JOURNAL OF THE KOREAN PHYSICAL SOCIETY, v.82, no.12, pp.1231 - 1239
Abstract
This study proposes a method to reduce the beamline pollution caused by lithium gas generated when a lithium film is formed while driving a heavy ion accelerator. To this end, the liquefaction and solidification of lithium vapor are utilized, and a skimmer is installed on the beamline to reduce pollution through contact with lithium vapor. Particularly, three curved skimmers were installed in consideration of the length of the beamline to increase the contact area. Analysis results revealed that the lithium film forms lithium gas at 0.5 g/s. When the gas flow generated is converted into a vacuum pump, the vacuum degree of the beam line is 3.88 x 10(-7) mbar, which is 1/74 of the vacuum degree of the charge stripper, and approximately 30% lower than that of a straight-type skimmer. Additionally, the flow velocity of lithium particle is 3 x 10(-11) m/s, and it takes 1260 years to reach the beamline; accordingly, the results suggest that the use of a curved skimmer will enable the optimal operation of the beamline without any lithium contamination.