Coupling the solar dynamo and the corona: wind properties, mass and momentum losses during an activity cycle

TL;DR

This study models the solar dynamo and corona coupling over an 11-year cycle, revealing how magnetic and wind properties vary with solar activity and influence mass and momentum loss.

Contribution

It introduces a coupled 2.5D dynamo and coronal MHD simulation to analyze solar wind and magnetic field evolution during an activity cycle.

Findings

Solar wind velocity varies with latitude and time, matching observations.

Magnetic polarity reversal occurs at different rates at various coronal heights.

Mass loss rate and magnetic braking torque fluctuate significantly throughout the cycle.

Abstract

We study the connections between the sun's convection zone and the evolution of the solar wind and corona. We let the magnetic fields generated by a 2.5D axisymmetric kinematic dynamo code (STELEM) evolve in a 2.5D axisymmetric coronal isothermal MHD code (DIP). The computations cover an 11 year activity cycle. The solar wind's asymptotic velocity varies in latitude and in time in good agreement with the available observations. The magnetic polarity reversal happens at different paces at different coronal heights. Overall sun's mass loss rate, momentum flux and magnetic braking torque vary considerably throughout the cycle. This cyclic modulation is determined by the latitudinal distribution of the sources of open flux and solar wind and the geometry of the Alfv\'en surface. Wind sources and braking torque application zones also vary accordingly.