Helicity Condensation as the Origin of Coronal and Solar Wind Structure

TL;DR

This paper proposes helicity condensation as a unified mechanism explaining the smooth closed corona, magnetic shear accumulation at PILs, and the structure of the slow solar wind, supported by a simplified reconnection model.

Contribution

It introduces a simplified model for helicity injection and transport, demonstrating how helicity condenses onto PILs and coronal hole boundaries, explaining key solar atmospheric features.

Findings

Helicity condenses onto PILs and coronal hole boundaries.

The model estimates helicity accumulation rates at PILs.

Results align with observed properties of the corona and solar wind.

Abstract

Three of the most important and most puzzling features of the Sun's atmosphere are the smoothness of the closed field corona, the accumulation of magnetic shear at photospheric polarity inversion lines (PIL), and the complexity of the slow wind. We propose that a single process, helicity condensation, is the physical mechanism giving rise to all three features. A simplified model is presented for how helicity is injected and transported in the closed corona by magnetic reconnection. With this model we demonstrate that helicity must condense onto PILs and coronal hole boundaries, and estimate the rate of helicity accumulation at PILs and the loss to the wind. Our results can account for many of the observed properties of the closed corona and wind.