Author: Jeon, M.Y.
Paper Title Page
WEP058
Development of a Hybrid Electromagnetic Planar Undulator Having Horizontal Focusing Force for a Compact THz FEL  
 
  • S. Bae, B.A. Gudkov, K.H. Jang, Y.U. Jeong, K. Lee, S.V. Miginsky, J. Mun, S. Park
    KAERI, Daejon, Republic of Korea
  • M.Y. Jeon
    Chungnam National University, Daejoen, Republic of Korea
 
  A THz table-top FEL is under development at KAERI for security applications. We developed a compact microtron to accelerate electrons up to 5 MeV with an energy spread of about 0.4%. A hybrid electromagnetic planar undulator was designed and fabricated to cover the FEL's lasing wavelength range of 400~600 μm. The magnetic field strength in the gap of the undulator is changeable from 0.76 to 1.14 T by varying the coil current of the undulator from 1.5 to 2.5 kA. The undulator provides a horizontal focusing force to keep the low energy electrons passing a specially-designed narrow waveguide. The undulator field error of 1st and 2nd integrals, which is 3.61 x 10-4 T·m and 5.75 x 10-5 T·m2, respectively, was minimized to reduce the deflection angle and trajectory offset of electron beam to pass through the waveguide having a width of 10 mm.