Transient beam loading effects and microwave instability are very important in ion synchrotrons. A simulation code Longitudinal Particle Tracking Code (LPTC) based on multi-particle tracking is developed to simulate the beam loading effects and the longitudinal beam instabilities in the booster ring (BRing) of the High Intensity heavy-ion Accelerator Facility (HIAF). A process of beam capture, acceleration, debunching, and the second capture is simulated with a reference ion beam of ${}^{78}$Kr${}^{19+}$. The simulation results show that the beam loading effects have major contribution to the beam behavior during the debunching stage and the second capture stage. A feed-forward system is suggested to compensate the beam loading effects, and the main parameters of the feed-forward system are given. The microwave instability of coasting ${}^{78}$Kr${}^{19+}$ beams is observed from the simulation results. The threshold of the microwave instability is also given. The development of self-bunching and methods to suppress the microwave instability in the BRing are discussed.

中文翻译：

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高强度重离子加速器设施的升压环中的束负载效应和微波不稳定性

在离子同步加速器中，瞬态束负载效应和微波不稳定性非常重要。开发了基于多粒子跟踪的模拟代码纵向粒子跟踪代码（LPTC），以模拟高强度重离子加速器设施（HIAF）的助推环（BRing）中的束负载效应和纵向束不稳定性。离子束捕获，加速，去束和第二次捕获的过程用${}^{78}$r${}^{19+}$。仿真结果表明，在去束阶段和第二捕获阶段，束载荷效应对束的行为有重要贡献。建议采用前馈系统来补偿光束载荷效应，并给出前馈系统的主要参数。滑行的微波不稳定性${}^{78}$r${}^{19+}$从模拟结果观察到光束。还给出了微波不稳定性的阈值。讨论了自聚集的发展以及抑制BRing中微波不稳定性的方法。