Major Upgrade Activity of the PLS in PAL: PLS-II

The Pohang Accelerator Laboratory (PAL) celebrated its 20th anniversary this year. After the completion of the Pohang Light Source (PLS) construction in 1994, the PLS started user service with two beamlines in 1995. The PLS energy was 2.0 GeV. The first major upgrade of the PLS had been done from 2000 to 2002, in which operation energy of the PLS was increased from 2.0 GeV to 2.5 GeV. The number of beamlines has been steadily increased since the start of user service. The number of beamlines currently in service is 28. Three beamlines are under construction. Number of users and performed experiments in 2007 were respectively 2553 and 837. Average impact factor of published papers is over 3.0, which is one of the best among Korean research institutes. Based on such success, the PAL is pursuing the second upgrade plan, called the PLS-II. The PLS will be upgraded its energy from 2.5 GeV to 3.0 GeV. With the upgrade, it will be possible to construct ten more insertion devices. The brightness of the PLS-II will be more than a order higher compared to the current PLS. In this presentation, details of the PLS-II project will be introduced.