H. Braun, R. Pittin, L. Rinolfi, F. Zhou (CERN, Geneva, CH), B. Mouton (LAL, Orsay, France), R. Miller, D. Yeremian (SLAC, Stanford, USA)
The CLIC Test Facility (CTF3) is an intermediate step to demonstrate the technical feasibility of the key concepts of the new RF power source for CLIC. CTF3 will use electron beams with an energy range adjustable from 180 MeV (3.5 A) to 360 MeV (with low current). The injector is based on a thermionic gun followed by a classical bunching system imbedded in a long solenoidal field. As an alternative, an RF photo-injector is also being studied. We present the beam dynamics studies on how to reach the stringent beam parameters at the exit of the injector. Simulations performed with the E-GUN code showed that a current of 10 A can be obtained in an emittance of the order of 10 mm.mrad at the gun exit. PARMELA results are presented and compared to the requested beam performance at the injector exit. A fast sub-harmonic buncher (SHB) is foreseen, to switch the phase of the bunch trains by 180 degrees from even to odd RF buckets. The specific issues of the SHB fast phase switch (rise time < 4 ns), the short bunch length (< 1.5 mm rms), and small emittances under heavy beam loading conditions are discussed.
Comments or Questions to