title: Vacuum insulation of the high energy negative ion source for fusion application.
abstract: Vacuum insulation on a large size negative ion accelerator with multiple extraction apertures and acceleration grids for fusion application was experimentally examined and designed. In the experiment, vacuum insulation characteristics were investigated in the JT-60 negative ion source with >1000 apertures on the grid with the surface area of ∼2 m(2). The sustainable voltages varied with a square root of the gap lengths between the grids, and decreased with number of the apertures and with the surface area of the grids. Based on the obtained results, the JT-60SA (super advanced) negative ion source is designed to produce 22 A, 500 keV D(-) ion beams for 100 s.
authors.affiliation: Japan Atomic Energy Agency, Naka, Ibaraki 311-0193, Japan. kojima.atsushi@jaea.go.jp
authors.forename: A
authors.initials: A
authors.lastname: Kojima
authors.forename: M
authors.initials: M
authors.lastname: Hanada
authors.forename: A
authors.initials: A
authors.lastname: Hilmi
authors.forename: T
authors.initials: T
authors.lastname: Inoue
authors.forename: K
authors.initials: K
authors.lastname: Watanabe
authors.forename: M
authors.initials: M
authors.lastname: Taniguchi
authors.forename: M
authors.initials: M
authors.lastname: Kashiwagi
authors.forename: N
authors.initials: N
authors.lastname: Umeda
authors.forename: H
authors.initials: H
authors.lastname: Tobari
authors.forename: S
authors.initials: S
authors.lastname: Kobayashi
authors.forename: Y
authors.initials: Y
authors.lastname: Yamano
authors.forename: L R
authors.initials: LR
authors.lastname: Grisham