title: Full orbit calculation for lost alpha particle measurement on ITER.
abstract: An orbit following calculation code with full gyromotion under the ITER magnetic field configuration has been developed to investigate escaping alpha particle orbits in ITER and to determine the geometrical arrangement for alpha particle detection. The code contained the full geometrical information of the first wall panels. It was carefully investigated whether an alpha particle escaping from the plasma through the last closed flux surface does not touch or intersect the first wall boundary before reaching the detection point. Candidates of blanket module modification have been studied to achieve effective measurement geometry for escaping alpha particle detection. The calculations showed that direct orbit loss and banana diffusion can be detected with a probe head recessed from the first wall surface.
authors.affiliation: Department of Quantum Energy Science, Tohoku University, Sendai 980-8579, Japan. dan.funaki@ppl2.qse.tohoku.ac.jp
authors.forename: D
authors.initials: D
authors.lastname: Funaki
authors.forename: M
authors.initials: M
authors.lastname: Isobe
authors.forename: M
authors.initials: M
authors.lastname: Nishiura
authors.forename: Y
authors.initials: Y
authors.lastname: Sato
authors.forename: A
authors.initials: A
authors.lastname: Okamoto
authors.forename: T
authors.initials: T
authors.lastname: Kobuchi
authors.forename: S
authors.initials: S
authors.lastname: Kitajima
authors.forename: M
authors.initials: M
authors.lastname: Sasao