Simulations of the LANL 1 KW regenerative amplifier FEL

Abstract

The development of a high average power FEL for military applications would represent a significant improvement in missile defense, especially shipboard self defense. The LANL regenerative amplifier FEL (RAFEL) is designed to produce an average output power of 1 kW. This FEL represents a significant increase in average power demonstrated in an FEL and also provides a test of the concept of combining the FEL oscillator and amplifier designs. Simulations were performed to better understand the physics behind the LANL RAFEL operation. Simulations study the transverse effects due to optical guiding by the intense electron beam and feedback. These simulations are applied to optimizing the undulator taper rate, feedback optimization, and initial phase velocity. Additional simulations study the longitudinal effects due to short electron pulses and optical pulse development over multiple passes. Finally, simulations of the RAFEL design using an ideal beam expand on understanding of the design's basic characteristics and limitations