ATLAS Superconducting Magnet System Status

Abstract

The ATLAS particle detector presently being installed at the LHC at CERN requires magnetic field for charged particles bending in an 8000 m 3 volume. A system of four superconducting magnets was designed comprising a Central Solenoid making 2 T for the inner detector as well as two End-cap Toroids and a Barrel Toroid generating the about one tesla magnetic field for the muon detectors. The magnet system with a stored energy of 1.6 GJ is sized 22 m in diameter and 26 m in length. After about 15 years of design, construction in industry, system integration at CERN and installation in the underground cavern, the completion is imminent. At present, in August 2006, the Central Solenoid is operational, the Barrel Toroid installation complete and 4 K tests in progress and the 2 End Cap Toroids are being integrated and will soon be installed as well. Magnet services for vacuum, He cryogenics, power converters and circuits as well as controls and safety systems are operational. In the paper the status of the various magnets is reviewed and the first experience and test results with the magnets installed are reported.

Measurement of the ATLAS solenoid magnetic field

“…The ATLAS solenoid was commissioned [4] in the last two weeks of July 2006 and its field was mapped in the first week of August. The ID barrel was installed immediately afterwards, so there was no opportunity to investigate puzzling features in the data by repeating any maps or surveys.…”

The Large Hadron Collider and the Role of Superconductivity in One of the Largest Scientific Enterprises

“…At present the solenoid has been fully tested in its final position [36], while the BT, after successful testing of all 8 coils at 110% of operating current, will be tested in the detector in autumn 2006 [37]. The ECT test is foreseen in summer 2007 [38].…”