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Title: Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere

Abstract

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) ambipolar 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, similarmore » 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

Authors:
 [1]; ;  [2]; ;  [3];  [4]
  1. Bay Area Environmental Research Institute, Petaluma, CA 94952 (United States)
  2. Lockheed Martin Solar and Astrophysics Laboratory, Palo Alto, CA 94304 (United States)
  3. Institute of Theoretical Astrophysics, University of Oslo, P.O. Box 1029 Blindern, NO-0315 Oslo (Norway)
  4. Instituto de Astrofísica de Canarias, E-38200 La Laguna (Tenerife) (Spain)
Publication Date:
OSTI Identifier:
22679824
Resource Type:
Journal Article
Resource Relation:
Journal Name: Astrophysical Journal; Journal Volume: 847; Journal Issue: 1; Other Information: Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
79 ASTROPHYSICS, COSMOLOGY AND ASTRONOMY; AMBIPOLAR DIFFUSION; CHROMOSPHERE; COMPUTERIZED SIMULATION; INTERACTIONS; IONIZATION; IONS; LAYERS; MAGNETIC FIELD CONFIGURATIONS; MAGNETIC FIELDS; MAGNETOHYDRODYNAMICS; PHOTOSPHERE; PLASMA; RADIANT HEAT TRANSFER; SOLAR PROMINENCES; STAR EVOLUTION; SUN; TWO-DIMENSIONAL CALCULATIONS

Citation Formats

Martínez-Sykora, Juan, Pontieu, Bart De, Hansteen, Viggo H., Carlsson, Mats, Gudiksen, Boris V., and Nóbrega-Siverio, Daniel, E-mail: juanms@lmsal.com. Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere. United States: N. p., 2017. Web. doi:10.3847/1538-4357/AA8866.
Martínez-Sykora, Juan, Pontieu, Bart De, Hansteen, Viggo H., Carlsson, Mats, Gudiksen, Boris V., & Nóbrega-Siverio, Daniel, E-mail: juanms@lmsal.com. Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere. United States. doi:10.3847/1538-4357/AA8866.
Martínez-Sykora, Juan, Pontieu, Bart De, Hansteen, Viggo H., Carlsson, Mats, Gudiksen, Boris V., and Nóbrega-Siverio, Daniel, E-mail: juanms@lmsal.com. Wed . "Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere". United States. doi:10.3847/1538-4357/AA8866.
@article{osti_22679824,
title = {Two-dimensional Radiative Magnetohydrodynamic Simulations of Partial Ionization in the Chromosphere. II. Dynamics and Energetics of the Low Solar Atmosphere},
author = {Martínez-Sykora, Juan and Pontieu, Bart De and Hansteen, Viggo H. and Carlsson, Mats and Gudiksen, Boris V. and Nóbrega-Siverio, Daniel, E-mail: juanms@lmsal.com},
abstractNote = {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) ambipolar 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.},
doi = {10.3847/1538-4357/AA8866},
journal = {Astrophysical Journal},
number = 1,
volume = 847,
place = {United States},
year = {Wed Sep 20 00:00:00 EDT 2017},
month = {Wed Sep 20 00:00:00 EDT 2017}
}