Ensemble Space-Time Correlation of Plasma Turbulence in the Solar Wind

Single point measurement turbulence cannot distinguish variations in space and time. We employ an ensemble of one- and two-point measurements in the solar wind to estimate the space-time correlation function in the comoving plasma frame. The method is illustrated using near Earth spacecraft observat...

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Autores principales: Matthaeus, W.H., Weygand, J.M., Dasso, S.
Formato: JOUR
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Acceso en línea:http://hdl.handle.net/20.500.12110/paper_00319007_v116_n24_p_Matthaeus
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Sumario:Single point measurement turbulence cannot distinguish variations in space and time. We employ an ensemble of one- and two-point measurements in the solar wind to estimate the space-time correlation function in the comoving plasma frame. The method is illustrated using near Earth spacecraft observations, employing ACE, Geotail, IMP-8, and Wind data sets. New results include an evaluation of both correlation time and correlation length from a single method, and a new assessment of the accuracy of the familiar frozen-in flow approximation. This novel view of the space-time structure of turbulence may prove essential in exploratory space missions such as Solar Probe Plus and Solar Orbiter for which the frozen-in flow hypothesis may not be a useful approximation. © 2016 American Physical Society.