• J.A. Clarke, D.J. Dunning, S. Leonard, A.D. Smith, N. Thompson
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• M. Surman
  STFC/DL/SRD, Daresbury, Warrington, Cheshire

An infra-red oscillator FEL was installed into the accelerator test facility, ALICE, at Daresbury Laboratory at the end of 2009. The FEL will be used to study energy recovery performance with a disrupted, large energy spread, beam and also to test novel FEL concepts. This paper will describe the installed hardware, the pre-alignment techniques that have been employed, the diagnostics that are being used to detect the infra-red output, and the progress with commissioning of the FEL itself.

• J. Henderson, B.W.J. McNeil
  USTRAT/SUPA, Glasgow
• D.J. Dunning
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire

The method of Echo Enabled Harmonic Generation is a possible method of achieving coherent short wavelengths in an FEL amplifier. In this paper the effects of noise variations is some of the important parameters affecting the stability of the final harmonic bunching of the electron beam are investigated numerically.

• D.J. Dunning, N. Thompson
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• B.W.J. McNeil
  USTRAT/SUPA, Glasgow

The effects of pre-conditioned electron beams on free electron laser (FEL) behaviour are considered in simulations. Under consideration is modulation of the electron beam energy, using long-scale modulation period relative to the resonant FEL wavelength. Structure can be generated in the radiation field and electron beam with extent of significantly less than the FEL co-operation length, without applying spatio-temporal shifts between the radiation and electron beam*.

* N.R. Thompson and B.W.J. McNeil, Phys. Rev. Lett. 100, 203901 (2008).