Vibration measurements and analysis of the final focusing superconducting magnet system (QCS)

The SuperKEKB project which is aiming for 40 times higher luminosity than that of KEKB accelerator is in progress at High Energy Accelerator Research Organization (KEK). One of the method to realize this purpose, two final focusing superconducting quadrupole magnets (QCS) which can be squeeze the vertical beam size to 50 nm are required in the interaction region. Installation of those QCS magnets have been already finished and one of it (QCSL) has been finished the performance test. The other one (QCSR) is in progress of field mapping. Because the vibration of the QCS is important issue for achievement of the target luminosity, the vibration measurements were carried out after the installation. Also the vibration level was estimated by FEM calculation based on the measurement floor data. In this paper, it describes about the results of the vibration measurements of the QCS magnets and the comparison between the measurements and FEM analysis is reported. (author)