WEICLH1057
JAI, Oxford, United Kingdom
Cockcroft Institute, Lancaster University, Lancaster, United Kingdom
The next generation light sources are to be compact, highly efficient, have high repetition rates and high-brilliance radiation pulses. To generate such a beam a high charge electron beam is required. Adding an energy recovery (ER) stage to improve efficiency leads to the appearance of beam break-up instabilities as the use of same or strongly coupled cavities in ER means that the positive feedback between electron's transverse momentum and the high order modes is readily established. The ultimate goal of the UH-FLUX project is to design a compact, efficient, a single turn [1] SRF ERL, capable of driving either source of THz or X-ray radiation. In the deceleration section most of the beam energy is extracted and guided through a resonant coupler back to acceleration section. The sections consist of the same number of cells, adjusted to insure that only the operating modes of both structures are fully overlapping [2]. It is expected that the ERL will be capable of generating fs, up to 1nC bunches of energies from 10MeV to 100MeV. We show (via analytical and numerical models) that in this case the regenerative BBU instability can be minimised allowing high currents to be achieved.
[1] International Patent Application No. PCT/GB2012/052632 (WO2013/061051) filed 26 October 2012
[2] UK Priority patent application 1420936.5 filed November 2014
