• R.P. Walker, R. Bartolini, C. Christou, J.H. Han, J. Kay, I.P.S. Martin, G. Rehm, J. Rowland
  Diamond, Oxfordshire
• D. Angal-Kalinin, M.A. Bowler, J.A. Clarke, D.J. Dunning, B.D. Fell, A.R. Goulden, F. Jackson, S.P. Jamison, J.K. Jones, K.B. Marinov, P.A. McIntosh, J.W. McKenzie, B.L. Militsyn, A.J. Moss, B.D. Muratori, S.M. Pattalwar, M.W. Poole, R.J. Smith, S.L. Smith, N. Thompson, P.H. Williams
  STFC/DL/ASTeC, Daresbury, Warrington, Cheshire
• N. Bliss, G.P. Diakun, M.D. Roper
  STFC/DL, Daresbury, Warrington, Cheshire
• J.L. Collier, C.A. Froud, G.J. Hirst, E. Springate
  STFC/RAL, Chilton, Didcot, Oxon
• J.P. Marangos, J.W.G. Tisch
  Imperial College of Science and Technology, Department of Physics, London
• B.W.J. McNeil
  USTRAT/SUPA, Glasgow
• H.L. Owen
  UMAN, Manchester

The New Light Source (NLS) project was launched in April 2008 by the UK Science and Technology Facilities Council (STFC) to consider the scientific case and develop a conceptual design for a possible next generation light source based on a combination of advanced conventional laser and free-electron laser sources. Following a series of workshops and a period of scientific consultation, the science case was approved in October 2008 and the go-ahead given to continue the project to the design stage. In November the decision was taken that the facility will be based on cw superconducting technology in order to provide the best match to the scientific objectives. In this paper we present the source requirements, both for baseline operation and with possible upgrades, and the current status of the design of the accelerator driver and free-electron laser sources to meet those requirements.

• R. Bartolini, V. Karataev
  JAI, Egham, Surrey
• R. Bartolini, G. Rehm
  Diamond, Oxfordshire

Diamond is a third generation synchrotron light source built to generate infra-red, ultraviolet and X-ray synchrotron radiation (SR) of exceptional brightness. The operation of the Diamond storage ring with short electron bunches for generation of Coherent THz radiation and short X-ray pulses for time-resolved experiments is limited by the onset of microbunch instabilities. We have started a project to investigate the longitudinal electron beam dynamics and microbunch instabilities in the Diamond storage ring. In the first experiment we used an ultra-fast (time response is about 250 ps) Schottky Barrier Diode sensitive to the radiation within the 3.33-5 mm wavelength range. When the single bunch current exceeded 1.9 mA we observed a set of sub-THz bursts appearing quasi-periodically while the beam was circulating in the ring. The fast response allowed us to detect the signal turn-by-turn, which gives us an opportunity to study the bursts’ structure and evolution. It also allows us to study the effect in a multi-bunch mode when bunches are only 2 ns apart. In this report we will present our first preliminary results and also discuss future plans.