Relationship between Current Filaments and Turbulence During a Turbulent Reconnection

Abstract

Both magnetic reconnection and turbulence can play crucial roles in space plasmas. The current layers, developing during magnetic reconnection, can collapse into various small-scale coherent structures, such as current filaments. These current filaments can significantly modulate the kinetic-scale turbulence. However, the quantitative correlation between the current filaments and turbulence remains unknown so far. In this study, we statistically analyze such a relation during a turbulent reconnection in the magnetotail. We find that the kinetic-scale turbulence has a good correlation with the current-density variation ≤ft({J}^{\prime }=≤ft|\tfrac{{dJ}}{{dt}}\right|\right). Specifically, (1) the slope of the kinetic-scale power spectral density (PSD), denoted as S _PSD, decreases with J‧, exhibiting an empirical relation S _PSD = -0.54ln(J‧) - 1.36; (2) the correlation between turbulence intensity (PSD) and J‧ is best at the frequency range 0.02-0.32 ω _ce (electron cyclotron frequency); (3) the turbulence intensity (PSD) increases with J‧, exhibiting an empirical relation PSD = J‧ ^k • e ^b ; and (4) the k of these fitting functions roughly decreases with frequency. These results can advance our understanding of the interplay between magnetic reconnection and turbulence.