The Dynamic Coupling of Streamers and Pseudostreamers to the Heliosphere

TL;DR

This paper uses 3D magnetohydrodynamic simulations to explore how streamers and pseudostreamers interact with the heliosphere, revealing the detailed dynamics of open-closed magnetic flux interactions and their implications for space weather.

Contribution

It provides a detailed simulation-based analysis of the coupling between streamers, pseudostreamers, and the heliosphere, highlighting the role of interchange reconnection in the slow solar wind.

Findings

Interchange reconnection dominates boundary evolution.

Distinct structures form at streamer and pseudostreamer boundaries.

In situ signatures of reconnection are identified and mapped.

Abstract

The slow solar wind is generally believed to result from the interaction of open and closed coronal magnetic flux at streamers and pseudostreamers. We use 3-dimensional magnetohydrodynamic simulations to determine the detailed structure and dynamics of open-closed interactions that are driven by photospheric convective flows. The photospheric magnetic field model includes a global dipole giving rise to a streamer together with a large parasitic polarity region giving rise to a pseudostreamer that separates a satellite coronal hole from the main polar hole. Our numerical domain extends out to 30 solar radii and includes an isothermal solar wind, so that the coupling between the corona and heliosphere can be calculated rigorously. This system is driven by imposing a large set of quasi-random surface flows that capture the driving of coronal flux in the vicinity of streamer and pseudostreamer boundaries by the supergranular motions. We describe the resulting structures and dynamics. Interchange reconnection dominates the evolution at both streamer and pseudostreamer boundaries, but the details of the resulting structures are clearly different from one another. Additionally, we calculate in situ signatures of the reconnection and determine the dynamic mapping from the inner heliosphere back to the Sun for a test spacecraft orbit. We discuss the implications of our results for interpreting observations from inner heliospheric missions, such as Parker Solar Probe and Solar Orbiter, and for space weather modeling of the slow solar wind.