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Title: Multi-fluid Modeling of Magnetosonic Wave Propagation in the Solar Chromosphere: Effects of Impact Ionization and Radiative Recombination

Abstract

In order to study chromospheric magnetosonic wave propagation including, for the first time, the effects of ion–neutral interactions in the partially ionized solar chromosphere, we have developed a new multi-fluid computational model accounting for ionization and recombination reactions in gravitationally stratified magnetized collisional media. The two-fluid model used in our 2D numerical simulations treats neutrals as a separate fluid and considers charged species (electrons and ions) within the resistive MHD approach with Coulomb collisions and anisotropic heat flux determined by Braginskiis transport coefficients. The electromagnetic fields are evolved according to the full Maxwell equations and the solenoidality of the magnetic field is enforced with a hyperbolic divergence-cleaning scheme. The initial density and temperature profiles are similar to VAL III chromospheric model in which dynamical, thermal, and chemical equilibrium are considered to ensure comparison to existing MHD models and avoid artificial numerical heating. In this initial setup we include simple homogeneous flux tube magnetic field configuration and an external photospheric velocity driver to simulate the propagation of MHD waves in the partially ionized reactive chromosphere. In particular, we investigate the loss of chemical equilibrium and the plasma heating related to the steepening of fast magnetosonic wave fronts in the gravitationally stratifiedmore » medium.« less

Authors:
; ;  [1];  [2]
  1. Department of Mathematics, Center for Mathematical Plasma Astrophysics, Catholic University of Leuven, B-3001 Leuven (Belgium)
  2. von Karman Institute for Fluid Dynamics, CFD group, Aeronautics and Aerospace, Rhode Saint-Genèse (Belgium)
Publication Date:
OSTI Identifier:
22663774
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 836; Journal Issue: 2; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; ANISOTROPY; CHROMOSPHERE; COLLISIONS; COMPUTERIZED SIMULATION; ELECTROMAGNETIC FIELDS; HEAT FLUX; IONIZATION; LOSSES; MAGNETIC FIELD CONFIGURATIONS; MAGNETIC FIELDS; MAGNETOACOUSTIC WAVES; MAGNETOHYDRODYNAMICS; MAXWELL EQUATIONS; OSCILLATIONS; PLASMA; PLASMA HEATING; RECOMBINATION; SHOCK WAVES; SUN; WAVE PROPAGATION

Citation Formats

Maneva, Yana G., Laguna, Alejandro Alvarez, Poedts, Stefaan, and Lani, Andrea, E-mail: yana.maneva@ws.kuleuven.be, E-mail: stefaan.poedts@wis.kuleuven.be, E-mail: alejandro.alvarez.laguna@vki.ac.be, E-mail: lani@vki.ac.be. Multi-fluid Modeling of Magnetosonic Wave Propagation in the Solar Chromosphere: Effects of Impact Ionization and Radiative Recombination. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA5B83.
Maneva, Yana G., Laguna, Alejandro Alvarez, Poedts, Stefaan, & Lani, Andrea, E-mail: yana.maneva@ws.kuleuven.be, E-mail: stefaan.poedts@wis.kuleuven.be, E-mail: alejandro.alvarez.laguna@vki.ac.be, E-mail: lani@vki.ac.be. Multi-fluid Modeling of Magnetosonic Wave Propagation in the Solar Chromosphere: Effects of Impact Ionization and Radiative Recombination. United States. doi:10.3847/1538-4357/AA5B83.
Maneva, Yana G., Laguna, Alejandro Alvarez, Poedts, Stefaan, and Lani, Andrea, E-mail: yana.maneva@ws.kuleuven.be, E-mail: stefaan.poedts@wis.kuleuven.be, E-mail: alejandro.alvarez.laguna@vki.ac.be, E-mail: lani@vki.ac.be. Mon . "Multi-fluid Modeling of Magnetosonic Wave Propagation in the Solar Chromosphere: Effects of Impact Ionization and Radiative Recombination". United States. doi:10.3847/1538-4357/AA5B83.
@article{osti_22663774,
title = {Multi-fluid Modeling of Magnetosonic Wave Propagation in the Solar Chromosphere: Effects of Impact Ionization and Radiative Recombination},
author = {Maneva, Yana G. and Laguna, Alejandro Alvarez and Poedts, Stefaan and Lani, Andrea, E-mail: yana.maneva@ws.kuleuven.be, E-mail: stefaan.poedts@wis.kuleuven.be, E-mail: alejandro.alvarez.laguna@vki.ac.be, E-mail: lani@vki.ac.be},
abstractNote = {In order to study chromospheric magnetosonic wave propagation including, for the first time, the effects of ion–neutral interactions in the partially ionized solar chromosphere, we have developed a new multi-fluid computational model accounting for ionization and recombination reactions in gravitationally stratified magnetized collisional media. The two-fluid model used in our 2D numerical simulations treats neutrals as a separate fluid and considers charged species (electrons and ions) within the resistive MHD approach with Coulomb collisions and anisotropic heat flux determined by Braginskiis transport coefficients. The electromagnetic fields are evolved according to the full Maxwell equations and the solenoidality of the magnetic field is enforced with a hyperbolic divergence-cleaning scheme. The initial density and temperature profiles are similar to VAL III chromospheric model in which dynamical, thermal, and chemical equilibrium are considered to ensure comparison to existing MHD models and avoid artificial numerical heating. In this initial setup we include simple homogeneous flux tube magnetic field configuration and an external photospheric velocity driver to simulate the propagation of MHD waves in the partially ionized reactive chromosphere. In particular, we investigate the loss of chemical equilibrium and the plasma heating related to the steepening of fast magnetosonic wave fronts in the gravitationally stratified medium.},
doi = {10.3847/1538-4357/AA5B83},
journal = {Astrophysical Journal},
number = 2,
volume = 836,
place = {United States},
year = {Mon Feb 20 00:00:00 EST 2017},
month = {Mon Feb 20 00:00:00 EST 2017}
}
  • We investigate the effects of interactions between ions and neutrals on the chromosphere and overlying corona using 2.5D radiative MHD simulations with the Bifrost code. We have extended the code capabilities implementing ion–neutral interaction effects using the generalized Ohm’s law, i.e., we include the Hall term and the ambipolar diffusion (Pedersen dissipation) in the induction equation. Our models span from the upper convection zone to the corona, with the photosphere, chromosphere, and transition region partially ionized. Our simulations reveal that the interactions between ionized particles and neutral particles have important consequences for the magnetothermodynamics of these modeled layers: (1) ambipolarmore » diffusion increases the temperature in the chromosphere; (2) sporadically the horizontal magnetic field in the photosphere is diffused into the chromosphere, due to the large ambipolar diffusion; (3) ambipolar diffusion concentrates electrical currents, leading to more violent jets and reconnection processes, resulting in (3a) the formation of longer and faster spicules, (3b) heating of plasma during the spicule evolution, and (3c) decoupling of the plasma and magnetic field in spicules. Our results indicate that ambipolar diffusion is a critical ingredient for understanding the magnetothermodynamic properties in the chromosphere and transition region. The numerical simulations have been made publicly available, similar to previous Bifrost simulations. This will allow the community to study realistic numerical simulations with a wider range of magnetic field configurations and physics modules than previously possible.« less
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