RF ACCELERATOR TECHNOLOGY FOR VERY HIGH POWERS

RADIATION PROCESSING, PARTICULARLY TECHNIQUES FOR RADIATION ENHANCED SHELF LIFE OF FOODS, ARE IMPORTANT POSSIBLE APPLICATIONS OF ELECTRON ACCELERATORS. IN ORDER FOR THIS TOBECOME ECONOMICALLY ATTRACTIVE, AN ELECTRON ACCELERATOR OF 5MEV MAXIMUM ENERGY WITH AN AVERAGE BEAM POWER OF 500 KW MUSTBE DEVELOPED. LOW FREQUENCY RF LINACS (LESS THAN 300 MHZ.) ARE VERY ATTRACTIVE CANDIDATES FOR THIS APPLICATION. IN THIS WORK, WE PROPOSE TO BUILD A 100 KV MODULE OF SUCH AN ACCELERATOR WITH REALISTIC BEAM LOADING AND AN INEXPENSIVE 200 MHZ. POWER TRIODE AMPLIFIER IN ORDER TO TEST THE CAPABILITIES THIS CLASS OF MACHINE. TECHNIQUES ARE PROPOSEDWHICH WILL ALLOW THE MAJORITY OF THE 1 METER CAVITIES TO BE INSULATED WITH ATMOSPHERIC PRESSURE GAS (SULPHUR HEXAFLUORIDE), RESULTING IN SIGNIFICANT SIMPLIFICATIONS TO THE DESIGN AND COOLING OF SUCH ACCELERATORS. THE MODULE WHICH WILL BE DEVELOPED WILL ALSO BE TESTED IN VACUUM FOR COMPARISON, AND TO ESTIMATE THE HEATING OF THE STRUCTURE IN VACUUM. THE MODULAR APPROACH WHICH WE ARE USING SIGNIFICANTLY INCREASES THE FAULT TOLERANCE AND OVERALL RELIABILITY OF THE ACCELERATOR. IF SUCCESSFUL, THE COSTS OFHIGH POWER RF ACCELERATORS WILL BE SIGNIFICANTLY REDUCED, AND THE POWER LEVELS OF THESE ACCELERATORS WILL BE SIGNIFICANTLY INCREASED.