Getmanov, Ya.V.; Shevchenko, O.A.; Atkinson, T.; Vinokurov, N.A.: Longitudinal stability of multi-turn ERL with split accelerating structure. In: Proceedings of 4th International Particle Accelerator Conference, IPAC 2013, May 13-17, 2013, Shanghai, China, 2013. - ISBN 978-3-95450-122-9, p. WEPWA047/2226-2228
http://accelconf.web.cern.ch/AccelConf/IPAC2013/papers/wepwa047.pdf
Open Access Version
Abstract:
Some modern projects of the new generation light sources use the conception of multipass energy recovery linac with split (CEBAF-like) accelerating structures [1 - 4]. One of the advantages of these light sources is the possibility to obtain a small bunch length. To help reduce it, the longitudinal dispersion should be non-zero in some arcs of the accelerator. However small deviations in voltages of the accelerating structures can be enhanced by induced fields from circulating bunches due to the dependence of the flight time on the energy deviation and the high quality factor of the superconducting radiofrequency cavities. Therefore, instabilities caused by interaction of electron bunches and fundamental modes of the cavities can take place. The corresponding stability conditions are discussed in this paper. Numerical simulations were performed for two projects – MARS [4] and FSF [3].