Duke storage ring UV/VUV FEL: Status and prospects

A 1.1 GeV electron storage ring dedicated for UV-VUV FEL operation was commissioned last year at the Duke University Free Electron Laser Laboratory [VN. Litvinenko et al., Commissioning of the Duke storage ring, Proc. 1995 Particle Accelerator Conf., Dallas, TX, May 1-5, 1995]. The XUV FEL project, based on the collaboration of the Duke FEL Laboratory and Budker Institute for Nuclear Physics (Novosibirsk, Russia) is described. The OK-4 UV FEL has arrived from Novosibirsk at the Duke FEL laboratory and is in the process of installation. The main parameters of the Duke Free Electron Laser Laboratory (DFELL) storage ring, the OK-4 optical klystron, and the experimental set-up are presented. The parameters of the UV-VUV FEL are given and possible future upgrades to this system are discussed. We have developed a new macro-particle code for storage ring simulation including all known mechanisms of storage ring FEL interaction. We confirm our expectations on the average and peak power for the OK-4. In addition we have studied a giant pulse mode of operation. A new mechanism of "super-pulse" generation was discovered during these studies. It allows the generation of peak power up to 10 GW using "phase-space" refreshment of the electron beam caused by synchrotron motion [V.N. Litvinenko, B. Burnham, J.M.J. Madey and Y. Wu, Nucl. Instr. and Meth. A 358 (1995) 334].