PLS-II LINAC UPGRADE

We report on the recent status of the Pohang Light Source (PLS-II) linac at Pohang Accelerator Laboratory (PAL). From 2009, the linac upgrade has been started increasing its energy from 2.5 GeV to 3 GeV aiming stable top-up operation. Top-up operation requires high energy stability from the linac beam energy and machine reliability of the linac modulator systems. Especially, thus we present machine stability including RF and modulators as well as beam energy stability using diagnostic system. Finally, we will discuss the beam stability optimization.