Performance of high intensity /spl gamma/-rays source driven by the Duke storage ring FEL

In this paper we report the status of the High Intensity /spl gamma/-ray Source facility (HI/spl gamma/S) based on intra-cavity Compton back-scattering inside the OK-4/Duke storage ring FEL (SR FEL). The HI/spl gamma/S is generating beams of /spl gamma/-rays with tuneable energy from 1.8 MeV to 58 MeV and total average flux up to 510/sup 8/ /spl gamma/-rays per second. The /spl gamma/-ray beam is mono-chromatized by on-axis collimator to energy spread as low as 0.2% RMS. The HI/spl gamma/S facility generated in excess of 2,000 hours of the /spl gamma/-ray beam time for nuclear physics user program. We discuss the incoming up-grades of the facility in next five years including the installation of the OK-5 FEL with controllable polarisation and the full-energy booster-injector.