Radiative regime of linear colliders, high repetetion rate free electron lasers and associated accelerating structures

A review of various scalings of high energy and high luminosity electron–positron colliders in the highly radiative regime is presented together with the electromagnetic and mechanical limitations of various associated acceleration structures to support operation with high gradients and high repetition rates. The potential for operation of normal conducting linacs in a mode of high repetition rate of 1 kHz or higher, relevant for todayʹs linac-driven free electron lasers, is also discussed.