0.3-nm SASE-FEL at PAL

Recent success in SASE-FEL experiments provides high confidence in achieving FEL radiation wavelengths as short as 0.1 nm.The SASE-XFEL requires multi-GeV electron beams with extremely low-emittance, short bunches, and long undulator systems. PAL is operating a 2.5-GeV electron linac as a full-energy injector to the PLS storage ring. With a proposed energy upgrade to 3.0 GeV and an in-vacuum undulator, PAL will be able to produce coherent X-ray radiation at wavelengths as short as 0.3 nm.This paper presents the preliminary design details for the proposed PAL-XFEL. The required undulator period is 12.5 mm with a 3-mm gap. The third harmonic enhancement technique can be used to obtain radiation wavelengths of 0.1 nm.The technical parameters related to these goals are reviewed.