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arXiv · 0911.3090

Thermal-noise-limited underground interferometer CLIO

Kazuhiro Agatsuma·Koji Arai·Masa-Katsu Fujimoto·Seiji Kawamura·Kazuaki Kuroda·Osamu Miyakawa·Shinji Miyoki·Masatake Ohashi·Toshikazu Suzuki·Ryutaro Takahashi·Daisuke Tatsumi·Souichi Telada·Takashi Uchiyama·Kazuhiro Yamamoto·CLIO collaborators
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Abstract

We report on the current status of CLIO (Cryogenic Laser Interferometer Observatory), which is a prototype interferometer for LCGT (Large Scale Cryogenic Gravitational-Wave Telescope). LCGT is a Japanese next-generation interferometric gravitational wave detector featuring the use of cryogenic mirrors and a quiet underground site. The main purpose of CLIO is to demonstrate a reduction of the mirror thermal noise by cooling the sapphire mirrors. CLIO is located in an underground site of the Kamioka mine, 1000 m deep from the mountain top, to verify its advantages. After a few years of commissioning work, we have achieved a thermal-noise-limited sensitivity at room temperature. One of the main results of noise hunting was the elimination of thermal noise caused by a conductive coil-holder coupled with a pendulum through magnets.

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Kazuhiro Agatsuma, Koji Arai, Masa-Katsu Fujimoto, Seiji Kawamura, Kazuaki Kuroda, Osamu Miyakawa, Shinji Miyoki, Masatake Ohashi, Toshikazu Suzuki, Ryutaro Takahashi, Daisuke Tatsumi, Souichi Telada, Takashi Uchiyama, Kazuhiro Yamamoto, CLIO collaborators. 2010-01-29. Thermal-noise-limited underground interferometer CLIO. https://doi.org/10.1088/0264-9381%2F27%2F8%2F084022

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