Finding the mechanism of wave energy flux damping in solar pores using numerical simulations

TL;DR

This study uses 2D MHD simulations to explore the damping mechanisms of wave energy flux in solar pores, identifying geometric spreading and wave leakage as key factors in observed energy attenuation.

Contribution

It introduces a numerical approach with localized drivers to explain wave damping in solar pores, highlighting geometric effects as primary causes.

Findings

Localized driver simulations match observed damping.

Geometric spreading causes energy flux reduction.

Lateral wave leakage contributes to damping.

Abstract

Context. Solar magnetic pores are, due to their concentrated magnetic fields, suitable guides for magnetoacoustic waves. Recent observations have shown that propagating energy flux in pores is subject to strong damping with height; however, the reason is still unclear. Aims. We investigate possible damping mechanisms numerically to explain the observations. Methods. We performed 2D numerical magnetohydrodynamic (MHD) simulations, starting from an equilibrium model of a single pore inspired by the observed properties. Energy was inserted into the bottom of the domain via different vertical drivers with a period of 30s. Simulations were performed with both ideal MHD and non-ideal effects. Results. While the analysis of the energy flux for ideal and non-ideal MHD simulations with a plane driver cannot reproduce the observed damping, the numerically predicted damping for a localized driver closely corresponds with the observations. The strong damping in simulations with localized driver was caused by two geometric effects, geometric spreading due to diverging field lines and lateral wave leakage.