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Turbulence Signatures in the Polar/Cusp Ionosphere during ICI-mission flights

Francesca Di Mare - University of Oslo; Andres Spicher - University of Oslo, Norway; Lasse B.N. Clausen - University of Oslo, Norway; Wojciech J. Miloch - University of Oslo, Norway; Jøran I. Moen - University of Oslo, Norway

Thermosphere-ionosphere interactions and effects (II)

Abstract

Turbulent plasma observations from the Investigation of Cusp Irregularities-ICI sounding rocket missions are the objective of this study. We report methods based on cross-correlation between the signals that reveal information regarding the scales involved, the level of turbulence in the fluctuations observed, and a quantitative measurement of the intermittency developed. The electron density fluctuations from ICI-2 and ICI-3 missions have been analysed using time-series analysis techniques and standard diagnostics for intermittent turbulence. The following parameters have been obtained: the autocorrelation function that gives information about the correlation scale of the field (Pope 2000); the associated energy power spectrum in which a power-law scaling exponent not far from the Kolmogorov value −5/3 is obtained at MHD scales (Leamon 1998), while a steeper power law is suggested below kinetic scales (Sahraoui 2006). The presence of turbulent structures is observed in the Probability Distribution Functions (PDFs) (Frisch 1995, Sreenivasan 1999, Bruno 2005)  by means of the deviation from Gaussian of the scale-dependent increments towards small scales due to intense field fluctuations. Finally the analysis of kurtosis allows to suggest the presence of intermittency (Anselmet 1984, Sreenivasan 1994) in agreement with the presence of small scale intermittent structures observed in the LIM.

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Approaching deadlines:

Registration opens:

16 July 2020

Abstract submission opens:

16 July 2020

European Space Weather Medals:

6 September 2020

Registration deadline:

25 September 2020

Registration deadline: [extended]

10 October 2020

Abstract submission deadline:

4 September 2020