Anthony J. Marolda

My second job as a physicist was with E.G.&G. Inc. It involved working on high voltage, pulse power electron beam acellerators for the simulation of nuclear weapons effects. I also had to write quarterly reports on the results of the research for the Atomic Energy Commission. The photo on the top right of the page is from an experiment I did. It shows two metal spheres, each one meter in diameter. They were separated by one meter. The electrical breakdown between the spheres resulted from a two megavolt (million volts) pulse with a risetime of only 5 nanoseconds (billionths of a second) and a duration of 50 nanoseconds. We were testing the performance of the pulse power generator to ultimately be used to create fast rise time, short duration pulses of x rays.

The photo top left is me in 1967, in the laboratory, standing in front of the experimental arrangement.

One aspect of the two megavolt pulse generator was the development of a fast rise time, high voltage switch. We had been using a solid state material for the switch. It had to be replaced after each shot. I thought about using a high power ruby laser to trigger the switch in a liquid dielectric. This would be a self-healing approach. So I conducted tests to see if it would work . It did. The experimental results were published in "The Journal of Quantum Electronics" with the title, "Laser Triggered Switching in a Liquid Dielectric", August, 1968.
Surprisingly, while working as a physicist, I had to do a considerable amount of writing. My first job was with High Voltage Engineering Corporation. My assignment was to improve the performance of a Duoplasmatron ion source used with a VandeGraff particle accelerator. Each quarter, I had to write a report on our results, and present it to the Research Committee.

In the course of that work, I became very familiar with the field of Plasma Physics. As a result, I developed an idea for a new type of ion source. I wrote a detailed report describing the idea and submitted it to the head of R&D. He liked it and recommended that the company patent the device. The patent attorney asked me to consider other uses that could be submitted as claims. I developed an addendum to the report that showed how the device could be modified for use as an ion propulsion engine for space applications. When the patent was granted, the Patent Office included that claim. The title of the patent is "Apparatus for Generating a High Density Plasma".The patent number is 3,321,919. It was published on May 30, 1967.
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of the laser article.