Development of "Flying" RF-Undulators with Regular and Profiled Parameters for FELs of Compton-Type

Conception of Compton FEL-scattrons is under development at IAP RAS and aimed at reducing energy of a driving relativistic electron beam, increasing efficiency of the electron-wave interaction and achieving relative compactness of the generator. The basis of this concept is RF-undulator of a new type - the so-called "flying" undulator, which represent short microwave pulse that synchronously propagates with driving electron bunch and provides pumping of its oscillations. Profiling parameters of "flying" undulator allows realization of the non-resonant trapping regime resulting in further enhancement of the FEL efficiency. Present paper is devoted to the design parameters, results of simulations and "cold" tests of regular and profiled "flying" undulators realized in the Ka and W bands.