Impulsively Generated Kink Wave Trains in Solar Coronal Slabs

TL;DR

This study uses numerical simulations within ideal MHD to analyze how impulsive transverse velocity perturbations generate kink wave trains in solar coronal slabs, revealing nonlinear effects like density cavities and shocks relevant to solar phenomena.

Contribution

It provides the first detailed numerical analysis of kink wave trains in coronal slabs, including nonlinear effects such as shocks and density cavities, enhancing understanding of solar coronal dynamics.

Findings

Kink wave trains develop with increasing oscillatory patterns over time.

Nonlinear effects include density cavities and shock formations.

Results relate to observed streamer waves in the solar corona.

Abstract

We numerically follow the response of density-enhanced slabs to impulsive, localized, transverse velocity perturbations by working in the framework of ideal magnetohydrodynamics (MHD). Both linear and nonlinear regimes are addressed. Kink wave trains are seen to develop along the examined slabs, sharing the characteristics that more oscillatory patterns emerge with time and that the apparent wavelength increases with distance at a given instant. Two features nonetheless arise due to nonlinearity, one being a density cavity close to the exciter and the other being the appearance of shocks both outside and inside the nominal slab. These features may be relevant for understanding the interaction between magnetic structures and such explosive events as coronal mass ejections. Our numerical findings on kink wave trains in solar coronal slabs are discussed in connection with typical measurements of streamer waves.