskyi·O. Karpenko·R. Kholodov·V. Baturin·Ia. Profatilova·N. Shipman·W. Wuensch
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Abstract

The subject of the present theoretical and experimental investigations is the effect of the external magnetic field induction on dark current and a possibility of breakdown. The generalization of the Fowler-Nordheim equation makes it possible to take into account the influence of a magnetic field parallel to the cathode surface on the field emission current. The reduction in the breakdown voltage due to the increment in electron-impact ionization was theoretical predicted. Experimentally shown that the presence of a magnetic field about a tenth as a large as the cutoff magnetic field [18] reduces the breakdown voltage by 10% to 20% for practically all cathodes no matter what their surface treatment.

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S. Lebedynskyi, O. Karpenko, R. Kholodov, V. Baturin, Ia. Profatilova, N. Shipman, W. Wuensch. 2019-09-30. DC vacuum breakdown in an external magnetic field. https://doi.org/10.1016/j.nima.2018.08.061

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