Construction Status of Main Magnet for CYCIAE-100

A new radioactive ion beam project, Beijing Radioactive Ion-beam Facility (BRIF), has been started at CIAE since 2004 . In this project, a 100 MeV H- cyclotron, CYCIAE-100, is selected as the driving accelerator providing 75-100 MeV, 200-500 proton beam. CYCIAE-100 is consisting of the main magnet, RF system, ion source and injection system, dual beam extraction system, etc. The progress of this machine had been reported elsewhere . The main magnet is the most critical part and had been numerically simulated and delicately designed . The techniques for main magnet construction are investigated in detail . The construction of this compact style, 450 ton cyclotron magnet has been started since 2007. The imperfection control of the large scale casting steel, the deformation and fabrication tolerance, etc., have all posed a challenge to the capacity limitation of cyclotron lab at CIAE for magnet design, mapping and shimming, and of industry for steel production/machining in the world. The design highlight of the magnet will be briefly introduced and the emphasis in this paper will be given to the construction progress.