Design and primary test of full scale cavity of cyciae-100

The engineering of the RF cavity for cyclotron concerns several aspects, including the vacuum, cooling, mechanical support etc. Sometimes it is even more complex than RF design itself. Given the space limit in a compact cyclotron, to have a voltage distribution of 60kV in central orbit and 120kV for outer orbit, a double stem double gap lambda by 2 cavity has been designed for CYCIAE-100[1]. The RF resonance of the cavity is simulated [1] by finite integral codes, while the thermal analysis and mechanical tolerance is studied using other approaches[2-3]. The mechanical design and fabrications is then carried out under these directions, resulting in a full scale testing cavity. The simulations and mechanical design will be reported in this paper, followed with low level measurement results of quality factor, shunt impedance curve along accelerating gap etc. After surface polishing, the measurement yields an unloaded Q value of 9300, which matches well with the simulation with a neglectable difference of several hundreds. The high power test of the cavity and will be presented in a separate paper of this conference.