• T.J. Zhang, Y.L. Lu, C. Wang, S.M. Wei, J.J. Yang, H.J. Yao, J.Q. Zhong
  CIAE, Beijing

CYCIAE-100 is a 100 MeV, 200 muA H^- cyclotron being constructed at CIAE. The tolerance of the magnetic field is as tight as 1.2 Gauss for isochronous field and 2 Gauss for first harmonics. Due to the absence of coil adjusting in this machine, a measure that helps to achieve a more compact structure (435 ton for the main magnet), the imperfection hence becomes a much more critical factor in our consideration. The effects by the various kinds of imperfection are investigated numerically and the imperfection fields are predicted for beam dynamics simulation, serving as a basic guidance in the magnet construction for CYCIAE-100. Some of the important results will be reported in this paper, including

1. the deformation of the main magnet by the gravity itself, 480 ton EM force and 120 ton vacuum pressure,
2. segregation, inclusion and contraction cavity induced by the casting procedure,
3. fabrication and assembling tolerance, and
4. thermal deformation.