Evaluation of scale-dependent kurtosis with HelioSwarm

TL;DR

This paper demonstrates that higher-order statistical measures like kurtosis can be accurately obtained from multipoint spacecraft data, enhancing the study of plasma turbulence across scales, with implications for upcoming missions like HelioSwarm.

Contribution

It introduces a method to reliably measure scale-dependent kurtosis using synthetic turbulence and applies it to HelioSwarm's planned trajectories, advancing turbulence analysis techniques.

Findings

Kurtosis can be accurately measured across multiple scales.

Synthetic turbulence tests validate the method's effectiveness.

Application to HelioSwarm trajectories shows potential for turbulence insights.

Abstract

Plasma turbulence involves complex, nonlinear interactions of electromagnetic fields and charged particles across multiple scales. Studying these phenomena in space plasmas, like the solar wind, is facilitated by the intrinsic scale separations and the availability of in situ spacecraft observations. However, the single-point or single-scale configurations of current spacecraft limit our understanding of many properties of the turbulent solar wind. To overcome these limitations, multipoint measurements spanning a range of characteristic scales are essential. This paper prepares for the enhanced measurement capabilities of upcoming multispacecraft missions by demonstrating that higher-order statistics, specifically kurtosis, as a baseline for intermittency can be accurately measured. Using synthetic turbulent fields with adjustable intermittency levels, we achieve scale separations analogous to those in the solar wind and apply these techniques to the planned trajectories of the HelioSwarm mission. This approach promises significant advancements in our understanding of plasma turbulence.