基于超导器的连续波运行的高流强质子/氘束被越来越多的大科学装置所采用。在流强低于10 mA情况下, 用于加速低β段粒子的超导腔的高阶模影响基本可以忽略, 但是对于加速百mA强流的低β超导腔, 其高阶模损耗情况有待研究。近期北京大学设计并加工了一支β=0.09、运行频率162.5 MHz的超导半波长谐振腔, 用于研究非相对论低β超导半波长谐振腔加速100 mA强流质子束时可能涉及到的关键物理问题。重点研究了这支半波长谐振腔内部高阶模损耗的问题, 用时域和频域两种方法分别计算了腔的高阶模损失因子, 同时计算了考虑加工误差下腔内发生高阶模共振激发的概率。

There is presently a growing demand for CW high current proton and deuteron linear accelerators based on superconducting technology to better support various fields of science. Up to now, high order modes (HOMs) studies induced by ion beams with current higher than 10 mA and even 100 mA accelerated by low β non-elliptical superconducting RF (SRF) cavities are very few. Peking University has recently designed and fabricated a β=0.09, 162.5 MHz half wave resonator(HWR) cavity to study the key physics problems in low beta HWR cavity accelerating beam with current of about 100 mA. This paper focuses on the study of the HOM-induced power in this cavity. The incoherent beam energy loss induced by 100 mA beam through the HWR SRF cavity were obtained by both time domain solver and frequency domain eigenmodes spectrum method. The possibility of coherent excitation of this cavity considering manufacture errors was also analysed.