Yamauchi, H. Masuoka, M. JACoW Publishing Geneva, Switzerland 2226-0366 978-3-95450-215-8 10.18429/JACoW-LINAC2022-MOPORI12 English 255-257 cavity rfq MMI operation neutron Contribution to a conference proceedings 2022 2022-09 https://doi.org/10.18429/JACoW-LINAC2022-MOPORI12 https://jacow.org/linac2022/papers/mopori12.pdf TIME Co. developed a new 4-vane RFQ structure that can be used for a very high-duty factor operation. We eliminated the tuners to flatten the field distribution. The tuners increase RF contacts which may trigger unex-pected local heat spots and subsequent discharges. In addition, we hollowed out the entire vane to achieve large cooling water channels. A high-power test showed that the commissioning was completed within one day. We could input a nominal RF power without experienc-ing almost any discharge. The applied duty factor was 5 % at the 200 MHz resonant frequency, and the meas-ured frequency shift was not detected.