Co-existence of self-organized criticality and intermittent turbulence in the solar corona
Abstract
Turbulence and self-organized criticality (SOC) represent two major paths of dynamical complexity in driven, extended nonlinear systems. We present direct observational evidence for co-existence of these phenomena in the magnetized plasma of the solar corona. Using an extended collection of SOHO EIT images, we apply two alternative numerical analysis methods - one for analyzing avalanche statistics of bursty dissipation events and the other for studying spatial intermittency in the coronal emission field. We find that the energy and lifetime statistics of bursty dissipation in the corona obey robust scaling laws over the entire range of the observed scales. In contrast to previous studies of flare statistics, this observation is made using a spatiotemporal event detection algorithm compatible with the definition of avalanches in SOC simulations. Next, by applying statistical tools developed in fluid turbulence, we show that the same time series of emission patterns exhibits multiscaling and extended self-similarity of higher order structure functions characteristic of intermittent turbulence. The observed scaling behaviors show only weak dependence on average solar activity level and have been identified under both solar minimum and maximum conditions.
- Publication:
-
AGU Fall Meeting Abstracts
- Pub Date:
- December 2006
- Bibcode:
- 2006AGUFMSH13A0397U
- Keywords:
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- 4430 Complex systems;
- 4475 Scaling: spatial and temporal (1872;
- 3270;
- 4277);
- 7519 Flares;
- 7863 Turbulence (4490)