title: Influence of magnetic field ripple on the intrinsic rotation of tokamak plasmas.
abstract: Using the unique capability of JET to monotonically change the amplitude of the magnetic field ripple, without modifying other relevant equilibrium conditions, the effect of the ripple on the angular rotation frequency of the plasma column was investigated under the conditions of no external momentum input. The ripple amplitude was varied from 0.08% to 1.5% in Ohmic and ion-cyclotron radio-frequency (ICRF) heated plasmas. In both cases the ripple causes counterrotation, indicating a strong torque due to nonambipolar transport of thermal ions and in the case of ICRF also fast ions.
authors.affiliation: Associação EURATOM/IST, Instituto de Plasmas e Fusão Nuclear-Laboratorio Associado, Lisbon, Portugal.
authors.forename: M F F
authors.initials: MF
authors.lastname: Nave
authors.forename: T
authors.initials: T
authors.lastname: Johnson
authors.forename: L-G
authors.initials: LG
authors.lastname: Eriksson
authors.forename: K
authors.initials: K
authors.lastname: Crombé
authors.forename: C
authors.initials: C
authors.lastname: Giroud
authors.forename: M-L
authors.initials: ML
authors.lastname: Mayoral
authors.forename: J
authors.initials: J
authors.lastname: Ongena
authors.forename: A
authors.initials: A
authors.lastname: Salmi
authors.forename: T
authors.initials: T
authors.lastname: Tala
authors.forename: M
authors.initials: M
authors.lastname: Tsalas