title: Physical mechanism behind zonal-flow generation in drift-wave turbulence.
abstract: The energetic interaction between drift-wave turbulence and zonal flows is studied experimentally in two-dimensional wave number space. The kinetic energy is found to be transferred nonlocally from the drift waves to the zonal flow. This confirms the theoretical prediction that the parametric-modulational instability is the driving mechanism of zonal flows. The physical mechanism of this nonlocal energetic interaction between and zonal flows and turbulent drift-wave eddies in relation to the suppression of turbulent transport is discussed.
authors.affiliation: Institut für Plasmaforschung, Universität Stuttgart, D-70569 Stuttgart, Germany.
authors.forename: P
authors.initials: P
authors.lastname: Manz
authors.forename: M
authors.initials: M
authors.lastname: Ramisch
authors.forename: U
authors.initials: U
authors.lastname: Stroth