Author: Zhang, M.
Paper Title Page
THPS021 Methods to Obtain High Intensity Proton Ion Beams with Low Emittance from ECR Ion Source at Peking University 3463
 
  • H.T. Ren
    Graduate University, Chinese Academy of Sciences, Beijing, People's Republic of China
  • J.E. Chen, Z.Y. Guo, P.N. Lu, S.X. Peng, Z.Z. Song, J.X. Yu, M. Zhang, J. Zhao, Q.F. Zhou
    PKU/IHIP, Beijing, People's Republic of China
 
  Funding: Supported by the National Science Foundation of China 11075008.
With the development of accelerator technology, to obtain an ion beam with high intensity and low emittance is becoming one of the main goals of research for ion sources. At Peking University we have developed several 2.45 GHz electron cyclotron resonance (ECR) ion sources for different projects and we paid close attention to the beam intensity increasing as well as the beam emittance reduction. Methods are adopted to improve beam intensity by increasing the density of plasma inside the discharge chamber, optimizing the geometry pinch effect and the perveance at the extraction aperture. To suppress the emmitance increasing of an extracted beam, the shape of the electrodes as well as the voltage of suppression electrode are carefully selected With these efforts, a 120 mA total proton beam has been extracted from the permanent magnet ECR ion source at 50 kV, and the measured normalized rms emittance is less than 0.2 pi.mm.mrad. The beam current density at the extraction aperture is about 420 mA/cm2.