The Mechanical Stability of the Electron Beam Position Monitor at the Taiwan Light Source

The mechanical stability of electron beam position monitor (BPM) is essential for accurately monitoring and controlling electron orbit stability. Many factors, such as storage ring floor movement, thermal expansion of support structure and the movement of BPM vacuum chamber will affect its accuracy. In this paper we report the measured results of storage ring floor motion, the motion of the BPM support structure and BPM vacuum chamber. We found the major factors contributing to BPM motion were the electron beam current power, air temperature and storage ring floor displacement