The properties of turbulence in Earth's magnetosheath and their influence on small-scale magnetic reconnection events
Abstract
Earth's magnetosheath is filled with complex, nonlinear fluctuations known as turbulence that generate a multitude of small-scale current sheets. A number of previous studies have shown that these current sheets are potential locations for magnetic reconnection and that in some cases the reconnection events may occur without forming ion jets - so-called electron-only magnetic reconnection. However, the general impact of the reconnection events within the turbulent plasma remains an open question. In this study, we perform a detailed survey of ~60 intervals of magnetosheath turbulence observed with high-resolution, multi-spacecraft measurements from the Magnetospheric Multiscale (MMS) mission across the subsolar region and into the flanks. Within each interval characteristic properties of the turbulence (e.g., correlation length, spectral shape) are determined and several hundred individual magnetic reconnection events are identified, including both reconnection events with and without ion jets. Evidence of magnetic reconnection is found in nearly all of the turbulent intervals examined, and the properties of the reconnection events are explored in the context of the turbulence properties of the intervals. A spectral break is found in the magnetic spectrum at ~4 electron inertial lengths (0.1 ion inertial lengths) consistent with the typical thickness of reconnecting current sheets and the relationship between this spectral feature and the current sheets is explored. The results demonstrate that magnetic reconnection may be a common feature in turbulent plasmas such as Earth's magnetosheath and, by systematically characterising the properties of these reconnection events, provide crucial insight needed to determine the potential impact of reconnection on the nonlinear dynamics and turbulent dissipation.
- Publication:
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AGU Fall Meeting Abstracts
- Pub Date:
- December 2020
- Bibcode:
- 2020AGUFMSH020..05S
- Keywords:
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- 2134 Interplanetary magnetic fields;
- INTERPLANETARY PHYSICS;
- 2149 MHD waves and turbulence;
- INTERPLANETARY PHYSICS;
- 2164 Solar wind plasma;
- INTERPLANETARY PHYSICS;
- 7827 Kinetic and MHD theory;
- SPACE PLASMA PHYSICS;
- 7839 Nonlinear phenomena;
- SPACE PLASMA PHYSICS;
- 7863 Turbulence;
- SPACE PLASMA PHYSICS