The JLab Ampere-Class cryomodule

We report on the design of a new cryomodule capable of accelerating high-current beams for future ERL based high power compact FELs. We discuss the factors influencing the design choices, including BBU threshold, frequency, HOM power, real-estate gradient, peak surface fields, and operating efficiency. We present a conceptual design that meets the requirements of compact MW-class FEL, however this module design could be useful for a wide range of applications such as electron cooling, electron-ion colliders, industrial processing etc. The concepts developed for this design could also be useful for larger ERL-based light sources, XFELs and even linear colliders