title: Three-wave interactions between fast-ion modes in the National Spherical Torus Experiment.
abstract: Simultaneous bursts of energetic particle mode (EPM) and toroidicity-induced Alfvén eigenmode (TAE) activity that correlate with significant fast-ion loss are observed in beam heated plasmas. Three-wave interactions between these modes are conclusively identified, indicating fixed phase relationships. This nonlinear coupling concentrates the energy of the TAEs into a toroidally localized perturbation frozen in the frame of a rigid, toroidally rotating structure formed by the EPMs. This redistribution of energy is significant because it will modify the effect of the TAEs on fast-ion loss.
authors.affiliation: University of California, Los Angeles, California 90095-7099, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Crocker
authors.forename: W A
authors.initials: WA
authors.lastname: Peebles
authors.forename: S
authors.initials: S
authors.lastname: Kubota
authors.forename: E D
authors.initials: ED
authors.lastname: Fredrickson
authors.forename: S M
authors.initials: SM
authors.lastname: Kaye
authors.forename: B P
authors.initials: BP
authors.lastname: LeBlanc
authors.forename: J E
authors.initials: JE
authors.lastname: Menard