CLIO is the Cryogenic Laser Interferometer Observatory, a prototype detector for gravitational waves. It is testing cryogenic mirror technologies for the future Large Cryogenic Gravity Telescope (LCGT)

LCGT

The Large Scale Cryogenic Gravitational Wave Telescope is a future project of the gravitational wave studies group at the Institute for Cosmic Ray Research of the University of Tokyo. The ICRR was established in 1976 for cosmic ray studies, and is currently working on TAMA 300...

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It is an optical interferometer with two perpendicular arms 100 m long. Uniquely, the mirrors are cooled to 20 K. This reduces various thermal noise sources which trouble other gravity observatories, but cooling the mirrors (which is heated by the powerful laser used in the interferometer) while keeping them isolated from vibrations is difficult.

CLIO is situated 1000 m underground in the Kamioka mine, Gifu Prefecture

Gifu Prefecture

is a prefecture located in the Chūbu region of central Japan. Its capital is the city of Gifu.Located in the center of Japan, it has long played an important part as the crossroads of Japan, connecting the east to the west through such routes as the Nakasendō...

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Japan

Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...

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CLIO is one of the science facilities for physics of the Institute for Cosmic Ray Research of the University of Tokyo

University of Tokyo

, abbreviated as , is a major research university located in Tokyo, Japan. The University has 10 faculties with a total of around 30,000 students, 2,100 of whom are foreign. Its five campuses are in Hongō, Komaba, Kashiwa, Shirokane and Nakano. It is considered to be the most prestigious university...

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