Two-fluid simulations of Rayleigh-Taylor instability in a magnetized solar prominence thread. I. Effects of prominence magnetization and mass loading. (arXiv:2007.15984v1 [astro-ph.SR])
<a href="http://arxiv.org/find/astro-ph/1/au:+Braileanu_B/0/1/0/all/0/1">B. Popescu Braileanu</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Lukin_V/0/1/0/all/0/1">V. S. Lukin</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Khomenko_E/0/1/0/all/0/1">E. Khomenko</a>, <a href="http://arxiv.org/find/astro-ph/1/au:+Vicente_A/0/1/0/all/0/1">A. de Vicente</a>
Solar prominences are formed by partially ionized plasma with inter-particle
collision frequencies generally warranting magnetohydrodynamic treatment. In
this work, we explore the dynamical impacts and observable signatures of
two-fluid effects in the parameter regimes when ion-neutral collisions do not
fully couple the neutral and charged fluids. We perform 2.5D two-fluid (charges
– neutrals) simulations of the Rayleigh-Taylor instability (RTI) at a smoothly
changing interface between a solar prominence thread and the corona. The
purpose of this study is to deepen our understanding of the RTI and the effects
of the partial ionization on the development of RTI using non-linear two-fluid
numerical simulations. Our two-fluid model takes into account viscosity,
thermal conductivity, and collisional interaction between neutrals and charges:
ionization/recombination, energy and momentum transfer, and frictional heating.
In this paper I, the sensitivity of the RTI dynamics to the prominence
equilibrium configuration, including the impact of the magnetic field strength
and shear supporting the prominence thread, and the amount of prominence
mass-loading is explored. We show that, at small scales, a realistically smooth
prominence-corona interface leads to qualitatively different linear RTI
evolution than that expected for a discontinuous interface, while magnetic
field shear has the stabilizing effect of reducing the growth rate or
eliminating the instability. In the non-linear phase, we observe that in the
presence of field shear the development of the instability leads to formation
of coherent and interacting 2.5D magnetic structures, which, in turn, can lead
to substantial plasma flow across magnetic field lines and associated
decoupling of the fluid velocities of charges and neutrals.
Solar prominences are formed by partially ionized plasma with inter-particle
collision frequencies generally warranting magnetohydrodynamic treatment. In
this work, we explore the dynamical impacts and observable signatures of
two-fluid effects in the parameter regimes when ion-neutral collisions do not
fully couple the neutral and charged fluids. We perform 2.5D two-fluid (charges
– neutrals) simulations of the Rayleigh-Taylor instability (RTI) at a smoothly
changing interface between a solar prominence thread and the corona. The
purpose of this study is to deepen our understanding of the RTI and the effects
of the partial ionization on the development of RTI using non-linear two-fluid
numerical simulations. Our two-fluid model takes into account viscosity,
thermal conductivity, and collisional interaction between neutrals and charges:
ionization/recombination, energy and momentum transfer, and frictional heating.
In this paper I, the sensitivity of the RTI dynamics to the prominence
equilibrium configuration, including the impact of the magnetic field strength
and shear supporting the prominence thread, and the amount of prominence
mass-loading is explored. We show that, at small scales, a realistically smooth
prominence-corona interface leads to qualitatively different linear RTI
evolution than that expected for a discontinuous interface, while magnetic
field shear has the stabilizing effect of reducing the growth rate or
eliminating the instability. In the non-linear phase, we observe that in the
presence of field shear the development of the instability leads to formation
of coherent and interacting 2.5D magnetic structures, which, in turn, can lead
to substantial plasma flow across magnetic field lines and associated
decoupling of the fluid velocities of charges and neutrals.
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