Speaker
Description
The European Synchrotron Radiation Facility (ESRF) Extremely Brilliant Source (EBS) was installed in 2019 and commissioned in 2020. The alignment tolerances for the most demanding magnets—including the combined-function magnets, high-gradient quadrupoles, and sextupoles—were approximately 60 µm (2.5σ).
Between 2019 and 2025, no global realignment of the Storage Ring (SR) was made. During this period, however, the overall alignment quality gradually degraded due to the well-characterised ground movements at the ESRF site. Consequently, a full realignment of the SR was undertaken in 2025. The work was completed in two stages: first, during the summer shutdown, four of the 32 SR cells were realigned to validate the procedure; then, during the winter shutdown, all 32 SR cells were realigned, with the aim of bringing the magnets as close as possible to their nominal positions.
This paper/presentation describes the ground movements that motivated the realignment, presents the results achieved, and discusses the practical limits of alignment and realignment on the EBS machine using the equipment, materials, and techniques currently available at the ESRF.
