title: Two dimensional triangulation of breakdown in a high voltage coaxial gap.
abstract: We describe a technique by which magnetic field probes are used to triangulate the exact position of breakdown in a high voltage coaxial vacuum gap. An array of three probes is placed near the plane of the gap with each probe at 90° intervals around the outer (anode) electrode. These probes measure the azimuthal component of the magnetic field and are all at the same radial distance from the cylindrical axis. Using the peak magnetic field values measured by each probe, the current carried by the breakdown channel, and Ampères law we can calculate the distance away from each probe that the breakdown occurred. These calculated distances are then used to draw three circles each centered at the centers of the corresponding magnetic probes. The common intersection of these three circles then gives the predicted azimuthal location of the center of the breakdown channel. Test results first gathered on the coaxial gap breakdown device (240 A, 25 kV, 150 ns) at the University of California San Diego and then on COBRA (1 MA, 1 MV, 100 ns) at Cornell University indicate that this technique is relatively accurate and scales between these two devices.
authors.affiliation: Center for Energy Research, University of California San Diego, San Diego, California 92093, USA.
authors.forename: S W
authors.initials: SW
authors.lastname: Cordaro
authors.affiliation: Center for Energy Research, University of California San Diego, San Diego, California 92093, USA.
authors.forename: S C
authors.initials: SC
authors.lastname: Bott-Suzuki
authors.affiliation: Center for Energy Research, University of California San Diego, San Diego, California 92093, USA.
authors.forename: L S Caballero
authors.initials: LS
authors.lastname: Bendixsen
authors.affiliation: Laboratory for Plasma Studies, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Levon
authors.initials: L
authors.lastname: Atoyan
authors.affiliation: Laboratory for Plasma Studies, Cornell University, Ithaca, New York 14853, USA.
authors.forename: Tom
authors.initials: T
authors.lastname: Byvank
authors.affiliation: Laboratory for Plasma Studies, Cornell University, Ithaca, New York 14853, USA.
authors.forename: William
authors.initials: W
authors.lastname: Potter
authors.affiliation: Laboratory for Plasma Studies, Cornell University, Ithaca, New York 14853, USA.
authors.forename: B R
authors.initials: BR
authors.lastname: Kusse
authors.affiliation: Laboratory for Plasma Studies, Cornell University, Ithaca, New York 14853, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Greenly