• Burst statistics of fluctuations in a simple magnetized torus configuration 

      Rypdal, Kristoffer; Živkovic, Tatjana; Østvand, Lene (Working paper; Arbeidsnotat, 2009-04-19)
      In a toroidal plasma confined by a purely toroidal magnetic field the plasma transport is governed by electrostatic turbulence driven by the flute interchange instability on the low-field side of the torus cross section. In this paper we revisit experimental data obtained from the Blaamann torus at the University of Tromso. On time-scales shorter than the poloidal rotation time, the time series of ...
    • Complexity in plasma and geospace systems 

      Živkovic, Tatjana (Doctoral thesis; Doktorgradsavhandling, 2011-05-10)
      The subject of this thesis is self-organization, chaos and stochastic dynamics in laboratory plasmas, the magnetosphere, and in the Earth's climate system. For each of these systems we pose the question whether the global dynamics can be described by a set of a few variables governed by the same small number of deterministic equations. This problem is not trivial, because low-dimensional ...
    • Evidence of low-dimensional chaos in magnetized plasma turbulence 

      Živkovic, Tatjana; Rypdal, Kristoffer (Working paper; Arbeidsnotat, 2008-03-10)
      We analyze probe data obtained from a toroidal magnetized plasma configuration suitable for studies of low-frequency gradient-driven instabilities. These instabilities give rise to field-aligned convection rolls analogous to Rayleigh-Benard cells in neutral fluids, and may theoretically develop similar routes to chaos. When using mean-field dimension analysis, we observe low dimensionality, but ...