SUPERCONDUCTING ACCELERATING RESONATOR FOR VERY LOW VELOCITY IONS

SUPERCONDUCTING HEAVY-ION BOOSTERS ARE LIMITED IN THEIR MASS RANGE BY THE VELOCITY ACCEPTANCE OF THE RESONATORS IN THEIR FIRST SECTIONS. A NEED HAS ARISEN TO DO NUCLEAR PHYSICS IN MASS RANGES INACCESSIBLE WITH EXISTING ACCELERATING STRUCTURES. THE END PRODUCT THAT WOULD RESULT FROM THIS RESEARCH IS AN ACCELERATING RESONATOR WITH AN UPPER MASS ACCEPTANCE 50% LARGER THAN EXISTING STRUCTURES. OUR EXPERIENCE, HOWEVER, INDICATES THAT SUCH A RESONATOR CANNOT BE DESIGNED BY SIMPLE EXTRAPOLATION OF EXISTING HIGHER BETA STRUCTURES BECAUSE OF THE INCREASING EFFECTS OF THE INTERACTIONS BETWEEN THE ELECTROMAGNETIC AND MECHANICAL MODES OF THE RESONATOR. UNDER THIS PHASE I GRANT, WE PROPOSE TO STUDY THESE INTERACTIONS AND FIND WAYS OF REDUCING THEM. THIS PROBLEM WILL BE APPROACHED FROM 3 DIRECTIONS: ELECTRONIC STABILIZATION (ACTIVE ELECTRONIC DAMPING OF MECHANICAL VIBRATIONS), ELECTROMAGNETIC DESIGN (SENSITIVITY OF RF FREQUENCY TO MECHANICAL DISPLACEMENT), AND MECHANICAL DESIGN (DESIGN OF INCREASED MECHANICAL STIFFNESS). THE RESULTS OF THIS RESEARCH COULD ALSO BE USEDTO RETROFIT AND UPGRADE EXISTING FACILITIES.