PERFORMANCE OF AN ACTIVE VIBRATION ISOLATION SYSTEM

In the future linear collider project, the tunnel floor stability is required to be several tens of nanometers in the main linac section, and sub-nanometer in the interaction region in the vertical direction [1]. These severe tolerances are required in order to transport and collide very small beams. The beam size is several nanometers vertically, and several hundred nanometers horizontally at the interaction point. In order to achieve this stability, some vibration isolation system will be needed. Active vibration system utilizing piezoelectric actuators were tested and their performance was reported [2-4]. An active vibration isolation system, utilizing pneumatic valves, was fabricated and tested. Test results on performance of this active vibration isolation system are reported.