PAL XFEL Linac RF System
The PAL XFEL hard X ray linac has a 716 m long gallery and tunnel for 10 GeV. Forty nine modulators are necessary in the hard X ray gallery for an X band linearizer, an S band RF gun, two S band deflectors and 45 S band klystrons for accelerating structures. They have been installed completely from March 15, 2015 to December 30, 2015 after completing the building construction. There are 51 modulators, 178 accelerators structures, 42 SLEDs in the hard X ray linac and the soft X ray linac. The RF conditioning of the klystrons, SLEDs and accelerating structures were stated from November 24, 2015. We describe the PAL XFEL system and the current status of the linac RF system.