ISBN 9783843957939

978-3-8439-5793-9, Reihe Informatik

Arne Grünhagen
Data Driven Monitoring of the Optical Synchronization System at the European XFEL

242 Seiten, Dissertation Technische Universität Hamburg (2026), Softcover, A5

Zusammenfassung / Abstract

The European XFEL is a cutting-edge research facility enabling state-of-the-art photon science. At the heart of its operation is an optical synchronization system that provides femtosecond-level timing stability, an extraordinary degree of precision essential for the reliable operation of a particle accelerator of this scale.

This dissertation develops methods to monitor, diagnose, and predict performance instabilities and downtime in this complex system. Spanning data acquisition, signal processing, disturbance characterization, and automated diagnosis and prognostics, the work establishes an advanced data processing and analysis pipeline for complex cyber-physical systems.

At its core is a novel framework that combines time-series analysis, frequency-domain methods, domain-specific feature engineering, and deep learning. Integrating automated anomaly detection, clustering, classification, model selection, and hyperparameter optimization, the framework is used to investigate operational disturbances and environmental influences, ranging from earthquakes, ocean-generated microseisms, and human-made noise to system-level anomalies. Its capabilities are demonstrated through controlled optical and acoustic experiments as well as real operational data from the European XFEL.

The results provide a robust and explainable foundation for data-driven condition monitoring and predictive maintenance. By enabling earlier detection, diagnosis, and prediction of disturbances, this work contributes to highly reliable operation and opens new ways for mitigating disturbances in complex scientific infrastructures.