New directions in RF sources

We examine the various high power RF sources on the basis of the next linear collider requirements. The discussion is based on classification of the sources according to what we consider the most informative criteria. In the conventional acceleration scheme (e.g. SLAC) multiple sources generate the RF power. A variety of sources are considered and they cover the spectrum from 9 to 19 GHz. In the two beam accelerator scheme all the modules are driven by the same beam which has multi MeV (LBL/LLNL) up to a few GeV (CERN) electrons; the current carried by the beam is of order of kA. Two types of RF sources have been suggested: traveling wave (TW) structures and free electron laser (FEL). The operating frequency varies from device to device in the range of 9 to 35 GHz.<>