Abstract:
Background To upgrade the beam energy of the CSNS-II linear accelerator from 80 MeV to 300 MeV, 324 MHz dual-spoke and 648 MHz elliptical superconducting cavities are introduced. Higher beam energy demands faster machine protection response to avoid damage from beam loss, requiring an advanced monitoring system.
Purpose This study develops a Differential Beam Current Monitor system to detect beam loss inside cavities by identifying downstream waveform distortion or disappearance relative to upstream, and triggering rapid protection.
Methods The system was developed based on a ZYNQ RFSoC development board. Taking advantage of the board’s 5 GSPS high sampling rate and the strong RF signal processing capability of its built-in RFDC module, the system achieves real-time acquisition of beam signals at both ends of the linear superconducting linac section.
Results Test results show that the system can accurately collect BCM waveforms at both ends of the superconducting section, effectively judge the differences between the two waveforms, and send protection signals in a timely manner.
Conclusions The system guarantees superconducting cavity safety, meets CSNS-II’s upgraded monitoring and protection needs.