• A. Lehrach
  FZJ, Jülich
• K. Aulenbacher, A. Jankowiak
  IKP, Mainz
• W. Hillert
  ELSA, Bonn
• C. Montag
  BNL, Upton, Long Island, New York
• T. Weis
  DELTA, Dortmund

The feasibility of a polarized Electron-Nucleon Collider (ENC) with a center-of-mass energy up to 13.5 GeV for luminosities above 2·10³² cm^-2 s^-1 is presently under consideration. The proposed concept integrates the planned 14 GeV High-Energy Storage Ring (HESR) for protons/deuterons and an additional 3 GeV electron ring. Calculations of cooled beam equilibria including intra-beam scattering and beam-beam interaction have been performed utilizing the BetaCool code. A special design of the interaction region is required to realize back-to-back operation of the HESR storage ring together with the elaborated collider mode. For polarized proton/deuteron beams additional equipment has to be implemented in several machines of the acceleration chain and the HESR to preserve the beam’s polarization. A scheme for polarized electrons is still under investigation. In this presentation the required modifications and extensions of the HESR accelerator facility at the future International Facility for Antiproton and Ion Research (FAIR) are discussed and the proposed concept is presented.

• A. Hofmann, M. Fitterer, M. Klein, A.-S. Müller, K.G. Sonnad
  KIT, Karlsruhe
• G. Blokesch
  PPT, Dortmund
• E. Huttel, N.J. Smale
  FZK, Eggenstein
• S. Marsching, T. Weis
  DELTA, Dortmund
• C. Piel
  ACCEL, Bergisch Gladbach
• R. Weigel
  Max-Planck Institute for Metal Research, Stuttgart

Funding: This work has been supported by the Initiative and Networking Fund of the Helmholtz Association under contract number VH-NG-320.

The microtron of the ANKA injector is presently equipped with a diode- type electron gun, which produces long pulses. A new thermionic DC triode-type electron gun has been ordered and foreseen for installation in the ANKA injector. The new gun allows single bunch as well as long pulse operation, thus offering the possibility to study beam properties in single bunch operation. This is particularly of interest for the investigation of the short bunch dynamics in the generation of coherent THz radiation. Furthermore, the new gun will make time resolved measurement possible. Simulations of the gun-to-microtron transport with special emphasis on the emittance evolution e.g. due to space charge have been done. Measurements of the gun performance are presently underway and are summarised in this paper.