|AVS 57th International Symposium & Exhibition|
|Vacuum Technology||Wednesday Sessions|
|Session:||Accelerators, Large Vacuum Systems, and Vacuum Surfaces|
|Presenter:||R. Takahashi, National Astronomical Observatory of Japan|
|Authors:||R. Takahashi, National Astronomical Observatory of Japan
Y. Saito, KEK-High Energy Accelerator Research Organization, Japan
T. Suzuki, KEK-High Energy Accelerator Research Organization, Japan
|Correspondent:||Click to Email|
The large-scale cryogenic gravitational wave telescope (LCGT) project is proposed to open a new window for astronomy, which will be able to detect signals from the binary neutron star coalescence at 240Mpc away. LCGT requires an ultra-high vacuum tubes which the laser beams pass through. Two 3-km vacuum tubes are kept in ~10-7Pa of vacuum pressure so as to reduce scattering-effects due to residual gas molecules.
Mirrors of the main interferometer are cooled to 20K to reduce thermal noises. The super-insulator (SI) which consists of multi-layered organic films is generally used for a thermal insulation of cryostat. However, the SI should not be applied to the cryostat of LCGT to avoid contamination on the extremely sensitive mirrors. We plan to use multi-layered metal shields with low emissivity and low outgassing for a thermal insulation.