• A. Bernhard, T. Baumbach, F. Burkart, S. Ehlers, G. Fuchert, P. Peiffer, M. Wolf, D. Wollmann
  KIT, Karlsruhe
• B. Kostka
  University of Erlangen-Nürnberg, Physikalisches Institut II, Erlangen
• R. Rossmanith
  FZK, Karlsruhe

The ANKA superconductive undulator (SCU14) is continously operated since 2005. The main objetive of this operation was to investigate the interactions between the undulator and the stored electron beam and to characterise the undulator radiation. The characterisation of the undulator radiation was done with a short test beamline designed for spacially and spectrally resolved measurements of the undulator radiation intensity. This contribution summarises the results of these measurements. The spectra are cross-correlated with the magnetic field measurements carried out earlier.

• S. Ehlers, T. Baumbach, G. Fuchert, P. Peiffer, D. Wollmann
  KIT, Karlsruhe
• A. Bernhard, R. Rossmanith
  FZK, Karlsruhe
• D. Schoerling
  IMFD, Freiberg

The next step towards introducing superconductive undulators as the new generation of insertion devices is to understand the impact of dynamic effects in the superconducting coils on the accelerator beam. These effects are seen as a temporal drift of the beam orbit, originating from transients of the magnetic field. The first systematic time resolved measurements of such drifts have been performed ANKA. Orbit displacement during several different ramping cycles, for different ramp rates and relaxation times, has been investigated. This contribution summarises the results of the measurements. The persistent current effects in the superconducting wires, as well as eddy currents in the yoke are discussed as possible sources for the transients.

• P. Peiffer, T. Baumbach, A. Bernhard, G. Fuchert, D. Wollmann
  KIT, Karlsruhe
• R. Maccaferri, Y. Papaphilippou
  CERN, Geneva
• R. Rossmanith
  FZ Karlsruhe, Karlsruhe

NbTi wires are relatively easy to handle and are therefore up to now the preferred material for superconductive insertion devices. Yet other materials, like Nb3Sn, MgB2 or high temperature superconductors, are less sensitive to beam heat load and/or are able to produce higher magnetic fields. In this paper the different superconducting materials and their advantages and challenges are discussed. Additionally this paper describes new designs for special insertion devices like damping wigglers and undulators for laser wakefield accelerators.

• D. Wollmann, T. Baumbach, A. Bernhard, P. Peiffer
  KIT, Karlsruhe
• A.W. Grau, R. Rossmanith
  FZK, Karlsruhe
• E.M. Mashkina
  University Erlangen-Nuernberg, Erlangen

Recently a new concept for automatically reducing magnetic field errors in superconductive undulators was proposed. According to this proposal the field errors are compensated by an array of coupled high temperature superconductor loops attached to the surface of the superconductive undulator. The field errors induce currents in the coupled type II-superconducting loops and, as a result, the magnetic field generated by these currents minimizes the field errors. In this paper the results of a first successful experimental test of this concept are described.