Storage ring free-electron lasers: Dynamics and characteristics.

摘要

Storage rings provide high brightness electron beams required for operation of short wavelength free electron lasers (FELs). Storage ring FELs have held the short wavelength record for the last ten years. A number of laboratories around the world, including the Duke FEL Laboratory, are pursuing the goal of developing tunable X-ray lasers.; The Duke electron storage ring, which was successfully commissioned in November of 1994, is dedicated to drive XUV FELs. The first XUV FEL, the OK-4 optical klystron, completed its trans-Atlantic trip from Novosibirsk, Russia, and has been installed on the Duke storage ring. It has been commissioned with electron beam in November of 1995. We are presenting preliminary results on its performance.; This thesis is dedicated to the physics of storage ring FELs. A complete six dimensional description of the electron beam and FEL interaction was developed to describe the dynamics of storage ring FELs. A novel self-consistent model was developed for computer simulations to verify theoretical predictions of FEL performance on the Duke storage ring. During this study we discovered a new phenomenon: superpulses with unexpectedly high power. We found a theoretical explanation of these superpulses, and called the mechanism phase-space refreshment.; Successful operation of the Duke storage ring and OK-4 system gives us the confidence that their performance described in this thesis will be reached in the near future. We plan to surpass both the short wavelength record held by the OK-4 FEL, and the average power record held by the MK III FEL, during the next year when the OK-4 optical cavity will be installed.; We also discuss future plans for novel FELs and novel techniques. In particular, we discuss installation of a special wiggler to generate soft X-ray coherent harmonics, and special modes of storage ring operation (near-isochronous mode and/or resonant mode) to exceed existing theoretical power limitations.; Duke storage ring FELs have many exciting applications including the production of intense quasi-monochromatic gamma ray beams from the OK-4 FEL.