MODULATOR SYSTEMS FOR HEAVY ION FUSION ACCELERATORS

THIS PROJECT EMPLOYS A TWO-PART DESIGN STUDY FOR HIGH CURRENT, HEAVY ION, RECIRCULATING INDUCTION ACCELERATORS FORINERTIAL FUSION INVOLVING: (1) MODULATOR CIRCUIT DESIGN FOR RECIRCULATING ACCELERATORS, BASED PARTICULARLY ON RECENT ADVANCES IN HIGH POWER SWITCH TECHNOLOGY, AND (2) OPTIMUM RECIRCULATOR DESIGN TO MAKE THE BEST USE OF ADVANCES IN THE SWITCHES AND CIRCUITS. RECENT DOE STUDIES HAVE SHOWN HEAVY ION ACCELERATORS TO BE THE DRIVER OF CHOICE FOR INERTIAL FUSION. IN ADDITION, STUDIES OF RECIRCULATING LINACS INDICATE LARGE POTENTIAL COST SAVINGS. HOWEVER, A RECIRCULATING LINAC PLACES SEVERE DEMANDS ON THE MODULATORS REQUIRED TO POWER THE INDUCTION CAVITIES. THE MODULATORS MUST PRODUCE A TRAIN OF PULSES EQUAL IN NUMBER TO THE NUMBEROF BEAM RECIRCULATIONS, TO A BURST FREQUENCY UP TO 50 KHZ. MOREOVER, THE MOST EFFICIENT DESIGNS REQUIRE THE PULSE DURATION TO VARY DURING THE BURST. CONVENTIONAL MODULATORS BASED ON THYRATRONS OR SPARK GAPS REQUIRE LARGE NUMBERS OF SEPARATE CIRCUITS AND ARE THEREFORE COSTLY. RECENT ADVANCESIN SOLID-STATE SWITCHES INDICATE THAT EXCELLENT PULSE-SHAPE FLEXIBILITY AT HIGH VOLTAGE MAY BE ATTAINABLE. SUCH DEVICESCAN ENHANCE THE SUITABILITY OF RECIRCULATING LINACS AND HOLD PROMISE FOR CONVENTIONAL LINACS. THE PHASE I WORK INCLUDES AN INTEGRATED DESIGN STUDY OF MODULATOR CIRCUITS, CANDIDATE SWITCHES, AND SYSTEM DESIGN, THE LATTER BASED ON ARECENTLY DEVELOPED PROGRAM. PHASE II IS TO INVOLVE COLLABORATION WITH A DEVICE DEVELOPER CHOSEN AS A RESULT OF THE PHASE I EFFORT.