• Y.G. Son, K.R. Kim, S.H. Nam, S.J. Park
  PAL, Pohang, Kyungbuk
• T. Asaka
  JASRI/SPring-8, Hyogo-ken

Funding: This work was supported by the MEST (Ministry of Education, Science and Technology) and the POSCO (POhang iron and Steel making COmpany) in Korea.

The PLS-II, the major upgrade program of the PLS (Pohang Light Source, a 2.5-GeV 3rd generation light source), is planned at the Pohang Accelerator Laboratory. The PLS 2.5-GeV linear accelerator, being the full-energy injector for the PLS storage ring, should be upgraded to provide the beam energy of 3 GeV. For the PLS-II linac, we are going to establish a dual electron gun system in which two guns will be on the accelerator beamline with a bending magnet enabling immediate switching of guns. The dual gun system is expected to achieve high reliability for the top-up injection to the PLS-II storage ring. Also the gun will be upgraded to provide the beam energy of 200 keV and a pulse high-voltage modulator will be constructed. Fifteen-section PFNs will be connected in series to make final impedance of approximately 17.3 ohm. A new modulator applying the inverter technology will be used to charge the PFN and obtain more stable charging performances. In this article the authours would like to report on the design status of the accelerator beamline and inverter modulator for the dual gun system.

• S.H. Kim, M.-H. Cho, W. Namkung, H.R. Yang
  POSTECH, Pohang, Kyungbuk
• S.D. Jang, S.J. Park, Y.G. Son
  PAL, Pohang, Kyungbuk
• J.-S. Oh
  NFRI, Daejon

Funding: This work is supported by KAPRA and POSTECH Physics BK21 Program.

An intense L-band electron linac is now being commissioned at ACEP (Advanced Center for Electron-beam Processing in Cheorwon, Korea) for irradiation applications. It is capable of producing 10-MeV electron beams with the 30-kW average beam power. For a high-power capability, we adopted the traveling-wave structure operated with the 2π/3-mode at 1.3 GHz. The structure is powered by a 25-MW pulsed klystron with 60-kW average RF power. The RF pulse length is 8 μs while the beam pulse length is 7 μs due to the filling time in the accelerating structure. The accelerating gradient is 4.2 MV/m at the beam current of 1.45 A which is the fully beam-loaded condition. In this paper, we present details of the accelerator system and commissioning status.