• K. R. Kim, J.-H. Jang, M.H. Jung, S.-K. Lee
  KAERI, Daejon
• Y.M. Lee
  Kyungpook National University, Daegu
• T.K. Yang
  KIRAMS, Seoul

Funding: This work was perfomed as a part of the Proton Engineering Frontier Project and supported by the ministry of Education, Science and Technology of Korea.

A prototype LEPT(Low Energy Proton Therapy) system was developed and established at the MC-50 cyclotron in 2007. Some of the users of the PEFP (Proton Engineering Frontier Project) has been requiring a irradiation system for in-vivo experiments for the beam utilization in the fieds of medical and biological sciences. We are studying on the possibility of in-vivo experiments the prototype LEPT system. The LEPT system consists of collimators, range shifter, modulator for SOBP, dose meaurement system, etc. The energy and current from the cyclotron was 45 MeV and a few nA. For the in-vivo experiments accurate control of dose rate and penetration depth range is essential. The other important issue is how we can control the irradiation area and depth with high uniform dose distribution. We investigated the dose rate and uniformity of dose distribution inside the sample using PMMA and water phantom. The dose was measured by using ionization chamber and GAF films. The dose rate was 0.2~1Gy/sec and the penetration depth was 10~15 mm. The further studies using small animals using this LEPT system will be done by the users.

• K. R. Kim, J.-H. Jang, M.H. Jung, H.O. Kim, C.W. Lee
  KAERI, Daejon
• G.S. Chai
  Samsung SDI Co. Ltd., Gyeonggi-do
• H.J. Kim
  Kyungpook National University, Daegu
• M.K. Min
  SAMSUNG SDI CO. LTD, Gyeonggi-do

Funding: This work was performed as a part of the Proton Engineering Frontier Project supported by the Ministry of Education, Science and Technology of Korea.

The sample activation during proton beam irradiation sometimes interrupt the measurement and investigation of the instant changes of the samples after irradiation. During the experiments for nano particle fabrications with ~35MeV and ~20uA, we found that the samples was highly activated after the proton beam irradiation. To investigate the source of the rdadiation from the samples, we measured the energy spectrum of gamma ray using HPGe spectroscopy. The results was compared to the calculated results by the MCNP code simulation. The sample was small amount of heavy metal dispersed in enthanol in the beaker made of quartz.

• M.-H. Chun, M.H. Jung, I.S. Park, Y.U. Sohn, I.H. Yu
  PAL, Pohang, Kyungbuk

Funding: Supported by the Korea Ministry of Science and Technology mhchun@postech.ac.kr

The RF system for the Pohang Light Source (PLS) storage ring is operating at total maximum RF power of 300kW with four 75kW klystron amplifiers and four PF-type normal conductivity(NC) RF cavities for 190mA at 2.5GeV. The PLS will be upgraded from 2.5GeV/200mA to 3.0GeV/400mA in the near future. Therefore the RF system should be greatly upgraded to supply total 627kW beam power. We are investigated the some upgrade ways with adding NC cavities or new super conductivity(SC) RF cavities. According to the cavity type, the high power RF system will be adjusted the total RF power, and source type and quantity such as klystron or IOT. This paper describes the present operation status and several optional ways of high power RF system for the upgrade project of PLS storage ring