Author: Li, M.
Paper Title Page
MOPFI028 Physical Design Progress of an 800 MeV High Power Proton Driver 342
  • J.J. Yang, Shizhong. An, M. Li, T.J. Zhang, J.Q. Zhong
    CIAE, Beijing, People's Republic of China
  We presented the conceptual design of an 800 MeV high power proton ring cyclotron in the paper[1] . A more detailed physical design was carried out since then. The most challenging issues regarding the high power operation, including the space charge effects and beam loss during the extraction, are quantitatively studied by using state-of-the-art high performance computation technique. On that basis the fundamental structure of the cyclotron is adjusted and optimized so as to meet the requirements of MW-class operation. Reference: [1] T. Zhang, J. Yang, M. Li, et. al., Conceptual design of an 800 MeV high power proton driver, Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms 269(24) (2011) 2964-2967  
TUPWA011 Investigation of Emittance Growth in a Small PET Cyclotron CYCIAE-14 1745
  • M. Li, Shizhong. An, T.J. Zhang
    CIAE, Beijing, People's Republic of China
  In order to satisfy the rapidly increased domestic needs for PET in China, a small medical cyclotron named CYCIAE-14 is designed and constructed in CIAE ( China Institute of Atomic Energy ) . As the beam intensity in CYCIAE-14 is high, the beam emittance should be controlled strictly in order to reduce the beam loss in the cyclotron. Precessional mixing and resonance crossing are the two main factors leading to emittance growth in the cyclotron with stripping extraction. In this paper, the physical mechanism of precessional mixing in a stripping extraction cyclotron is investigated. After that, the maximum allowable field errors in CYCIAE-14 are derived using the Hamiltonian formalism and numerical simulation, which provides a reference for the cyclotron design and field shimming.  
TUPWA012 The Influence of the Magnetic Field Errors in CYCIAE-100 Cyclotron 1748
  • H.J. Yao, M. Li, T.J. Zhang, J.Q. Zhong
    CIAE, Beijing, People's Republic of China
  The main magnet size of CYCIAE-100 is 2.31 m in height and 6.16 m in diameter and the outer radius of the sector is 2.0 m, and the total iron weight is about 415t. The magnetic filed can not be absolutely ideal because of imperfections during manufacturing and installation of this big magnet. Therefore the influence of the magnetic field errors on the beam behavior should be studied to provide the reference for magnet mapping and shimming. Magnetic field errors in a cyclotron will excite coherent oscillations through displacing the center of orbit or distorting the transverse phase space. This effect is especially important in the CYCIAE-100 cyclotron because there are a number of different turns in the extracted beam. The tolerances for the magnetic field errors are given in this paper based on analytic calculations and numerical simulations. The resonances vr=1, 2vr=2 driven by the 1st, 2nd harmonic magnetic field are considered, which will result in the radial emittance growth .Besides that, the resonances cause the vertical emittance growth are considered. The maximum allowable field errors for CYCIAE-100 are presented in this paper.  
THPME008 Experimental Study of Magnetic Properties for Magnet Material in CYCIAE-100 3525
  • J.Q. Zhong, T. Cui, M. Li, C. Wang, Z.H. Wang, J.J. Yang, T.J. Zhang
    CIAE, Beijing, People's Republic of China
  The magnetic property of magnet material is one of the key factors that influence the distribution of magnetic field in large scale cyclotrons, especially embody on the vertical focusing of field and the first harmonic field error in cyclotron. According to the requirements of the physical design of CYCIAE-100, we have studied the pivotal factors, which impact on the maximum permeability, coercivity and B-H curve of material of CYCIAE-100 magnet, including the cooling rate during magnetic annealing and residual stress. The study results will be shown in this paper.