title: Alpha-tail production with ion-cyclotron-resonance heating of 4He-beam ions in JET plasmas.
abstract: Third-harmonic ion-cyclotron-resonance heating of 4He-beam ions has produced for the first time on the JET tokamak high-energy populations of 4He ions to simulate 3.5 MeV fusion-born alpha (alpha) particles. Acceleration of 4He ions to the MeV energy range is confirmed by gamma-ray emission from the nuclear reaction 9Be(alpha,ngamma) 12C and excitation of Alfvén eigenmodes. Concomitant electron heating and sawtooth stabilization are observed. The scheme could be used in next-step tokamaks to gain information on trapped alpha particles and to test alpha diagnostics in the early nonactivated phase of operation.
authors.affiliation: Helsinki University of Technology, Association Euratom-Tekes, Finland.
authors.forename: M J
authors.initials: MJ
authors.lastname: Mantsinen
authors.forename: M-L
authors.initials: ML
authors.lastname: Mayoral
authors.forename: V G
authors.initials: VG
authors.lastname: Kiptily
authors.forename: S E
authors.initials: SE
authors.lastname: Sharapov
authors.forename: B
authors.initials: B
authors.lastname: Alper
authors.forename: A
authors.initials: A
authors.lastname: Bickley
authors.forename: M
authors.initials: M
authors.lastname: de Baar
authors.forename: L-G
authors.initials: LG
authors.lastname: Eriksson
authors.forename: A
authors.initials: A
authors.lastname: Gondhalekar
authors.forename: T
authors.initials: T
authors.lastname: Hellsten
authors.forename: K
authors.initials: K
authors.lastname: Lawson
authors.forename: F
authors.initials: F
authors.lastname: Nguyen
authors.forename: J-M
authors.initials: JM
authors.lastname: Noterdaeme
authors.forename: E
authors.initials: E
authors.lastname: Righi
authors.forename: A A
authors.initials: AA
authors.lastname: Tuccillo
authors.forename: M
authors.initials: M
authors.lastname: Zerbini