Sakamoto, N. Hara, H. Kako, E. Kamigaito, O. Nakai, H. Okihira, K. Okuno, H. Ozeki, K. Sennyu, K. Suda, K. Umemori, K. Watanabe, Y. Yamada, K. Yanagisawa, T. JACoW Geneva, Switzerland 978-3-95450-178-6 10.18429/JACoW-SRF2015-WEBA06 English 976-981 WEBA06 linac cryomodule beam-loading simulation ion Contribution to a conference proceedings 2015 2015-12 http://dx.doi.org/10.18429/JACoW-SRF2015-WEBA06 http://srf2015.vrws.de/papers/weba06.pdf Recently we proposed a new project aimed at intensity upgrade of uranium beams of RIKEN RIBF. In this new project, construction of a superconducting linac is planned replacing the injector cyclotron so called RRC. The RIKEN superconducting linac consists of 14 cryomodules each of which contains four quarter-wave-resonators (QWRs) in each. The QWR operates at an rf frequency of 73 MHz in the continuous wave mode with beta as low as 0.055-1.008. A coaxial probe-type RF fundamental power-coupler which transmits RF power of several kW will be utilized for beam loading of 1.3 kW/resonator at the maximum with Qext of several x10⁶. Tuning of the resonant frequency will be realized with a mechanical tuner pressing the resonator wall in the direction parallel to the beam. This year, we started a development of a test cryomodule with SC-QWRs. In this paper, design studies for a SC-QWR and its cryomodule, e.g., QWR, coupler, and, tuner will be presented together with a construction schedule of the prototype. Prototyping of a superconducting cavity and its test cryomodule was funded by ImPACT Program of Council for Science, Technology and Innovation (Cabinet Office, Government of Japan).