TUOBC  —  PPHIB: Pulsed Power & High-intensity Beams/Induction Linacs   (26-Jun-07   12:00—12:30)

Chair: D. R. Welch, Voss Scientific, Albuquerque, New Mexico

Paper Title Page
TUOBC01 Synchronizable High Voltage Pulser with Laser-Photocathode Trigger 862
 
  • P. Chen
  • M. Lundquist, R. Yi, D. Yu
    DULY Research Inc., Rancho Palos Verdes, California
 
  Funding: Work supported by DOE SBIR grant no. DE-FG02-03ER83878.

High-gradient electron guns can suppress space-charge induced transverse emittance growth when the electron beam is still in the low-energy injection stage. A synchronizable, high-voltage pulser can be used to power up a high-gradient gun. We propose to build a 200 kV pulser using a special trigger that utilizes a laser-photocathode sub-system. A laser trigger beam will first energize a spark gap, and then provide a second trigger signal from a photocathode using its leftover energy, to further close the gap. This system will not only raise the utilization efficiency of the laser beam energy, but also enhance the reliability of the trigger circuit. Our preliminary analysis shows that the proposed system will significantly improve the performance of the laser trigger pulse with the jitter on the order of hundreds of picoseconds. It is expected that the pulser can be used in the applications of high gradient guns as well as in other devices that need high precision trigger such as short pulse lasers, streak cameras, impulse radiating antennas, etc.

 
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TUOBC02 A New Type High Voltage Fast Rise/Fall Time Solid State Marx Pulse Modulator 865
 
  • R. L. Cassel
  • S. Hitchcock
    Stangenes Industries, Palo Alto, California
 
  A new type of solid state Marx modulator developed by Stangenes Industries has the capability of producing high voltage pulses with fast rise and fall time at high repetition rates. In addition it has the ability to produce dynamically flexible output amplitude and pulse width. The pulse modulator was developed for the Fermi Labs Tevatron Electron Lens Tune Compensation System. It can produce a 14kV pulse with 200 nanosecond rise time and 600 nanosecond full pulse width at a 25 kilohertz repetition rate. It has no overshot or reverse voltage, making it ideal for beam bunch manipulation. It is designed to operate into a 200 pfd, 800 Ω load. This design permits all of the sources of power including the 1kV charging power supply to be connected at the grounded end of the pulser. A second generation pulser is under development to operate at above 50 kHz repetition rate with an arbitrary voltage waveform and faster rise/fall time. The pulser can accommodate load arcing and incorporates built in redundancy to insure high availability. The paper delineates the unique design of the modulator and its performance.  
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