# Diagnosing collisionless energy transfer using field-particle correlations: gyrokinetic turbulence

## TL;DR

This paper demonstrates that field-particle correlations applied to gyrokinetic turbulence simulations can identify collisionless energy transfer mechanisms, paving the way for analyzing spacecraft data to understand plasma turbulence dissipation.

## Contribution

It extends the use of field-particle correlations to strongly driven gyrokinetic turbulence, confirming their effectiveness in identifying collisionless damping mechanisms.

## Key findings

- Correlation velocity-space structure matches resonant energy transfer mechanisms.
- Technique successfully applied to simulation data for collisionless damping detection.
- Supports future application to spacecraft measurements in the solar wind.

## Abstract

Determining the physical mechanisms that extract energy from turbulent fluctuations in weakly collisional magnetized plasmas is necessary for a more complete characterization of the behavior of a variety of space and astrophysical plasmas. Such a determination is complicated by the complex nature of the turbulence as well as observational constraints, chiefly that in situ measurements of such plasmas are typically only available at a single point in space. Recent work has shown that correlations between electric fields and particle velocity distributions constructed from single-point measurements produce a velocity-dependent signature of the collisionless damping mechanism. We extend this work by constructing field-particle correlations using data sets drawn from single points in strongly driven, turbulent, electromagnetic gyrokinetic simulations to demonstrate that this technique can identify the collisionless mechanisms operating in such systems. The correlation's velocity-space structure agrees with expectations of resonant mechanisms transferring energy collisionlessly in turbulent systems. This work motivates the eventual application of field-particle correlations to spacecraft measurements in the solar wind, with the ultimate goal to determine the physical mechanisms that dissipate magnetized plasma turbulence.