title: Vacuum-compatible vibration isolation stack for an interferometric gravitational wave detector TAMA300
abstract: Interferometric gravitational wave detectors require a large degree of vibration isolation. For this purpose, a multilayer stack constructed of rubber and metal blocks is suitable, because it provides isolation in all degrees of freedom at once. In TAMA300, a 300 m interferometer in Japan, long-term dimensional stability and compatibility with an ultrahigh vacuum environment of about 10/sup -6/ Pa are also required. To keep the interferometer at its operating point despite ground strain and thermal drift of the isolation system, a thermal actuator was introduced. To prevent the high outgassing rate of the rubber from spoiling the vacuum, the rubber blocks were enclosed by gas-tight bellows. Using these techniques, we have successfully developed a three-layer stack which has a vibration isolation ratio of more than 10/sup 3/ at 300 Hz with control of drift and enough vacuum compatibility
keyphrases: vibration isolation stack interferometric gravitational wave detectors multilayer stack metal blocks 300 m long-term dimensional stability ultrahigh vacuum environment 10/sup -6/ Pa operating point ground strain thermal drift thermal actuator rubber blocks gas-tight bellows 300 Hz vacuum compatibility TAMA300 interferometer rubber outgassing