The superconducting magnet system for the ATLAS Detector at CERN

The superconducting magnet system for the ATLAS Detector for the Large Hadron Collider at CERN is under construction since 1997. The magnet system is a hybrid of 4 superconducting magnets, a 2.5 m bore, 5.3 m long 2 T central solenoid servicing the inner detector and three 4 T toroids with global dimensions of 20 m diameter, 25 m long providing the magnetic field of about 1 T for the muon detectors. The operating currents of the solenoid and toroids are 8 and 20 kA respectively with a total stored energy of 1.6 GJ. The realization of the system is challenging due to its unusual size and complexity. Last year the construction of the coils and cryostats commenced in industry. The manufacture of the solenoid cold mass is already finished and the delivery of the individual toroid coils will commence in 2001. An on-surface test of all magnets will occur. After installation in a new cavern 100 m underground this will start in 2003 leading to commissioning of the entire magnet system in early 2005. In the paper various magnets are introduced as well as the common infrastructure and services required. The status of the project is reviewed. (15 refs).