Update on quadruple suspension design for advanced LIGO

S. M. Aston, C. A. Cantley, LIGO Scientific Collaboration

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94 Citations (Scopus)


We describe the design of the suspension systems for the major optics for Advanced LIGO, the upgrade to LIGO-the Laser Interferometric Gravitational-Wave Observatory. The design is based on that used in GEO600-the German/UK interferometric gravitational wave detector, with further development to meet the more stringent noise requirements for Advanced LIGO. The test mass suspensions consist of a four-stage or quadruple pendulum for enhanced seismic isolation. To minimize suspension thermal noise, the final stage consists of a silica mirror, 40 kg in mass, suspended from another silica mass by four silica fibres welded to silica ears attached to the sides of the masses using hydroxide-catalysis bonding. The design is chosen to achieve a displacement noise level for each of the seismic and thermal noise contributions of 10(-19) m/root Hz at 10 Hz, for each test mass. We discuss features of the design which has been developed as a result of experience with prototypes and associated investigations.
Original languageEnglish
Article number235004
Number of pages26
JournalClassical and Quantum Gravity
Issue number23
Early online date22 Oct 2012
Publication statusPublished - 7 Dec 2012


  • gravitational waves
  • seismology
  • LIGO scientific collaboration

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