Lee, J.C. Chai, J.-S. Gad, Kh.M. Ghergherehchi, M. Ha, D.H. Kim, H.S. Namgoong, H. JACoW Publishing Geneva, Switzerland 978-3-95450-205-9 10.18429/JACoW-Cyclotrons2019-MOP030 English 100-102 MOP030 cavity coupling impedance cyclotron beam-loading Contribution to a conference proceedings 2020 2020-06 https://doi.org/10.18429/JACoW-Cyclotrons2019-MOP030 http://jacow.org/cyclotrons2019/papers/mop030.pdf The 10 MeV cyclotron was designed for next version in Sungkyunkwan University, after the SKKUCY-9 had developed for medical application for PET. The RF cavity, which generates the electric field in cyclotron, was designed based on a half-wavelength resonator and optimized to improve the unloaded quality factor (Q₀). The design specifications of RF cavity were resonance frequency 83.2 MHz, Q₀ 5830 and Dee voltage 40 kV with geometrical values resonator length 560 mm, Dee angle 35° and Stem radius 16 mm. The RF cavity of the SKKUCY-10 was fabricated and installed inside the electromagnet, and RF characteristics were measured with a network analyzer. The RF coupling coefficient and characteristic impedance for desired condition were selected at 1.08 and 52 ’, respectively. The RF coupling coefficient and characteristic impedance were measured 0.8-1.2, 52-49 ’ according to temperature as 15-21°C. The power coupler was checked for optimization of RF coupling coefficient and characteristic impedance, and the results show good agreement with simulated and measured data.