Superconducting radio-frequency cavity fault classification using machine learning at Jefferson Laboratory
This work addresses the laborious and time-consuming manual analysis of cavity faults in particle accelerators, enabling more efficient trend analysis and mitigation deployment, though it is incremental as it applies existing ML methods to a specific domain problem.
The researchers tackled the problem of manually labeling superconducting radio-frequency cavity faults at Jefferson Lab by developing machine learning models for near real-time identification and classification, achieving accuracies of 84.9% for cavity identification and 78.2% for fault classification.
We report on the development of machine learning models for classifying C100 superconducting radio-frequency (SRF) cavity faults in the Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Lab. CEBAF is a continuous-wave recirculating linac utilizing 418 SRF cavities to accelerate electrons up to 12 GeV through 5-passes. Of these, 96 cavities (12 cryomodules) are designed with a digital low-level RF system configured such that a cavity fault triggers waveform recordings of 17 RF signals for each of the 8 cavities in the cryomodule. Subject matter experts (SME) are able to analyze the collected time-series data and identify which of the eight cavities faulted first and classify the type of fault. This information is used to find trends and strategically deploy mitigations to problematic cryomodules. However manually labeling the data is laborious and time-consuming. By leveraging machine learning, near real-time (rather than post-mortem) identification of the offending cavity and classification of the fault type has been implemented. We discuss performance of the ML models during a recent physics run. Results show the cavity identification and fault classification models have accuracies of 84.9% and 78.2%, respectively.