title: Long pulse beam extraction with a prototype ion source for the KSTAR neutral beam system.
abstract: Long pulse operational characteristics of the high current ion source for the KSTAR neutral beam system are described. The beam pulse length of 300 s was successfully operated at a beam power of 1.6 MW with a beam energy of 70 keV. Beam energy, beam current, beam divergence, arc power, and several other operational parameters were measured during a pulse to analyze the long pulse properties. The increase of the cooling water temperature of the accelerator grids and plasma generator components were measured by water flow calorimetric system using thermocouples. The temperature rises of the filament electrodes of the ion source and the G1 grids (plasma grids) of the accelerator turned out to be the critical factors of the long pulse operation in the current system.
authors.affiliation: Korea Atomic Energy Research Institute, Daejeon, Korea.
authors.forename: Byung-Hoon
authors.initials: BH
authors.lastname: Oh
authors.forename: Doo-Hee
authors.initials: DH
authors.lastname: Chang
authors.forename: Seung Ho
authors.initials: SH
authors.lastname: Jeong
authors.forename: Kwang-Won
authors.initials: KW
authors.lastname: Lee
authors.forename: Sang-Ryul
authors.initials: SR
authors.lastname: In
authors.forename: Byung-Joo
authors.initials: BJ
authors.lastname: Yoon
authors.forename: Min-Seok
authors.initials: MS
authors.lastname: Seo
authors.forename: Jung-Tae
authors.initials: JT
authors.lastname: Jin
authors.forename: Bum-Ryul
authors.initials: BR
authors.lastname: Kim
authors.forename: Dae-Sik
authors.initials: DS
authors.lastname: Chang
authors.forename: Ki-Sok
authors.initials: KS
authors.lastname: Jung
authors.forename: Jinchoon
authors.initials: J
authors.lastname: Kim
authors.forename: Tae-Seong
authors.initials: TS
authors.lastname: Kim
authors.forename: Young Soon
authors.initials: YS
authors.lastname: Bae