Effect of filter scale and plasma beta on anomalous electric-field contributions

Determine how increasing the filter scale affects the contribution of the total anomalous electric field to the total filtered electric field for plasmas with different ion plasma beta values.

Background

The simulations show that increasing the filter scale transfers more turbulent energy from the resolved fields into anomalous terms. However, the anomalous contribution does not increase linearly with filter scale, and its phase relationship with the resolved electric field varies across the three ion plasma beta cases.

Consequently, the magnitude of the anomalous terms alone does not determine their dynamical importance in the total filtered electric field. Resolving this dependence is relevant for constructing sub-grid-scale closures that remain valid across different plasma regimes and filter scales.

References

Although it is clear that increasing $\Delta_{c}$ leads to more energy stored in the anomalous terms, it is not clear how this affects the contribution from the anomalous term to the total filtered electric field for the different $\beta_{i}$ cases.

— Anomalous Electric Fields in Earth's Turbulent Magnetosheath: Insights From 3D Hybrid Simulations  (2608.24326 - Rueda et al., 25 Aug 2026) in Section 3.2, Relative Importance of the Filtered and Anomalous Terms