Characterizing the Velocity-Space Signature of Electron Landau Damping

TL;DR

This paper uses gyrokinetic turbulence simulations and the field-particle correlation technique to identify and characterize the velocity-space signatures of electron Landau damping across different plasma beta conditions, aiding interpretation of spacecraft data.

Contribution

It provides a detailed analysis of electron Landau damping signatures in turbulent plasmas with varying beta, advancing understanding of plasma heating mechanisms.

Findings

Key features of velocity-space signatures identified

Signatures vary systematically with plasma beta

Framework established for interpreting spacecraft observations

Abstract

Plasma turbulence plays a critical role in the transport of energy from large-scale magnetic fields and plasma flows to small scales, where the dissipated turbulent energy ultimately leads to heating of the plasma species. A major goal of the broader heliophysics community is to identify the physical mechanisms responsible for the dissipation of the turbulence and to quantify the consequent rate of plasma heating. One of the mechanisms proposed to damp turbulent fluctuations in weakly collisional space and astrophysical plasmas is electron Landau damping. The velocity-space signature of electron energization by Landau damping can be identified using the recently developed field-particle correlation technique. Here, we perform a suite of gyrokinetic turbulence simulations with ion plasma beta values of 0.01, 0.1, 1, and 10 and use the field-particle correlation technique to characterize the features of the velocity-space signatures of electron Landau damping in turbulent plasma conditions consistent with those observed in the solar wind and planetary magnetospheres. We identify the key features of the velocity-space signatures of electron Landau damping as a function of varying plasma \beta_i to provide a critical framework for interpreting the results of field-particle correlation analysis of in situ spacecraft observations of plasma turbulence.