ATLAS End Cap Toroid Cold Mass and Cryostat Integration

The ATLAS experiment at LHC (CERN) will utilize a large, superconducting, air-cored toroid magnet system with a long Barrel Toroid and two End Cap Toroids. Each End Cap Toroid will contain eight racetrack coils mounted as a single cold mass in a cryostat vessel of approximately 10 m diameter. This paper presents the design principles and realization of the cold mass assembly. The procedures for integration of the full cold mass, 120 tonnes, into the vacuum cryostat are described. The overall status of toroid magnet integration and planning for test and installation is reviewed