Effect of Radiation on Chromospheric Magnetic Reconnection: Reactive and Collisional Multifluid Simulations
Abstract
We study magnetic reconnection under chromospheric conditions in five different ionization levels from 0.5% to 50% using a selfconsistent twofluid (ions + neutrals) model that accounts for compressibility, collisional effects, chemical inequilibrium, and anisotropic heat conduction. Results with and without radiation are compared, using two models for the radiative losses: an optically thin radiation loss function, and an approximation of the radiative losses of a plasma with photospheric abundances. The results without radiation show that reconnection occurs faster for the weakly ionized cases as a result of the effect of ambipolar diffusion and fast recombination. The tearing mode instability appears earlier in the low ionized cases and grows rapidly. We find that radiative losses have a stronger effect than was found in previous results as the cooling changes the plasma pressure and the concentration of ions inside the current sheet. This affects the ambipolar diffusion and the chemical equilibrium, resulting in thin current sheets and enhanced reconnection. The results quantify this complex nonlinear interaction by showing that a strong cooling produces faster reconnections than have been found in models without radiation. The results accounting for radiation show timescales and outflows comparable to spicules and chromospheric jets.
 Authors:
 Centre for Mathematical PlasmaAstrophysics, KU Leuven, Leuven (Belgium)
 Aeronautics and Aerospace Department, von Karman Institute for Fluid Dynamics, SintGenesiusRode (Belgium)
 NASA Ames Research Center, MS 2303, Moffett Field, CA 94035 (United States)
 Publication Date:
 OSTI Identifier:
 22663473
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Astrophysical Journal; Journal Volume: 842; 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; AMBIPOLAR DIFFUSION; ANISOTROPY; APPROXIMATIONS; CHROMOSPHERE; COMPRESSIBILITY; CONCENTRATION RATIO; EQUILIBRIUM; FLUIDS; INTERACTIONS; IONIZATION; MAGNETIC FIELDS; MAGNETIC RECONNECTION; PLASMA PRESSURE; RADIANT HEAT TRANSFER; RECOMBINATION; SIMULATION; SOLAR PROMINENCES; SUN; TEARING INSTABILITY; THERMAL CONDUCTION
Citation Formats
Alvarez Laguna, A., Poedts, S., Lani, A., Deconinck, H., and Mansour, N. N. Effect of Radiation on Chromospheric Magnetic Reconnection: Reactive and Collisional Multifluid Simulations. United States: N. p., 2017.
Web. doi:10.3847/15384357/AA7554.
Alvarez Laguna, A., Poedts, S., Lani, A., Deconinck, H., & Mansour, N. N. Effect of Radiation on Chromospheric Magnetic Reconnection: Reactive and Collisional Multifluid Simulations. United States. doi:10.3847/15384357/AA7554.
Alvarez Laguna, A., Poedts, S., Lani, A., Deconinck, H., and Mansour, N. N. 2017.
"Effect of Radiation on Chromospheric Magnetic Reconnection: Reactive and Collisional Multifluid Simulations". United States.
doi:10.3847/15384357/AA7554.
@article{osti_22663473,
title = {Effect of Radiation on Chromospheric Magnetic Reconnection: Reactive and Collisional Multifluid Simulations},
author = {Alvarez Laguna, A. and Poedts, S. and Lani, A. and Deconinck, H. and Mansour, N. N.},
abstractNote = {We study magnetic reconnection under chromospheric conditions in five different ionization levels from 0.5% to 50% using a selfconsistent twofluid (ions + neutrals) model that accounts for compressibility, collisional effects, chemical inequilibrium, and anisotropic heat conduction. Results with and without radiation are compared, using two models for the radiative losses: an optically thin radiation loss function, and an approximation of the radiative losses of a plasma with photospheric abundances. The results without radiation show that reconnection occurs faster for the weakly ionized cases as a result of the effect of ambipolar diffusion and fast recombination. The tearing mode instability appears earlier in the low ionized cases and grows rapidly. We find that radiative losses have a stronger effect than was found in previous results as the cooling changes the plasma pressure and the concentration of ions inside the current sheet. This affects the ambipolar diffusion and the chemical equilibrium, resulting in thin current sheets and enhanced reconnection. The results quantify this complex nonlinear interaction by showing that a strong cooling produces faster reconnections than have been found in models without radiation. The results accounting for radiation show timescales and outflows comparable to spicules and chromospheric jets.},
doi = {10.3847/15384357/AA7554},
journal = {Astrophysical Journal},
number = 2,
volume = 842,
place = {United States},
year = 2017,
month = 6
}

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