Search Publications
Lagrangian chaotic saddles and objective vortices in solar plasmas
Chian, Abraham C. -L.; Park, Sung-Hong; Kusano, Kanya +4 more
We report observational evidence of Lagrangian chaotic saddles in plasmas, given by the intersections of finite-time unstable and stable manifolds, using an ≈22 h sequence of spacecraft images of the horizontal velocity field of solar photosphere. A set of 29 persistent objective vortices with lifetimes varying from 28.5 to 298.3 min are detected …
Time series with tailored nonlinearities
Räth, C.; Laut, I.
It is demonstrated how to generate time series with tailored nonlinearities by inducing well-defined constraints on the Fourier phases. Correlations between the phase information of adjacent phases and (static and dynamic) measures of nonlinearities are established and their origin is explained. By applying a set of simple constraints on the phase…
Diagnosis of magnetic structures and intermittency in space-plasma turbulence using the technique of surrogate data
Sahraoui, F.
Intermittency is usually identified in turbulent flows as non-Gaussian tails of the probability density functions (PDFs) of the turbulent field derivatives. Here we investigate the role of phase coherence among the Fourier modes in creating intermittency in magnetized space plasmas using the technique of surrogate data. We apply the technique to t…