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Title: Vacuum arc cathode spot motion in oblique magnetic fields: An interpretation of the Robson experiment

Abstract

A model was developed of vacuum arc cathode spot motion in a magnetic field that obliquely intercepts the cathode surface. The model takes into account a force under an electric field caused by retrograde spot motion across the normal component of the magnetic field, producing a drift velocity component in the direction of the acute angle between the magnetic field and the cathode surface. The relationship between velocity of the retrograde direction and drift velocity of the cathode spot motion to the acute angle was developed. The dependencies of the drift angle θ on the acute angle φ, magnetic field strength B, and arc current I were calculated. It was found that the calculated θ increased with φ, B, and I in accordance with Robson's measurements.

Authors:
 [1]
  1. Electrical Discharge and Plasma Laboratory, School of Electrical Engineering, Fleischman Faculty of Engineering, Tel Aviv University, P.O.B. 39040, Tel Aviv 69978 (Israel)
Publication Date:
OSTI Identifier:
22599870
Resource Type:
Journal Article
Resource Relation:
Journal Name: Physics of Plasmas; Journal Volume: 23; Journal Issue: 9; Other Information: (c) 2016 Author(s); Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
70 PLASMA PHYSICS AND FUSION TECHNOLOGY; CATHODES; ELECTRIC FIELDS; MAGNETIC FIELDS; SURFACES; VELOCITY

Citation Formats

Beilis, I. I. Vacuum arc cathode spot motion in oblique magnetic fields: An interpretation of the Robson experiment. United States: N. p., 2016. Web. doi:10.1063/1.4961920.
Beilis, I. I. Vacuum arc cathode spot motion in oblique magnetic fields: An interpretation of the Robson experiment. United States. doi:10.1063/1.4961920.
Beilis, I. I. 2016. "Vacuum arc cathode spot motion in oblique magnetic fields: An interpretation of the Robson experiment". United States. doi:10.1063/1.4961920.
@article{osti_22599870,
title = {Vacuum arc cathode spot motion in oblique magnetic fields: An interpretation of the Robson experiment},
author = {Beilis, I. I.},
abstractNote = {A model was developed of vacuum arc cathode spot motion in a magnetic field that obliquely intercepts the cathode surface. The model takes into account a force under an electric field caused by retrograde spot motion across the normal component of the magnetic field, producing a drift velocity component in the direction of the acute angle between the magnetic field and the cathode surface. The relationship between velocity of the retrograde direction and drift velocity of the cathode spot motion to the acute angle was developed. The dependencies of the drift angle θ on the acute angle φ, magnetic field strength B, and arc current I were calculated. It was found that the calculated θ increased with φ, B, and I in accordance with Robson's measurements.},
doi = {10.1063/1.4961920},
journal = {Physics of Plasmas},
number = 9,
volume = 23,
place = {United States},
year = 2016,
month = 9
}
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