Magnetic field amplification and structure formation by the Rayleigh-Taylor instability

TL;DR

This study uses high-resolution two-fluid simulations to explore how the Rayleigh-Taylor instability in solar prominences amplifies magnetic fields and forms complex structures, highlighting the roles of ionization, flow decoupling, and magnetic energy conversion.

Contribution

It presents detailed 2.5D magnetized RTI simulations incorporating ionization, recombination, and two-fluid effects, revealing magnetic energy amplification and structure formation mechanisms.

Findings

Large fraction of gravitational energy converts into magnetic energy.

Formation and merging of current sheets and plasmoid sub-structures.

Ionization and flow decoupling significantly influence structure formation.

Abstract

We report on results of high resolution two fluid non-linear simulations of the Rayleigh Taylor Instability (RTI) at the interface between a solar prominence and the corona. These follow results reported earlier by Popescu Braileanu et al. (2021a,b) on linear and early non-linear RTI dynamics in this environment. The simulations use a two fluid model that includes collisions between neutrals and charges, including ionization/recombination, energy and momentum transfer, and frictional heating. High resolution 2.5D magnetized RTI simulations with the magnetic field dominantly normal to and slightly sheared with respect to the prominence plane demonstrate that in a fully developed state of RTI a large fraction of the gravitational energy of a prominence thread can be converted into quasi-turbulent energy of the magnetic field. RTI magnetic energy generation is further accompanied by magnetic and plasma density structure formation, including dynamic formation, break-up, and merging of current sheets and plasmoid sub-structures. The simulations show the role of flow decoupling and ionization/recombination reactions between the neutrals and charges on the structure formation in magnetized RTI. We provide a careful examination of sources and form of numerical dissipation of the evolving magnetic field structures.