Present status of UVSOR-II

After the upgrade in 2003, UVSOR-II, a 750 MeV synchrotron light source, has been operated successfully for about 40 weeks every year. In spring 2005, we have replaced main RF accelerating cavity to improve the Touschek lifetime. With this new cavity, we have started operating the ring with a small emittance of 27 nm-rad. Three undulators are in operation, all of which can be controlled from the SR beam lines by users. On the free electron laser study, it was demonstrated that a high average out-coupled power of several hundred milli-watt level could be achieved with the low emittance electron beam. Coherent terahertz radiation is being intensively studied to provide this intense radiation to users. An ultra fast laser that can be synchronized with the electron beam of UVSOR-II is under commissioning which will be used for various studies, such as laser bunch slicing or coherent harmonic generation. (author)