The CUORE cryostat: a 10 mK infrastructure for large bolometric arrays

The Cryogenic Underground Observatory for Rare Events (CUORE) experiment is presently in the final phases of its commissioning at the Gran Sasso Underground Laboratory (Italy). The CUORE cryogenic system will have to guarantee the optimal operation temperature of the detector (similar to 10 mK) for a live-time of 5 years. Furthermore, to avoid radioactive background, about 7 tonnes of lead are cooled to below 4K and only few construction materials are acceptable. The CUORE detector will be by far the largest mass ever cooled to 10 mK. A description of the CUORE cryostat is presented and the specific characteristics and the performances are illustrated. The results of the (recently concluded) cryostat commissioning are also reported. They show that the CUORE cryostat is now ready to host the detector, thus confirming the possibility of realizing large bolometric arrays for rare event physics.