Topside Reconnection

TL;DR

This paper proposes that magnetic reconnection in the topside ionosphere's current sheets is a key process influencing plasma dynamics, generating anomalous diffusivity without significantly altering the ambient magnetic field.

Contribution

It introduces the concept that reconnection occurs in the topside ionosphere's narrow current sheets, highlighting its role in plasma processes and anomalous diffusivity.

Findings

Reconnection occurs between closely spaced downward current sheets.

It generates anomalous diffusivity in the plasma.

It does not significantly affect the ambient magnetic field.

Abstract

It is proposed that reconnection would be a main mechanism governing the plasma processes on auroral time scales in the topside ionosphere/high-latitude magnetosphere transition. It occurs in the downward current region between two narrow parallel closely spaced though separated downward current sheets. The field-aligned currents are carried by upward cold upper-ionospheric electrons closing the upward current in an adjacent region. This local process does primarily not affect the ambient field but generates an anomalous diffusivity.