Electron Gun Technology
Abstract
The first gun developed was the plasma cathode electron gun. The electron source in this device is a plasma generated within a low-voltage, hollow-cathode discharge; a thermionic emitter is not required. Electrons extracted from the plasma pass through a triode-type control grid structure and are accelerated to high energies in a plasma-free region prior to emerging from the gun through a thin foil window. The device, which is capable of both pulsed and cw operation, is characterized by durability, low cost, low power consumption, small size, and fast turn-on in comparison to thermionic e-guns. Most recent efforts on the program have been directed to developing the ion plasma electon gun. Potential advantages for this gun include high-voltage operation (>400 kV), high output current density (5 to 10 A/sq. cm. pulsed), pulsed and cw operation, monoenergetic e-beam, dc high voltage power supply for repetitively pulsed operation, and no control electronics floating at high voltage. In this gun, a low-pressure, thin-wire discharge produces ions which are accelerated to collide with the cathode. Secondary electrons are emitted at the cathode and are accelerated by the same high voltage and extracted through a foil window. Experimental results with a 4 cm x 40 cm aperture test device have demonstrated the concept of the ion plasma e-gun.
Document Details
- Document Type
- Technical Report
- Publication Date
- Dec 20, 1976
- Accession Number
- ADA034170
Entities
People
- Gilmore S. Dunning
- William M. Clark Jr.
Organizations
- HRL Laboratories