Coronal Inflows and Giant Polar Plumes

TL;DR

This paper presents 2.5D MHD simulations of giant polar plumes and coronal flows, revealing how Alfvén wave perturbations influence plume formation in the solar corona.

Contribution

It introduces a novel 2.5D axisymmetric MHD model to simulate giant polar plumes driven by Alfvén waves, advancing understanding beyond previous 1D models.

Findings

Plumes form above small magnetic bipoles in the corona.

Alfvén waves perturb the unipolar flux region, influencing plume dynamics.

Simulation results align qualitatively with earlier 1D wind models.

Abstract

We present the first results of simulations of giant polar plumes and coronal flows. We use a 2.5D axisymmetric MHD numerical model of an isothermal corona and slow solar wind. A plume is generated just above asmall magnetic bipole embedded in an unipolar flux region which is perturbed by Alfv\'en waves injected from the coronal base. The boundary conditions are transparent. The results are compared to those obtained previously with a 1D wind model in which plumes are generated as a consequence of variations of the heating and flux-tube expansion parameters.