AN ENEXPENSIVE HIGH-CURRENT BETATRON

THE OBJECTIVE OF THIS PROJECT IS TO EMPLOY THE BETATRON PRINCIPLE TO PRODUCE AN INEXPENSIVE ELECTRON ACCELERATOR CAPABLE OF PRODUCING 20-50 MEV ELECTRONS WITH GOOD BEAM QUALITY AND HIGH-AVERAGE CURRENTS OF UP TO 5-50 MUA. IN CONVENTIONAL BETATRONS WHICH HAVE BEEN IN EXISTENCE FOR OVER 50 YEARS, EDDY-CURRENT LOSSES IN THE IRON LIMIT THE OPERATING FREQUENCY, THUS LIMITING THE MAXIMUM ENERGY AND CURRENT. THE USE OF HIGH-FREQUENCY MAGNETIC MATERIALS IS PLANNED SO THAT DRIVING FREQUENCIES OF UP TO A FEW KHZ MAY BE POSSIBLE, THEREBY PERMITTING SUBSTANTIALLY HIGHER AVERAGE CURRENTS. AS PROOF OF PRINCIPLE, UNDER PHASE I AN ENEXPENSEIVE ($0.2 MILLION), MODERATE-ENERGY (25 MEV), HIGH-AVERAGE-CURRENT (8 MUA) BETATRON WILL BE DESIGNED. THE FOLLOWING IS ALSO PLANNED: DETERMINATION OF THE ORBIT DYNAMICS AT HIGH REPETITION FREQUENCIES; DETERMINATION OF THE POLE SHAPES, POLE GAP, ORBIT RADIUS, AND ELECTRON-BEAM EMITTANCE; DESIGN OF THE INJECTION SYSTEM UTILIZING ORBIT CONTRACTION/EXPANSION COILS AND DETERMINATION OF AN OPTIMUM GUN SIZE; DESIGN OF THE EXTRACTION SYSTEM WITH ORBIT CONTRCTION/EXPANSION COILS AND A MAGNETIC SHUNT; AND DETERMINATION OF THE POWER SUPPLY REACTIVE POWER AND DISSIPATIVE POWER REQUIREMENTS. A DETAILED COST ESTIMATE WILL BE PREPARED WITH INFORMATION FROM VENDORS TO CONFIRM THAT THE COST IS MODERATE AND THAT THE HIGH FREQUENCY BETRATRON CAN BE A COMPETITOR TO RF LINACS IN THE COMMERCIAL MARKETPLACE.