Author: Baurichter, A.
Paper Title Page
THPME001 Permanent Magnets in Accelerators can save Energy, Space, and Cost 3511
  • F. Bødker, L.O. Baandrup, A. Baurichter, N. Hauge, K.F. Laurberg, B.R. Nielsen, G. Nielsen
    Danfysik A/S, Taastrup, Denmark
  • O. Balling
    Aarhus University, Aarhus, Denmark
  • F.B. Bendixen, P. Kjeldsteen, P. Valler
    Sintex A/S, Hobro, Denmark
  • S.P. Møller, H.D. Thomsen
    ISA, Aarhus, Denmark
  • H.-A. Synal
    ETH, Zurich, Switzerland
  Green Magnet technology with close to zero electrical power consumption without the need for cooling water saves costs, space and hence spares natural resources. A compact dipole based on permanent magnets has been developed at Danfysik in collaboration with Sintex and Aarhus University. This first Green Magnet has been delivered to ETH Zurich for testing in a compact accelerator mass spectrometer facility. Permanent NdFeB magnets generate a fixed magnetic field of 0.43 T at a gap of 38.5 mm without using electrical power in the H-type 90° bending magnet with a bending radius of 250 mm. Thermal drift of the permanent magnets is passively compensated. Small air cooled trim coils permit fine tuning of the magnetic field. Magnetic field measurements and thermal stability tests show that the Green Magnet fully meets the magnetic requirements of the previously used electromagnet. The use of Green Magnet technology in other accelerator systems like synchrotron light sources is discussed.  
THPME002 Compact High-Tc 2G Superconducting Solenoid for Superconducting RF Electron Gun 3514
  • G. Nielsen, A. Baurichter, N. Hauge, E.K. Krauthammer
    Danfysik A/S, Taastrup, Denmark
  A solenoid with second generation (2G) high-temperature superconducting (HTS) coils for use in the superconducting RF electron gun of the WiFEL free electron laser at the University of Wisconsin, Madison, has successfully been designed, manufactured, tested and magnetically characterized at Danfysik. The solenoid is designed to operate in the temperature range between 5 K and 70 K. A stack of 16 serially connected pancake coils wound from SuperPower 2G HTS-tape is mounted inside a cylindrical iron yoke with end caps. The solenoid was designed with an excitation current margin of at least 130 % of the nominal operation current in the whole temperature range. At operation, 17.2 kA-turns yield a center field of 0.20 T and a field integral of 3.1 T2 mm, with very small integrated field errors. With a yoke outer diameter of 176 mm and a total length of 136 mm, the solenoid is very compact, and can therefore be placed very close to the RF cavity, improving its emittance compensating efficiency. Careful magnetic design minimizes the leak field at the SC cavity surface. Heat dissipation is negligible hence conduction cooling through copper braids attached to the iron yoke is sufficient.