Generalized similarity in magnetohydrodynamic turbulence as seen in the solar corona and solar wind
Abstract
A key property of turbulence is that it can be characterized and quantified in a robust and reproducible way in terms of the ensemble averaged statistical properties of fluctuations. Importantly, fluctuations associated with a turbulent field show similarity or scaling in their statistics and we test for this in observations of magnetohydrodynamic turbulence in the solar corona and solar wind with both power spectra and Generalized Structure Functions. Realizations of turbulence that are finite sized are known to exhibit a generalized or extended self-similarity (ESS). ESS was recently demonstrated in magnetic field timeseries of Ulysses single point in-situ observations of fluctuations of quiet solar wind for which a single robust scaling function was found [1-2]. Flows in solar coronal prominences can be highly variable, with dynamics suggestive of turbulence. The Hinode SOT instrument provides observations (images) at simultaneous high spatial and temporal resolution which span several decades in both spatial and temporal scales. We focus on specific Calcium II H-line observations of solar quiescent prominences with dynamic, highly variable small-scale flows. We analyze these images from the perspective of a finite sized turbulent flow. We discuss this evidence of ESS in the SOT images and in Ulysses solar wind observations- is there a single universal scaling of the largest eddies in the finite range magnetohydrodynamic turbulent flow? [1] S. C. Chapman, R. M. Nicol, Generalized Similarity in Finite Range Solar Wind Magnetohydrodynamic Turbulence, Phys. Rev. Lett., 103, 241101 (2009) [2] S. C. Chapman, R. M. Nicol, E. Leonardis, K. Kiyani, V. Carbone, Observation of universality in the generalized similarity of evolving solar wind turbulence as seen by ULYSSES, Ap. J. Letters, 695, L185, (2009)
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2010
- Bibcode:
- 2010AGUFMNG51B1211C
- Keywords:
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- 2159 INTERPLANETARY PHYSICS / Plasma waves and turbulence;
- 2164 INTERPLANETARY PHYSICS / Solar wind plasma;
- 4490 NONLINEAR GEOPHYSICS / Turbulence;
- 7863 SPACE PLASMA PHYSICS / Turbulence