Optic issues in ongoing ERL projects

A wide range of optics issues for energy recovery linac (ERL)-based projects are illustrated through the presentation of ongoing projects covering both light sources, at Cornell and Daresbury and high energy and nuclear physics accelerators at the Brookhaven National Laboratory. This presented range of projects demonstrates how the different designs teams see the challenges of studying and solving optics issues for their particular project's ERLs, with studies appropriate to the stage of maturity of the project. Finally, as an illustration of the complexity and detail behind a single aspect of ERL optics design we present an overview of the highly important generic topic of longitudinal phase space evolution in ERLs.