KAGRA is an only gravitational wave telescope using cryogenic mirror system. Although cryogenic sapphire mirror and suspension is the most direct way to reduce thermal noises, a technical issue is to cope with both cooling and vibration isolation. We worked on this issue for 20 years and realized in KAGRA now. For example, special technologies in KAGRA cooling system are followings;
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KAGRA is a 2G interferometric gravitational wave detector constructed in Japan. Its unique features are using underground site and cryogenic sapphire mirrors. In this talk, I will talk on current status and difficulities of cryogenic mirror suspension and our plan to overcome these issues.
In order to increase strain sensitivity in the 10-200 Hz region of current gravitational wave detectors it is necessary to further reduce the thermal noise of the detector. Proposals have been put forward for the next generation (3G) detectors which will operate at cryogenic temperatures. Silicon is a promising material due to its low mechanical loss, high thermal conductivity and zero thermal...
The observation of gravitational waves is highly influenced by the detectors sensitivity, that is limited for the low frequencies (10 -100 Hz) by the thermal noise. For this reason, the monolithic suspensions are one of the most important upgrades of the interferometric detectors including Advanced Ligo (aLigo) and Advanced Virgo (AdV). Currently the silica fibers are built to minimize the...
The third generation gravitational wave detectors like Einstein Telescope and LIGO Voyager, will adopt cryogenics mirrors and suspension systems as KAGRA interferometer, to reduce thermal noise and improve the sensitivity. The suspension systems or part of them will operate at low or cryogenic temperatures. The problems and challenges of operating the suspension systems and the interferometers...
