DIELECTRIC WALL LINAC INSULATOR FOR COMPACT (MEV) ELECTRON BEAM SOURCES

THERE ARE MULTIPLE APPLICATIONS FOR COMPACT PARTICLE ACCELERATORS, ESPECIALLY HIGH ENERGY [TENS OF MEV] AND HIGH CURRENT [KA] OUTPUT. GRADIENTS OF 10 TO 20 MV/M ARE POSSIBLE ONLY WITH RF ACCELERATORS. EXISTING LINEAR INDUCTION ACCELERATORS (LIAS) DO NOT OPERATE AT OVER 1 MV/M. RESEARCHERS ARE DEVELOPING AN INSULATOR TECHNOLOGY TO SUPPRESS AND ENHANCE VACUUM SURFACE FLASHOVER. THE TECHNOLOGY OPERATES UP TO THE GAP'S VACUUM BREAKDOWN STRENGTH 40 MV/M AT 100 NS LONG PULSES, WITH THE ESTIMATED THEORETICAL LIMIT IN THE 100S OF MV/M RANGE. THE TECHNOLOGY FOR USE IN LINEAR INDUCTION ACCELERATORS AND DIELECTRIC WALL INDUCTION LINACS IS BEING DEVELOPED. THE TECHNOLOGY HAS BEEN DEMONSTRATED FOR USE AS A VACUUM DIELECTRIC INSULATOR FOR GRADIENTS OF 40 MV/M AT PULSE LENGTH OF 100 TO 200 NSEC. THERE IS EVIDENCE THAT AT SHORTER PULSES (10 TO 50 NSEC OR SHORTER), THE BREAKDOWN STRENGTH INCREASES. DESIGN IS EXTENED TO INCLUDE A BETTER STRUCTURAL PROTECTION AND THE ABILITY TO BE DRIVEN WITH A HIGH CURRENT SINGLE PULSE SOURCE OR RF.