A SUPERCONDUCTING MAGNET FOR A QUASI-OPTICAL GYROTRON

THE QUASI-OPTICAL GYROTRON, AN ALTERNATIVE TO THE MORE CONVENTIONAL MICROWAVE CAVITY GYROTRON, MAY HAVE ADVANTAGES IN ACHIEVING THE PERFORMANCE LEVELS OF FREQUENCY AND POWER IDENTIFIED FOR FUTURE PLASMA HEATING APPLICATIONS. THE SHEET BEAM GUN REQUIRED FOR THE HIGH POWER QUASI-OPTICAL GYROTRON IS ALREADY WELL ALONG IN DEVELOPMENT. IT IS TIMELY TO STUDY THE DETAILED MAGNET IMPLICATIONS OF THE QUASI-OPTICAL GYROTRON AND TO BUILD SUCH A MAGNET AS PART OF A QUASI-OPTICAL GYROTRON TEST FACILITY. IN PHASE I STUDIES WILL BE MADE OF THE RELATION BETWEEN GYROTRON PERFORMANCE AND MAGNET PARAMETERS, INCLUDING SIZE OF CROSS BORE, AXIAL FIELD UNIFORMITY, AND OVER-ALL MAGNET SIZE. MICROWAVE HEATING IN THE CRYOSTAT SHIELDS WILL BE ESTIMATED,AND A PRELIMINARY MAGNET DESIGN WILL BE PREPARED. THE MAGNET WILL INCORPORATE NB3SN SECTIONS, AND THE DESIGN RESTRICTIONS OF CURRENT DENSITY, STRESS, AND PROTECTION WILLBE INCLUDED IN THE PRELIMINARY DESIGNS. PHASE I WILL RESULTIN A MAGNET SPECIFICATION AND SUFFICIENT DESIGN DETAIL TO FORM THE BASIS FOR A DECISION TO PROCEED WITH MAGNET CONSTRUCTION IN PHASE II.