Publications

Digest of Technical Papers-IEEE International Pulsed Power Conference

Joseph, Nathan R.; Savage, Mark E.; Stephens, Jacob C.; Lott, John A.; Lewis, B.A.; Thomas, Rayburn D.; Torres, Matthew T.; Holman, Edward G.

The Sandia National Laboratories SPHINX accelerator is used to study the response of electronics to pulsed x-ray and electron environments. The system consists of a Marx generator and an oil-insulated pulse-forming line with self-closing oil switches. SPHINX has a peak load voltage of 2 MV and an adjustable pulse width ranging from 3 to 10 ns. The previous pulsed-power system had reliability and triggering issues with the Marx generator and subsequent undesired variations in voltage output. SPHINX was upgraded to a new Marx-generator system that has solved many of the voltage-output fluctuation and timing issues. The new Marx generator uses recently developed low-inductance 100-kV capacitors and 200-kV spark-gap switches. This paper provides an overview of SPHINX while capturing in detail the design, characterization, and comparative performance of the new Marx generator.

Struve, Kenneth W.; Thomas, Rayburn D.; Joseph, Nathan R.; Harper-Slaboszewicz, V.H.

Abstract not provided.

Oliver, Bryan V.; Thomas, Rayburn D.

Abstract not provided.

Digest of Technical Papers-IEEE International Pulsed Power Conference

VanDevender, J.P.; Seidel, David B.; Mikkelson, Kenneth A.; Thomas, Rayburn D.; Peyton, B.P.; Harper-Slaboszewicz, V.H.; McBride, Ryan D.; Cuneo, M.E.; Schneider, Larry X.

A newly invented, multi-megampere inverse diode converts the currents in many electron beams to current in a single Magnetically Insulated Transmission Line (MITL) for driving a common load. Electrons are injected through a transparent anode, cross a vacuum gap, and are absorbed in the cathode of the inverse diode. The cathode current returns to the anode through a load and generates electric and magnetic fields in the anode-cathode gap. Counter streaming electron flow is prevented by self-magnetic insulation in most of the inverse diode and by self-electrostatic insulation where the magnetic field is insufficient. Two-dimensional simulations with a 40 MA, 4 MeV, 40 ns electron beam at 3.5 kA/cm 2 current density, 5 degree beam divergence, and up to 60 degree injection angle show 85% of the injected electron beam current is captured and fed into the MITL. Exploratory experiments with a 2.5 MA, 2.8 MeV, 40 ns electron beam at 2 kA/cm 2at injection normal to the anode gave 70+/-10% collection efficiency in an unoptimized inverse diode. The inverse diode appears to have the potential of coupling multiple pulsed power modules into a common load at rates of change of current ∼1.6× 10 15 A/s required for a fusion energy device called the Plasma Power Station with a Quasi Spherical Direct Drive fusion target. © 2011 IEEE.

Slutz, Stephen A.; Sefkow, Adam B.; Matzen, M.K.; Thomas, Rayburn D.; Cuneo, M.E.; Vesey, Roger A.; Herrmann, Mark H.; Sinars, Daniel S.; Seidel, David B.; Schneider, Larry X.; Mikkelson, Kenneth A.; Harper-Slaboszewicz, V.H.

Abstract not provided.

Seidel, David B.; Mikkelson, Kenneth A.; Thomas, Rayburn D.; Harper-Slaboszewicz, V.H.; Schneider, Larry X.

Abstract not provided.

Savage, Mark E.; Leeper, Ramon J.; Leifeste, Gordon T.; Lemke, Raymond W.; Long, Finis W.; Lopez, Mike R.; Matzen, M.K.; McKee, George R.; Stoltzfus, Brian S.; Struve, Kenneth W.; Atherton, B.W.; Stygar, William A.; Thomas, Rayburn D.; Woodworth, Joseph R.; Bliss, David E.; Cuneo, M.E.; Davis, Jean-Paul D.; Hall, Clint A.; Herrmann, Mark H.; Jones, Michael J.; Knudson, Marcus D.

Abstract not provided.