Operational status of PLS 2-GeV electron linac

The PLS 2-GeV electron linac at the Pohang Accelerator Laboratory (PAL) has been served as a full energy injector to the storage ring called the Pohang Light Source (PLS) since September 1994. The linac uses eleven 80-MW klystrons driven by 200-MW modulators. There are 42 constant gradient accelerating sections and 6 quadrupole triplets. During the period from September 1994 to December 1995, the accumulated beam operation exceeded 4,000 hours. However, the average operation time of individual klystron reached to 17,200 hours as of December 1995. This time was counted after the installation of individual klystron starting from November 1992. We have lost one klystron which was the oldest one placed at the module no. 2 during the summer maintenance period in 1995. The expected beam operation in 1996 is about 5,000 hours. We report the current status of the linac and several upgrades - mostly computer control system and beam diagnostics - based on our operational experiences achieved during the commissioning and normal operations. (author)