Author: S. Matsui
Institution: Japan Synchrotron Radiation Research Institute (JASRI)
Co-Author: Chao Zhang
Elevation changes of the SPring-8 Storage Ring
After the alignment of the magnets in the storage ring successive elevation measurements revealed floor settlements. The elevation at the 10 m long underpath rises up to a maximum of 0.4 mm during the summer and decreases by 0.4 mm during the winter because of ambient temperature changes. The floor levels over underground drain pipes with a diameter of 0.9m at five locations in the storage ring changes from +/-0.1 to +/-0.2 mm in the same way. The floor over the RF waveguide room settled and is now deforming depending on the temperature in that room. When the commissioning started, without the use of corrector magnets, the horizontal and vertical COD was within +/-5mm. These COD's are on the order of the ones calculated in simulations using the measured alignment error.