Cryogenic systems of the Cryogenic Laser Interferometer Observatory

Cryogenic Laser Interferometer Observatory (CLIO) is a laser interferometric gravitational wave detector using cryogenic cooled mirrors. In order to cool the mirrors, cryogenic environment is necessary. We made four vacuum chambers with cryogenic cooled shields inside. The mirror is suspended by a mirror suspension system with a heat path for transferring heat from the mirror to the shield. Test cooling of the chambers and the mirror suspension system has been done. After one week cooling, the chambers was cooled from 8K to 10K and the mirror were cooled at 21K successfully.