The goal of phase 3 is a complete working CW MM-Wave FEL.
Illustration of the final FEL configuration
The components indicated in red will be added to complete Phase 3. The FEL is configured with a helical permanent-magnet undulator and a round TE11 waveguide resonator terminated by Bragg reflectors. These choices were motivated primarilly by the need to minimize any beam current loss and the constraints listed below.
Challenging issues associated with phase 3 include: