MAGNETIC TRANSPORT ON THE SOLAR ATMOSPHERE BY LAMINAR AND TURBULENT AMBIPOLAR DIFFUSION

Journal Article · Fri Sep 10 04:00:00 EDT 2010 · Astrophysical Journal

DOI:https://doi.org/10.1088/0004-637X/720/2/1311· OSTI ID:21460050

Hiraki, Y ^[1]; Krishan, V ^[2]; Masuda, S ^[3]

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1. National Institute for Fusion Science (NIFS), Toki, Gifu (Japan)
2. Raman Research Institute, Bangalore 560 080 (India)
3. Solar-Terrestrial Environment Laboratory, Nagoya University, Nagoya, Aichi (Japan)

The lower solar atmosphere consists of partially ionized turbulent plasmas harboring velocity field, magnetic field, and current density fluctuations. The correlations among these small-scale fluctuations give rise to large-scale flows and magnetic fields which decisively affect all transport processes. The three-fluid system consisting of electrons, ions, and neutral particles supports nonideal effects such as the Hall effect and ambipolar diffusion. Here, we study magnetic transport by the laminar- and turbulent-scale ambipolar diffusion processes using a simple model of the magnetic induction equation. Based on a linear analysis of the induction equation, we perform a one-dimensional numerical simulation to study the laminar ambipolar effect on medium-scale magnetic field structures. The nonlinearity of the laminar ambipolar diffusion creates magnetic structures with sharp gradients in the scale of hundreds of kilometers. We expect that these can be amenable to processes such as magnetic reconnection and energy release therefrom for heating and flaring of the solar plasma. Analyzing the characteristic timescales of these processes, we find that the turbulent diffusion timescale is smaller by several orders of magnitude than the laminar diffusion timescale. The effect of the modeled turbulent ambipolar diffusion on the obtained field structures is briefly discussed.

• OSTI ID: 21460050
• Journal Information: Astrophysical Journal, Journal Name: Astrophysical Journal Journal Issue: 2 Vol. 720; ISSN ASJOAB; ISSN 0004-637X
• Country of Publication: United States
• Language: English

Related Subjects

79 ASTRONOMY AND ASTROPHYSICS
AMBIPOLAR DIFFUSION
ATMOSPHERES
CHROMOSPHERE
COMPUTERIZED SIMULATION
CURRENT DENSITY
DIFFUSION
FLUID MECHANICS
HALL EFFECT
HYDRODYNAMICS
MAGNETIC FIELDS
MAGNETIC RECONNECTION
MAGNETOHYDRODYNAMICS
MAIN SEQUENCE STARS
MECHANICS
NEUTRAL PARTICLES
NONLINEAR PROBLEMS
ONE-DIMENSIONAL CALCULATIONS
SIMULATION
SOLAR ACTIVITY
SOLAR ATMOSPHERE
SOLAR CORONA
SOLAR FLARES
STARS
STELLAR ACTIVITY
STELLAR ATMOSPHERES
STELLAR CORONAE
STELLAR FLARES
SUN